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Sample records for orestias agassii cuvier

  1. The complete mitochondrial genome of the killifish Orestias sp. (Cyprinodontiformes, Cyprinodontidae) from the high Andean range.

    PubMed

    Quezada-Romegialli, Claudio; Guerrero, Claudia Jimena; Véliz, David; Vila, Irma

    2016-07-01

    The killifish genus Orestias is endemic to freshwater ecosystems in the High Andes of Peru, Bolivia and Chile. Phylogenetic and phylogeographic studies with partial mitochondrial genes have failed to resolve relationship among species, needing more comprehensive approaches. In this study, we described the complete mitochondrial genome of Orestias sp. from Lirima, northern Chile, with the aim to provide useful data for phylogenetic purposes and species delimitation. The mitochondrial genome was assembled with 2.6 million of reads obtained through an Ion Torrent (chip 318) sequencer. The circular sequence of 16,617 bp showed the following nucleotide composition: A, 26.7%, C, 27.1%, G, 17.0%, and T, 29.2%. Gene composition and structure were similar to other fish sequences available, and comprised 13 protein-coding genes, 12S and 16S rRNA, 22 tRNA genes, and a control region.

  2. The complete mitochondrial genome of the killifish Orestias sp. (Cyprinodontiformes, Cyprinodontidae) from the high Andean range.

    PubMed

    Quezada-Romegialli, Claudio; Guerrero, Claudia Jimena; Véliz, David; Vila, Irma

    2016-07-01

    The killifish genus Orestias is endemic to freshwater ecosystems in the High Andes of Peru, Bolivia and Chile. Phylogenetic and phylogeographic studies with partial mitochondrial genes have failed to resolve relationship among species, needing more comprehensive approaches. In this study, we described the complete mitochondrial genome of Orestias sp. from Lirima, northern Chile, with the aim to provide useful data for phylogenetic purposes and species delimitation. The mitochondrial genome was assembled with 2.6 million of reads obtained through an Ion Torrent (chip 318) sequencer. The circular sequence of 16,617 bp showed the following nucleotide composition: A, 26.7%, C, 27.1%, G, 17.0%, and T, 29.2%. Gene composition and structure were similar to other fish sequences available, and comprised 13 protein-coding genes, 12S and 16S rRNA, 22 tRNA genes, and a control region. PMID:26119115

  3. Phylogenetic and phylogeographic analysis of the genus Orestias (Teleostei: Cyprinodontidae) in the southern Chilean Altiplano: the relevance of ancient and recent divergence processes in speciation.

    PubMed

    Vila, I; Morales, P; Scott, S; Poulin, E; Véliz, D; Harrod, C; Méndez, M A

    2013-03-01

    This study presents phylogenetic molecular data of the Chilean species of Orestias to propose an allopatric divergence hypothesis and phylogeographic evidence that suggests the relevance of abiotic factors in promoting population divergence in this complex. The results reveal that diversification is still ongoing, e.g. in the Ascotán salt pan, where populations of Orestias ascotanensis restricted to individual freshwater springs exhibit strong genetic differentiation, reflecting putative independent evolutionary units. Diversification of Orestias in the southern Altiplano may be linked to historical vicariant events and contemporary variation in water level; these processes may have affected the populations from the Plio-Pleistocene until the present.

  4. A RAD-based phylogenetics for Orestias fishes from Lake Titicaca.

    PubMed

    Takahashi, Tetsumi; Moreno, Edmundo

    2015-12-01

    The fish genus Orestias is endemic to the Andes highlands, and Lake Titicaca is the centre of the species diversity of the genus. Previous phylogenetic studies based on a single locus of mitochondrial and nuclear DNA strongly support the monophyly of a group composed of many of species endemic to the Lake Titicaca basin (the Lake Titicaca radiation), but the relationships among the species in the radiation remain unclear. Recently, restriction site-associated DNA (RAD) sequencing, which can produce a vast number of short sequences from various loci of nuclear DNA, has emerged as a useful way to resolve complex phylogenetic problems. To propose a new phylogenetic hypothesis of Orestias fishes of the Lake Titicaca radiation, we conducted a cluster analysis based on morphological similarities among fish samples and a molecular phylogenetic analysis based on RAD sequencing. From a morphological cluster analysis, we recognised four species groups in the radiation, and three of the four groups were resolved as monophyletic groups in maximum-likelihood trees based on RAD sequencing data. The other morphology-based group was not resolved as a monophyletic group in molecular phylogenies, and some members of the group were diverged from its sister group close to the root of the Lake Titicaca radiation. The evolution of these fishes is discussed from the phylogenetic relationships.

  5. Darwin, Cuvier and Geoffroy: comments and questions.

    PubMed

    Grene, M

    2001-01-01

    In writing, in the Origin of Species, of 'two great laws' on which organic beings are formed, 'Unity of Type' and 'Conditions of Existence', Darwin was referring to the famous opposition between Cuvier and Geoffroy Saint-Hilaire, first stated publicly in the spring of 1830. After a brief statement of the chief points at issue in the debate, I raise the question of Darwin's attitude to the disagreement and the views of the two protagonists. There are numerous earlier, and some later, references to Cuvier and Geoffroy in the Darwin archives, notebooks, marginalia and correspondence. An examination of these materials suggests a shift in Darwin's sympathies, from Geoffroy to Cuvier. However, some of Geoffroy's principles are retained, and, in adopting Cuvier's phrase 'conditions of existence', Darwin partly alters its meaning. Finally, since originally, and in its adoption by such writers as Whewell and Owen, the expression 'conditions of existence' was interpreted as entailing design or final cause, I consider the vexed question of Darwin's attitude to teleology. PMID:12557693

  6. Non-invasive ancient DNA protocol for fluid-preserved specimens and phylogenetic systematics of the genus Orestias (Teleostei: Cyprinodontidae).

    PubMed

    Garrigos, Yareli Esquer; Hugueny, Bernard; Koerner, Kellie; Ibañez, Carla; Bonillo, Celine; Pruvost, Patrice; Causse, Romain; Cruaud, Corinne; Gaubert, Philippe

    2013-01-01

    Specimens stored in museum collections represent a crucial source of morphological and genetic information, notably for taxonomically problematic groups and extinct taxa. Although fluid-preserved specimens of groups such as teleosts may constitute an almost infinite source of DNA, few ancient DNA protocols have been applied to such material. In this study, we describe a non-invasive Guanidine-based (GuSCN) ancient DNA extraction protocol adapted to fluid-preserved specimens that we use to re-assess the systematics of the genus Orestias (Cyprinodontidae: Teleostei). The latter regroups pupfishes endemic to the inter-Andean basin that have been considered as a 'species flock', and for which the morphology-based taxonomic delimitations have been hotly debated. We extracted DNA from the type specimens of Orestias kept at the Muséum National d'Histoire Naturelle of Paris, France, including the extinct species O. cuvieri. We then built the first molecular (control region [CR] and rhodopsin [RH]) phylogeny including historical and recently collected representatives of all the Orestias complexes as recognized by Parenti (1984a): agassizii, cuvieri, gilsoni and mulleri. Our ancient DNA extraction protocol was validated after PCR amplification through an approach based on fragment-by-fragment chimera detection. After optimization, we were able to amplify < 200 bp fragments from both mitochondrial and nuclear DNA (CR and RH, respectively) from probably formalin-fixed type specimens bathed entirely in the extraction fluid. Most of the individuals exhibited few modifications of their external structures after GuSCN bath. Our approach combining type material and 'fresh' specimens allowed us to taxonomically delineate four clades recovered from the well-resolved CR tree into four redefined complexes: agassizii (sensu stricto, i.e. excluding luteus-like species), luteus, cuvieri and gilsoni. The mulleri complex is polyphyletic. Our phylogenetic analyses based on both

  7. The complete mitochondrial genome of the endemic and threatened killifish Orestias ascotanensis Parenti, 1984 (Cyprinodontiformes, Cyprinodontidae) from the High Andes.

    PubMed

    Quezada-Romegialli, Claudio; Guerrero, Claudia Jimena; Véliz, David; Vila, Irma

    2016-07-01

    The killifish Orestias ascotanensis is endemic to the small isolated springs of Ascotán salt pan in the Central High Andes, Chile. Due to small populations, mining activity, and increasing aridity, this species is catalogued in danger of extinction. The complete mitochondrial genome of O. ascotanesis was assembled with an Ion Torrent sequencer (chip 318) that produced 2.61 million of reads. The 16 617 bp of the entire genome consisted of 22 transfer RNAs, 2 ribosomal RNAs, 13 protein-coding genes, and a control region, showing that the gene composition and arrangement match to that reported for most fishes.

  8. The complete mitochondrial genome of the endemic and threatened killifish Orestias ascotanensis Parenti, 1984 (Cyprinodontiformes, Cyprinodontidae) from the High Andes.

    PubMed

    Quezada-Romegialli, Claudio; Guerrero, Claudia Jimena; Véliz, David; Vila, Irma

    2016-07-01

    The killifish Orestias ascotanensis is endemic to the small isolated springs of Ascotán salt pan in the Central High Andes, Chile. Due to small populations, mining activity, and increasing aridity, this species is catalogued in danger of extinction. The complete mitochondrial genome of O. ascotanesis was assembled with an Ion Torrent sequencer (chip 318) that produced 2.61 million of reads. The 16 617 bp of the entire genome consisted of 22 transfer RNAs, 2 ribosomal RNAs, 13 protein-coding genes, and a control region, showing that the gene composition and arrangement match to that reported for most fishes. PMID:26152352

  9. Liposarcoma in clownfish, Amphiprion ocellaris Cuvier, produced in indoor aquaculture.

    PubMed

    Sharon, G; Benharroch, D; Kachko, L; Reis-Hevlin, N; Zilberg, D

    2015-06-01

    Clownfish, Amphiprion ocellaris Cuvier, produced and grown in an experimental indoor aquaculture facility, presented with lipomatous tumours. A total of 14 affected fish were examined. Based on the total number of fish at the aquaculture facility at the time of outbreak of this pathology, the scope of the incident is estimated to be 1 of 300 fish. The tumours were characterized by the presence of mature adipocytes of variable sizes, lipoblasts and by an invasive behaviour, which affected internal organs, muscle, central nervous system and, in one case, an eye. Detailed macroscopic and histopathological features are presented. The suggested diagnosis is that of a well-differentiated liposarcoma, a diagnosis so far never applied to fish. The limited outbreak of the neoplasm lasted a few months in 2011 and did not recur. Possible factors leading to this phenomenon, notably the metastasis, are discussed. PMID:24917512

  10. Liposarcoma in clownfish, Amphiprion ocellaris Cuvier, produced in indoor aquaculture.

    PubMed

    Sharon, G; Benharroch, D; Kachko, L; Reis-Hevlin, N; Zilberg, D

    2015-06-01

    Clownfish, Amphiprion ocellaris Cuvier, produced and grown in an experimental indoor aquaculture facility, presented with lipomatous tumours. A total of 14 affected fish were examined. Based on the total number of fish at the aquaculture facility at the time of outbreak of this pathology, the scope of the incident is estimated to be 1 of 300 fish. The tumours were characterized by the presence of mature adipocytes of variable sizes, lipoblasts and by an invasive behaviour, which affected internal organs, muscle, central nervous system and, in one case, an eye. Detailed macroscopic and histopathological features are presented. The suggested diagnosis is that of a well-differentiated liposarcoma, a diagnosis so far never applied to fish. The limited outbreak of the neoplasm lasted a few months in 2011 and did not recur. Possible factors leading to this phenomenon, notably the metastasis, are discussed.

  11. Citrobacter freundii septicemia in a stranded newborn Cuvier's beaked whale (Ziphius cavirostris).

    PubMed

    Fernández, Antonio; Vela, Ana Isabel; Andrada, Marisa; Herraez, Pedro; Díaz-Delgado, Josue; Domínguez, Lucas; Arbelo, Manuel

    2011-10-01

    Citrobacter freundii, a gram-negative enterobacterium, may cause fatal septicemia in humans and animals. Its potential pathogenic role in cetaceans (bottlenose dolphins and beluga whales) has been hypothesized. Here we describe fatal C. freundii septicemia in a stranded newborn Cuvier's beaked whale (Ziphius cavirostris). PMID:22102682

  12. Citrobacter freundii septicemia in a stranded newborn Cuvier's beaked whale (Ziphius cavirostris).

    PubMed

    Fernández, Antonio; Vela, Ana Isabel; Andrada, Marisa; Herraez, Pedro; Díaz-Delgado, Josue; Domínguez, Lucas; Arbelo, Manuel

    2011-10-01

    Citrobacter freundii, a gram-negative enterobacterium, may cause fatal septicemia in humans and animals. Its potential pathogenic role in cetaceans (bottlenose dolphins and beluga whales) has been hypothesized. Here we describe fatal C. freundii septicemia in a stranded newborn Cuvier's beaked whale (Ziphius cavirostris).

  13. Three-dimensional tracking of Cuvier's beaked whales' echolocation sounds using nested hydrophone arrays.

    PubMed

    Gassmann, Martin; Wiggins, Sean M; Hildebrand, John A

    2015-10-01

    Cuvier's beaked whales (Ziphius cavirostris) were tracked using two volumetric small-aperture (∼1 m element spacing) hydrophone arrays, embedded into a large-aperture (∼1 km element spacing) seafloor hydrophone array of five nodes. This array design can reduce the minimum number of nodes that are needed to record the arrival of a strongly directional echolocation sound from 5 to 2, while providing enough time-differences of arrivals for a three-dimensional localization without depending on any additional information such as multipath arrivals. To illustrate the capabilities of this technique, six encounters of up to three Cuvier's beaked whales were tracked over a two-month recording period within an area of 20 km(2) in the Southern California Bight. Encounter periods ranged from 11 min to 33 min. Cuvier's beaked whales were found to reduce the time interval between echolocation clicks while alternating between two inter-click-interval regimes during their descent towards the seafloor. Maximum peak-to-peak source levels of 179 and 224 dB re 1 μPa @ 1 m were estimated for buzz sounds and on-axis echolocation clicks (directivity index = 30 dB), respectively. Source energy spectra of the on-axis clicks show significant frequency components between 70 and 90 kHz, in addition to their typically noted FM upsweep at 40-60 kHz.

  14. Is the tiger shark Galeocerdo cuvier a coastal species? Expanding its distribution range in the Atlantic Ocean using at-sea observer data.

    PubMed

    Domingo, A; Coelho, R; Cortes, E; Garcia-Cortes, B; Mas, F; Mejuto, J; Miller, P; Ramos-Cartelle, A; Santos, M N; Yokawa, K

    2016-03-01

    The occurrence of tiger shark Galeocerdo cuvier in the Atlantic Ocean was assessed using at-sea observer data from multiple pelagic longline fisheries. Geographic positions of 2764 G. cuvier recorded between 1992 and 2013 and covering a wide area of the Atlantic Ocean were compared with the currently accepted distribution ranges of the species. Most records fell outside those ranges in both the Southern and Northern Hemispheres, which strongly suggests that the distribution range of G. cuvier in the open ocean is considerably larger than previously described.

  15. Is the tiger shark Galeocerdo cuvier a coastal species? Expanding its distribution range in the Atlantic Ocean using at-sea observer data.

    PubMed

    Domingo, A; Coelho, R; Cortes, E; Garcia-Cortes, B; Mas, F; Mejuto, J; Miller, P; Ramos-Cartelle, A; Santos, M N; Yokawa, K

    2016-03-01

    The occurrence of tiger shark Galeocerdo cuvier in the Atlantic Ocean was assessed using at-sea observer data from multiple pelagic longline fisheries. Geographic positions of 2764 G. cuvier recorded between 1992 and 2013 and covering a wide area of the Atlantic Ocean were compared with the currently accepted distribution ranges of the species. Most records fell outside those ranges in both the Southern and Northern Hemispheres, which strongly suggests that the distribution range of G. cuvier in the open ocean is considerably larger than previously described. PMID:26817438

  16. Trackline and point detection probabilities for acoustic surveys of Cuvier's and Blainville's beaked whales.

    PubMed

    Barlow, Jay; Tyack, Peter L; Johnson, Mark P; Baird, Robin W; Schorr, Gregory S; Andrews, Russel D; Aguilar de Soto, Natacha

    2013-09-01

    Acoustic survey methods can be used to estimate density and abundance using sounds produced by cetaceans and detected using hydrophones if the probability of detection can be estimated. For passive acoustic surveys, probability of detection at zero horizontal distance from a sensor, commonly called g(0), depends on the temporal patterns of vocalizations. Methods to estimate g(0) are developed based on the assumption that a beaked whale will be detected if it is producing regular echolocation clicks directly under or above a hydrophone. Data from acoustic recording tags placed on two species of beaked whales (Cuvier's beaked whale-Ziphius cavirostris and Blainville's beaked whale-Mesoplodon densirostris) are used to directly estimate the percentage of time they produce echolocation clicks. A model of vocal behavior for these species as a function of their diving behavior is applied to other types of dive data (from time-depth recorders and time-depth-transmitting satellite tags) to indirectly determine g(0) in other locations for low ambient noise conditions. Estimates of g(0) for a single instant in time are 0.28 [standard deviation (s.d.) = 0.05] for Cuvier's beaked whale and 0.19 (s.d. = 0.01) for Blainville's beaked whale.

  17. Gastrointestinal helminths of Cuvier's beaked whales, Ziphius cavirostris, from the western Mediterranean.

    PubMed

    Fernández, Mercedes; Aznar, F Javier; Montero, Francisco E; Georgiev, Boyko B; Raga, Juan A

    2004-04-01

    We examined the gastrointestinal helminth fauna of 2 Cuvier's beaked whales, Ziphius cavirostris, stranded on the Spanish Mediterranean coast. Information regarding intestinal parasites of this species is provided for the first time. Six helminth taxa were identified. Thirty type II larvae of the nematode Anisakis sp. were found in the stomach and the intestine of both hosts; 2 type I larvae of Anisakis sp. were found in the intestine of 1 host. One juvenile of the acanthocephalan Bolbosoma vasculosum was found in the intestine; the metacestode Scolex pleuronectis was found mainly in the terminal colon and the anal crypts of both hosts; adult cestodes of Tetrabothrius sp., which may represent a new species, were collected from the duodenum of 1 host. Composition of the intestinal parasitic community is similar to that of other oceanic cetaceans, which mostly include species of Bolbosoma and tetrabothriids (Cestoda).

  18. Octopus vulgaris (Cuvier, 1797) in the Mediterranean Sea: Genetic Diversity and Population Structure

    PubMed Central

    De Luca, Daniele; Catanese, Gaetano; Procaccini, Gabriele; Fiorito, Graziano

    2016-01-01

    The common octopus, Octopus vulgaris Cuvier 1797, is a largely exploited cephalopod species in the Mediterranean Sea and the Atlantic Ocean, as well as along the coasts of Africa, Brazil and Japan, where its taxonomic identity is still debated. The assessment of its genetic structure is a pressing need to correctly manage the resource and to avoid overfishing and collapsing of local stocks. Here we analysed genetic variation and population structure of O. vulgaris using thirteen microsatellite loci in seven sampling localities from the Mediterranean Sea and one from the Atlantic Ocean. We also used a DNA barcoding approach by COI gene fragment to understand the phylogenetic relationships among the specimens here investigated and the ones whose sequences are available in literature. Our results reveal high levels of allelic richness and moderate heterozygosity in all samples investigated, and a pronounced differentiation of the Atlantic and Sicilian specimens. This latter aspect seems to support the isolation of the biota within the Strait of Messina. A certain degree of differentiation was detected among the other geographic samples within the Mediterranean Sea, which is more compatible with an island model than isolation by distance. The occurrence of null alleles affected more genetic diversity indices than population structure estimations. This study provides new insights about the genetic diversity and structure of O. vulgaris in the area of interest, which can be used as guidelines for a fisheries management perspective. PMID:26881847

  19. Octopus vulgaris (Cuvier, 1797) in the Mediterranean Sea: Genetic Diversity and Population Structure.

    PubMed

    De Luca, Daniele; Catanese, Gaetano; Procaccini, Gabriele; Fiorito, Graziano

    2016-01-01

    The common octopus, Octopus vulgaris Cuvier 1797, is a largely exploited cephalopod species in the Mediterranean Sea and the Atlantic Ocean, as well as along the coasts of Africa, Brazil and Japan, where its taxonomic identity is still debated. The assessment of its genetic structure is a pressing need to correctly manage the resource and to avoid overfishing and collapsing of local stocks. Here we analysed genetic variation and population structure of O. vulgaris using thirteen microsatellite loci in seven sampling localities from the Mediterranean Sea and one from the Atlantic Ocean. We also used a DNA barcoding approach by COI gene fragment to understand the phylogenetic relationships among the specimens here investigated and the ones whose sequences are available in literature. Our results reveal high levels of allelic richness and moderate heterozygosity in all samples investigated, and a pronounced differentiation of the Atlantic and Sicilian specimens. This latter aspect seems to support the isolation of the biota within the Strait of Messina. A certain degree of differentiation was detected among the other geographic samples within the Mediterranean Sea, which is more compatible with an island model than isolation by distance. The occurrence of null alleles affected more genetic diversity indices than population structure estimations. This study provides new insights about the genetic diversity and structure of O. vulgaris in the area of interest, which can be used as guidelines for a fisheries management perspective. PMID:26881847

  20. First direct measurements of behavioural responses by Cuvier's beaked whales to mid-frequency active sonar.

    PubMed

    DeRuiter, Stacy L; Southall, Brandon L; Calambokidis, John; Zimmer, Walter M X; Sadykova, Dinara; Falcone, Erin A; Friedlaender, Ari S; Joseph, John E; Moretti, David; Schorr, Gregory S; Thomas, Len; Tyack, Peter L

    2013-08-23

    Most marine mammal- strandings coincident with naval sonar exercises have involved Cuvier's beaked whales (Ziphius cavirostris). We recorded animal movement and acoustic data on two tagged Ziphius and obtained the first direct measurements of behavioural responses of this species to mid-frequency active (MFA) sonar signals. Each recording included a 30-min playback (one 1.6-s simulated MFA sonar signal repeated every 25 s); one whale was also incidentally exposed to MFA sonar from distant naval exercises. Whales responded strongly to playbacks at low received levels (RLs; 89-127 dB re 1 µPa): after ceasing normal fluking and echolocation, they swam rapidly, silently away, extending both dive duration and subsequent non-foraging interval. Distant sonar exercises (78-106 dB re 1 µPa) did not elicit such responses, suggesting that context may moderate reactions. The observed responses to playback occurred at RLs well below current regulatory thresholds; equivalent responses to operational sonars could elevate stranding risk and reduce foraging efficiency.

  1. Octopus vulgaris (Cuvier, 1797) in the Mediterranean Sea: Genetic Diversity and Population Structure.

    PubMed

    De Luca, Daniele; Catanese, Gaetano; Procaccini, Gabriele; Fiorito, Graziano

    2016-01-01

    The common octopus, Octopus vulgaris Cuvier 1797, is a largely exploited cephalopod species in the Mediterranean Sea and the Atlantic Ocean, as well as along the coasts of Africa, Brazil and Japan, where its taxonomic identity is still debated. The assessment of its genetic structure is a pressing need to correctly manage the resource and to avoid overfishing and collapsing of local stocks. Here we analysed genetic variation and population structure of O. vulgaris using thirteen microsatellite loci in seven sampling localities from the Mediterranean Sea and one from the Atlantic Ocean. We also used a DNA barcoding approach by COI gene fragment to understand the phylogenetic relationships among the specimens here investigated and the ones whose sequences are available in literature. Our results reveal high levels of allelic richness and moderate heterozygosity in all samples investigated, and a pronounced differentiation of the Atlantic and Sicilian specimens. This latter aspect seems to support the isolation of the biota within the Strait of Messina. A certain degree of differentiation was detected among the other geographic samples within the Mediterranean Sea, which is more compatible with an island model than isolation by distance. The occurrence of null alleles affected more genetic diversity indices than population structure estimations. This study provides new insights about the genetic diversity and structure of O. vulgaris in the area of interest, which can be used as guidelines for a fisheries management perspective.

  2. Anatomic geometry of sound transmission and reception in Cuvier's beaked whale (Ziphius cavirostris).

    PubMed

    Cranford, Ted W; McKenna, Megan F; Soldevilla, Melissa S; Wiggins, Sean M; Goldbogen, Jeremy A; Shadwick, Robert E; Krysl, Petr; St Leger, Judy A; Hildebrand, John A

    2008-04-01

    This study uses remote imaging technology to quantify, compare, and contrast the cephalic anatomy between a neonate female and a young adult male Cuvier's beaked whale. Primary results reveal details of anatomic geometry with implications for acoustic function and diving. Specifically, we describe the juxtaposition of the large pterygoid sinuses, a fibrous venous plexus, and a lipid-rich pathway that connects the acoustic environment to the bony ear complex. We surmise that the large pterygoid air sinuses are essential adaptations for maintaining acoustic isolation and auditory acuity of the ears at depth. In the adult male, an acoustic waveguide lined with pachyosteosclerotic bones is apparently part of a novel transmission pathway for outgoing biosonar signals. Substitution of dense tissue boundaries where we normally find air sacs in delphinoids appears to be a recurring theme in deep-diving beaked whales and sperm whales. The anatomic configuration of the adult male Ziphius forehead resembles an upside-down sperm whale nose and may be its functional equivalent, but the homologous relationships between forehead structures are equivocal.

  3. First direct measurements of behavioural responses by Cuvier's beaked whales to mid-frequency active sonar

    PubMed Central

    DeRuiter, Stacy L.; Southall, Brandon L.; Calambokidis, John; Zimmer, Walter M. X.; Sadykova, Dinara; Falcone, Erin A.; Friedlaender, Ari S.; Joseph, John E.; Moretti, David; Schorr, Gregory S.; Thomas, Len; Tyack, Peter L.

    2013-01-01

    Most marine mammal­ strandings coincident with naval sonar exercises have involved Cuvier's beaked whales (Ziphius cavirostris). We recorded animal movement and acoustic data on two tagged Ziphius and obtained the first direct measurements of behavioural responses of this species to mid-frequency active (MFA) sonar signals. Each recording included a 30-min playback (one 1.6-s simulated MFA sonar signal repeated every 25 s); one whale was also incidentally exposed to MFA sonar from distant naval exercises. Whales responded strongly to playbacks at low received levels (RLs; 89–127 dB re 1 µPa): after ceasing normal fluking and echolocation, they swam rapidly, silently away, extending both dive duration and subsequent non-foraging interval. Distant sonar exercises (78–106 dB re 1 µPa) did not elicit such responses, suggesting that context may moderate reactions. The observed responses to playback occurred at RLs well below current regulatory thresholds; equivalent responses to operational sonars could elevate stranding risk and reduce foraging efficiency. PMID:23825085

  4. Echolocation clicks of free-ranging Cuvier's beaked whales (Ziphius cavirostris).

    PubMed

    Zimmer, Walter M X; Johnson, Mark P; Madsen, Peter T; Tyack, Peter L

    2005-06-01

    Strandings of beaked whales of the genera Ziphius and Mesoplodon have been reported to occur in conjunction with naval sonar use. Detection of the sounds from these elusive whales could reduce the risk of exposure, but descriptions of their vocalizations are at best incomplete. This paper reports quantitative characteristics of clicks from deep-diving Cuvier's beaked whales (Ziphius cavirostris) using a unique data set. Two whales in the Ligurian Sea were simultaneously tagged with sound and orientation recording tags, and the dive tracks were reconstructed allowing for derivation of the range and relative aspect between the clicking whales. At depth, the whales produced trains of regular echolocation clicks with mean interclick intervals of 0.43 s (+/- 0.09) and 0.40 s (+/- 0.07). The clicks are frequency modulated pulses with durations of approximately 200 micros and center frequencies around 42 kHz, -10 dB bandwidths of 22 kHz, and Q(3 dB) of 4. The sound beam is narrow with an estimated directionality index of more than 25 dB, source levels up to 214 dB(pp) re: 1 microPa at 1 m, and energy flux density of 164 dB re: 1 microPa2 s. As the spectral and temporal properties are different from those of nonziphiid odontocetes the potential for passive detection is enhanced.

  5. Acoustic pathways revealed: simulated sound transmission and reception in Cuvier's beaked whale (Ziphius cavirostris).

    PubMed

    Cranford, Ted W; Krysl, Petr; Hildebrand, John A

    2008-03-01

    The finite element modeling (FEM) space reported here contains the head of a simulated whale based on CT data sets as well as physical measurements of sound-propagation characteristics of actual tissue samples. Simulated sound sources placed inside and outside of an adult male Cuvier's beaked whale (Ziphius cavirostris) reveal likely sound propagation pathways into and out of the head. Two separate virtual sound sources that were located at the left and right phonic lips produced beams that converged just outside the head. This result supports the notion that dual sound sources can interfere constructively to form a biologically useful and, in fact, excellent sonar beam in front of the animal. The most intriguing FEM results concern pathways by which sounds reach the ears. The simulations reveal a previously undescribed 'gular pathway' for sound reception in Ziphius. Propagated sound pressure waves enter the head from below and between the lower jaws, pass through an opening created by the absence of the medial bony wall of the posterior mandibles, and continue toward the bony ear complexes through the internal mandibular fat bodies. This new pathway has implications for understanding the evolution of underwater hearing in odontocetes. Our model also provides evidence for receive beam directionality, off-axis acoustic shadowing and a plausible mechanism for the long-standing orthodox sound reception pathway in odontocetes. The techniques developed for this study can be used to study acoustic perturbation in a wide variety of marine organisms.

  6. Echolocation clicks of free-ranging Cuvier's beaked whales (Ziphius cavirostris)

    NASA Astrophysics Data System (ADS)

    Zimmer, Walter M. X.; Johnson, Mark P.; Madsen, Peter T.; Tyack, Peter L.

    2005-06-01

    Strandings of beaked whales of the genera Ziphius and Mesoplodon have been reported to occur in conjunction with naval sonar use. Detection of the sounds from these elusive whales could reduce the risk of exposure, but descriptions of their vocalizations are at best incomplete. This paper reports quantitative characteristics of clicks from deep-diving Cuvier's beaked whales (Ziphius cavirostris) using a unique data set. Two whales in the Ligurian Sea were simultaneously tagged with sound and orientation recording tags, and the dive tracks were reconstructed allowing for derivation of the range and relative aspect between the clicking whales. At depth, the whales produced trains of regular echolocation clicks with mean interclick intervals of 0.43 s (+/-0.09) and 0.40 s (+/-0.07). The clicks are frequency modulated pulses with durations of ~200 μs and center frequencies around 42 kHz, -10 dB bandwidths of 22 kHz, and Q3 dB of 4. The sound beam is narrow with an estimated directionality index of more than 25 dB, source levels up to 214 dBpp re: 1 μPa at 1 m, and energy flux density of 164 dB re: 1 μPa2 s. As the spectral and temporal properties are different from those of nonziphiid odontocetes the potential for passive detection is enhanced. .

  7. Better Fitness in Captive Cuvier's Gazelle despite Inbreeding Increase: Evidence of Purging?

    PubMed

    Moreno, Eulalia; Pérez-González, Javier; Carranza, Juan; Moya-Laraño, Jordi

    2015-01-01

    Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive population of Cuvier's gazelle managed under a European Endangered Species Programme since 1975. Previous results in this population have shown that highly inbred mothers tend to produce more daughters, and this fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as surplus individuals in the population). Here, by using studbook data we explore whether purging has occurred in the population by investigating whether after the change in pairing strategy a) inbreeding and homozygosity increased at the population level, b) fitness (survival) increased, and c) the relationship between inbreeding and juvenile survival, was positive. Consistent with the existence of purging, we found an increase in inbreeding coefficients, homozygosity and juvenile survival. In addition, we showed that in the course of the breeding programme the relationship between inbreeding and juvenile survival was not uniform but rather changed over time: it was negative in the early years, flat in the middle years and positive after the change in pairing strategy. We highlight that by allowing inbred individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable managing strategy to reduce the surplus of males that force most zoos to use ethical culling and euthanizing management tools. We discuss these possibilities but also acknowledge that many other effects

  8. Vertical movement patterns and ontogenetic niche expansion in the tiger shark, Galeocerdo cuvier.

    PubMed

    Afonso, André S; Hazin, Fábio H V

    2015-01-01

    Sharks are top predators in many marine ecosystems and can impact community dynamics, yet many shark populations are undergoing severe declines primarily due to overfishing. Obtaining species-specific knowledge on shark spatial ecology is important to implement adequate management strategies for the effective conservation of these taxa. This is particularly relevant concerning highly-mobile species that use wide home ranges comprising coastal and oceanic habitats, such as tiger sharks, Galeocerdo cuvier. We deployed satellite tags in 20 juvenile tiger sharks off northeastern Brazil to assess the effect of intrinsic and extrinsic factors on depth and temperature usage. Sharks were tracked for a total of 1184 d and used waters up to 1112 m in depth. The minimum temperature recorded equaled 4°C. All sharks had a clear preference for surface (< 5 m) waters but variability in depth usage was observed as some sharks used mostly shallow (< 60 m) waters whereas others made frequent incursions into greater depths. A diel behavioral shift was detected, with sharks spending considerably more time in surface (< 10 m) waters during the night. Moreover, a clear ontogenetic expansion in the vertical range of tiger shark habitat was observed, with generalized linear models estimating a ~4-fold increase in maximum diving depth from 150- to 300-cm size-classes. The time spent in the upper 5 m of the water column did not vary ontogenetically but shark size was the most important factor explaining the utilization of deeper water layers. Young-of-the-year tiger sharks seem to associate with shallow, neritic habitats but they progressively move into deeper oceanic habitats as they grow larger. Such an early plasticity in habitat use could endow tiger sharks with access to previously unavailable prey, thus contributing to a wider ecological niche. PMID:25629732

  9. Fear factor: do dugongs (Dugong dugon) trade food for safety from tiger sharks (Galeocerdo cuvier)?

    PubMed

    Wirsing, Aaron J; Heithaus, Michael R; Dill, Lawrence M

    2007-10-01

    Predators can influence plants indirectly by altering spatial patterns of herbivory, so studies assessing the relationship between perceived predation risk and habitat use by herbivores may improve our understanding of community organization. In marine systems, the effects of predation danger on space use by large herbivores have received little attention, despite the possibility that predator-mediated alterations in patterns of grazing by these animals influence benthic community structure. We evaluated the relationship between habitat use by foraging dugongs (Dugong dugon) and the threat of tiger shark predation in an Australian embayment (Shark Bay) between 1997 and 2004. Dugong densities were quantified in shallow (putatively dangerous) and deep (putatively safe) habitats (seven survey zones allocated to each habitat), and predation hazard was indexed using catch rates of tiger sharks (Galeocerdo cuvier); seagrass volume provided a measure of food biomass within each zone. Overall, dugongs selected shallow habitats, where their food is concentrated. Foragers used shallow and deep habitats in proportion to food availability (input matching) when large tiger sharks were scarce and overused deep habitats when sharks were common. Furthermore, strong synchrony existed between daily measures of shark abundance and the extent to which deep habitats were overused. Thus, dugongs appear to adaptively manage their risk of death by allocating time to safe but impoverished foraging patches in proportion to the likelihood of encountering predators in profitable but more dangerous areas. This apparent food-safety trade-off has important implications for seagrass community structure in Shark Bay, as it may result in marked temporal variability in grazing pressure.

  10. Better Fitness in Captive Cuvier's Gazelle despite Inbreeding Increase: Evidence of Purging?

    PubMed

    Moreno, Eulalia; Pérez-González, Javier; Carranza, Juan; Moya-Laraño, Jordi

    2015-01-01

    Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive population of Cuvier's gazelle managed under a European Endangered Species Programme since 1975. Previous results in this population have shown that highly inbred mothers tend to produce more daughters, and this fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as surplus individuals in the population). Here, by using studbook data we explore whether purging has occurred in the population by investigating whether after the change in pairing strategy a) inbreeding and homozygosity increased at the population level, b) fitness (survival) increased, and c) the relationship between inbreeding and juvenile survival, was positive. Consistent with the existence of purging, we found an increase in inbreeding coefficients, homozygosity and juvenile survival. In addition, we showed that in the course of the breeding programme the relationship between inbreeding and juvenile survival was not uniform but rather changed over time: it was negative in the early years, flat in the middle years and positive after the change in pairing strategy. We highlight that by allowing inbred individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable managing strategy to reduce the surplus of males that force most zoos to use ethical culling and euthanizing management tools. We discuss these possibilities but also acknowledge that many other effects

  11. Growth and Maximum Size of Tiger Sharks (Galeocerdo cuvier) in Hawaii

    PubMed Central

    Meyer, Carl G.; O'Malley, Joseph M.; Papastamatiou, Yannis P.; Dale, Jonathan J.; Hutchinson, Melanie R.; Anderson, James M.; Royer, Mark A.; Holland, Kim N.

    2014-01-01

    Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13′17″N 109°52′14″W), in the southern Gulf of California (minimum distance between tag and recapture sites  =  approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates. PMID:24416287

  12. Reef-fidelity and migration of tiger sharks, Galeocerdo cuvier, across the Coral Sea.

    PubMed

    Werry, Jonathan M; Planes, Serge; Berumen, Michael L; Lee, Kate A; Braun, Camrin D; Clua, Eric

    2014-01-01

    Knowledge of the habitat use and migration patterns of large sharks is important for assessing the effectiveness of large predator Marine Protected Areas (MPAs), vulnerability to fisheries and environmental influences, and management of shark-human interactions. Here we compare movement, reef-fidelity, and ocean migration for tiger sharks, Galeocerdo cuvier, across the Coral Sea, with an emphasis on New Caledonia. Thirty-three tiger sharks (1.54 to 3.9 m total length) were tagged with passive acoustic transmitters and their localised movements monitored on receiver arrays in New Caledonia, the Chesterfield and Lord Howe Islands in the Coral Sea, and the east coast of Queensland, Australia. Satellite tags were also used to determine habitat use and movements among habitats across the Coral Sea. Sub-adults and one male adult tiger shark displayed year-round residency in the Chesterfields with two females tagged in the Chesterfields and detected on the Great Barrier Reef, Australia, after 591 and 842 days respectively. In coastal barrier reefs, tiger sharks were transient at acoustic arrays and each individual demonstrated a unique pattern of occurrence. From 2009 to 2013, fourteen sharks with satellite and acoustic tags undertook wide-ranging movements up to 1114 km across the Coral Sea with eight detected back on acoustic arrays up to 405 days after being tagged. Tiger sharks dove 1136 m and utilised three-dimensional activity spaces averaged at 2360 km³. The Chesterfield Islands appear to be important habitat for sub-adults and adult male tiger sharks. Management strategies need to consider the wide-ranging movements of large (sub-adult and adult) male and female tiger sharks at the individual level, whereas fidelity to specific coastal reefs may be consistent across groups of individuals. Coastal barrier reef MPAs, however, only afford brief protection for large tiger sharks, therefore determining the importance of other oceanic Coral Sea reefs should be a

  13. Vertical movement patterns and ontogenetic niche expansion in the tiger shark, Galeocerdo cuvier.

    PubMed

    Afonso, André S; Hazin, Fábio H V

    2015-01-01

    Sharks are top predators in many marine ecosystems and can impact community dynamics, yet many shark populations are undergoing severe declines primarily due to overfishing. Obtaining species-specific knowledge on shark spatial ecology is important to implement adequate management strategies for the effective conservation of these taxa. This is particularly relevant concerning highly-mobile species that use wide home ranges comprising coastal and oceanic habitats, such as tiger sharks, Galeocerdo cuvier. We deployed satellite tags in 20 juvenile tiger sharks off northeastern Brazil to assess the effect of intrinsic and extrinsic factors on depth and temperature usage. Sharks were tracked for a total of 1184 d and used waters up to 1112 m in depth. The minimum temperature recorded equaled 4°C. All sharks had a clear preference for surface (< 5 m) waters but variability in depth usage was observed as some sharks used mostly shallow (< 60 m) waters whereas others made frequent incursions into greater depths. A diel behavioral shift was detected, with sharks spending considerably more time in surface (< 10 m) waters during the night. Moreover, a clear ontogenetic expansion in the vertical range of tiger shark habitat was observed, with generalized linear models estimating a ~4-fold increase in maximum diving depth from 150- to 300-cm size-classes. The time spent in the upper 5 m of the water column did not vary ontogenetically but shark size was the most important factor explaining the utilization of deeper water layers. Young-of-the-year tiger sharks seem to associate with shallow, neritic habitats but they progressively move into deeper oceanic habitats as they grow larger. Such an early plasticity in habitat use could endow tiger sharks with access to previously unavailable prey, thus contributing to a wider ecological niche.

  14. Growth and maximum size of tiger sharks (Galeocerdo cuvier) in Hawaii.

    PubMed

    Meyer, Carl G; O'Malley, Joseph M; Papastamatiou, Yannis P; Dale, Jonathan J; Hutchinson, Melanie R; Anderson, James M; Royer, Mark A; Holland, Kim N

    2014-01-01

    Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13'17″N 109°52'14″W), in the southern Gulf of California (minimum distance between tag and recapture sites  =  approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates.

  15. Vertical Movement Patterns and Ontogenetic Niche Expansion in the Tiger Shark, Galeocerdo cuvier

    PubMed Central

    Afonso, André S.; Hazin, Fábio H. V.

    2015-01-01

    Sharks are top predators in many marine ecosystems and can impact community dynamics, yet many shark populations are undergoing severe declines primarily due to overfishing. Obtaining species-specific knowledge on shark spatial ecology is important to implement adequate management strategies for the effective conservation of these taxa. This is particularly relevant concerning highly-mobile species that use wide home ranges comprising coastal and oceanic habitats, such as tiger sharks, Galeocerdo cuvier. We deployed satellite tags in 20 juvenile tiger sharks off northeastern Brazil to assess the effect of intrinsic and extrinsic factors on depth and temperature usage. Sharks were tracked for a total of 1184 d and used waters up to 1112 m in depth. The minimum temperature recorded equaled 4°C. All sharks had a clear preference for surface (< 5 m) waters but variability in depth usage was observed as some sharks used mostly shallow (< 60 m) waters whereas others made frequent incursions into greater depths. A diel behavioral shift was detected, with sharks spending considerably more time in surface (< 10 m) waters during the night. Moreover, a clear ontogenetic expansion in the vertical range of tiger shark habitat was observed, with generalized linear models estimating a ~4-fold increase in maximum diving depth from 150- to 300-cm size-classes. The time spent in the upper 5 m of the water column did not vary ontogenetically but shark size was the most important factor explaining the utilization of deeper water layers. Young-of-the-year tiger sharks seem to associate with shallow, neritic habitats but they progressively move into deeper oceanic habitats as they grow larger. Such an early plasticity in habitat use could endow tiger sharks with access to previously unavailable prey, thus contributing to a wider ecological niche. PMID:25629732

  16. Reef-Fidelity and Migration of Tiger Sharks, Galeocerdo cuvier, across the Coral Sea

    PubMed Central

    Werry, Jonathan M.; Planes, Serge; Berumen, Michael L.; Lee, Kate A.; Braun, Camrin D.; Clua, Eric

    2014-01-01

    Knowledge of the habitat use and migration patterns of large sharks is important for assessing the effectiveness of large predator Marine Protected Areas (MPAs), vulnerability to fisheries and environmental influences, and management of shark–human interactions. Here we compare movement, reef-fidelity, and ocean migration for tiger sharks, Galeocerdo cuvier, across the Coral Sea, with an emphasis on New Caledonia. Thirty-three tiger sharks (1.54 to 3.9 m total length) were tagged with passive acoustic transmitters and their localised movements monitored on receiver arrays in New Caledonia, the Chesterfield and Lord Howe Islands in the Coral Sea, and the east coast of Queensland, Australia. Satellite tags were also used to determine habitat use and movements among habitats across the Coral Sea. Sub-adults and one male adult tiger shark displayed year-round residency in the Chesterfields with two females tagged in the Chesterfields and detected on the Great Barrier Reef, Australia, after 591 and 842 days respectively. In coastal barrier reefs, tiger sharks were transient at acoustic arrays and each individual demonstrated a unique pattern of occurrence. From 2009 to 2013, fourteen sharks with satellite and acoustic tags undertook wide-ranging movements up to 1114 km across the Coral Sea with eight detected back on acoustic arrays up to 405 days after being tagged. Tiger sharks dove 1136 m and utilised three-dimensional activity spaces averaged at 2360 km3. The Chesterfield Islands appear to be important habitat for sub-adults and adult male tiger sharks. Management strategies need to consider the wide-ranging movements of large (sub-adult and adult) male and female tiger sharks at the individual level, whereas fidelity to specific coastal reefs may be consistent across groups of individuals. Coastal barrier reef MPAs, however, only afford brief protection for large tiger sharks, therefore determining the importance of other oceanic Coral Sea reefs should be a

  17. Cuvier's beaked whale (Ziphius cavirostris) head tissues: physical properties and CT imaging.

    PubMed

    Soldevilla, Melissa S; McKenna, Megan F; Wiggins, Sean M; Shadwick, Robert E; Cranford, Ted W; Hildebrand, John A

    2005-06-01

    Tissue physical properties from a Cuvier's beaked whale (Ziphius cavirostris) neonate head are reported and compared with computed tomography (CT) X-ray imaging. Physical properties measured include longitudinal sound velocity, density, elastic modulus and hysteresis. Tissues were classified by type as follows: mandibular acoustic fat, mandibular blubber, forehead acoustic fat (melon), forehead blubber, muscle and connective tissue. Results show that each class of tissues has unique, co-varying physical properties. The mandibular acoustic fats had minimal values for sound speed (1350+/-10.6 m s(-1)) and mass density (890+/-23 kg m(-3)). These values increased through mandibular blubber (1376+/-13 m s(-1), 919+/-13 kg m(-3)), melon (1382+/-23 m s(-1), 937+/-17 kg m(-3)), forehead blubber (1401+/-7.8 m s(-1), 935+/-25 kg m(-3)) and muscle (1517+/-46.8 m s(-1), 993+/-58 kg m(-3)). Connective tissue had the greatest mean sound speed and density (1628+/-48.7 m s(-1), 1087+/-41 kg m(-3)). The melon formed a low-density, low-sound-speed core, supporting its function as a sound focusing organ. Hounsfield unit (HU) values from CT X-ray imaging are correlated with density and sound speed values, allowing HU values to be used to predict these physical properties. Blubber and connective tissues have a higher elastic modulus than acoustic fats and melon, suggesting more collagen structure in blubber and connective tissues. Blubber tissue elastic modulus is nonlinear with varying stress, becoming more incompressible as stress is increased. These data provide important physical properties required to construct models of the sound generation and reception mechanisms in Ziphius cavirostris heads, as well as models of their interaction with anthropogenic sound.

  18. Intraspecific variation in vertical habitat use by tiger sharks (Galeocerdo cuvier) in the western North Atlantic

    PubMed Central

    Vaudo, Jeremy J; Wetherbee, Bradley M; Harvey, Guy; Nemeth, Richard S; Aming, Choy; Burnie, Neil; Howey-Jordan, Lucy A; Shivji, Mahmood S

    2014-01-01

    Tiger sharks (Galeocerdo cuvier) are a wide ranging, potentially keystone predator species that display a variety of horizontal movement patterns, making use of coastal and pelagic waters. Far less, however, is known about their vertical movements and use of the water column. We used pop-up satellite archival tags with two data sampling rates (high rate and standard rate tags) to investigate the vertical habitat use and diving behavior of tiger sharks tagged on the Puerto Rico–Virgin Islands platform and off Bermuda between 2008 and 2009. Useable data were received from nine of 14 sharks tagged, tracked over a total of 529 days. Sharks spent the majority of their time making yo-yo dives within the upper 50 m of the water column and considerable time within the upper 5 m of the water column. As a result, sharks typically occupied a narrow daily temperature range (∼2°C). Dives to greater than 200 m were common, and all sharks made dives to at least 250 m, with one shark reaching a depth of 828 m. Despite some similarities among individuals, a great deal of intraspecific variability in vertical habit use was observed. Four distinct depth distributions that were not related to tagging location, horizontal movements, sex, or size were detected. In addition, similar depth distributions did not necessitate similar dive patterns among sharks. Recognition of intraspecific variability in habitat use of top predators can be crucial for effective management of these species and for understanding their influence on ecosystem dynamics. PMID:24963376

  19. Gouge marks on deep-sea mud volcanoes in the eastern Mediterranean: Caused by Cuvier's beaked whales?

    NASA Astrophysics Data System (ADS)

    Woodside, J. M.; David, L.; Frantzis, A.; Hooker, S. K.

    2006-11-01

    Enigmatic seafloor gouge marks at depths of 1700-2100 m have been observed from submersible during geological survey work studying mud volcanoes in the eastern Mediterranean Sea. The marks consist of a central groove (about 10 cm deep and 1-2 m long), superimposed on a broader bowl-shaped depression (1-2 m long by about 50 cm wide) with raised rims (up to 10 cm high) to either side of the central groove. We discuss the potential biological causes of these marks, and conclude that they are probably created by Cuvier's beaked whales ( Ziphius cavirostris) during foraging dives to these depths. The mud volcanoes have a comparatively rich and diverse benthic ecology associated with methane-rich fluid seeps and thus could be the base of food chains that reach top predators like the deep-diving whales. The characteristic high acoustic backscatter of the mud volcanoes would facilitate their detection by the echolocation system of these whales.

  20. Women peers in the scientific realm: Sarah Bowdich (Lee)'s expert collaborations with Georges Cuvier, 1825–33

    PubMed Central

    Orr, Mary

    2015-01-01

    The accepted rule for women contributing to nineteenth-century science before 1851 was that they could play only secondary roles in its production and authorship—as translators, illustrators, popularizers—and these by virtue of kinship or marriage to eminent scientists in the field or the laboratory. Sarah Bowdich (Lee) (1791–1856) presents an important amendment to this rule. As an explorer of West Africa on an equal scientific footing with her husband, and then a writer of science independently after his early death, she had other key roles as Georges Cuvier's cross-Channel scientific collaborator and as his first biographer. This article investigates and reframes Sarah's many individual achievements in science and its writing, to examine the larger questions of her case. How were her publications and ‘uneasy career’ in science possible? Can research on women in science today find inspiration in her example? PMID:26489182

  1. Worldwide structure of mtDNA diversity among Cuvier's beaked whales (Ziphius cavirostris): implications for threatened populations.

    PubMed

    Dalebout, Merel L; Robertson, Kelly M; Frantzis, Alexandros; Engelhaupt, Dan; Mignucci-Giannoni, Antonio A; Rosario-Delestre, Raul J; Baker, C Scott

    2005-10-01

    We present the first description of phylogeographic structure among Cuvier's beaked whales (Ziphius cavirostris) worldwide using mitochondrial DNA (mtDNA) control region sequences obtained from strandings (n = 70), incidental fisheries takes (n = 11), biopsy (n = 1), and whale-meat markets (n = 5). Over a 290-base pair fragment, 23 variable sites defined 33 unique haplotypes among the total of 87 samples. Nucleotide diversity at the control region was relatively low (pi = 1.27%+/- 0.723%) compared to wide-ranging baleen whales, but higher than strongly matrifocal sperm, pilot and killer whales. Phylogenetic reconstruction using maximum likelihood revealed four distinct haplotype groups, each of which displayed strong frequency differences among ocean basins, but no reciprocal monophyly or fixed character differences. Consistent with this phylogeographic pattern, an analysis of molecular variance showed high levels of differentiation among ocean basins (F(ST) = 0.14, Phi ST = 0.42; P < 0.001). Estimated rates of female migration among ocean basins were low (generally < or = 2 individuals per generation). Regional sample sizes were too small to detect subdivisions within oceans except in the North Atlantic, where the Mediterranean Sea (n = 12) was highly differentiated due to the presence of two private haplotypes. One market product purchased in South Korea grouped with other haplotypes found only in the North Atlantic, suggesting a violation of current agreements banning international trade in cetacean species. Together, these results demonstrate a high degree of isolation and low maternal gene flow among oceanic, and in some cases, regional populations of Cuvier's beaked whales. This has important implications for understanding the threats of human impact, including fisheries by-catch, direct hunting, and disturbance or mortality from anthropogenic sound. PMID:16156808

  2. Worldwide structure of mtDNA diversity among Cuvier's beaked whales (Ziphius cavirostris): implications for threatened populations.

    PubMed

    Dalebout, Merel L; Robertson, Kelly M; Frantzis, Alexandros; Engelhaupt, Dan; Mignucci-Giannoni, Antonio A; Rosario-Delestre, Raul J; Baker, C Scott

    2005-10-01

    We present the first description of phylogeographic structure among Cuvier's beaked whales (Ziphius cavirostris) worldwide using mitochondrial DNA (mtDNA) control region sequences obtained from strandings (n = 70), incidental fisheries takes (n = 11), biopsy (n = 1), and whale-meat markets (n = 5). Over a 290-base pair fragment, 23 variable sites defined 33 unique haplotypes among the total of 87 samples. Nucleotide diversity at the control region was relatively low (pi = 1.27%+/- 0.723%) compared to wide-ranging baleen whales, but higher than strongly matrifocal sperm, pilot and killer whales. Phylogenetic reconstruction using maximum likelihood revealed four distinct haplotype groups, each of which displayed strong frequency differences among ocean basins, but no reciprocal monophyly or fixed character differences. Consistent with this phylogeographic pattern, an analysis of molecular variance showed high levels of differentiation among ocean basins (F(ST) = 0.14, Phi ST = 0.42; P < 0.001). Estimated rates of female migration among ocean basins were low (generally < or = 2 individuals per generation). Regional sample sizes were too small to detect subdivisions within oceans except in the North Atlantic, where the Mediterranean Sea (n = 12) was highly differentiated due to the presence of two private haplotypes. One market product purchased in South Korea grouped with other haplotypes found only in the North Atlantic, suggesting a violation of current agreements banning international trade in cetacean species. Together, these results demonstrate a high degree of isolation and low maternal gene flow among oceanic, and in some cases, regional populations of Cuvier's beaked whales. This has important implications for understanding the threats of human impact, including fisheries by-catch, direct hunting, and disturbance or mortality from anthropogenic sound.

  3. Effect of egg yolk, cryoprotectant, and various sugars on semen cryopreservation in endangered Cuvier's gazelle (Gazella cuvieri).

    PubMed

    Garde, J J; del Olmo, A; Soler, A J; Espeso, G; Gomendio, M; Roldan, E R S

    2008-11-01

    Cryopreservation of spermatozoa from endangered species is a valuable tool for genetic management. Previous studies showed the feasibility of cryopreservation of spermatozoa from various endangered gazelles but have also revealed difficulties with available protocols for semen freezing in Cuvier's gazelle (Gazella cuvieri). Experiments were carried out to investigate the effect of (a) 5% or 20% egg yolk or 4% or 6% glycerol, and (b) addition of sugars (glucose, fructose, lactose and raffinose) on cryopreservation using a Tes-Tris-based diluent (TEST). A diluent containing 13.5% raffinose, 5% or 20% egg yolk, and 6% glycerol (REYG) was also evaluated. Semen was obtained by electroejaculation from 22 G. cuvieri males. Diluted samples were loaded into 0.25 ml straws, cooled to 5 degrees C over 1.5h (-0.16 degrees C/min), equilibrated at that temperature for 2h, frozen in nitrogen vapours for 10 min and plunged into liquid nitrogen. Subsamples were assessed for motility and acrosome integrity upon collection, after refrigeration-equilibration, after freezing and thawing, and 2h after thawing. Use of TEST with 20% egg yolk or with 4% glycerol led to worse motility preservation, whereas TEST with 5% egg yolk and 6% glycerol led to better results. Addition of fructose, lactose or raffinose to TEST resulted in similar or worse preservation of motility than inclusion of glucose. On the other hand, use of a raffinose-based medium with 20% egg yolk and 6% glycerol (REYG) afforded better preservation of motility than use of TEST. With REYG, 20% egg yolk was better than 5% egg yolk for motility preservation. Differences were noted between males in their responses to cryopreservation when using different egg yolk or glycerol concentrations. Moreover, spermatozoa from most males exhibited better cryopreservation with REYG although some were better cryopreserved in TEST. The raffinose-based diluent thus represents an improvement over previous results but more work is needed to

  4. First long-term behavioral records from Cuvier's beaked whales (Ziphius cavirostris) reveal record-breaking dives.

    PubMed

    Schorr, Gregory S; Falcone, Erin A; Moretti, David J; Andrews, Russel D

    2014-01-01

    Cuvier's beaked whales (Ziphius cavirostris) are known as extreme divers, though behavioral data from this difficult-to-study species have been limited. They are also the species most often stranded in association with Mid-Frequency Active (MFA) sonar use, a relationship that remains poorly understood. We used satellite-linked tags to record the diving behavior and locations of eight Ziphius off the Southern California coast for periods up to three months. The effort resulted in 3732 hr of dive data with associated regional movements--the first dataset of its kind for any beaked whale--and included dives to 2992 m depth and lasting 137.5 min, both new mammalian dive records. Deep dives had a group mean depth of 1401 m (s.d. = 137.8, n = 1142) and duration of 67.4 min (s.d. = 6.9). The group mean time between deep dives was 102.3 min (s.d. = 30.8, n = 783). While the previously described stereotypic pattern of deep and shallow dives was apparent, there was considerable inter- and intra-individual variability in most parameters. There was significant diel behavioral variation, including increased time near the surface and decreased shallow diving at night. However, maximum depth and the proportion of time spent on deep dives (presumed foraging), varied little from day to night. Surprisingly, tagged whales were present within an MFA sonar training range for 38% of days locations were received, and though comprehensive records of sonar use during tag deployments were not available, we discuss the effects frequent acoustic disturbance may have had on the observed behaviors. These data better characterize the true behavioral range of this species, and suggest caution should be exercised when drawing conclusions about behavior using short-term datasets.

  5. Ontogeny of head and caudal fin shape of an apex marine predator: The tiger shark (Galeocerdo cuvier).

    PubMed

    Fu, Amy L; Hammerschlag, Neil; Lauder, George V; Wilga, Cheryl D; Kuo, Chi-Yun; Irschick, Duncan J

    2016-05-01

    How morphology changes with size can have profound effects on the life history and ecology of an animal. For apex predators that can impact higher level ecosystem processes, such changes may have consequences for other species. Tiger sharks (Galeocerdo cuvier) are an apex predator in tropical seas, and, as adults, are highly migratory. However, little is known about ontogenetic changes in their body form, especially in relation to two aspects of shape that influence locomotion (caudal fin) and feeding (head shape). We captured digital images of the heads and caudal fins of live tiger sharks from Southern Florida and the Bahamas ranging in body size (hence age), and quantified shape of each using elliptical Fourier analysis. This revealed changes in the shape of the head and caudal fin of tiger sharks across ontogeny. Smaller juvenile tiger sharks show an asymmetrical tail with the dorsal (upper) lobe being substantially larger than the ventral (lower) lobe, and transition to more symmetrical tail in larger adults, although the upper lobe remains relatively larger in adults. The heads of juvenile tiger sharks are more conical, which transition to relatively broader heads over ontogeny. We interpret these changes as a result of two ecological transitions. First, adult tiger sharks can undertake extensive migrations and a more symmetrical tail could be more efficient for swimming longer distances, although we did not test this possibility. Second, adult tiger sharks expand their diet to consume larger and more diverse prey with age (turtles, mammals, and elasmobranchs), which requires substantially greater bite area and force to process. In contrast, juvenile tiger sharks consume smaller prey, such as fishes, crustaceans, and invertebrates. Our data reveal significant morphological shifts in an apex predator, which could have effects for other species that tiger sharks consume and interact with.

  6. Ontogeny of head and caudal fin shape of an apex marine predator: The tiger shark (Galeocerdo cuvier).

    PubMed

    Fu, Amy L; Hammerschlag, Neil; Lauder, George V; Wilga, Cheryl D; Kuo, Chi-Yun; Irschick, Duncan J

    2016-05-01

    How morphology changes with size can have profound effects on the life history and ecology of an animal. For apex predators that can impact higher level ecosystem processes, such changes may have consequences for other species. Tiger sharks (Galeocerdo cuvier) are an apex predator in tropical seas, and, as adults, are highly migratory. However, little is known about ontogenetic changes in their body form, especially in relation to two aspects of shape that influence locomotion (caudal fin) and feeding (head shape). We captured digital images of the heads and caudal fins of live tiger sharks from Southern Florida and the Bahamas ranging in body size (hence age), and quantified shape of each using elliptical Fourier analysis. This revealed changes in the shape of the head and caudal fin of tiger sharks across ontogeny. Smaller juvenile tiger sharks show an asymmetrical tail with the dorsal (upper) lobe being substantially larger than the ventral (lower) lobe, and transition to more symmetrical tail in larger adults, although the upper lobe remains relatively larger in adults. The heads of juvenile tiger sharks are more conical, which transition to relatively broader heads over ontogeny. We interpret these changes as a result of two ecological transitions. First, adult tiger sharks can undertake extensive migrations and a more symmetrical tail could be more efficient for swimming longer distances, although we did not test this possibility. Second, adult tiger sharks expand their diet to consume larger and more diverse prey with age (turtles, mammals, and elasmobranchs), which requires substantially greater bite area and force to process. In contrast, juvenile tiger sharks consume smaller prey, such as fishes, crustaceans, and invertebrates. Our data reveal significant morphological shifts in an apex predator, which could have effects for other species that tiger sharks consume and interact with. PMID:26869274

  7. Germ cell survival and differentiation after xenotransplantation of testis tissue from three endangered species: Iberian lynx (Lynx pardinus), Cuvier's gazelle (Gazella cuvieri) and Mohor gazelle (G. dama mhorr).

    PubMed

    Arregui, Lucía; Dobrinski, Ina; Roldan, Eduardo R S

    2014-01-01

    The use of assisted reproductive techniques for endangered species is a major goal for conservation. One of these techniques, testis tissue xenografting, allows for the development of spermatozoa from animals that die before reaching sexual maturity. To assess the potential use of this technique with endangered species, testis tissue from six Iberian lynxes (one fetus, two perinatal cubs, two 6-month-old and one 2-year-old lynx), two Cuvier's gazelle fetuses and one 8-month-old Mohor gazelle were transplanted ectopically into nude mice. Tissue from the lynx fetus, perinatal cubs and 2-year-old donors degenerated, whereas spermatogonia were present in 15% of seminiferous tubules more than 70 weeks after grafting in transplanted testis tissue from 6-month-old donors. Seminal vesicle weights (indicative of testosterone production) increased over time in mice transplanted with tissue from 6-month-old lynxes. Progression of spermatogenesis was observed in xenografts from gazelles and was donor age dependent. Tissue from Cuvier's gazelle fetuses contained spermatocytes 40 weeks after grafting. Finally, round spermatids were found 28 weeks after transplantation in grafts from the 8-month-old Mohor gazelle. This is the first time that xenotransplantation of testicular tissue has been performed with an endangered felid and the first successful xenotransplantation in an endangered species. Our results open important options for the preservation of biological diversity. PMID:23763851

  8. Germ cell survival and differentiation after xenotransplantation of testis tissue from three endangered species: Iberian lynx (Lynx pardinus), Cuvier's gazelle (Gazella cuvieri) and Mohor gazelle (G. dama mhorr).

    PubMed

    Arregui, Lucía; Dobrinski, Ina; Roldan, Eduardo R S

    2014-01-01

    The use of assisted reproductive techniques for endangered species is a major goal for conservation. One of these techniques, testis tissue xenografting, allows for the development of spermatozoa from animals that die before reaching sexual maturity. To assess the potential use of this technique with endangered species, testis tissue from six Iberian lynxes (one fetus, two perinatal cubs, two 6-month-old and one 2-year-old lynx), two Cuvier's gazelle fetuses and one 8-month-old Mohor gazelle were transplanted ectopically into nude mice. Tissue from the lynx fetus, perinatal cubs and 2-year-old donors degenerated, whereas spermatogonia were present in 15% of seminiferous tubules more than 70 weeks after grafting in transplanted testis tissue from 6-month-old donors. Seminal vesicle weights (indicative of testosterone production) increased over time in mice transplanted with tissue from 6-month-old lynxes. Progression of spermatogenesis was observed in xenografts from gazelles and was donor age dependent. Tissue from Cuvier's gazelle fetuses contained spermatocytes 40 weeks after grafting. Finally, round spermatids were found 28 weeks after transplantation in grafts from the 8-month-old Mohor gazelle. This is the first time that xenotransplantation of testicular tissue has been performed with an endangered felid and the first successful xenotransplantation in an endangered species. Our results open important options for the preservation of biological diversity.

  9. A PUFFERFISH (TETRADON NIGROVIRIDIS) AVAILABLE IN THE COMMON PET TRADE HARBORS LETHAL CONCENTRATIONS OF TETRODOTOXIN: A CASE STUDY OF POISONING IN A CUVIER'S DWARF CAIMAN (PALEOSUCHUS PALPEBROSUS).

    PubMed

    Williams, Becky L; Powers, Lauren V; Garner, Michael M

    2016-06-01

    Many pufferfish possess tetrodotoxin (TTX). Unaware of this fact, the owner of a 3-mo-old pet Cuvier's dwarf caiman ( Paleosuchus palpebrosus ) fed the caiman a green spotted pufferfish ( Tetraodon nigroviridis ), acquired from a local discount department store. The caiman was nonresponsive within an hour of consumption of the fish. The caiman was presented for veterinary evaluation but died despite intensive medical care. High-performance liquid chromatography and a competitive inhibition enzyme immunoassay were used to determine whether the pufferfish was tetrodotoxic and whether the deceased caiman had TTX in its system. Skin and liver of the pufferfish harbored high concentrations of TTX, and the caiman had TTX in the blood, liver, and kidney. The clinical signs and presence of TTX in the caiman suggest that the caiman succumbed to tetrodotoxicosis. The implication is that lethally poisonous species are available commercially and pose a danger to other pets and possibly small children.

  10. Sighting characteristics and photo-identification of Cuvier's beaked whales (Ziphius cavirostris) near San Clemente Island, California: a key area for beaked whales and the military?

    PubMed

    Falcone, Erin A; Schorr, Gregory S; Douglas, Annie B; Calambokidis, John; Henderson, Elizabeth; McKenna, Megan F; Hildebrand, John; Moretti, David

    2009-01-01

    The relationship between beaked whales and certain anthropogenic sounds remains poorly understood and of great interest. Although Cuvier's beaked whales (Ziphius cavirostris) are widely distributed, little is known of their behavior and population structure throughout much of their range. We conducted a series of five combined visual-acoustic marine mammal surveys from 2006 to 2008 in the southern San Nicolas Basin, a site of frequent naval activity off the southern California coast, west of San Clemente Island. The study area was defined by a 1,800 km(2) array of 88 bottom-mounted hydrophones at depths up to 1,850 m. The array was used to vector visual observers toward vocalizing marine mammal species. Thirty-seven groups of Cuvier's beaked whales were encountered during the study period. The overall encounter rate was one group for every 21.0 h of survey effort, and was as high as one group per 10.2 h of effort during the October 2007 survey. Whales were encountered in the deepest portion of the study area, at a mean bottom depth of 1,580 m (SD 138). The average group size was 3.8 individuals (SD 2.4), which was higher than has been reported from other studies of this species. Twenty-four groups were observed over multiple surfacings (median = 4 surfacings, range 2-15). The mean encounter duration of extended sightings was 104 min (SD 98, range 12-466 min) and the mean distance moved over the course of sightings was 1.66 km (SD 1.56, range 0.08-6.65 km). Temporal surfacing patterns during extended encounters were similar to dive behavior described from Cuvier's beaked whales carrying time-depth recording tags. Seventy-eight photographic identifications were made of 58 unique individuals, for an overall resighting rate of 0.26. Whales were sighted on up to 4 days, with duration from first to last sighting spanning 2-79 days. For those whales sighted on subsequent days, the mean distance between subsequent sightings was 8.6 km (SD 7.9). Individuals

  11. Using existing data and focused surveys to highlight Cuvier's beaked whales favourable areas: a case study in the central Tyrrhenian Sea.

    PubMed

    Gannier, Alexandre

    2011-01-01

    This study focuses on the necessary elements to implement strategic mitigation in order to avoid Cuvier's beaked whale (CBW) strandings linked to intense sound sources, such as military active sonars, in the Mediterranean Sea. A careful review of stranding data and the analysis of existing survey results are required to highlight the main characters of the species regional distribution. Focused and repeated surveys are needed to confirm that possible favourable areas, such as the Balearic, Tyrrhenian or Aegean Seas, are really favourable CBW habitats. These surveys should be carried out with sea states 0 to 1 in order to minimize the risk of false absence data. Among the regions of interest, the central Tyrrhenian Sea was surveyed with a 12 m sailboat in 2007 and 2008. With 907 km of effective effort, a mean sighting rate of 1.9 CBW school/100 km was obtained, which is amongst the highest densities recorded in the Mediterranean. PMID:20546808

  12. A PUFFERFISH (TETRADON NIGROVIRIDIS) AVAILABLE IN THE COMMON PET TRADE HARBORS LETHAL CONCENTRATIONS OF TETRODOTOXIN: A CASE STUDY OF POISONING IN A CUVIER'S DWARF CAIMAN (PALEOSUCHUS PALPEBROSUS).

    PubMed

    Williams, Becky L; Powers, Lauren V; Garner, Michael M

    2016-06-01

    Many pufferfish possess tetrodotoxin (TTX). Unaware of this fact, the owner of a 3-mo-old pet Cuvier's dwarf caiman ( Paleosuchus palpebrosus ) fed the caiman a green spotted pufferfish ( Tetraodon nigroviridis ), acquired from a local discount department store. The caiman was nonresponsive within an hour of consumption of the fish. The caiman was presented for veterinary evaluation but died despite intensive medical care. High-performance liquid chromatography and a competitive inhibition enzyme immunoassay were used to determine whether the pufferfish was tetrodotoxic and whether the deceased caiman had TTX in its system. Skin and liver of the pufferfish harbored high concentrations of TTX, and the caiman had TTX in the blood, liver, and kidney. The clinical signs and presence of TTX in the caiman suggest that the caiman succumbed to tetrodotoxicosis. The implication is that lethally poisonous species are available commercially and pose a danger to other pets and possibly small children. PMID:27468050

  13. Two new species of the genus Sitana Cuvier, 1829 (Reptilia: Agamidae) from Sri Lanka, including a taxonomic revision of the Indian Sitana species.

    PubMed

    Amarasinghe, A A Thasun; Ineich, Ivan; Karunarathna, D M S Suranjan; Botejue, W Madhava S; Campbell, Patrick D

    2015-01-01

    The genus Sitana was described by Cuvier (1829) on the basis of a single species, S. ponticeriana. The secondly described, Sitana minor Günther, 1864, is identical to S. ponticeriana Cuvier, 1829, and should be considered as a junior objective synonym of the latter. The syntypes of S. deccanensis Jerdon, 1870 have been rediscovered, misplaced among the syntypes of S. minor (sensu Boulenger 1885) at the Natural History Museum (London) and the former taxon is here recognised as a valid species and redescribed. There is some doubt surrounding the taxon Sitana ponticeriana mucronata Deraniyagala, 1957. Its type is lost and no live populations have been found since its original description; therefore, we here consider this trinomen as a nomen dubium. The Sitana populations which are distributed in drier and warmer areas of the lower peneplain of Sri Lanka are sufficiently different from the known Indian species and are thus herein described as new species. The two new species, Sitana bahiri sp. nov. and Sitana devakai sp. nov., differ from mainland Indian congeners by having the following combination of characters: SVL 40.0-50.0 mm; axilla-dewlap length 28.3-32.5% of axilla-groin length; snout length 54.7-63.2% of head width; femur length 70.6-78.4% of tibia length; foot length 154.7-180.2% of head length; 49-59 midbody scales; 87-108 ventral scales; unequal and irregular lateral scales with intermediate enlarged scales; 7-9 supralabials; 14-17 subdigital lamellae on toe III; 21-26 subdigital lamellae on toe IV; enlarged scales above the tympanum; a single pale stripe from the snout up to the shoulder. Sitana bahiri sp. nov. differs from Sitana devakai sp. nov. by having ventrals 87-89 (vs. 100-108), mucronate lateral scales (vs. rounded) in males, and rounded (vs. mucronate) ventral scales in females, plus several other characters discussed later . The remaining Sitana populations in India seem to represent several undescribed species, but extensive field work and

  14. Identification and management of ocular lipid deposition in association with hyperlipidaemia in captive moray eels, Gymnothorax funebris Ranzani, Gymnothorax moringa (Cuvier) and Muraena retifera Goode and Bean.

    PubMed

    Clode, A B; Harms, C; Fatzinger, M H; Young, F; Colitz, C; Wert, D

    2012-09-01

    Ocular lipid deposition and its surgical management and possible association with systemic hyperlipidaemia in captive moray eels are described. Ophthalmologic examinations, haematology and plasma biochemistry analyses were performed on an initial population of captive moray eels (n=10): green moray, Gymnothorax funebris Ranzani; spotted moray, Gymnothorax morninga (Cuvier) and reticulated moray, Muraena retifera Goode and Bean. Recently captured green moray eels comprised the control group (n=9). Clinical signs compatible with ocular lipid deposition were identified in six of ten captive eels (60%) vs. none of the controls. Green moray eels in the initial captive population (n=5) had significantly higher total protein, triglyceride, cholesterol and aspartate amino transferase values than the control eels. Dietary management was attempted in all captive eels, and surgical intervention was performed in three eels, including two from a separate population, with improved ocular clarity within 1month post-operatively. Histopathological evaluation of surgical specimens and two eyes from an additional affected eel that died suggested ocular lipid deposition. Eels in captivity have an apparent predisposition for hyperlipidaemia and ocular lipid deposition. Although limited in this study and complicated by exhibit restraints, dietary management was minimally effective, while surgery improved ocular clarity.

  15. Isolation and characterization of eight microsatellite loci from Galeocerdo cuvier (tiger shark) and cross-amplification in Carcharhinus leucas, Carcharhinus brevipinna, Carcharhinus plumbeus and Sphyrna lewini.

    PubMed

    Pirog, Agathe; Jaquemet, Sébastien; Blaison, Antonin; Soria, Marc; Magalon, Hélène

    2016-01-01

    The tiger shark Galeocerdo cuvier (Carcharhinidae) is a large elasmobranch suspected to have, as other apex predators, a keystone function in marine ecosystems and is currently considered Near Threatened (Red list IUCN). Knowledge on its ecology, which is crucial to design proper conservation and management plans, is very scarce. Here we describe the isolation of eight polymorphic microsatellite loci using 454 GS-FLX Titanium pyrosequencing of enriched DNA libraries. Their characteristics were tested on a population of tiger shark (n = 101) from Reunion Island (South-Western Indian Ocean). All loci were polymorphic with a number of alleles ranging from two to eight. No null alleles were detected and no linkage disequilibrium was detected after Bonferroni correction. Observed and expected heterozygosities ranged from 0.03 to 0.76 and from 0.03 to 0.77, respectively. No locus deviated from Hardy-Weinberg equilibrium and the global F IS of the population was of 0.04 (NS) . Some of the eight loci developed here successfully cross-amplified in the bull shark Carcharhinus leucas (one locus), the spinner shark Carcharhinus brevipinna (four loci), the sandbar shark Carcharhinus plumbeus (five loci) and the scalloped hammerhead shark Sphyrna lewini (two loci). We also designed primers to amplify and sequence a mitochondrial marker, the control region. We sequenced 862 bp and found a low genetic diversity, with four polymorphic sites, a haplotype diversity of 0.15 and a nucleotide diversity of 2 × 10(-4). PMID:27231661

  16. Small but tough: What can ecophysiology of croaking gourami Trichopsis vittatus (Cuvier 1831) tell us about invasiveness of non-native fishes in Florida?

    USGS Publications Warehouse

    Schofield, Pam; Schulte, Jessica

    2016-01-01

    Trichopsis vittata (Cuvier, 1831) is a small, freshwater gourami (Fam: Osphronemidae) native to southeast Asia. It was first detected in Florida in the 1970s and seems to have persisted for decades in a small area. In this study, we documented T. vittata’s ecophysiological tolerances (salinity and low-temperature) and qualitatively compared them to published values for other sympatric non-native species that have successfully invaded much of the Florida peninsula. Trichopsis vittata survived acute salinity shifts to 16 psu and was able to survive up to 20 psu when salinity was raised more slowly (5 psu per week). In a cold-tolerance experiment, temperature was lowered from 24 °C at 1 °C hr-1 until fish died. Mean temperature at death (i.e., lower lethal limit) was 7.2 °C. Trichopsis vittata seems as tolerant or more tolerant than many other sympatric non-native fishes for the variables we examined. However, T. vittata is the only species that has not dispersed since its introduction. Species other than T. vittata have broadly invaded ranges, many of which include the entire lower third of the Florida peninsula. It is possible that tolerance to environmental parameters serves as a filter for establishment, wherein candidate species must possess the ability to survive abiotic extremes as a first step. However, a species’ ability to expand its geographic range may ultimately rely on a secondary set of criteria including biotic interactions and life-history variables.

  17. Isolation and characterization of eight microsatellite loci from Galeocerdo cuvier (tiger shark) and cross-amplification in Carcharhinus leucas, Carcharhinus brevipinna, Carcharhinus plumbeus and Sphyrna lewini

    PubMed Central

    Jaquemet, Sébastien; Blaison, Antonin; Soria, Marc; Magalon, Hélène

    2016-01-01

    The tiger shark Galeocerdo cuvier (Carcharhinidae) is a large elasmobranch suspected to have, as other apex predators, a keystone function in marine ecosystems and is currently considered Near Threatened (Red list IUCN). Knowledge on its ecology, which is crucial to design proper conservation and management plans, is very scarce. Here we describe the isolation of eight polymorphic microsatellite loci using 454 GS-FLX Titanium pyrosequencing of enriched DNA libraries. Their characteristics were tested on a population of tiger shark (n = 101) from Reunion Island (South-Western Indian Ocean). All loci were polymorphic with a number of alleles ranging from two to eight. No null alleles were detected and no linkage disequilibrium was detected after Bonferroni correction. Observed and expected heterozygosities ranged from 0.03 to 0.76 and from 0.03 to 0.77, respectively. No locus deviated from Hardy-Weinberg equilibrium and the global FIS of the population was of 0.04NS. Some of the eight loci developed here successfully cross-amplified in the bull shark Carcharhinus leucas (one locus), the spinner shark Carcharhinus brevipinna (four loci), the sandbar shark Carcharhinus plumbeus (five loci) and the scalloped hammerhead shark Sphyrna lewini (two loci). We also designed primers to amplify and sequence a mitochondrial marker, the control region. We sequenced 862 bp and found a low genetic diversity, with four polymorphic sites, a haplotype diversity of 0.15 and a nucleotide diversity of 2 × 10−4. PMID:27231661

  18. Isolation and characterization of eight microsatellite loci from Galeocerdo cuvier (tiger shark) and cross-amplification in Carcharhinus leucas, Carcharhinus brevipinna, Carcharhinus plumbeus and Sphyrna lewini.

    PubMed

    Pirog, Agathe; Jaquemet, Sébastien; Blaison, Antonin; Soria, Marc; Magalon, Hélène

    2016-01-01

    The tiger shark Galeocerdo cuvier (Carcharhinidae) is a large elasmobranch suspected to have, as other apex predators, a keystone function in marine ecosystems and is currently considered Near Threatened (Red list IUCN). Knowledge on its ecology, which is crucial to design proper conservation and management plans, is very scarce. Here we describe the isolation of eight polymorphic microsatellite loci using 454 GS-FLX Titanium pyrosequencing of enriched DNA libraries. Their characteristics were tested on a population of tiger shark (n = 101) from Reunion Island (South-Western Indian Ocean). All loci were polymorphic with a number of alleles ranging from two to eight. No null alleles were detected and no linkage disequilibrium was detected after Bonferroni correction. Observed and expected heterozygosities ranged from 0.03 to 0.76 and from 0.03 to 0.77, respectively. No locus deviated from Hardy-Weinberg equilibrium and the global F IS of the population was of 0.04 (NS) . Some of the eight loci developed here successfully cross-amplified in the bull shark Carcharhinus leucas (one locus), the spinner shark Carcharhinus brevipinna (four loci), the sandbar shark Carcharhinus plumbeus (five loci) and the scalloped hammerhead shark Sphyrna lewini (two loci). We also designed primers to amplify and sequence a mitochondrial marker, the control region. We sequenced 862 bp and found a low genetic diversity, with four polymorphic sites, a haplotype diversity of 0.15 and a nucleotide diversity of 2 × 10(-4).

  19. Simulating the effect of high-intensity sound on cetaceans: modeling approach and a case study for Cuvier's beaked whale (Ziphius cavirostris).

    PubMed

    Krysl, P; Cranford, T W; Wiggins, S M; Hildebrand, J A

    2006-10-01

    A finite element model is formulated to study the steady-state vibration response of the anatomy of a whale (Cetacea) submerged in seawater. The anatomy was reconstructed from a combination of two-dimensional (2D) computed tomography (CT) scan images, identification of Hounsfield units with tissue types, and mapping of mechanical properties. A partial differential equation model describes the motion of the tissues within a Lagrangean framework. The computational model was applied to the study of the response of the tissues within the head of a neonate Cuvier's beaked whale Ziphius cavirostris. The characteristics of the sound stimulus was a continuous wave excitation at 3500 Hz and 180 dB re: 1 microPa received level, incident as a plane wave. We model the beaked whale tissues embedded within a volume of seawater. To account for the finite dimensions of the computational volume, we increased the damping for viscous shear stresses within the water volume, in an attempt to reduce the contribution of waves reflected from the boundaries of the computational box. The mechanical response of the tissues was simulated including: strain amplitude; dissipated power; and pressure. The tissues are not likely to suffer direct mechanical or thermal damage, within the range of parameters tested.

  20. Metal concentration in water, sediment and four fish species from Lake Titicaca reveals a large-scale environmental concern.

    PubMed

    Monroy, Mario; Maceda-Veiga, Alberto; de Sostoa, Adolfo

    2014-07-15

    Although intensive mining activity and urban sewage discharge are major sources of metal inputs to Lake Titicaca, the risk posed by metal pollution to wildlife and human populations has been poorly studied. In this study we compared the concentrations of Cu, Zn, Cd, Hg, Pb, Co, and Fe in water, sediment, and two tissues (liver and muscle) of four fish species (Odontesthes bonariensis, Orestias luteus, Orestias agassii, and Trichomycterus rivulatus) across important fishery areas in Lake Titicaca. The concentration of Pb in water at the discharge sites of the main rivers and of most elements, with the exception of Co and Fe, in all fish collected in this study exceeded the safety thresholds established by international legislation. The highest metal concentrations were observed in benthopelagic species, and liver tissue was identified as the main depository for all metals with the exception of mercury. The metal bioaccumulation pattern in fish was weakly related to the metal concentrations in the environment with the exception of Hg at the most polluted location, partly explained by the different metabolic role of essential and non-essential elements and the influence of other factors such as species' ecology and individual traits in the bioaccumulation of most metals. As metal pollution extended across the study area and high metal concentrations were detected in all four fish species, we urge the authorities to enforce legislation for water and fish consumption and to evaluate the effects of metal pollution on fish health. PMID:24784748

  1. Metal concentration in water, sediment and four fish species from Lake Titicaca reveals a large-scale environmental concern.

    PubMed

    Monroy, Mario; Maceda-Veiga, Alberto; de Sostoa, Adolfo

    2014-07-15

    Although intensive mining activity and urban sewage discharge are major sources of metal inputs to Lake Titicaca, the risk posed by metal pollution to wildlife and human populations has been poorly studied. In this study we compared the concentrations of Cu, Zn, Cd, Hg, Pb, Co, and Fe in water, sediment, and two tissues (liver and muscle) of four fish species (Odontesthes bonariensis, Orestias luteus, Orestias agassii, and Trichomycterus rivulatus) across important fishery areas in Lake Titicaca. The concentration of Pb in water at the discharge sites of the main rivers and of most elements, with the exception of Co and Fe, in all fish collected in this study exceeded the safety thresholds established by international legislation. The highest metal concentrations were observed in benthopelagic species, and liver tissue was identified as the main depository for all metals with the exception of mercury. The metal bioaccumulation pattern in fish was weakly related to the metal concentrations in the environment with the exception of Hg at the most polluted location, partly explained by the different metabolic role of essential and non-essential elements and the influence of other factors such as species' ecology and individual traits in the bioaccumulation of most metals. As metal pollution extended across the study area and high metal concentrations were detected in all four fish species, we urge the authorities to enforce legislation for water and fish consumption and to evaluate the effects of metal pollution on fish health.

  2. Parasite communities of the elongate tigerfish Hydrocynus forskahlii (Cuvier 1819) and redbelly tilapia Tilapia zillii (Gervais 1848) from Lake Turkana, Kenya: influence of host sex and size.

    PubMed

    Otachi, Elick O; Szostakowska, Beata; Jirsa, Franz; Fellner-Frank, Christine

    2014-03-01

    Fish is an important food source for an estimated 300,000 people inhabiting the shores of Lake Turkana, Kenya. Despite its large size (7560 km2) and importance, the lake remains one of the least studied in the Great Lakes Region of Africa. This study describes the parasite community of the elongate tigerfish Hydrocynus forskahlii (Cuvier, 1819) and the redbelly tilapia Tilapia zillii (Gervais, 1848). A total of 87 individuals (43 H. forskahlii and 44 T. zillii) were dissected and examined for parasites. Two taxa infected H. forskahlii, the dominant one being an anisakid nematode Contracaecum sp. (L3) (P = 83.7%, mean intensity (MI) = 46.0, abundance (A) = 38.5). Twelve parasite taxa were recovered from T. zillii, with metacestodes of the gryporhynchid cestode Amirthalingamia macracantha being dominant (P = 79.5, MI = 10.3, A = 8.2). This was the first report of a mixture of merocercoids and plerocercoids in the same host. Fish size was positively correlated with the major parasite infection levels, but, the prevalence of Contracaecum sp. in H. forskahlii was negatively correlated with size, probably reflecting ontogenetic shifts in habitats and diets with age. Fish sex was not a significant influencing factor, with the exception of Contracaecum sp. in H. forskahlii, where prevalence differed significantly between sexes (p<0.05), with the females having a higher prevalence than the males. We conclude that H. forskahlii had a poor parasitic community but that the infection levels with Contracaecum sp. were high. T. zillii had a rich parasite fauna, although, most parasites occurred at low intensities.

  3. Estimates of direct and indirect effects for early juvenile survival in captive populations maintained for conservation purposes: the case of Cuvier's gazelle

    PubMed Central

    Ibáñez, Belén; Cervantes, Isabel; Gutiérrez, Juan P; Goyache, Félix; Moreno, Eulalia

    2014-01-01

    Together with the avoidance of any negative impact of inbreeding, preservation of genetic variability for life-history traits that could undergo future selective pressure is a major issue in endangered species management programmes. However, most of these programmes ignore that, apart from the direct action of genes on such traits, parents, as contributors of offspring environment, can influence offspring performance through indirect parental effects (when parental genotype and phenotype exerts environmental influences on offspring phenotype independently of additive genetic effects). Using quantitative genetic models, we estimated the additive genetic variance for juvenile survival in a population of the endangered Cuvier's gazelle kept in captivity since 1975. The dataset analyzed included performance recording for 700 calves and a total pedigree of 740 individuals. Results indicated that in this population juvenile survival harbors significant additive genetic variance. The estimates of heritability obtained were in general moderate (0.115–0.457) and not affected by the inclusion of inbreeding in the models. Maternal genetic contribution to juvenile survival seems to be of major importance in this gazelle's population as well. Indirect genetic and indirect environmental effects assigned to mothers (i.e., maternal genetic and maternal permanent environmental effects) roughly explain a quarter of the total variance estimated for the trait analyzed. These findings have major evolutionary consequences for the species as show that offspring phenotypes can evolve strictly through changes in the environment provided by mothers. They are also relevant for the captive breeding programme of the species. To take into account, the contribution that mothers have on offspring phenotype through indirect genetic effects when designing pairing strategies might serve to identify those females with better ability to recruit, and, additionally, to predict reliable responses to

  4. The impact of a dam on the helminth fauna and health of a neotropical fish species Salminus brasiliensis (Cuvier 1816) from the upper Paraná River, Brazil.

    PubMed

    Karling, L C; Isaac, A; Affonso, I P; Takemoto, R M; Pavanelli, G C

    2013-06-01

    The aim of the present study was to detect changes in the structure of the helminth parasite infracommunities in Salminus brasiliensis (Cuvier 1816) from the floodplain of the upper Paraná River after construction of the Porto Primavera Hydroelectric Plant. A total of 126 fish in the period before the dam's construction and 56 specimens 10 years after this event were analysed. Three species of parasites were collected before the construction of the dam: Prosthenhystera obesa Diesing, 1850 (Digenea), Cladocystis intestinalis Vaz, 1932 (Digenea) and Monticellia coryphicephala Monticelli, 1892 (Cestoda), and one nematode species in the larval stage, whose identification was not possible. After dam construction, the following helminth parasites were found: C. intestinalis, M. coryphicephala, Octospiniferoides incognita, Contracaecum spp. larvae and Contracaecum sp. type 2 larvae Moravec, Kohn & Fernandes 1993. The diversity of helminth parasites measured by the Brillouin diversity index (HB) differed significantly between the pre- and post-dam periods (mean HB = 0.069 and HB = 0.2, respectively; P= 0.0479; Mann-Whitney U test). The parasite community of S. brasiliensis before the construction of the dam showed concentration of dominance (C) of P. obesa (C = 0.38), while there was no concentration of dominance of any species of parasite (C = 0.22) after the dam's construction. Before the Porto Primavera dam the relative condition factor of fish was 1.0; after the dam's construction it was 0.93 (P < 0.0001; Mann-Whitney U test). This study records the disappearance of the species P. obesa and suggests that there has been local extinction of this parasite. The results show that the anthropic influence on natural systems is interfering with the welfare and health of S. brasiliensis, reflected by its fauna of helminth parasites. PMID:22776324

  5. Validity of a blue stripe snapper, Lutjanus octolineatus (Cuvier 1828) and a related species, L. bengalensis (Bloch 1790) with a new species (Pisces; Lutjanidae) from the Arabian Sea.

    PubMed

    Iwatsuki, Yukio; Al-Mamry, Juma M; Heemstra, Phillip C

    2016-04-07

    Lutjanus octolineatus (Cuvier 1828), previously considered a junior synonym of Lutjanus bengalensis (Bloch 1790), is shown to be a valid species and lectotypes are designated. Both species are redescribed. The two species have overlapping distributions in the Indian Ocean, but are clearly separable by different dorsal-fin spine counts, blue-striped pattern on the body and the presence or absence of a subocular extension of cheek scales. Lutjanus octovittata (Valenciennes 1830), formerly assigned to synonymy of L. bengalensis, is considered a junior synonym of L. octolineatus based on examination of the holotype. Lutjanus sapphirolineatus n. sp., a species formerly misidentified as L. bengalensis, is described based on 10 specimens from Oman and Somalia. The new species differs from the three species above by a combination of different characters. Analysis of the mitochondrial cytochrome c oxidase subunit 1 (CO1, 603 bp) genetic marker, also strongly supports the validity of each species of the blue-striped snapper complex as distinct.

  6. Two new species of Ergasilus Nordmann, 1832 (Copepoda: Ergasilidae) and a redescription of Ergasilus salmini Thatcher & Brazil-Sato, 2008 from Salminus brasiliensis Cuvier and S. franciscanus Lima & Britsky (Teleostei: Characidae) in Brazil.

    PubMed

    Marques, Taísa Mendes; Boeger, Walter A; de Carvalho Brasil-Sato, Marília

    2015-01-01

    Three species of Ergasilus Nordmann, 1832 are reported from the gills of Salminus spp. in Brazil. Ergasilus salmini Thatcher & Brazil-Sato, 2008 from Salminus brasiliensis Cuvier is redescribed, based on examination of paratypes. The study revealed morphological differences from the original description, especially in the morphology of the cephalothorax and the ornamentation of antenna, antennule and legs. Ergasilus lacusauratus n. sp. described from S. brasiliensis in lake Lagoa Dourada (Paraná) differs from the only known species from this host group, E. salmini, in the shape and size of the cephalothorax and the general morphology of the egg-sacs. Ergasilus sinefalcatus n. sp. from S. franciscanus Lima & Britsky in River São Francisco (Minas Gerais) closely resembles E. pitalicus, E. coatiarus and E. leporinidis in the lack of a pectinate seta on the first exopodal segment, a feature common in species of Ergasilus in the Neotropics. Ergasilus sinefalcatus n. sp. differs from these species in the presence of a spiniform process on the coxae of legs 2, 3 and 4, an ornament never reported from freshwater species of Ergasilus in South America. PMID:25557749

  7. Two new species of Ergasilus Nordmann, 1832 (Copepoda: Ergasilidae) and a redescription of Ergasilus salmini Thatcher & Brazil-Sato, 2008 from Salminus brasiliensis Cuvier and S. franciscanus Lima & Britsky (Teleostei: Characidae) in Brazil.

    PubMed

    Marques, Taísa Mendes; Boeger, Walter A; de Carvalho Brasil-Sato, Marília

    2015-01-01

    Three species of Ergasilus Nordmann, 1832 are reported from the gills of Salminus spp. in Brazil. Ergasilus salmini Thatcher & Brazil-Sato, 2008 from Salminus brasiliensis Cuvier is redescribed, based on examination of paratypes. The study revealed morphological differences from the original description, especially in the morphology of the cephalothorax and the ornamentation of antenna, antennule and legs. Ergasilus lacusauratus n. sp. described from S. brasiliensis in lake Lagoa Dourada (Paraná) differs from the only known species from this host group, E. salmini, in the shape and size of the cephalothorax and the general morphology of the egg-sacs. Ergasilus sinefalcatus n. sp. from S. franciscanus Lima & Britsky in River São Francisco (Minas Gerais) closely resembles E. pitalicus, E. coatiarus and E. leporinidis in the lack of a pectinate seta on the first exopodal segment, a feature common in species of Ergasilus in the Neotropics. Ergasilus sinefalcatus n. sp. differs from these species in the presence of a spiniform process on the coxae of legs 2, 3 and 4, an ornament never reported from freshwater species of Ergasilus in South America.

  8. Validity of a blue stripe snapper, Lutjanus octolineatus (Cuvier 1828) and a related species, L. bengalensis (Bloch 1790) with a new species (Pisces; Lutjanidae) from the Arabian Sea.

    PubMed

    Iwatsuki, Yukio; Al-Mamry, Juma M; Heemstra, Phillip C

    2016-01-01

    Lutjanus octolineatus (Cuvier 1828), previously considered a junior synonym of Lutjanus bengalensis (Bloch 1790), is shown to be a valid species and lectotypes are designated. Both species are redescribed. The two species have overlapping distributions in the Indian Ocean, but are clearly separable by different dorsal-fin spine counts, blue-striped pattern on the body and the presence or absence of a subocular extension of cheek scales. Lutjanus octovittata (Valenciennes 1830), formerly assigned to synonymy of L. bengalensis, is considered a junior synonym of L. octolineatus based on examination of the holotype. Lutjanus sapphirolineatus n. sp., a species formerly misidentified as L. bengalensis, is described based on 10 specimens from Oman and Somalia. The new species differs from the three species above by a combination of different characters. Analysis of the mitochondrial cytochrome c oxidase subunit 1 (CO1, 603 bp) genetic marker, also strongly supports the validity of each species of the blue-striped snapper complex as distinct. PMID:27394598

  9. Morphological and molecular description of Tenuisentis niloticus (Meyer, 1932) (Acanthocephala: Tenuisentidae) from Heterotis niloticus (Cuvier) (Actinopterygii: Arapaimidae), in Burkina Faso, with emendation of the family diagnosis and notes on new features, cryptic genetic diversity and histopathology.

    PubMed

    Amin, Omar M; Evans, R Paul; Boungou, Magloire; Heckmann, Richard

    2016-02-01

    Specimens described as Rhadinorhynchus niloticus Meyer, 1932 (Rhadinorhynchidae) from two male specimens collected from Heterotis niloticus (Cuvier) in the Egyptian Nile were later redescribed in the genus Tenuisentis Van Cleave, 1936 (Tenuisentidae) based on 12 specimens collected from the same host species in the White Nile. That redescription basically distinguished the two genera based on five traits but did not actually provide a formal description. His account left out information about cerebral ganglion, lemnisci, some reproductive structures, eggs, proboscis hook dissymmetry and roots, size of trunk and a few other structures. We provide (i) the first complete description of this species enhanced by SEM, molecular, and histo-pathological studies; (ii) expand the existing descriptions; (iii) correct questionable accounts advanced by Van Cleave on the cement gland and the hypodermal giant nuclei; and (iv) add descriptions of new features such as the para-receptacle structure which we also report from Paratenuisentis Bullock & Samuel, 1975, the only other genus in Tenuisentidae Van Cleave, 1936. The subsequent description of a few more specimens from the same host collected in Mali was more informative yet incomplete and at variance with our specimens from Burkina Faso. Genetic divergence and phylogenetic analyses of mitochondrial (cytochrome oxidase c subunit I; COI) and nuclear (18S ribosomal RNA) gene relationships uncovered a cryptic species complex containing two lineages. Based on our studies, the family diagnosis is emended. The acanthocephalan causes damage to the host intestine as depicted in histopathological sections. The invading worm can extend from the mucosal layer to the muscularis externa of the host with subsequent tissue necrosis, villi compression, haemorrhaging and blood loss. PMID:26790681

  10. Morphological and molecular description of Tenuisentis niloticus (Meyer, 1932) (Acanthocephala: Tenuisentidae) from Heterotis niloticus (Cuvier) (Actinopterygii: Arapaimidae), in Burkina Faso, with emendation of the family diagnosis and notes on new features, cryptic genetic diversity and histopathology.

    PubMed

    Amin, Omar M; Evans, R Paul; Boungou, Magloire; Heckmann, Richard

    2016-02-01

    Specimens described as Rhadinorhynchus niloticus Meyer, 1932 (Rhadinorhynchidae) from two male specimens collected from Heterotis niloticus (Cuvier) in the Egyptian Nile were later redescribed in the genus Tenuisentis Van Cleave, 1936 (Tenuisentidae) based on 12 specimens collected from the same host species in the White Nile. That redescription basically distinguished the two genera based on five traits but did not actually provide a formal description. His account left out information about cerebral ganglion, lemnisci, some reproductive structures, eggs, proboscis hook dissymmetry and roots, size of trunk and a few other structures. We provide (i) the first complete description of this species enhanced by SEM, molecular, and histo-pathological studies; (ii) expand the existing descriptions; (iii) correct questionable accounts advanced by Van Cleave on the cement gland and the hypodermal giant nuclei; and (iv) add descriptions of new features such as the para-receptacle structure which we also report from Paratenuisentis Bullock & Samuel, 1975, the only other genus in Tenuisentidae Van Cleave, 1936. The subsequent description of a few more specimens from the same host collected in Mali was more informative yet incomplete and at variance with our specimens from Burkina Faso. Genetic divergence and phylogenetic analyses of mitochondrial (cytochrome oxidase c subunit I; COI) and nuclear (18S ribosomal RNA) gene relationships uncovered a cryptic species complex containing two lineages. Based on our studies, the family diagnosis is emended. The acanthocephalan causes damage to the host intestine as depicted in histopathological sections. The invading worm can extend from the mucosal layer to the muscularis externa of the host with subsequent tissue necrosis, villi compression, haemorrhaging and blood loss.

  11. Case 3058. Arctocephalus F. Cuvier, 1826 and Callorhinus Gray, 1859 (Mammalia, Pinnipedia): proposed conservation by the designation of Phoca pusilla Schreber, [1775] as the type species of Arctocephalus; and Otaria Peron, 1816 and Eumetopias Gill, 1866: proposed conservation by the designation of Phoca leonina Molina, 1782 as the type species of Otaria

    USGS Publications Warehouse

    Gardner, A.L.; Robbins, C.B.

    1999-01-01

    The purpose of this application is to conserve the accustomed understanding and usage of the fur seal name Arctocephalus F. Cuvier, 1826 by the designation of Phoca pusilia Schreber, [1775] as the type species, thus conserving also the name Callorhinus Gray, 1859. At present Phoca ursina Linnaeus, 1758 is the valid type species of both Arctocephalus and Callorhinus. The name Arctocephalus relates to a genus of some seven fur seals from the southern hemisphere, while Callorhinus is used for the single species C. ursinus (Linnaeus) from the northern hemisphere. It is also proposed that the universal understanding of the names Otaria Peron, 1816 and Eumetopias Gill, 1866 should be conserved for the southern and northern sea lions respectively by designating Phoca leonina Molina, 1782 (for which the valid specific name is P. byronia de Blainville, 1820) as the type species of Otaria. At present Phoca jubata Schreber, [1776] is the type species of Otaria and the name Otaria is a senior subjective synonym of Eumetopias. The four genera Arctocephalus, Callorhinus, Otaria and Eumetopias are all placed in the family OTARIIDAE Gray, 1825.

  12. Cadmium induced malformation in eyes of Ambassis commersoni Cuvier

    SciTech Connect

    Pragatheeswaran, V. ); Loganathan, B. ); Natarajan, R. ); Venugopalan, V.K. )

    1989-11-01

    Pathological manifestations in fishes from the polluted environment reflect the deleterious effects of environmental damage to higher animals in the food chain including man. Industrial and mining wastes containing cadmium ions induced several abnormalities and metabolic disorders in aquatic animals. Though cadmium is reported to be toxic to all tissues of animals, cadmium-induced malformations in eyes of fish have not yet been described. During these investigations on acute toxicity of cadmium on the estuarine fish Ambassis commersoni, the authors observed the manifestations of creamy white eyes and protrusion of eye balls, leading to death of the fish. This paper deals with the eye malformation in cadmium-treated estuarine fish, A. commersoni. Cadmium induced behavioral changes and alteration in the glycogen levels in muscle and liver are also described.

  13. Croaking gourami, Trichopsis vittata (Cuvier, 1831), in Florida, USA

    USGS Publications Warehouse

    Schofield, Pamela J.; Pecora, Darren J.

    2013-01-01

    The croaking gourami, Trichopsis vittata, is documented from wetland habitats in southern Florida. This species was previously recorded from the same area over 15 years ago, but was considered extirpated. The rediscovery of a reproducing population of this species highlights the dearth of information available regarding the dozens of non-native fishes in Florida, as well as the need for additional research and monitoring.

  14. The complete validated mitochondrial genome of the silver gemfish Rexea solandri (Cuvier, 1832) (Perciformes, Gempylidae).

    PubMed

    Bustamante, Carlos; Ovenden, Jennifer R

    2016-01-01

    The silver gemfish Rexea solandri is an important economic resource but Vulnerable to overfishing in Australian waters. The complete mitochondrial genome sequence is described from 1.6 million reads obtained via next generation sequencing. The total length of the mitogenome is 16,350 bp comprising 2 rRNA, 13 protein-coding genes, 22 tRNA and 2 non-coding regions. The mitogenome sequence was validated against sequences of PCR fragments and BLAST queries of Genbank. Gene order was equivalent to that found in marine fishes. PMID:24621221

  15. The complete validated mitochondrial genome of the silver gemfish Rexea solandri (Cuvier, 1832) (Perciformes, Gempylidae).

    PubMed

    Bustamante, Carlos; Ovenden, Jennifer R

    2016-01-01

    The silver gemfish Rexea solandri is an important economic resource but Vulnerable to overfishing in Australian waters. The complete mitochondrial genome sequence is described from 1.6 million reads obtained via next generation sequencing. The total length of the mitogenome is 16,350 bp comprising 2 rRNA, 13 protein-coding genes, 22 tRNA and 2 non-coding regions. The mitogenome sequence was validated against sequences of PCR fragments and BLAST queries of Genbank. Gene order was equivalent to that found in marine fishes.

  16. Breeding and rearing of the two striped cardinalfish, Apogon quadrifasciatus (Cuvier, 1828) in captive condition.

    PubMed

    Saravanan, Ravichandran; Vijayanand, Packyaraj; Vagelli, Alejandro Alex; Murugan, Arumugam; Shanker, Selvaraju; Rajagopal, Santhanam; Balasubramanian, Thangavel

    2013-03-01

    The present study describes captive breeding, reproductive behavior and larval/juvenile rearing of Apogon quadrifasciatus. Spawning occurred 25 days after stocking in the breeding tank. Clutch size varied from 2500 to 3100. The males incubated the eggs, the incubation period was approximately five days at a mean temperature of 29 °C. The average total length of the newly hatched larvae was 2.6mm with an average mouth gape of 160 μm. Two experiments were conducted to determine the most suitable food items for the larvae. In the first (planktonic phase, day 1-13) larvae fed with copepod nauplli showed the highest survival (33%). In the second experiment (settlement phase, 14-26 days, copepod, Artemia sp. and Cyclop-Eeze), also showed that copepods were the preferred feed by the post hatching larvae. After 26 days, post hatching larvae were fed a diet that followed a protocol designed in accordance to the mouth size. Culture was maintained up to six months, and juveniles attained a maximum total length of 46.3 mm and a weight of about 3500 mg. Captive breeding and rearing of A. quadrifasciatus can help in restoring the wild populations impacted by local trawling activities as well as to supply this species to the ornamental fish trade, in a sustainable way.

  17. Transcriptomic Characterization of Tambaqui (Colossoma macropomum, Cuvier, 1818) Exposed to Three Climate Change Scenarios.

    PubMed

    Prado-Lima, Marcos; Val, Adalberto Luis

    2016-01-01

    Climate change substantially affects biodiversity around the world, especially in the Amazon region, which is home to a significant portion of the world's biodiversity. Freshwater fishes are susceptible to increases in water temperature and variations in the concentrations of dissolved gases, especially oxygen and carbon dioxide. It is important to understand the mechanisms underlying the physiological and biochemical abilities of fishes to survive such environmental changes. In the present study, we applied RNA-Seq and de novo transcriptome sequencing to evaluate transcriptome alterations in tambaqui when exposed to five or fifteen days of the B1, A1B and A2 climate scenarios foreseen by the IPCC. The generated ESTs were assembled into 54,206 contigs. Gene ontology analysis and the STRING tool were then used to identify candidate protein domains, genes and gene families potentially responsible for the adaptation of tambaqui to climate changes. After sequencing eight RNA-Seq libraries, 32,512 genes were identified and mapped using the Danio rerio genome as a reference. In total, 236 and 209 genes were differentially expressed at five and fifteen days, respectively, including chaperones, energetic metabolism-related genes, translation initiation factors and ribosomal genes. Gene ontology enrichment analysis revealed that mitochondrion, protein binding, protein metabolic process, metabolic processes, gene expression, structural constituent of ribosome and translation were the most represented terms. In addition, 1,202 simple sequence repeats were detected, 88 of which qualified for primer design. These results show that cellular response to climate change in tambaqui is complex, involving many genes, and it may be controlled by different cues and transcription/translation regulation mechanisms. The data generated from this study provide a valuable resource for further studies on the molecular mechanisms involved in the adaptation of tambaqui and other closely related teleost species to climate change.

  18. Morphological and biometric comparison of the scales of the barbels (Barbus cuvier) of Spain.

    PubMed

    Miranda, R; Escala, M

    2000-09-01

    The scales of 386 specimens of the eight species of the genus Barbus present in Spain (B. bocagei, B. comiza, B. graellsii, B. guiraonis, B. haasi, B. meridionalis, B. microcephalus, and B. sclateri) were studied. Six scales were extracted from each specimen, measurements taken, and the number of radii noted. Indices were obtained from these data. Statistical analysis allowed two groups to be established: 1) B. meridionalis and B. haasi, living in the upper stretches of rivers and distributed in the north of Spain; and 2) the remaining species. Within both groups a latitudinal gradation in the elongation of the scales and in the proportion of radii of the lateral fields was observed.

  19. The first description of oarfish Regalecus glesne (Regalecus russellii Cuvier 1816) ageing structures

    USGS Publications Warehouse

    Midway, S.R.; Wagner, Tyler

    2016-01-01

    Despite being a large, conspicuous teleost with a worldwide tropical and temperate distribution, the giant oarfish Regalecus spp. remain very rare fish species in terms of scientific sampling. Subsequently, very little biological information is known about Regalecus spp. and almost nothing has been concluded in the field of age and growth (Roberts, 2012). No studies of otoliths or temporal (annual) markings on any hard structures have been reported, and to our knowledge otoliths have never been recovered from any specimens (Tyson Roberts, personal communication),although a few texts do provide illustrations of Regalecus sp. otoliths (Lin and Chang, 2012; Nolf, 2013). Further inferential difficulty comes from the fact that age and growth studies of any Lampridiforme species are rare. Lampris guttatus is perhaps the only Lampridiforme species for which any biological information has been reported(Francis et al., 2004), which stems from the species commercial value. In order to begin understanding any species (for later purposes of management, conservation, etc.), basic biological information is needed. In the present study, we examine not only the first Regalecus russellii otolith, but provide suggestions toward future work that should direct data collection that can be used to generate basic biological information for this species.

  20. Transcriptomic Characterization of Tambaqui (Colossoma macropomum, Cuvier, 1818) Exposed to Three Climate Change Scenarios

    PubMed Central

    Prado-Lima, Marcos; Val, Adalberto Luis

    2016-01-01

    Climate change substantially affects biodiversity around the world, especially in the Amazon region, which is home to a significant portion of the world’s biodiversity. Freshwater fishes are susceptible to increases in water temperature and variations in the concentrations of dissolved gases, especially oxygen and carbon dioxide. It is important to understand the mechanisms underlying the physiological and biochemical abilities of fishes to survive such environmental changes. In the present study, we applied RNA-Seq and de novo transcriptome sequencing to evaluate transcriptome alterations in tambaqui when exposed to five or fifteen days of the B1, A1B and A2 climate scenarios foreseen by the IPCC. The generated ESTs were assembled into 54,206 contigs. Gene ontology analysis and the STRING tool were then used to identify candidate protein domains, genes and gene families potentially responsible for the adaptation of tambaqui to climate changes. After sequencing eight RNA-Seq libraries, 32,512 genes were identified and mapped using the Danio rerio genome as a reference. In total, 236 and 209 genes were differentially expressed at five and fifteen days, respectively, including chaperones, energetic metabolism-related genes, translation initiation factors and ribosomal genes. Gene ontology enrichment analysis revealed that mitochondrion, protein binding, protein metabolic process, metabolic processes, gene expression, structural constituent of ribosome and translation were the most represented terms. In addition, 1,202 simple sequence repeats were detected, 88 of which qualified for primer design. These results show that cellular response to climate change in tambaqui is complex, involving many genes, and it may be controlled by different cues and transcription/translation regulation mechanisms. The data generated from this study provide a valuable resource for further studies on the molecular mechanisms involved in the adaptation of tambaqui and other closely related teleost species to climate change. PMID:27018790

  1. Spatial distribution of Rastrelliger kanagurta (Cuvier 1817) in the South China Sea Exclusive Economic Zone (EEZ)

    NASA Astrophysics Data System (ADS)

    Razib, N. A.; Mustapha, M. A.

    2013-11-01

    Rastrelliger kanagurta inhabits the South China Sea, where it is the most abundant commercial fish. Understanding distribution of this species is important. Objective of this study is to describe the relationship between spatial distribution of R. kanagurta and its local environmental factors. Chlorophyll-a distribution and sea surface temperature was obtained from Aqua MODIS satellite image. Fisheries data of 2007 to 2010 were obtained from the Southeast Asean Fisheries Department Center (SEAFDEC). These data were analyzed in relation to physical and environmental factors to establish the spatial-temporal distribution of the species. Catch per unit effort (CPUE) was calculated from the fisheries data and used as abundance index. Kernel Density maps of the abundance were created. The result showed that the abundance generated by Kernel Density analysis at 10.0 to 12.0 were associated with chlorophyll-a concentration of 0.4 ± 0.1 mg/m3 and sea surface temperature of 27.0 ± 1.0 °C at offshore of Pahang coast. The density maps showed that the increase of R. kanagurta abundance was occurred in October. The environmental factors in South China Sea played an important role on R. kanagurta's density patterns. This study indicated the capability of GIS and satellite image to indicate aggregation area of R. kanagurta.

  2. Nematode larvae infecting Priacanthus arenatus Cuvier, 1829 (Pisces: Teleostei) in Brazil.

    PubMed

    Kuraiem, Bianca P; Knoff, Marcelo; Felizardo, Nilza N; Gomes, Delir C; Clemente, Sérgio C São

    2016-05-31

    From July to December, 2013, thirty Priacanthus arenatus specimens commercialized in the cities of Niterói and Rio de Janeiro, State of Rio de Janeiro, were acquired. The fish were necropsied and filleted to investigate the presence of nematode larvae. Twenty fish (66.7%) out of the total were parasitized by nematode larvae. A total of 2024 larvae were collected; among them, 30 third-instar larvae of Anisakis sp. showed prevalence (P) = 20%, mean abundance (MA) = 1, and the mean intensity (MI) = 5, and infection sites (IS) = caecum, stomach, liver, and mesentery; and 1,994 third-instar larvae (1,757 encysted and 237 free) of Hysterothylacium deardorffoverstreetorum with P = 66.7%, MA = 66.5, and MI = 99.7, and IS = spleen, caecum, stomach, liver, mesentery, and abdominal muscle. This is the first study to report H. deardorffoverstreetorum and Anisakis sp. larvae parasitizing P. arenatus.

  3. Regional movements of the tiger shark, Galeocerdo cuvier, off Northeastern Brazil: inferences regarding shark attack hazard.

    PubMed

    Hazin, Fábio H V; Afonso, André S; De Castilho, Pedro C; Ferreira, Luciana C; Rocha, Bruno C L M

    2013-09-01

    An abnormally high shark attack rate verified off Recife could be related to migratory behavior of tiger sharks. This situation started after the construction of the Suape port to the south of Recife. A previous study suggested that attacking sharks could be following northward currents and that they were being attracted shoreward by approaching vessels. In this scenario, such northward movement pattern could imply a higher probability of sharks accessing the littoral area of Recife after leaving Suape. Pop-up satellite archival tags were deployed on five tiger sharks caught off Recife to assess their movement patterns off northeastern Brazil. All tags transmitted from northward latitudes after 7-74 days of freedom. The shorter, soak distance between deployment and pop-up locations ranged between 33-209 km and implied minimum average speeds of 0.02-0.98 km.h-1. Both pop-up locations and depth data suggest that tiger shark movements were conducted mostly over the continental shelf. The smaller sharks moved to deeper waters within 24 hours after releasing, but they assumed a shallower (< 50 m) vertical distribution for most of the monitoring period. While presenting the first data on tiger shark movements in the South Atlantic, this study also adds new information for the reasoning of the high shark attack rate verified in this region.

  4. Organogenesis in the budding process of the freshwater bryozoan Cristatella mucedo Cuvier, 1798 (Bryozoa, Phylactolaemata).

    PubMed

    Schwaha, Thomas; Handschuh, Stephan; Redl, Emanuel; Walzl, Manfred G

    2011-03-01

    The phylogenetic position of bryozoans has been disputed for decades, and molecular phylogenetic analyzes have not unequivocally clarified their position within the Bilateria. As probably the most basal bryozoans, Phylactolaemata is the most promising taxon for large-scale phylogenetic comparisons. These comparisons require extending the morphological and developmental data by investigating different phylactolaemate species to identify basal characters and resolve in-group phylogeny. Accordingly, we analyzed the bud development and the organogenesis of the freshwater bryozoan Cristatella mucedo, with special focus on the formation of the digestive tract and differentiation of the coelomic compartments. Most parts of the digestive tract are formed as an outpocketing at the future anal side growing towards the mouth area. The ganglion is formed by an invagination between the anlagen of the mouth and anus. The lophophoral arms develop as paired lateral protrusions into the lumen of the bud and are temporarily connected by a median, thin bridge. All coelomic compartments are confluent during their development and also in the adult. The epistome coelom develops by fusion of two peritoneal infolds between the gut loop and overgrows the ganglion medially. The coelomic ring canal on the oral side develops by two lateral ingrowths and supplies the oral tentacles. On the forked canal, supplying the innermost row of tentacles above the epistome, a bladder-shaped swelling, probably with excretory function, is present in some adults. It remains difficult to draw comparisons to other phyla because only few studies have dealt with budding of potentially related taxa in more detail. Nonetheless, our results show that comparative organogenesis can contribute to phylactolaemate systematics and, when more data are available, possibly to that of other bryozoan classes and bilaterian phyla.

  5. Nematode larvae infecting Priacanthus arenatus Cuvier, 1829 (Pisces: Teleostei) in Brazil.

    PubMed

    Kuraiem, Bianca P; Knoff, Marcelo; Felizardo, Nilza N; Gomes, Delir C; Clemente, Sérgio C São

    2016-05-31

    From July to December, 2013, thirty Priacanthus arenatus specimens commercialized in the cities of Niterói and Rio de Janeiro, State of Rio de Janeiro, were acquired. The fish were necropsied and filleted to investigate the presence of nematode larvae. Twenty fish (66.7%) out of the total were parasitized by nematode larvae. A total of 2024 larvae were collected; among them, 30 third-instar larvae of Anisakis sp. showed prevalence (P) = 20%, mean abundance (MA) = 1, and the mean intensity (MI) = 5, and infection sites (IS) = caecum, stomach, liver, and mesentery; and 1,994 third-instar larvae (1,757 encysted and 237 free) of Hysterothylacium deardorffoverstreetorum with P = 66.7%, MA = 66.5, and MI = 99.7, and IS = spleen, caecum, stomach, liver, mesentery, and abdominal muscle. This is the first study to report H. deardorffoverstreetorum and Anisakis sp. larvae parasitizing P. arenatus. PMID:27254444

  6. Diurnal observations on the behavioral ecology of Gymnothorax moringa (Cuvier) and Muraena miliaris (Kaup) on a Caribbean coral reef

    NASA Astrophysics Data System (ADS)

    Abrams, R. W.; Abrams, M. D.; Schein, M. W.

    1983-09-01

    Activities of muraenids, primarily Gymnothorax moringa and Muraena miliaris, were observed on a Caribbean coral reef with a view to further understanding their role in the reef ecosystem. Other muraenid species included in the total of 198 sightings were Echidna catenata, Enchelycore nigricans, and an unidentified brown moray. The five species were unequally distributed among three basic habitats (sand, coral head, reef rock) available on the reef. Nine particular holes accounted for 52.5% of the total sightings, although hundreds of other seemingly appropriate sites were available. The eels (except M. miliaris) were transient with respect to given holes and particular sections of the reef. While some G. moringa were sighted in the same holes for several consecutive days, M. miliaris individuals remained in the same coral heads throughout the 6-week study period. Muraenids observed in this study showed high tolerances for and were tolerated by other fishes (including other morays) and invertebrates on the reef. They appeared to be opportunistic, roving predators and were not strictly nocturnal. Distinct behavioral interactions and displays between muraenids and reef fish were observed.

  7. A new species of the genus Scolopsis Cuvier, 1830 (Perciformes: Nemipteridae) from southern India and Sri Lanka.

    PubMed

    Mishra, S S; Biswas, Sudeepta; Russell, Barry C; Satpathy, K K; Selvanayagam, M

    2013-01-01

    Scolopsis igcarensis, a new species of monocle bream (family Nemipteridae) from the coastal waters of southern India and Sri Lanka is described. The species is distinguished from other species of the genus Scolopsis by a combination of the following characters: scales on top of head reaching forward to between anterior nostril and snout tip; lower margin of eye below the line from snout tip to upper pectoral fin base; a bony ridge below eye; a white band from behind eye to level of end of dorsal fin base. PMID:24699607

  8. Comparative studies of bile salts. A new type of bile salt from Arapaima gigas (Cuvier) (family Osteoglossidae)

    PubMed Central

    Haslewood, G. A. D.; Tökés, L.

    1972-01-01

    1. Arapaima gigas bile salts were hydrolysed by alkali or cleaved with dioxan–trichloroacetic acid to give cholic acid, arapaimic acid, arapaimol-A and arapaimol-B. 2. I.r., n.m.r. and mass spectroscopy and [α]D measurements indicated that arapaimic acid and arapaimol-A and -B are respectively 2α,3α,7α,12α-tetrahydroxy-5β,25∈-cholestan-26-oic acid, 5β,25R-cholestane-2β,3α,7α,12α,26-pentol and 5β-cholestane-2β,3α,7α,12α,26,27-hexol. 3. Partial synthesis of 2β,3α,7α,12α-tetrahydroxy-5α- and -5β-cholan-24-oic acid and their spectral examination fully confirmed these conclusions. 4. A. gigas bile salts show primitive features in that they comprise alcohol sulphates and a C27 acid; they are also specialized in showing 2β-hydroxylation. PMID:5073728

  9. Fatal attack by a juvenile tiger shark, Galeocerdo cuvier, on a kitesurfer in New Caledonia (South Pacific).

    PubMed

    Clua, Eric; Bescond, Pierre-Marie; Reid, Dennis

    2014-07-01

    We present a case of a non-provoked fatal shark attack on a 15-year old male kitesurfer in New Caledonia. The victim lost his board and was pulled by the sail along the water surface in a reef passage when a shark attacked. The shark inflicted at least two bites on the left leg, including a severe one around the knee, resulting in a quick hypovolemic shock that was fatal. The analysis of one of these bites indicated that a 2.8 m TL (est. length) tiger shark was responsible for this attack. The features of the attack are consistent with those of a predator response to a surface feeding stimulus.

  10. Fatal tiger shark, Galeocerdo cuvier attack in New Caledonia erroneously ascribed to great white shark, Carcharodon carcharias.

    PubMed

    Tirard, Philippe; Maillaud, Claude; Borsa, Philippe

    2015-07-01

    To understand the causes and patterns of shark attacks on humans, accurate identification of the shark species involved is necessary. Often, the only reliable evidence for this comes from the characteristics of the wounds exhibited by the victim. The present case report is intended as a reappraisal of the Luengoni, 2007 case (International Shark Attack File no. 4299) where a single shark bite provoked the death of a swimmer by haemorrhagic shock. Our examination of the wounds on the body of the victim, here documented by so-far unpublished photographic evidence, determined that the shark possessed large and homodontous jaws. This demonstrates that the attacker was a tiger shark, not a great white shark as previously published. PMID:26048500

  11. Stocking density and Piscirickettsia salmonis infection effect on Patagonian blennie (Eleginops maclovinus, Cuvier 1830) skeletal muscle intermediate metabolism.

    PubMed

    Vargas-Chacoff, L; Ortíz, E; Oyarzún, R; Martínez, D; Saavedra, E; Sá, R; Olavarría, V; Nualart, D; Yáñez, A; Bertrán, C; Mancera, J M

    2014-12-01

    The need to expand aquaculture production has led to other fish to be considered as potential species for culture, such as the sub-Antarctic notothenioid Eleginops maclovinus (Valenciennes, 1830). The aim of this study was to determine the cumulative effect of density and pathogen infection by protein extract of Piscirickettsia salmonis on skeletal muscle metabolism. In a first experiment, specimens were submitted to three different stocking densities: (1) 3.1 kg m(-3), (2) 15 kg m(-3) and (3) 60 kg m(-3), for a period of 10 days. In a second experiment, metabolic changes caused by an infection of P. salmonis protein extract (a single injection of 0.5 μL P. salmonis protein extract g body weight(-1) was inoculated in the fish) and its combined effect with stocking density was assessed during a period of 10 days. This study concludes that stress caused by high stocking density led to the reorganization of some metabolic routes to fulfill skeletal muscle energy needs. Furthermore, infection response by pathogen P. salmonis differed when stocking density increased, suggesting an increase of energy needs with density in skeletal muscle of infected fish.

  12. Structural indexes and sexual maturity of tambaqui Colossoma macropomum (Cuvier, 1818) (Characiformes: Characidae) in central Amazon, Brazil.

    PubMed

    Villacorta-Correa, M A; Saint-Paul, U

    1999-11-01

    Length, weight, structural index and sexual maturity in tambaqui Colossoma macropomum were analysed. 449 specimens were obtained from the commercial fishing fleet arriving at Manaus Harbour from the floodplain areas from May 1992 to July 1993. The objective of this study is to describe changes in structural index during one hidrological cycle and to interpret them according to the water level fluctuations and to also determine the time, reproductive period and length in sexual maturity. Sex ratio in tambaqui was 1:1 however, the length of females was significantly longer than males'. Length/weight relationship was described by the expression: Pt = 0.00058*Cp2.9039. b value was significantly different from 3 which meant an alometric growth. Lower condition index values (Kn) were found from August to October at the end of receding water and dry period. The feeding index was significantly lower during the receding water and dry period. Lower hepatosomatic index values were found in December during the dry period. Fishes in lengths longer than 550 mm which were more common from September to December during the dry period, stored larger cavitary fat reserves. Fishes smaller than the standard length of 550 mm stored less fat reserves and were more common during the rising of the water and flooding period. Spawning period of tambaqui extends from September to February in a total spawning synchronized with "repiquetes" (native term used to name a sudden recending and rising of the water level). Length of tambaqui was 60.69 cm, at sexual maturity.

  13. Fatal tiger shark, Galeocerdo cuvier attack in New Caledonia erroneously ascribed to great white shark, Carcharodon carcharias.

    PubMed

    Tirard, Philippe; Maillaud, Claude; Borsa, Philippe

    2015-07-01

    To understand the causes and patterns of shark attacks on humans, accurate identification of the shark species involved is necessary. Often, the only reliable evidence for this comes from the characteristics of the wounds exhibited by the victim. The present case report is intended as a reappraisal of the Luengoni, 2007 case (International Shark Attack File no. 4299) where a single shark bite provoked the death of a swimmer by haemorrhagic shock. Our examination of the wounds on the body of the victim, here documented by so-far unpublished photographic evidence, determined that the shark possessed large and homodontous jaws. This demonstrates that the attacker was a tiger shark, not a great white shark as previously published.

  14. Historical and contemporary evidence of a mutton snapper ( Lutjanus analis Cuvier, 1828) spawning aggregation fishery in decline

    NASA Astrophysics Data System (ADS)

    Graham, R. T.; Carcamo, R.; Rhodes, K. L.; Roberts, C. M.; Requena, N.

    2008-06-01

    Scientific information on reef fish spawning aggregation fisheries is sparse in light of numerous regional declines and extirpations from overexploitation. Fisher interviews of the small-scale commercial mutton snapper ( Lutjanus analis) spawning aggregation fishery at Gladden Spit, Belize, suggests a historic decadal decline. The reported trend is supported by analysis of inter-seasonal catch and effort and yield (2000 2002) that reveals a 59% decline in catch per unit effort (CPUE) and a 22% decrease in mean landings per boat. Declining population-level trends are also supported by a significant decrease in inter-annual median lengths of mutton snappers (2000 2006). These findings demonstrate the need for additional life history information that includes length-associated age and details on growth to provide clearer support of the effects on, and responses by, populations following fishing. In view of the historical changes to mutton snapper CPUE and landings at Gladden Spit and the fishery-associated declines in fish spawning aggregations observed globally, a precautionary approach to spawning aggregation management is warranted that provides full protection from fishing to enhance population persistence. The findings also highlight the need for substantially greater enforcement and long-term fisheries monitoring under a comprehensive regional management strategy.

  15. Re-description and Reassignment of the Damselfish Abudefduf luridus (Cuvier, 1830) Using Both Traditional and Geometric Morphometric Approaches

    SciTech Connect

    Cooper, W. James; Albertson, R Craig; Jacob, Rick E.; Westneat, Mark W.

    2014-12-01

    Here we present a re-description of Abudefduf luridus and reassign it to the genus Similiparma. We supplement traditional diagnoses and descriptions of this species with quantitative anatomical data collected from a family-wide geometric morphometric analysis of head morphology (44 species representing all 30 damselfish genera) and data from cranial micro-CT scans of fishes in the genus Similiparma. The use of geometric morphometric analyses (and other methods of shape analysis) permits detailed comparisons between the morphology of specific taxa and the anatomical diversity that has arisen in an entire lineage. This provides a particularly useful supplement to traditional description methods and we recommend the use of such techniques by systematists. Similiparma and its close relatives constitute a branch of the damselfish phylogenetic tree that predominantly inhabits rocky reefs in the Atlantic and Eastern Pacific, as opposed to the more commonly studied damselfishes that constitute a large portion of the ichthyofauna on all coral-reef communities.

  16. Expression pattern of heat-shock cognate 70 gene of humphead snapper, Lutjanus sanguineus (Cuvier), infected by Vibrio harveyi.

    PubMed

    Zhang, X Z; Wu, Z H; Yang, S P; Pang, H Y; Jian, J C; Lu, Y S

    2011-10-01

    The heat-shock cognate 70 (HSC70) gene of humphead snapper, Lutjanus sanguineus, designated as ByHSC70, was cloned by rapid amplification of cDNA ends (RACE) with the primers designed from the known expressed sequence tag (EST) identified from the subtracted cDNA library of the head kidney of humphead snapper. The full-length cDNA of ByHSC70 is 2313 bp, containing a 5' terminal untranslated region (UTR) of 96 bp, a 3' terminal UTR of 267 bp, and an open reading frame (ORF) of 1950 bp encoding a polypeptide of 650 amino acids with a theoretical molecular weight of 71.21 kDa and an estimated isoelectric point (pI) of 5.08. ByHSC70 contained three classical HSP70 family signatures. BLAST analysis showed that the amino acid sequence of ByHSC70 had the highest similarity of 99% when compared with other HSC70s. Fluorescent real-time quantitative RT-PCR was used to examine the expression of ByHSC70 gene in eight kinds of tissues/organs of humphead snapper after challenge with Vibrio harveyi. There was a clear time-dependent expression pattern of ByHSC70 in head kidney, spleen and thymus after bacterial challenge, and the expression of mRNA reached a maximum level at 9, 6 and 24 h post-infection and then returned to control levels after 15, 24 and 36 h, respectively. Our results suggest that HSC70 is an important component in the immune system of humphead snapper, its their rapid transcriptional upregulation in response to V. harveyi infection might be important for survival of humphead snapper.

  17. Growth, Age Validation, Mortality, and other Population Characteristics of the Red Emperor Snapper, Lutjanus sebae (Cuvier, 1828), off the Kimberley Coast of North-Western Australia

    NASA Astrophysics Data System (ADS)

    Newman, S. J.; Dunk, I. J.

    2002-07-01

    Red emperor, Lutjanus sebae, were examined from commercial catches in the Northern Demersal Scalefish Fishery (NDSF) of north-western Australia from 1997 to 1999. Specimens ranged from 183 to 728 mm fork length (FL); males had a mean FL of 509 mm, and were significantly larger than females that had a mean FL of 451 mm. Ages were estimated from thin sections of sagittal otoliths. Marginal increment analysis of sagittal otoliths showed a single annual minimum during September and October and indicated that one annulus is formed each year. Male L. sebae (n=977; 211-728 mm FL) ranged from age 2 to 30 years and females (n=1384; 183-584 mm FL) ranged from age 1 to 34 years. Sagittal otolith weight and height were significantly correlated with age for each sex. There was significant differential growth between sexes. The relationship of observed fork length at age was described by the von Bertalanffy growth equation for males, Lt=627·8 {1-exp [-0·151 (t+0·595)]} and females, Lt=482·6 {1-exp [-0·271 (t-0·065)]}. The slow growth, long life span and large size and age at maturity of L. sebae indicate that this species has a low production potential and hence spatial area closures are vulnerable to over-exploitation. The instantaneous rate of natural mortality (M) ranged from 0·104 to 0·122. The optimum rate of fishing mortality was estimated to be 0·052-0·061. The instantaneous rate of total mortality (Z) estimated from catch at age data for fully recruited ages, was 0·374 in 1997/98 and 0·242 in 1998/99. Hence, the NDSF population of L. sebae is exploited above optimum levels. Given their low production potential, populations of L. sebae in north-western Australia and elsewhere in the Indo-Pacific region require prudent management. Furthermore, fishery managers need to consider as part of any harvest strategy for these fish to preserve significant levels of the spawning stock.

  18. Stress indices of Grass carp, Ceteopharyngodon idella, (Cuvier and Valenciennes, 1884) change in response to Monogenean parasites pollution, Gyrodactylus spp. and Dactylogyrus spp.

    PubMed

    Tekmedash, Fatemeh Shojaei; Hemmatzadeh, Mohtaram; Khara, Hossein

    2016-09-01

    The aim of this research was study of stress indices in response to Monogenean infection in Grass carp, Ceteopharyngodon idella. In this regard, some stress indices were measured in two adult groups of Grass carp including healthy and infected fish. According to our results, the values of cortisol and glucose and lactate were significantly higher in infected fishes than healthy individuals. Elevation of cortisol and glucose demonstrated the existence of stressful condition caused by parasitic infection and demands for energy for adaptation. In conclusion, our results showed that Monogenean infection by Gyrodactylus spp. and Dactylogyrus spp. affects health condition of Grass carp through alternation of stress components. PMID:27605835

  19. Identification of a Δ5-like fatty acyl desaturase from the cephalopod Octopus vulgaris (Cuvier 1797) involved in the biosynthesis of essential fatty acids.

    PubMed

    Monroig, Oscar; Navarro, Juan C; Dick, James R; Alemany, Frederic; Tocher, Douglas R

    2012-08-01

    Long-chain polyunsaturated fatty acids (LC-PUFA) have been identified as essential compounds for common octopus (Octopus vulgaris), but precise dietary requirements have not been determined due, in part, to the inherent difficulties of performing feeding trials on paralarvae. Our objective is to establish the essential fatty acid (EFA) requirements for paralarval stages of the common octopus through characterisation of the enzymes of endogenous LC-PUFA biosynthetic pathways. In this study, we isolated a cDNA with high homology to fatty acyl desaturases (Fad). Functional characterisation in recombinant yeast showed that the octopus Fad exhibited Δ5-desaturation activity towards saturated and polyunsaturated fatty acyl substrates. Thus, it efficiently converted the yeast's endogenous 16:0 and 18:0 to 16:1n-11 and 18:1n-13, respectively, and desaturated exogenously added PUFA substrates 20:4n-3 and 20:3n-6 to 20:5n-3 (EPA) and 20:4n-6 (ARA), respectively. Although the Δ5 Fad enables common octopus to produce EPA and ARA, the low availability of its adequate substrates 20:4n-3 and 20:3n-6, either in the diet or by limited endogenous synthesis from C(18) PUFA, might indicate that EPA and ARA are indeed EFA for this species. Interestingly, the octopus Δ5 Fad can also participate in the biosynthesis of non-methylene-interrupted FA, PUFA that are generally uncommon in vertebrates but have been found previously in marine invertebrates, including molluscs, and now also confirmed to be present in specific tissues of common octopus.

  20. Stress indices of Grass carp, Ceteopharyngodon idella, (Cuvier and Valenciennes, 1884) change in response to Monogenean parasites pollution, Gyrodactylus spp. and Dactylogyrus spp.

    PubMed

    Tekmedash, Fatemeh Shojaei; Hemmatzadeh, Mohtaram; Khara, Hossein

    2016-09-01

    The aim of this research was study of stress indices in response to Monogenean infection in Grass carp, Ceteopharyngodon idella. In this regard, some stress indices were measured in two adult groups of Grass carp including healthy and infected fish. According to our results, the values of cortisol and glucose and lactate were significantly higher in infected fishes than healthy individuals. Elevation of cortisol and glucose demonstrated the existence of stressful condition caused by parasitic infection and demands for energy for adaptation. In conclusion, our results showed that Monogenean infection by Gyrodactylus spp. and Dactylogyrus spp. affects health condition of Grass carp through alternation of stress components.

  1. Two new species of Eunice Cuvier, 1817 (Polychaeta, Eunicidae) from the coral reefs of Hainan Island with a key to 16 species of Eunice from China seas.

    PubMed

    Wu, Xuwen; Sun, Ruiping; Liu, Ruiyu; Xu, Kuidong

    2013-01-01

    A taxonomic study of Eunice species based on material deposited in the Marine Biological Museum of the Chinese Academy of Sciences (MBMCAS) including recently collected specimens from coastal regions of Hainan Island, yielded two new species: Eunice hainanensis n. sp. and E. carrerai n. sp. Both species were collected from dead coral rocks in the reefs of the coastal region of Hainan Island, northern South China Sea. Eunice hainanensis has translucent bidentate subacicular hooks and branchiae present over an extensive region of the body. Within the Eunice group possessing these characters, the new species highly resembles E. schizobranchia Claparède, 1870 in having a numerous chaetigers and a very late start of branchiae (348-570 chaetigers with branchiae from chaetigers 69-72 vs. 731 chaetigers with branchiae from chaetiger 67). However, the two species differ by the presence of the maxillary plate VI (MxVI) in the new species (vs. absent in the latter). Besides, E. hainanensis is much smaller (1.7-1.9 mm vs. 5 mm in maximal width). Eunice carrerai belongs to the Eunice group that has dark bidentate subacicular hooks and branchiae present over an extensive region of the body. It can be distinguished from similar congeners that have the branchiae starting from chaetigers 3-4 and prostomial appendages with moniliform articulations by a combination of characters such as the presence of MxVI, notopodial articulations limited to anterior chaetigers, peristomial cirri articulated and extending to anterior edge of first peristomial ring. A key to 16 species of Eunice identified from China seas in the material examined with notes on their distribution is provided. The major characters of these species are briefly summarized.

  2. 75 FR 64507 - Taking and Importing Marine Mammals; Military Training Activities Conducted Within the Gulf of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-19

    ..., up to 15 individual beaked whales (of any of the following species: Baird's beaked whale, Cuvier's beaked whale, Stejneger's beaked whale) over the course of the 5-year regulations. ] Description...

  3. A complex of species related to Paradiscogaster glebulae (Digenea: Faustulidae) in chaetodontid fishes (Teleostei: Perciformes) of the Great Barrier Reef.

    PubMed

    Diaz, Pablo E; Bray, Rodney A; Cutmore, Scott C; Ward, Selina; Cribb, Thomas H

    2015-10-01

    A total of 1523 individuals of 34 species of chaetodontids from the Great Barrier Reef were examined for faustulid trematodes. Specimens resembling Paradiscogaster glebulae Bray, Cribb & Barker, 1994 were found in nine chaetodontid species at three localities. These specimens are shown, on the basis of combined morphological and molecular analyses, to comprise a complex of morphologically similar and partly cryptic species. The complex may comprise as many as six distinct species of which three are resolved here. The true P. glebulae is identified in Chaetodon ornatissimus Cuvier, 1831, Chaetodon aureofasciatus Macleay, 1878, Chaetodon plebeius Cuvier, 1831, Chaetodon rainfordi McCulloch, 1923 and Chaetodon speculum Cuvier, 1831. Two new species are described, Paradiscogaster munozae n. sp. from Heniochus varius (Cuvier, 1829), Heniochus chrysostomus Cuvier, 1831 and Chaetodon citrinellus Cuvier, 1831 and Paradiscogaster melendezi n. sp. from Chaetodon kleinii Bloch, 1790. In terms of morphology the three species differ most clearly in the development of the appendages on the ventral sucker. The three species differ at 3-6consistent bp of ITS2 rDNA. The host-specificity of the three species differs strikingly. P. melendezi n. sp. infects just one fish species, P. glebulae infects species of only one clade of Chaetodon, and P. munozae n. sp. infects quite unrelated species. The basis of this unusual pattern of host-specificity requires further exploration. Two of the species recognised here, P. glebulae and P. munozae n. sp., showed apparent intra-individual variation in the ITS2 rDNA sequences as demonstrated by clear, replicated double peaks in the electropherograms.

  4. 78 FR 66681 - Draft 2013 Marine Mammal Stock Assessment Reports

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-06

    ..., blue whale (Central North Pacific, Eastern North Pacific), fin whale (Hawaii, CA/OR/WA), false killer...), northern fur seal, bearded seal, ringed seal, ribbon seal, Cook Inlet beluga whales, narwhal, killer whale... stocks), sperm whale, beaked whales (Baird's, Cuvier's, and Stejneger's), western and central stocks...

  5. 75 FR 54095 - Takes of Marine Mammals Incidental to Specified Activities; Low-Energy Marine Seismic Survey in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ...: Bryde's whale; blue whale; sperm whale; humpback whale; Cuvier's beaked whale; Blainville's beaked whale...), and blue (Balaenoptera musculus) whales. Nine cetacean species, although present in the wider ETP....53 1.15 (Balaenoptera edeni). coastal. Blue whale, (Balaenoptera Uncommon....... Pelagic and 1415...

  6. 75 FR 43150 - Marine Mammals; File Nos. 10018, 13846, 14451, 14585, 14599, 14122, 14296, and 14353

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... endangered blue whales (Balaenoptera musculus), fin whales (B. physalus), humpback whales, sei whales (B... Pacific right whale (Eubalaena japonica), fin whale, blue whale, Cuvier's beaked whale (Ziphius... playbacks; (4) to gray, minke, fin, sei, blue, and North Pacific right whales for biological sampling......

  7. 76 FR 542 - Marine Mammals; File No. 15616

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-05

    ... of killer whale predation. The applicant requests to photoidentify and acoustically record (PI... cetacean species: killer whales (PI 2000, BS 100, DT 75, ST 75), gray whales (Eschrichtius robustus; PI 100, BS 8, DT 25), Baird's beaked whales (Berardius bairdii; PI 50, BS 8, DT 8), Cuvier's beaked...

  8. Passive acoustic monitoring of beaked whale densities in the Gulf of Mexico.

    PubMed

    Hildebrand, John A; Baumann-Pickering, Simone; Frasier, Kaitlin E; Trickey, Jennifer S; Merkens, Karlina P; Wiggins, Sean M; McDonald, Mark A; Garrison, Lance P; Harris, Danielle; Marques, Tiago A; Thomas, Len

    2015-11-12

    Beaked whales are deep diving elusive animals, difficult to census with conventional visual surveys. Methods are presented for the density estimation of beaked whales, using passive acoustic monitoring data collected at sites in the Gulf of Mexico (GOM) from the period during and following the Deepwater Horizon oil spill (2010-2013). Beaked whale species detected include: Gervais' (Mesoplodon europaeus), Cuvier's (Ziphius cavirostris), Blainville's (Mesoplodon densirostris) and an unknown species of Mesoplodon sp. (designated as Beaked Whale Gulf - BWG). For Gervais' and Cuvier's beaked whales, we estimated weekly animal density using two methods, one based on the number of echolocation clicks, and another based on the detection of animal groups during 5 min time-bins. Density estimates derived from these two methods were in good general agreement. At two sites in the western GOM, Gervais' beaked whales were present throughout the monitoring period, but Cuvier's beaked whales were present only seasonally, with periods of low density during the summer and higher density in the winter. At an eastern GOM site, both Gervais' and Cuvier's beaked whales had a high density throughout the monitoring period.

  9. 75 FR 44986 - Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-30

    ... investigators and to allow additional sampling for hair from polar bears (Ursus maritimus) for the purpose of...; PRT-17384A The applicant requests a permit to import 10 live captive-born Mhorr gazelles (Nanger dama mhorr) and three live captive-born Cuvier's gazelles (Gazella cuvieri) from Mountain View...

  10. Interoceanic occurrence of species of Aristocleidus Mueller, 1936 (Monogenoidea: Dactylogyridae) parasitizing the gills of gerreid fishes in the Neotropics.

    PubMed

    Mendoza Franco, Edgar F; Violante-González, Juan; Roche, Dominique G

    2009-09-01

    During investigations of fish parasites in the Neotropics (including the state of Veracruz and the Yucatán Peninsula in the Gulf of Mexico, the Chautengo Lagoon on the Pacific coast of the state of Guerrero in Mexico, and Lake Gatun in the Panama Canal), three monogenoidean (Dactylogyridae) species were found parasitizing the gills of gerreids (Gerreidae): Aristocleidus hastatus Mueller, 1936, was recovered from Eugerres plumieri (Cuvier) and Diapterus auratus Ranzani in Veracruz, from D. auratus and Diapterus rhombeus (Cuvier) in Yucatán, from Eugerres brasilianus (Cuvier) in Panama (all new hosts and geographical records), and from D. peruvianus (Cuvier) and Gerres cinereus (Walbaum) in Guerrero; Aristocleidus lamothei Kritsky and Mendoza-Franco, 2008, was recovered from E. plumieri in Veracruz and from D. rhombeus in Yucatan (new hosts and geographical records), and Aristocleidus sp. was recovered from G. cinereus in Guerrero. Results from this study suggest that species of Aristocleidus exhibit wide host specificity within gerreid fishes and that geminate species within this parasite genus may have originated with the formation of the Isthmus of Panama (3.1 to 3.5 ma). Evidence is also presented suggesting the potential role of the Panama Canal as a passageway allowing the interoceanic dispersal of Aristocleidus species across the isthmus. PMID:19415330

  11. Phanurus oligoovus gen. et sp. nov. (Digenea: Waretrematidae) from Liza carinatus from the South China Sea.

    PubMed

    Liu, Sheng-fa; Yang, Ting-bao

    2002-04-01

    The species Phanurus oligoovus gen. et sp. nov. is described from the intestine of Liza carinatus (Cuvier et Valencienne) from the South China Sea. From the general internal anatomy, it belongs to the Waretrematidae and is distinguished from the other known species of the Waretrematidae by the tail appendage. A new subfamily, Phanurunae, is proposed for the genus Phanurus.

  12. Feeding ecology and trophic comparisons of six shark species in a coastal ecosystem off southern Brazil.

    PubMed

    Bornatowski, H; Braga, R R; Abilhoa, V; Corrêa, M F M

    2014-08-01

    The diets of six shark species, Sphyrna lewini, Sphyrna zygaena, Carcharhinus obscurus, Carcharhinus limbatus, Rhizoprionodon lalandii and Galeocerdo cuvier, were investigated in a subtropical coastal ecosystem of southern Brazil. Stomach content data were obtained to assess foraging niche segregation and ontogenetic shifts in the diets of these sharks. Five of the shark species off the Paraná coast were ichthyophagous, with the exception of S. zygaena, which was teutophagous. With the exception of G. cuvier, which had a generalist diet, the other five species displayed specialization in their feeding. Ontogenetic shifts were observed in C. obscurus and S. lewini with large individuals consuming elasmobranchs. Owing to the diet overlap between C. obscurus and S. lewini, C. obscurus and C. limbatus and R. lalandii and C. limbatus, future studies on the spatial and temporal distributions of these species are needed to understand the extent of competitive interactions.

  13. Feeding ecology and trophic comparisons of six shark species in a coastal ecosystem off southern Brazil.

    PubMed

    Bornatowski, H; Braga, R R; Abilhoa, V; Corrêa, M F M

    2014-08-01

    The diets of six shark species, Sphyrna lewini, Sphyrna zygaena, Carcharhinus obscurus, Carcharhinus limbatus, Rhizoprionodon lalandii and Galeocerdo cuvier, were investigated in a subtropical coastal ecosystem of southern Brazil. Stomach content data were obtained to assess foraging niche segregation and ontogenetic shifts in the diets of these sharks. Five of the shark species off the Paraná coast were ichthyophagous, with the exception of S. zygaena, which was teutophagous. With the exception of G. cuvier, which had a generalist diet, the other five species displayed specialization in their feeding. Ontogenetic shifts were observed in C. obscurus and S. lewini with large individuals consuming elasmobranchs. Owing to the diet overlap between C. obscurus and S. lewini, C. obscurus and C. limbatus and R. lalandii and C. limbatus, future studies on the spatial and temporal distributions of these species are needed to understand the extent of competitive interactions. PMID:24919949

  14. A new metric for measuring condition in large predatory sharks.

    PubMed

    Irschick, D J; Hammerschlag, N

    2014-09-01

    A simple metric (span condition analysis; SCA) is presented for quantifying the condition of sharks based on four measurements of body girth relative to body length. Data on 104 live sharks from four species that vary in body form, behaviour and habitat use (Carcharhinus leucas, Carcharhinus limbatus, Ginglymostoma cirratum and Galeocerdo cuvier) are given. Condition shows similar levels of variability among individuals within each species. Carcharhinus leucas showed a positive relationship between condition and body size, whereas the other three species showed no relationship. There was little evidence for strong differences in condition between males and females, although more male sharks are needed for some species (e.g. G. cuvier) to verify this finding. SCA is potentially viable for other large marine or terrestrial animals that are captured live and then released. PMID:25130454

  15. A new species of Mymarothecium and new host and geographical records for M. viatorum (Monogenea: Dactylogyridae), parasites of freshwater fishes in Brazil.

    PubMed

    Cohen, Simone Chinicz; Kohn, Anna

    2005-11-01

    Mymarothecium boegeri sp. n. (Monogenea: Dactylogyridae) is described from the gills of Colossoma macropomum Cuvier (Characidae), collected from the aquaria of the "Centro de Pesquisas em Aquicultura, Departamento Nacional de Obras Contra as Secas (DNOCS)", Pentecoste City, State of Ceará, Brazil. Mymarothecium viatorum Boeger, Piasecki et Sobecka, 2002 is reported from the type host, Piaractus brachypomus (Cuvier) (Characidae) and from a new host, P. mesopotamicus (Holmberg) (Characidae), confirming the occurrence of M. viatorum in the Neotropical Region. The new species differs from the congeneric species in the structure of male copulatory complex; it is more closely related to M. viatorum by the presence of a posteromedial projection on ventral bar. PMID:16405294

  16. Risk mapping for sensitive species to underwater anthropogenic sound emissions: model development and validation in two Mediterranean areas.

    PubMed

    Azzellino, A; Lanfredi, C; D'Amico, A; Pavan, G; Podestà, M; Haun, J

    2011-01-01

    Recent observations of cetacean mass strandings, coincident with anthropogenic sounds emissions, have raised concerns on the potential environmental impact of underwater noise. Cuvier's beaked whale (Ziphius cavirostris) was reported in all the cited stranding events. Within the NATO Marine Mammal Risk Mitigation project (MMRM), multiple interdisciplinary sea trials have been conducted in the Mediterranean Sea with the objective of developing tools and procedures to mitigate the impact of underwater sound emissions. During these cruises, visual observations, passive acoustic detections and environmental data were collected. The aim of this study was to evaluate "a priori" predictions of Cuvier's beaked whale presence in the Alboran Sea, using models developed in the Ligurian Sea that employ bathymetric and chlorophyll features as predictors. The accuracy of these predictions was found adequate and elements are given to account for the uncertainties associated to the use of models developed in areas different from their calibration site. PMID:21349554

  17. Risk mapping for sensitive species to underwater anthropogenic sound emissions: model development and validation in two Mediterranean areas.

    PubMed

    Azzellino, A; Lanfredi, C; D'Amico, A; Pavan, G; Podestà, M; Haun, J

    2011-01-01

    Recent observations of cetacean mass strandings, coincident with anthropogenic sounds emissions, have raised concerns on the potential environmental impact of underwater noise. Cuvier's beaked whale (Ziphius cavirostris) was reported in all the cited stranding events. Within the NATO Marine Mammal Risk Mitigation project (MMRM), multiple interdisciplinary sea trials have been conducted in the Mediterranean Sea with the objective of developing tools and procedures to mitigate the impact of underwater sound emissions. During these cruises, visual observations, passive acoustic detections and environmental data were collected. The aim of this study was to evaluate "a priori" predictions of Cuvier's beaked whale presence in the Alboran Sea, using models developed in the Ligurian Sea that employ bathymetric and chlorophyll features as predictors. The accuracy of these predictions was found adequate and elements are given to account for the uncertainties associated to the use of models developed in areas different from their calibration site.

  18. Review of the harvestfishes, genus Peprilus (Perciformes: Stromateidae),
    of the Atlantic coast of South America.

    PubMed

    Marceniuk, Alexandre P; Caires, Rodrigo; Siccha-Ramirez, Raquel; Oliveira, Claudio

    2016-01-01

    Currently, seven valid species are recognized in the genus Peprilus. Found from United States to Argentina, Peprilus paru has a complex nomenclatural history, with seven junior synonyms, three from North America and four from South America. As there has been no recent research, it remains unclear whether species representatives in the north-south axis represent different populations of a single species or distinct species. By comparison of type specimens as well as a comprehensive collection of non-type specimens, this paper aims to clarify the taxonomic status of the nominal species listed as junior synonyms of Peprilus paru in the Atlantic side of South America. Based on morphological data and DNA barcoding, Peprilus crenulatus Cuvier, 1829 and P. xanthurus (Quoy & Gaimard, 1825) are resurrected, while Rhombus argentipinnis Cuvier, 1833 and Rhombus orbicularis Guichenot, 1866, are considered to be junior synonyms of P. crenulatus. PMID:27394588

  19. Herpesvirus infection with severe lymphoid necrosis affecting a beaked whale stranded in the Canary Islands.

    PubMed

    Arbelo, Manuel; Sierra, Eva; Esperón, Fernando; Watanabe, Tatiane T N; Bellière, Edwige N; Espinosa de los Monteros, Antonio; Fernández, Antonio

    2010-04-01

    This report describes the pathologic findings in a single, adult female Cuvier's beaked whale Ziphius cavirostris stranded in the Canary Islands. The study indicated that this whale died with a severe, systemic, herpesviral infection and clearly exhibited lesions different from those of the fat and gas embolic syndrome described in beaked whale mass strandings associated with sonar exposure. This is the first report of a cetacean alphaherpesvirus infection of the lymphoid system in a beaked whale.

  20. Adrenocortical and adrenomedullary homologs in eight species of adult and developing teleosts: morphology, histology, and immunohistochemistry.

    PubMed

    Grassi Milano, E; Basari, F; Chimenti, C

    1997-12-01

    Morphology, histology, and immunohistochemistry of the adrenocortical and adrenomedullary homologs (adrenal glands) of the following developing and adult teleosts were examined: Salmoniformes-Oncorhynchus mykiss (rainbow trout), Salmo trutta fario (brown trout), Coregonus lavaretus (white fish); Cyprinodontiformes-Gambusia affinis (mosquito fish). Perciformes-Dicentrarchus labrax (sea bass), Sparus aurata (sea bream), Diplodus sargus (white bream), Oblada melanura (saddled bream). The anatomical relationships of the gland with the renal system and venous vessels were also noted. In adults of all species steroidogenic and catecholaminergic chromaffin cells were found in the head kidney, which is pronephric in origin and subsequently transformed into a hematopoietic lymphatic organ. In Perciformes, chromaffin cells are distributed around the anterior and posterior cardinal veins and ducts of Cuvier; in Salmoniformes, around the posterior cardinal veins and in the hematopoietic tissue; and in G. affinis, around the ducts of Cuvier and posterior cardinal veins, while a few are visible also around the sinus venosus. In Perciformes and Salmoniformes, numerous chromaffin cells are also present in the posterior kidney, derived from the opisthonephros, in contact with the caudal vein. Steroidogenic cells are always confined to the head kidney. During development chromaffin and steroidogenic cells appear early after hatching in the pronephric kidney, at the level of the ducts of Cuvier and of the cephalic part of the posterior cardinal veins. Later, chromaffin cells in Perciformes reach the anterior cardinal veins, and subsequently, in both Perciformes and Salmoniformes, they reach the developing posterior kidney. Their localization along the posterior kidney is still in progress about 4 months after hatching and is completed about a year after hatching. These findings support the concept that the structure of the adrenal gland in teleosts is intermediate between that of the

  1. New geographic records of Hamlets, Hypoplectrus spp. (Serranidae), in the Caribbean Sea

    USGS Publications Warehouse

    Williams, E.H.; Bunkley-Williams, L.; Rogers, C.S.; Fenner, R.

    2006-01-01

    The exact number of species of hamlets, Hypoplectrus spp., in the Caribbean is controversial and the geographic distributions of these species/forms are poorly documented. We report Curac??ao, Netherlands Antilles, as a new locality for the Barred Hamlet, H. puella (Cuvier), and Shy Hamlet, H. guttavarius (Poey); and St. John and St. Thomas, U.S. Virgin Islands, for the Tan Hamlet, Hypoplectrus sp. The Black Hamlet, H. nigricans (Poey), has previously been reported from Curac??ao, but we did not see it there.

  2. Output of gastrointestinal nematode eggs in the feces of captive gazelles (Gazella dama mhorr, Gazella cuvieri and Gazella dorcas neglecta) in a semiarid region of southeastern Spain.

    PubMed

    Ortiz, Juana; Ruiz de Ybáñez, Rocío; Abaigar, Teresa; Goyena, Marina; Garijo, Magdalena; Espeso, Gerardo; Cano, Mar

    2006-09-01

    Feces from 62 captive African gazelles, including Mhorr gazelles (Gazella dama mhorr), Cuvier's gazelles (Gazella cuvieri), and Dorcas gazelles (Gazella dorcas neglecta), were examined over the course of a year to quantitate nematode egg excretion patterns. Strongyloides sp. eggs appeared only in G. dama during the rainy season. Trichostrongylidae egg excretion showed a marked seasonal variation, with very low levels during the dry and hot period, a finding that is probably attributable to hypobiosis of the predominant species (Camelostrongylus mentulatus). Eggs of the Nematodirus sp., predominantly Nematodirus spathiger, were excreted throughout the year. No seasonal pattern was observed in Trichuris sp. egg excretion. PMID:17319122

  3. Effects of duty-cycled passive acoustic recordings on detecting the presence of beaked whales in the northwest Atlantic.

    PubMed

    Stanistreet, Joy E; Nowacek, Douglas P; Read, Andrew J; Baumann-Pickering, Simone; Moors-Murphy, Hilary B; Van Parijs, Sofie M

    2016-07-01

    This study investigated the effects of using duty-cycled passive acoustic recordings to monitor the daily presence of beaked whale species at three locations in the northwest Atlantic. Continuous acoustic records were subsampled to simulate duty cycles of 50%, 25%, and 10% and cycle period durations from 10 to 60 min. Short, frequent listening periods were most effective for assessing the daily presence of beaked whales. Furthermore, subsampling at low duty cycles led to consistently greater underestimation of Mesoplodon species than either Cuvier's beaked whales or northern bottlenose whales, leading to a potential bias in estimation of relative species occurrence. PMID:27475208

  4. Mercury concentrations of fish, river water, and sediment in the Río Ramis-Lake Titicaca watershed, Peru.

    PubMed

    Gammons, Christopher H; Slotton, Darell G; Gerbrandt, Butch; Weight, Willis; Young, Courtney A; McNearny, Richard L; Cámac, Eugenio; Calderón, Ruben; Tapia, Henri

    2006-09-15

    This study reports the first set of data on the concentration of mercury in muscle tissue of several varieties of fish from Lake Titicaca, including the pejerrey (Basilichthyes bonariensis), the carachi (Orestias), and 2 types of indigenous catfish (Trichomycterus). Approximately 27% of the pejerrey and 75% of the carachi exceeded the US EPA fish tissue-based water quality criterion level of 0.30 microg g(-1). Mercury levels of pejerrey increased with fish size, although this relationship was less apparent for the smaller carachi. The pejerrey and carachi are important food fish for local residents. A synoptic sampling of the Río Ramis--the largest tributary to Lake Titicaca--was conducted in an attempt to determine if mercury releases from artisanal gold mining could be an important source of Hg contamination to Lake Titicaca. Although highly elevated concentrations of Hg and other heavy metals were documented in headwater streams near the mining centers of La Rinconada and Cecilia, the quantity of Hg entering Lake Titicaca that could be attributed to mining in the Ramis watershed was below the quantifiable limit in our July 2002 study. This does not diminish the localized threat to mercury exposure for the artisanal gold miners themselves, as well as their families. Further studies of mercury dynamics in Lake Titicaca are recommended, as well as in the rivers draining into the lake. It is probable that most of the downgradient transport of Hg and other trace metals from the headwater mining centers occurs as suspended sediment during seasonal periods of high-flow. PMID:16271381

  5. First records of parasitic copepods (Crustacea, Siphonostomatoida) from marine fishes in Korea.

    PubMed

    Venmathi Maran, B A; Soh, H Y; Hwang, U W; Chang, C Y; Myoung, J G

    2015-06-01

    The knowledge of the biodiversity of parasitic copepods in South Korea is increasing. Interestingly we report here, some parasitic copepods considered as the first record of findings from Korea. Nine species of parasitic copepods (Siphonostomatoida) including six genera of three different families [Caligidae (7), Lernaeopodidae (1), Lernanthropidae (1)] were recovered from eight species of wild fishes in Korea: 1) Caligus hoplognathi Yamaguti & Yamasu, 1959 (♀, ♂) from the body surface of barred knifejaw Oplegnathus fasciatus (Temminck & Schlegel); 2) Caligus lagocephali Pillai, 1961 (♀) from the gills of panther puffer Takifugu pardalis (Temminck & Schlegel); 3) Euryphorus brachypterus (Gerstaecker, 1853) (♀, ♂) from the opercular cavity of Atlantic bluefin tuna Thunnus thynnus (Linnaeus); 4) Euryphorus nordmanni Milne Edwards, 1840 (♀, ♂) from the opercular cavity of common dolphin fish Coryphaena hippurus Linnaeus; 5) Gloiopotes huttoni (Thomson) (♀, ♂) from the body surface of black marlin Istiompax indica (Cuvier); 6) Lepeophtheirus hapalogenyos Yamaguti & Yamasu, 1959 (♀) from the gill filaments of O. fasciatus; 7) Lepeophtheirus sekii Yamaguti, 1936 (♀, ♂) from the body surface of red seabream Pagrus major (Temminck & Schlegel); 8) Brachiella thynni Cuvier, 1830 (♀) from the body surface of longfin tuna or albacore Thunnus alalunga (Bonnaterre); 9) Lernanthropinus sphyraenae (Yamaguti & Yamasu, 1959) (♀) from the gill filaments of moon fish Mene maculata (Bloch & Schneider). Since the female was already reported in Korea, it is a new record for the male of C. hoplognathi. A checklist for the parasitic copepods of the family Caligidae, Lernaeopodidae and Lernanthropidae of Korea is provided.

  6. Hirudinella ventricosa (Pallas, 1774) Baird, 1853 represents a species complex based on ribosomal DNA.

    PubMed

    Calhoun, Dana M; Curran, Stephen S; Pulis, Eric E; Provaznik, Jennifer M; Franks, James S

    2013-10-01

    Digeneans in the genus Hirudinella de Blainville, 1828 (Hirudinellidae) from three species of pelagic fishes, Acanthocybium solandri (Cuvier), Makaira nigricans Lacépède and Thunnus albacares (Bonnaterre), and one benthic fish, Mulloidichthys martinicus (Cuvier), from the Gulf of Mexico are investigated using comparison of ribosomal DNA. Four species are identified based on molecular differences: Hirudinella ventricosa (Pallas, 1774) Baird, 1853 from A. solandri, Hirudinella ahi Yamaguti, 1970 from T. albacares, and two unidentified but distinct species of Hirudinella, herein referred to as Hirudinella sp. A (from both M. nigricans and M. martinicus) and Hirudinella sp. B from M. nigricans. Additionally, H. ahi, based tentatively on morphological identification, is reported from Thunnus thynnus (Linnaeus). This represents the first record of a hirudinellid from M. martinicus and the first record of H. ahi from T. thynnus. A phylogeny of some Hemiurata Skrjabin & Guschanskaja, 1954 using partial fragments of the 28S rDNA sequences is consistent with earlier phylogenies and the position of the Hirudinellidae Dollfus, 1932 is well-supported as a derived group most closely related to the Syncoeliidae Looss, 1899. PMID:24048751

  7. New species of Diplectanum (Monogenoidea:Diplectanidae), and proposal of a new genus of the Dactylogyridae from the gills of gerreid fishes (Teleostei) from Mexico and Panama.

    PubMed

    Franco, Edgar F Mendoza; Roche, Dominique G; Torchin, Mark E

    2008-09-01

    While investigating the parasites of several marine fishes from the Western Atlantic, the Southern Gulf of Mexico and Central America (Panama), the following monogenoidean species from the gills of gerreid fishes (Gerreidae) were found: Diplec-tanum gatunense sp. n. (Diplectanidae) and Octouncuhaptor eugerrei gen. et sp. n. (Dactylogyridae) in Eugerres brasilianus (Cuvier) from Gatun Lake in the Panama Canal Watershed, and Diplectanum mexicanum sp. n. in Diapterus rhombeus (Cuvier) from the coast of Campeche State, Mexico. New diplectanid species are distinguished from other species of the genus by the general morphology of the copulatory complex and by the shape of the anchors and bars on the haptor. Octouncuhaptor gen. n. is proposed for its new species having slightly overlapping gonads (testis posterodorsal to the ovary), a dextrolateral vaginal aperture, a copulatory complex consisting of a coiled male copulatory organ with counterclockwise rings with the base articulated to the accessory piece, 8 pairs of hooks and the absence of anchors and bars on haptor. Our analysis of morphological features of Diplectanum species on gerreids evidences that these parasites more closely resemble each other than the known species from sciaenids suggesting that split between gerreids and sciaenids resulted in parasite speciation. PMID:19202675

  8. Relative abundance and size of coastal sharks derived from commercial shark longline catch and effort data.

    PubMed

    Carlson, J K; Hale, L F; Morgan, A; Burgess, G

    2012-04-01

    In the north-west Atlantic Ocean, stock assessments conducted for some commercially harvested coastal sharks indicate declines from 64 to 80% with respect to virgin population levels. While the status of commercially important species is available, abundance trend information for other coastal shark species in the north-west Atlantic Ocean are unavailable. Using a generalized linear modelling (GLM) approach, a relative abundance index was derived from 1994 to 2009 using observer data collected in a commercial bottom longline fishery. Trends in abundance and average size were estimated for bull shark Carcharhinus leucas, spinner shark Carcharhinus brevipinna, tiger shark Galeocerdo cuvier and lemon shark Negaprion brevirostris. Increases in relative abundance for all shark species ranged from 14% for C. brevipinna, 12% for C. leucas, 6% for N. brevirostris and 3% for G. cuvier. There was no significant change in the size at capture over the time period considered for all species. While the status of shark populations should not be based exclusively on abundance trend information, but ultimately on stock assessment models, results from this study provide some cause for optimism on the status of these coastal shark species.

  9. Transversotrema Witenberg, 1944 (Trematoda: Transversotrematidae) from inshore fishes of Australia: description of a new species and significant range extensions for three congeners.

    PubMed

    Cutmore, Scott C; Diggles, Ben K; Cribb, Thomas H

    2016-09-01

    Four transversotrematid trematodes are reported from commercial teleost species in Australian waters. Transversotrema hunterae n. sp. is described from three species of Sillago Cuvier (Sillaginidae) from Moreton Bay, south-east Queensland. Molecular characterisation using ITS2 rDNA confirmed this stenoxenic specificity of Transversotrema hunterae n. sp., with identical sequence data from Sillago maculata Quoy & Gaimard, S. analis Whitley and S. ciliata Cuvier. Phylogenetic analysis, based on 28S rDNA data, demonstrates that T. hunterae n. sp. belongs to the 'Transversotrema licinum clade' and is most closely related to Transversotrema licinum Manter, 1970 and T. polynesiae Cribb, Adlard, Bray, Sasal & Cutmore, 2014, with the three species forming a well-supported clade in all analyses. We extend the known host and geographical ranges of three previously described Transversotrema species, T. licinum, T. elegans Hunter, Ingram, Adlard, Bray & Cribb, 2010 and T. espanola Hunter & Cribb, 2012. The new records represent significant range extensions for the three species and permit further examination of the patterns of biogeographical distribution in Australian waters. Host-specificity of Transversotrema species is examined, and the degree to which morphological analysis can inform taxonomic studies of this group is discussed. PMID:27522364

  10. Foraging Blainville's beaked whales (Mesoplodon densirostris) produce distinct click types matched to different phases of echolocation.

    PubMed

    Johnson, M; Madsen, P T; Zimmer, W M X; de Soto, N Aguilar; Tyack, P L

    2006-12-01

    Blainville's beaked whales (Mesoplodon densirostris Blainville) echolocate for prey during deep foraging dives. Here we use acoustic tags to demonstrate that these whales, in contrast to other toothed whales studied, produce two distinct types of click sounds during different phases in biosonar-based foraging. Search clicks are emitted during foraging dives with inter-click intervals typically between 0.2 and 0.4 s. They have the distinctive form of an FM upsweep (modulation rate of about 110 kHz ms(-1)) with a -10 dB bandwidth from 26 to 51 kHz and a pulse length of 270 micros, somewhat similar to chirp signals in bats and Cuvier's beaked whales (Ziphius cavirostris Cuvier), but quite different from clicks of other toothed whales studied. In comparison, the buzz clicks, produced in short bursts during the final stage of prey capture, are short (105 micros) transients with no FM structure and a -10 dB bandwidth from 25 to 80 kHz or higher. Buzz clicks have properties similar to clicks reported from large delphinids and hold the potential for higher temporal resolution than the FM clicks. It is suggested that the two click types are adapted to the separate problems of target detection and classification versus capture of low target strength prey in a cluttered acoustic environment.

  11. Could beaked whales get the bends? Effect of diving behaviour and physiology on modelled gas exchange for three species: Ziphius cavirostris, Mesoplodon densirostris and Hyperoodon ampullatus.

    PubMed

    Hooker, Sascha K; Baird, Robin W; Fahlman, Andreas

    2009-07-31

    A mathematical model, based on current knowledge of gas exchange and physiology of marine mammals, was used to predict blood and tissue tension N2 (P(N2)) using field data from three beaked whale species: northern bottlenose whales, Cuvier's beaked whales, and Blainville's beaked whales. The objective was to determine if physiology (body mass, diving lung volume, dive response) or dive behaviour (dive depth and duration, changes in ascent rate, diel behaviour) would lead to differences in P(N2) levels and thereby decompression sickness (DCS) risk between species. Diving lung volume and extent of the dive response had a large effect on end-dive P(N2). The dive profile had a larger influence on end-dive P(N2) than body mass differences between species. Despite diel changes in dive behaviour, P(N2) levels showed no consistent trend. Model output suggested that all three species live with tissue P(N2) levels that would cause a significant proportion of DCS cases in terrestrial mammals. Cuvier's beaked whale diving behaviour appears to put them at higher risk than the other species, which may explain their prevalence in strandings after the use of mid-frequency sonar.

  12. First records of parasitic copepods (Crustacea, Siphonostomatoida) from marine fishes in Korea.

    PubMed

    Venmathi Maran, B A; Soh, H Y; Hwang, U W; Chang, C Y; Myoung, J G

    2015-06-01

    The knowledge of the biodiversity of parasitic copepods in South Korea is increasing. Interestingly we report here, some parasitic copepods considered as the first record of findings from Korea. Nine species of parasitic copepods (Siphonostomatoida) including six genera of three different families [Caligidae (7), Lernaeopodidae (1), Lernanthropidae (1)] were recovered from eight species of wild fishes in Korea: 1) Caligus hoplognathi Yamaguti & Yamasu, 1959 (♀, ♂) from the body surface of barred knifejaw Oplegnathus fasciatus (Temminck & Schlegel); 2) Caligus lagocephali Pillai, 1961 (♀) from the gills of panther puffer Takifugu pardalis (Temminck & Schlegel); 3) Euryphorus brachypterus (Gerstaecker, 1853) (♀, ♂) from the opercular cavity of Atlantic bluefin tuna Thunnus thynnus (Linnaeus); 4) Euryphorus nordmanni Milne Edwards, 1840 (♀, ♂) from the opercular cavity of common dolphin fish Coryphaena hippurus Linnaeus; 5) Gloiopotes huttoni (Thomson) (♀, ♂) from the body surface of black marlin Istiompax indica (Cuvier); 6) Lepeophtheirus hapalogenyos Yamaguti & Yamasu, 1959 (♀) from the gill filaments of O. fasciatus; 7) Lepeophtheirus sekii Yamaguti, 1936 (♀, ♂) from the body surface of red seabream Pagrus major (Temminck & Schlegel); 8) Brachiella thynni Cuvier, 1830 (♀) from the body surface of longfin tuna or albacore Thunnus alalunga (Bonnaterre); 9) Lernanthropinus sphyraenae (Yamaguti & Yamasu, 1959) (♀) from the gill filaments of moon fish Mene maculata (Bloch & Schneider). Since the female was already reported in Korea, it is a new record for the male of C. hoplognathi. A checklist for the parasitic copepods of the family Caligidae, Lernaeopodidae and Lernanthropidae of Korea is provided. PMID:26691264

  13. Classification of echolocation clicks from odontocetes in the Southern California Bight.

    PubMed

    Roch, Marie A; Klinck, Holger; Baumann-Pickering, Simone; Mellinger, David K; Qui, Simon; Soldevilla, Melissa S; Hildebrand, John A

    2011-01-01

    This study presents a system for classifying echolocation clicks of six species of odontocetes in the Southern California Bight: Visually confirmed bottlenose dolphins, short- and long-beaked common dolphins, Pacific white-sided dolphins, Risso's dolphins, and presumed Cuvier's beaked whales. Echolocation clicks are represented by cepstral feature vectors that are classified by Gaussian mixture models. A randomized cross-validation experiment is designed to provide conditions similar to those found in a field-deployed system. To prevent matched conditions from inappropriately lowering the error rate, echolocation clicks associated with a single sighting are never split across the training and test data. Sightings are randomly permuted before assignment to folds in the experiment. This allows different combinations of the training and test data to be used while keeping data from each sighting entirely in the training or test set. The system achieves a mean error rate of 22% across 100 randomized three-fold cross-validation experiments. Four of the six species had mean error rates lower than the overall mean, with the presumed Cuvier's beaked whale clicks showing the best performance (<2% error rate). Long-beaked common and bottlenose dolphins proved the most difficult to classify, with mean error rates of 53% and 68%, respectively. PMID:21303026

  14. Habitat use and preferences of cetaceans along the continental slope and the adjacent pelagic waters in the western Ligurian Sea

    NASA Astrophysics Data System (ADS)

    Azzellino, A.; Gaspari, S.; Airoldi, S.; Nani, B.

    2008-03-01

    The physical habitat of cetaceans occurring along the continental slope in the western Ligurian Sea was investigated. Data were collected from two different sighting platforms, one of the two being a whale-watching boat. Surveys, conducted from May to October and from 1996 to 2000, covered an area of approximately 3000 km 2 with a mean effort of about 10,000 km year -1. A total of 814 sightings was reported, including all the species occurring in the area: Stenella coeruleoalba, Balaenoptera physalus, Physeter macrocephalus, Globicephala melas, Grampus griseus, Ziphius cavirostris, Tursiops truncatus, Delphinus delphis. A Geographic Information System was used to integrate sighting data to a set of environmental characteristics, which included bottom gradient, area between different isobaths, and length and linearity of the isobaths within a cell unit. Habitat use was analysed by means of a multi-dimensional scaling, MDS, analysis. Significant differences were found in the habitat preference of most of the species regularly occurring in the area. Bottlenose dolphin, Risso's dolphin, sperm whale and Cuvier's beaked whale were found strongly associated to well-defined depth and slope gradient characteristics of the shelf-edge and the upper and lower slope. The hypothesis of habitat segregation was considered for Risso's dolphin, sperm whale and Cuvier's beaked whale. Canonical discriminant functions using depth and slope as predictors outlined clear and not overlapping habitat preferences for Risso's dolphin and Cuvier's beaked whale, whereas a partial overlapping of the habitat of the other two species was observed for sperm whale. Such a partitioning of the upper and lower slope area may be the result of the common feeding habits and suggests a possible competition of these three species. A temporal segregation in the use of the slope area was also observed for sperm whales and Risso's dolphins. Fin whales, and the occasionally encountered common dolphin and long

  15. New records of Porrocaecum sp. and Hysterothylacium sp. (Nematoda: Anisakidae) from fishes of Bay of Bengal.

    PubMed

    Lakshmi, I R; Rao, K H; Shyamasundary, K

    1990-01-01

    The present paper deals with new records of nematoda of the family Anisakidae Railliet et Henry, 1912. During a study of the parasites of marine fishes (shark, ray and marine teleosts) of Bay of Bengal, females of interesting nematode parasites were found in stomach and body cavity of Chiloscyllium indicum (Gmelin), Torpedo panthera (Olfers), Pomadasys masculatus Bloch and Sphyraena obtusata Cuvier from Visakhapatnam, Bheemunipatnam and Yarada (Andhra Pradesh). Most of the characters tally with Porrocaecum galeocerdonis and Hysterothylacium engraulisi, except for minor variations. Because of the non-availability of the male, it is not possible to assign the present specimens to any of the known species of the genera Porrocaecum and Hysterothylacium. Hence these are referred as Porrocaecum sp. and Hysterothylacium sp. Chiloscyllium indicum and Torpedo panthera are new host records. Visakhapatnam, Bheemunipatnam and Yarada are the new locality records. PMID:2152367

  16. Hysterothylacium pseudotumbili n.sp. (Nematoda: Anisakidae) from the marine fishes of Visakhapatnam, Bay of Bengal.

    PubMed

    Lakshmi, I R; Rao, K H; Shyamasundari, K

    1991-01-01

    Hysterothylacium pseudotumbili n.sp. from the stomach and body cavity of marine fishes. Chrorinemus tol Couvier. Saurida undosquamis (Richardson), Lutianus russelli (Bleeker), Rastrilliger kanagurta (Cuvier) and Saurida pseudotumbili Dutt and Vidyasagar collected from Visakhapatnam (Bay of Bengal) is described and figured. A detailed examination has allowed us to erect a new species of Hysterothylacium to accommodate the worm. It shows remarkable differences from other known species of Hysterothylacium in respect of body measurements, the papillae on the lips arrangement, location of nerve ring and excretory pore, long intestinal caecum, position of vulva, number and arrangement of caudal papillae and size of the spicules. The new species is designated as Hysterothylacium pseudotumbili. Saurida pseudotumbili is the new host record. This is the first report of the genus in this host. Visakhapatnam coast is the new locality record. PMID:1844137

  17. Larvae of Contracaecum sp. (Nematoda: Anisakidae) in the threatened freshwater fish Sandelia capensis (Anabantidae) in South Africa.

    PubMed

    Moravec, Franti Ek; van Rensburg, Candice Jansen; Van As, Liesl L

    2016-08-01

    Third-stage larvae of the nematode genus Contracaecum Railliet et Henry, 1912 (Contracaecum sp.) were, for the first time, recorded from the abdominal cavity of the threatened endemic freshwater fish Sandelia capensis (Cuvier) in South Africa. The larval morphology indicated that they belong to a species of which the adults are parasitic in fish-eating birds. Although the nematode seems to be a common parasite of S. capensis in the locality under study (prevalence 23%), the low intensity of infection recorded (1 to 4) and the generally known low pathogenicity of Contracaecum larvae in fish indicate that this parasite probably does not represent a danger to the local population of this threatened fish species. PMID:27503922

  18. Description and redescription of Haliotrema species (Monogenoidea: Poloyonchoinea: Dactylogyridae) parasitizing butterfly fishes (Teleostei: Chaetodontidae) in the Indo-West Pacific Ocean.

    PubMed

    Plaisance, Laetitia; Bouamer, Salah; Morand, Serge

    2004-05-01

    Haliotrema species are described and/or reported from the gills of butterfly fishes (Chaetodontidae) from coral reefs of the Indo-West Pacific islands: Moorea (French Polynesia), Palau (Micronesia), Wallis (Wallis and Futuna), New Caledonia, Lizard Island and Heron Island (Great Barrier Reef, Australia). Haliotrema angelopterum sp. nov., a new species of Monogenoidea parasite from seven species of Chaetodon Linnaeus, 1758 (Chaetodontidae), is described. A new redescription and statute are given for Haliotrema aurigae (Yamaguti, 1968) comb. nov., a parasite from ten species of Chaetodon and one species of Heniochus Cuvier, 1816 (Chaetodontidae). New records of Haliotrema scyphovagina Yamaguti, 1968 are reported from two localities and from several host species belonging to the genera Chaetodon and Forcipiger Jordan and McGregor, 1898 (Chaetodontidae).

  19. Gideon Mantell and the Discovery of Dinosaurs

    NASA Astrophysics Data System (ADS)

    Dean, Dennis R.

    1999-01-01

    Gideon Mantell and the Discovery of Dinosaurs is a scholarly yet accessible biography--the first in a generation--of a pioneering dinosaur hunter and scholar. Gideon Mantell discovered the Iguanodon (a famous tale set right in this book) and several other dinosaur species, spent over twenty-five years restoring Iguanodon fossils, and helped establish the idea of an Age of Reptiles that ended with their extinction at the conclusion of the Mesozoic Era. He had significant interaction with such well-known figures as James Parkinson, Georges Cuvier, Charles Lyell, Roderick Murchison, Charles Darwin, and Richard Owen. Dennis Dean, a well-known scholar of geology and the Victorian era, here places Mantell's career in its cultural context, employing original research in archives throughout the world, including the previously unexamined Mantell family papers in New Zealand.

  20. Microsatellite loci in the tiger shark and cross-species amplification using pyrosequencing technology.

    PubMed

    Mendes, Natália J; Cruz, Vanessa P; Ashikaga, Fernando Y; Camargo, Sâmia M; Oliveira, Claudio; Piercy, Andrew N; Burgess, George H; Coelho, Rui; Santos, Miguel N; Mendonça, Fernando F; Foresti, Fausto

    2016-01-01

    The tiger shark (Galeocerdo cuvier) has a global distribution in tropical and warm temperate seas, and it is caught in numerous fisheries worldwide, mainly as bycatch. It is currently assessed as near threatened by the International Union for Conservation of Nature (IUCN) Red List. In this study, we identified nine microsatellite loci through next generation sequencing (454 pyrosequencing) using 29 samples from the western Atlantic. The genetic diversity of these loci were assessed and revealed a total of 48 alleles ranging from 3 to 7 alleles per locus (average of 5.3 alleles). Cross-species amplification was successful at most loci for other species such as Carcharhinus longimanus, C. acronotus and Alopias superciliosus. Given the potential applicability of genetic markers for biological conservation, these data may contribute to the population assessment of this and other species of sharks worldwide. PMID:27635306

  1. Conflict resolution of grammar and gender for avian species-group names under Article 31.2.2 of the ICZN Code: is gender agreement worth it?

    PubMed

    Schodde, Richard; Bock, Walter

    2016-01-01

    We analyze recent nomenclatural treatment of selected avian species-group names that may be either adjective and variable or noun and invariable. In 27 such names, we found that 14 previously identified as adjectives are nouns under Article 31.2.2 of the International Code of Zoological Nomenclature. Five of them may require correction in current checklists; they are bresilius in Ramphocelus bresilius (Linnaeus, 1766) to bresilia, germana in Amblyornis macgregoriae germana Rothschild, 1910 to germanus, argentinus in Muscisaxicola cinereus argentinus Hellmayr, 1932 to argentina, martinicus in Porphyrio martinicus (Linnaeus, 1766) to martinica, and moluccus in Threskiornis moluccus (Cuvier, 1829) to molucca. Mindful of the compounding effect of species-genus recombination from taxonomic revision, we reach the conclusion, not new, that the requirement for gender agreement in species-group names is the single biggest cause of nomenclatural instability in zoology. To resolve it, we support replacing gender agreement by original spellings for species-group names. PMID:27395618

  2. A new Huffmanela species, H. schouteni sp. n. (Nematoda: Trichosomoididae) from flying fishes in Curaçao.

    PubMed

    Moravec, F; Campbell, B G

    1991-01-01

    A new nematode species, Huffmanela schouteni sp. n., has been established on the basis of its egg morphology and biological characters (adult nematodes are unknown). The dark-shelled eggs of this histozoic parasite occur in masses in the abdominal cavity, serose covers of internal organs and in the liver of the flying fishes Hirundichthys affinis Günther (type host) and Cypselurus cyanopterus Cuvier et Valenciennes in Curaçao. The eggs of H. schouteni sp. n. differ from those in other congeneric species mainly in the absence of small spines on the surface of the transparent envelope enclosing the egg proper, measurements (size of eggs 0.069-0.075 x 0.027-0.030 mm) and their localization in the host. A key to Huffmanela species based on egg morphology has been provided.

  3. Ticks parasitizing reptiles in the Bahamas.

    PubMed

    Durden, L A; Knapp, C R

    2005-09-01

    Two species of reptile ticks, Amblyomma dissimile Koch and Amblyomma torrei Pérez Vigueras (Acari: Ixodidae), are reported from the Bahama Islands for the first time. The widespread neotropical (including the Caribbean and southern Florida) A. dissimile was recovered on Andros Island from three species of reptiles all for the first time: the Andros iguana Cyclura cychlura cychlura Cuvier, the Andros curly tail lizard Leiocephalus carinatus coryi Schmidt, and the Andros boa Epicrates striatus fowleri Sheplan and Schwartz. The iguana tick A. torrei, previously known only from Cuba, Puerto Rico and the Cayman Islands, was recovered in the Exuma Islands from the Exuma iguana Cyclura cychlura figginsi Barbour. Mean numbers of ticks per host were as high as 36.6 on Mangrove Cay, Andros Island, and 25.8 on Pasture Cay in the Exuma Islands.

  4. Copepods of Hatschekiidae (Copepoda, Siphonostomatoida) new to Korean fauna, with description of a new species

    NASA Astrophysics Data System (ADS)

    Moon, Seong Yong; Kim, Il-Hoi

    2013-03-01

    Eight species of the Hatschekiidae are recorded as parasites of marine fishes from southern coast of Korea. One new species, Hatschekia jejuensis, parasitic on Cheilodactylus zonatus Cuvier is included. The remaining seven species are new to Korean fauna: Hatschekia iridescens Wilson, 1913, H. japonica Jones, 1985, H. monacanthi Yamaguti, 1939, H. tenuis (Heller, 1865) H. pseudolabri Yamaguti, 1953, H. cylindrica Shiino, 1957, and Pseudocongericola chefoonensis Yü, 1933. Hatschekia jejuensis n. sp. has a combination of characteristics in the female where the trunk is 2.35 times as long as the cephalothorax and displays a pair of posterolateral bulges on both sides, the antennules is 5-segmented, the mandible bears six teeth, and the armature formulae of the legs are I-0; III (exopod) and 0-0; II (endopod) for leg 1 and I-0; I (exopod) and 0-0; II (endopod) for leg 2.

  5. Similascarophis n. gen. n. spp. (Nematoda: Cystidicolidae) parasitizing marine fishes off the Chilean coast.

    PubMed

    Muñoz, Gabriela; González, María Teresa; George-Nascimento, Mario

    2004-08-01

    Similascarophis (Cystidicolidae) n. gen. is proposed. In the mouth of specimens of this genus, submedial labia are absent and pseudolabia do not have any part projecting toward the central oral opening. These nematodes were obtained from the alimentary tract of 7 marine fish species along the coast of Chile: Bovichthys chilensis Regan, Eleginops maclovinus (Cuvier), Pinguipes chilensis (Valenciennes), Cilus gilberti (Abbott), Cheilodactylus variegatus Valenciennes, Girella laevifrons (Tschudi), and Graus nigra Philippi. Morphology and morphometry are compared between 2 new Similascarophis species: Similascarophis maulensis n. sp. and S. chilensis n. sp., which differ in the presence of sublabia and in the length of the glandular esophagus and left spicule. We also recorded Similascarophis sp. in 2 other host species, which showed some distinct proportional measurements, although these differences were not sufficiently clear to identify them as a new species.

  6. Protopithecus: rediscovering the first fossil primate.

    PubMed

    Hartwig, W C

    1995-01-01

    The earliest discoveries of extinct primates and humans profoundly affected the course of evolutionary theory as a scientific model for explaining life and its diversity through time. The absence of such fossils in the early nineteenth century provided important negative evidence to the competing French intellectual schools of Lamarckian evolutionism and Cuvierian catastrophism. Indeed, the first recognition of extinct primates fell serendipitously between the death of Cuvier in 1832 and the revolutionary writings of Darwin in 1859. Largely unknown to history, however, is that four different European scholars, working on three continents, independently discovered and recognized extinct primates within a few months of each other in 1836. The first of these to be formally named, Protopithecus, is ironically the least well known despite being the largest monkey ever discovered in the western hemisphere. The reasons for this forgotten first discovery reflect a general unawareness of South American mammals, and propagation of misinterpretation at a critical time in the history of primatology.

  7. Genetic structure of Octopus vulgaris (Cephalopoda, Octopodidae) in the central Mediterranean Sea inferred from the mitochondrial COIII gene.

    PubMed

    Fadhlaoui-Zid, Karima; Knittweis, Leyla; Aurelle, Didier; Nafkha, Chaala; Ezzeddine, Soufia; Fiorentino, Fabio; Ghmati, Hisham; Ceriola, Luca; Jarboui, Othman; Maltagliati, Ferruccio

    2012-01-01

    The polymorphism of the mitochondrial gene cytochrome oxidase III was studied in the Mediterranean octopus, Octopus vulgaris Cuvier, 1797. A total of 202 specimens from seven sampling sites were analysed with the aim of elucidating patterns of genetic structure in the central Mediterranean Sea and to give an insight into the phylogeny of the Octopus genus. Phylogenetic analyses showed that individuals from the central Mediterranean belong to the O. vulgaris species whose limits should nevertheless be clarified. Concerning genetic structure, two high-frequency haplotypes were present in all locations. The overall genetic divergence (Φ(ST)=0.05, P<0.05) indicated a significant genetic structuring in the study area and an AMOVA highlighted a significant break between western and eastern Mediterranean basins (Φ(CT)=0.094, P<0.05). Possible explanations for the observed patterns of genetic structuring are discussed with reference to their relevance for fisheries management.

  8. The cercaria of Galactosomum bearupi Pearson, 1973 (Trematoda: Heterophyidae) at Heron and Masthead Islands, Great Barrier Reef, Australia.

    PubMed

    Beuret, J; Scott, D A; Pearson, J C

    2000-05-01

    Magnacercous cercariae, all morphologically identical but with different coloured tails, were found naturally infecting the intertidal prosobranch gastropod Clypeomorus batillariaeformis Habe & Kosuge (Cerithiidae) at Heron and Masthead Islands. Several species of coral-dwelling fishes were exposed to magnacercous cercariae. Active ingestion by the fish, followed by the complete development of the metacercaria in the optic lobes, occurred in Pomacentrus molluccensis Bleeker, but not in Dascyllus aruanus (L.), where development stopped short after encystment. All cercariae turned out to belong to the same species, Galactosomum bearupi Pearson, 1973. Natural infections of G. bearupi metacercariae were found in eight species of fish at Heron Island: Pomacentrus molluccensis, P. wardi Whitley, P. bankanensis Bleeker, P. flavicauda Whitley, Stegastes cf. fasciolatus (Ogilby), Sillago maculata Quoy & Gaimard, S. cf. ciliata Cuvier and Crenimugil crenilabris (Forsskål). This represents the fourth account of the cercaria of a species of Galactosomum.

  9. Aerial surveys of endangered cetaceans and other marine mammals in the northwestern Gulf of Alaska and southeastern Bering Sea. Final report

    SciTech Connect

    Brueggeman, J.J.; Green, G.A.; Grotefendt, R.A.; Chapman, D.G.

    1987-09-01

    Aerial surveys were conducted in the Northwestern Gulf of Alaska and southeastern Bering Sea to determine the abundance, distribution, and habitat use patterns of endangered cetaceans and other marine mammals. Four species of cetaceans listed by the Federal Government as endangered were observed: gray, humpback, finback, and sperm whales. Sightings were also made to seven nonendangered species of cetaceans: minke, Cuvier's beaked, Baird's beaked, belukha, and killer whales, and Dall and harbor porpoises. Results show that the project area is an important feeding ground for relatively large numbers of humpback and finback whales and lower numbers of gray whale migration route between seasonal ranges. The project area also supports a variety of other marine mammals both seasonally and annually.

  10. Microsatellite loci in the tiger shark and cross-species amplification using pyrosequencing technology

    PubMed Central

    Mendes, Natália J.; Cruz, Vanessa P.; Ashikaga, Fernando Y.; Camargo, Sâmia M.; Oliveira, Claudio; Piercy, Andrew N.; Burgess, George H.; Coelho, Rui; Santos, Miguel N.; Foresti, Fausto

    2016-01-01

    The tiger shark (Galeocerdo cuvier) has a global distribution in tropical and warm temperate seas, and it is caught in numerous fisheries worldwide, mainly as bycatch. It is currently assessed as near threatened by the International Union for Conservation of Nature (IUCN) Red List. In this study, we identified nine microsatellite loci through next generation sequencing (454 pyrosequencing) using 29 samples from the western Atlantic. The genetic diversity of these loci were assessed and revealed a total of 48 alleles ranging from 3 to 7 alleles per locus (average of 5.3 alleles). Cross-species amplification was successful at most loci for other species such as Carcharhinus longimanus, C. acronotus and Alopias superciliosus. Given the potential applicability of genetic markers for biological conservation, these data may contribute to the population assessment of this and other species of sharks worldwide. PMID:27635306

  11. Microsatellite loci in the tiger shark and cross-species amplification using pyrosequencing technology

    PubMed Central

    Mendes, Natália J.; Cruz, Vanessa P.; Ashikaga, Fernando Y.; Camargo, Sâmia M.; Oliveira, Claudio; Piercy, Andrew N.; Burgess, George H.; Coelho, Rui; Santos, Miguel N.; Foresti, Fausto

    2016-01-01

    The tiger shark (Galeocerdo cuvier) has a global distribution in tropical and warm temperate seas, and it is caught in numerous fisheries worldwide, mainly as bycatch. It is currently assessed as near threatened by the International Union for Conservation of Nature (IUCN) Red List. In this study, we identified nine microsatellite loci through next generation sequencing (454 pyrosequencing) using 29 samples from the western Atlantic. The genetic diversity of these loci were assessed and revealed a total of 48 alleles ranging from 3 to 7 alleles per locus (average of 5.3 alleles). Cross-species amplification was successful at most loci for other species such as Carcharhinus longimanus, C. acronotus and Alopias superciliosus. Given the potential applicability of genetic markers for biological conservation, these data may contribute to the population assessment of this and other species of sharks worldwide.

  12. Three new gonad-infecting species of Philometra (Nematoda: Philometridae) parasitic in Lutjanus spp. (Lutjanidae) in the northern Gulf of Mexico off Florida, USA.

    PubMed

    Moravec, Frantisek; Bakenhaster, Micah; Fajer-Avila, Emma J

    2014-08-01

    Based on light and scanning electron microscopical studies, three new gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) are described from marine fishes of the genus Lutjanus Bloch (Perciformes: Lutjanidae) in the northern Gulf of Mexico: P. longispicula sp. n. from the ovary of the northern red snapper L. campechanus (Poey) (type host) and silk snapper L. vivanus (Cuvier); P. latispicula sp. n. from the ovary and rarely testes of the grey snapper L. griseus (Linnaeus); and P. synagridis sp. n. (only males available) from the ovary of the lane snapper Lutjanus synagris (Linnaeus). These species are mainly characterised by the lengths of spicules (378-690 microm, 135-144 microm and 186-219 microm, respectively) and spicule shapes, structure of the distal portion of the gubernaculum and the structure of the male caudal end. These are the first valid, nominal species of gonad-infecting philometrids reported from fishes of the family Lutjanidae in the western Atlantic region.

  13. Systemic herpesvirus and morbillivirus co-infection in a striped dolphin (Stenella coeruleoalba).

    PubMed

    Soto, S; González, B; Willoughby, K; Maley, M; Olvera, A; Kennedy, S; Marco, A; Domingo, M

    2012-01-01

    During 2007 a dolphin morbillivirus epizootic affected the western Mediterranean and several striped dolphins (Stenella coeruleoalba) stranded on the Catalonian coasts. One of those animals had severe lymphoid depletion, necrosis and syncytial formation in lymph nodes and spleen, with large basophilic nuclear inclusions compatible with herpesvirus detected by immunohistochemical and ultrastructural examination. Non-suppurative encephalitis with associated morbillivirus antigen and morbillivirus antigen within alveolar macrophages were also observed. A pan-herpesvirus nested polymerase chain reaction amplified a sequence virtually identical to two cetacean herpesvirus sequences previously identified in systemic infections in an Atlantic Cuvier's beaked whale (Ziphius cavirostris) and in a Mediterranean striped dolphin. The herpesviral infection was probably secondary to the immunosuppression caused by the morbillivirus. To our knowledge, this is the first report of a cetacean co-infected by dolphin morbillivirus and herpesvirus with evidence of lesions attributable to both viruses.

  14. Rebuttal to Koeda et al. (2014) on the Red Sea fishes of the perciform genus Pempheris.

    PubMed

    Randall, John E; Victor, Benjamin C; Alpermann, Tilman J; Bogorodsky, Sergey V; Mal, Ahmad O; Satapoomin, Ukkrit; Bineesh, K K

    2014-01-01

    Koeda et al. (2014) published a review of fishes of the genus Pempheris of the Red Sea. They concluded that there are four species: P. adusta Bleeker, P. mangula Cuvier, P. nesogallica Cuvier, and a new species, P. tominagai. We show that the first three species they cite are not present in the Red Sea, as follows. 1) P. adusta is a western Pacific species (type locality Ambon), described only from the holotype, and without a dark border on the anal fin. Koeda et al. (2014) mistakenly apply that name to P. flavicycla which is a widespread Indian Ocean species characterized by a prominent broad black border along the anal fin. Koeda et al. (2014) also redescribe P. adusta, using Indian Ocean specimens of P. flavicycla, despite the coloration difference and a 2.5% difference in the mtDNA sequence (COI) between Indian Ocean and W. Pacific populations. 2) P. mangula is a species from the east coast of India (type locality Visakhapatnam), clearly distinct in both gill-raker counts and a 1.1% sequence divergence in COI from its Red Sea relative P. rhomboidea. Pempheris mangula is not found west of India, and Koeda et al. (2014) mistakenly use DNA from Oman and Madagascar to represent P. mangula, instead of genetic material available from the type locality. 3) Pempheris nesogallica (type locality Mauritius) is unknown from the Red Sea. Koeda et al. (2014) separate P. nesogallica from P. rhomboidea (their "P. mangula") by eye size; we fail to find any difference (and they use their purported eye-size difference to erroneously rename one of the two syntypes of P. nesogallica as "P. mangula"). 4) Their new species P. tominagai is referred to as the Indian Ocean sister species of "P. schwenkii of the Pacific"; however, the type locality of P. schwenkii is the Batu Islands off the SW coast of Sumatra in the Indian Ocean. They mistakenly include specimens of a distant South African species as paratypes of P. tominagai. We have determined that P. tominagai is a valid species

  15. Redescription and genetic characterization of Hysterothylacium thalassini Bruce, 1990 (Nematoda: Anisakidae) from marine fishes in the South China Sea.

    PubMed

    Liu, Yuan-Yuan; Xu, Zhen; Zhang, Lu-Ping; Li, Liang

    2013-08-01

    Hysterothylacium thalassini Bruce, 1990, was redescribed using light microscopy and, for the first time, scanning electron microscopy based on newly collected specimens from the marine fishes Priacanthus tayenus Richardson and Pricanthus macracanthus Cuvier (Perciformes: Priacanthidae) in the South China Sea. Previously unreported or inaccurately described morphological features of taxonomic significance are described, including the number and morphology of paracloacal and postcloacal papillae, the morphology of the vulva, and the presence of small phasmids in the both sexes. Moreover, specimens of H. thalassini collected from the 2 hosts were characterized by sequencing and analyzing the internal transcribed spacer (ITS) of the ribosomal DNA. The ITS region of H. thalassini was compared with Hysterothylacium spp. in GenBank, and the results seem to support the validity of the incompletely known species. PMID:23343397

  16. Trianchoratus longianchoratus sp. n. (Monogenea: Ancyrocephalidae: Heteronchocleidinae) from Channa lucius (Osteichthyes: Channidae) in Peninsular Malaysia.

    PubMed

    Tan, W B; Lim, L H S

    2009-09-01

    One new and three previously described species of Trianchoratus Price et Berry, 1966 were collected from the gills of Channa lucius (Cuvier) and Channa striata (Bloch) from the Bukit Merah Reservoir, Perak and Endau-Rompin, Pahang, Peninsular Malaysia. They are Trianchoratus longianchoratus sp.n., T. malayensis Lim, 1986 and T. pahangensis Lim, 1986 from C. lucius, and T. ophicephali Lim, 1986 from C. striata. The new species differs from the Trianchoratus species hitherto described from channids and anabantoids in having two ventral anchors with a long curved inner root and one dorsal anchor with a curved inner root and lacking an outer root. A table summarizing the known species of heteronchocleidins (Trianchoratus, Eutrianchoratus and Heteronchocleidus) and Sundanonchus reported from fish hosts of different families (Channidae, Helostomatidae, Anabantidae and Osphronemidae) is provided. PMID:19827361

  17. Redescription and genetic characterization of Hysterothylacium thalassini Bruce, 1990 (Nematoda: Anisakidae) from marine fishes in the South China Sea.

    PubMed

    Liu, Yuan-Yuan; Xu, Zhen; Zhang, Lu-Ping; Li, Liang

    2013-08-01

    Hysterothylacium thalassini Bruce, 1990, was redescribed using light microscopy and, for the first time, scanning electron microscopy based on newly collected specimens from the marine fishes Priacanthus tayenus Richardson and Pricanthus macracanthus Cuvier (Perciformes: Priacanthidae) in the South China Sea. Previously unreported or inaccurately described morphological features of taxonomic significance are described, including the number and morphology of paracloacal and postcloacal papillae, the morphology of the vulva, and the presence of small phasmids in the both sexes. Moreover, specimens of H. thalassini collected from the 2 hosts were characterized by sequencing and analyzing the internal transcribed spacer (ITS) of the ribosomal DNA. The ITS region of H. thalassini was compared with Hysterothylacium spp. in GenBank, and the results seem to support the validity of the incompletely known species.

  18. Species distribution models of tropical deep-sea snappers.

    PubMed

    Gomez, Céline; Williams, Ashley J; Nicol, Simon J; Mellin, Camille; Loeun, Kim L; Bradshaw, Corey J A

    2015-01-01

    Deep-sea fisheries provide an important source of protein to Pacific Island countries and territories that are highly dependent on fish for food security. However, spatial management of these deep-sea habitats is hindered by insufficient data. We developed species distribution models using spatially limited presence data for the main harvested species in the Western Central Pacific Ocean. We used bathymetric and water temperature data to develop presence-only species distribution models for the commercially exploited deep-sea snappers Etelis Cuvier 1828, Pristipomoides Valenciennes 1830, and Aphareus Cuvier 1830. We evaluated the performance of four different algorithms (CTA, GLM, MARS, and MAXENT) within the BIOMOD framework to obtain an ensemble of predicted distributions. We projected these predictions across the Western Central Pacific Ocean to produce maps of potential deep-sea snapper distributions in 32 countries and territories. Depth was consistently the best predictor of presence for all species groups across all models. Bathymetric slope was consistently the poorest predictor. Temperature at depth was a good predictor of presence for GLM only. Model precision was highest for MAXENT and CTA. There were strong regional patterns in predicted distribution of suitable habitat, with the largest areas of suitable habitat (> 35% of the Exclusive Economic Zone) predicted in seven South Pacific countries and territories (Fiji, Matthew & Hunter, Nauru, New Caledonia, Tonga, Vanuatu and Wallis & Futuna). Predicted habitat also varied among species, with the proportion of predicted habitat highest for Aphareus and lowest for Etelis. Despite data paucity, the relationship between deep-sea snapper presence and their environments was sufficiently strong to predict their distribution across a large area of the Pacific Ocean. Our results therefore provide a strong baseline for designing monitoring programs that balance resource exploitation and conservation planning, and

  19. Species Distribution Models of Tropical Deep-Sea Snappers

    PubMed Central

    Gomez, Céline; Williams, Ashley J.; Nicol, Simon J.; Mellin, Camille; Loeun, Kim L.; Bradshaw, Corey J. A.

    2015-01-01

    Deep-sea fisheries provide an important source of protein to Pacific Island countries and territories that are highly dependent on fish for food security. However, spatial management of these deep-sea habitats is hindered by insufficient data. We developed species distribution models using spatially limited presence data for the main harvested species in the Western Central Pacific Ocean. We used bathymetric and water temperature data to develop presence-only species distribution models for the commercially exploited deep-sea snappers Etelis Cuvier 1828, Pristipomoides Valenciennes 1830, and Aphareus Cuvier 1830. We evaluated the performance of four different algorithms (CTA, GLM, MARS, and MAXENT) within the BIOMOD framework to obtain an ensemble of predicted distributions. We projected these predictions across the Western Central Pacific Ocean to produce maps of potential deep-sea snapper distributions in 32 countries and territories. Depth was consistently the best predictor of presence for all species groups across all models. Bathymetric slope was consistently the poorest predictor. Temperature at depth was a good predictor of presence for GLM only. Model precision was highest for MAXENT and CTA. There were strong regional patterns in predicted distribution of suitable habitat, with the largest areas of suitable habitat (> 35% of the Exclusive Economic Zone) predicted in seven South Pacific countries and territories (Fiji, Matthew & Hunter, Nauru, New Caledonia, Tonga, Vanuatu and Wallis & Futuna). Predicted habitat also varied among species, with the proportion of predicted habitat highest for Aphareus and lowest for Etelis. Despite data paucity, the relationship between deep-sea snapper presence and their environments was sufficiently strong to predict their distribution across a large area of the Pacific Ocean. Our results therefore provide a strong baseline for designing monitoring programs that balance resource exploitation and conservation planning, and

  20. Lessons learnt from the Indian Ocean Tsunami 2004: the role of surface and subsurface topography in deep water tsunami propagation

    NASA Astrophysics Data System (ADS)

    Pattiaratchi, C. B.

    2014-12-01

    The Indian Ocean experienced its most devastating natural disaster through the action of a Tsunami, resulting from of an earthquake off the coast of Sumatra on 26th of December 2004. This resulted in widespread damage both to property and human lives with over 250,000 deaths in the region and many millions homeless. Our understanding of tsunami generation and propagation has increased significantly over the past decade. In this presentation, results obtained from detailed analysis of sea level data from Western Australia and Sri Lanka together with numerical modelling are presented to highlight the effects of topography both at the surface and subsurface. The major effects are due to wave reflection and refraction. Examples of wave reflection include: impacts on Malaysia/Thailand, Sri Lanka and Western Australia due to wave reflection from Sri Lanka, Maldives and Mascarene Ridge, respectively. In the case of Sri Lanka, the maximum wave height recorded along the west coast during the 2004 tsunami was due to the reflected wave from Maldives impacting 3 hours after the arrival of the initial waves. Similarly, along the West coast of Australia highest waves occurred 15 hours after the arrival of the first wave. Here, based on travel times, we postulate that the waves were reflected from the Mascarene Ridge and/or the island of Madagascar (Figure 1b). The conclusions based on observations were verified using numerical model simulations using the MOST and ComMIT models. Numerical modelling using the MOST model indicated the role of offshore susurface topography on tsunami propagation through wave wave refraction. Examples of wave refraction included the effects of deep water seamounts (Venin Meinesz) and plateaus (Wallaby, Cuvier and Exmouth) on tsunami propagation along the West Australian coast. The tsunami waves are first scattered by the Venin Meinesz seamounts and were then refracted by the Wallaby and Cuvier plateaus resulting in waves being deflected onto the

  1. Quantifying Shark Distribution Patterns and Species-Habitat Associations: Implications of Marine Park Zoning

    PubMed Central

    Espinoza, Mario; Cappo, Mike; Heupel, Michelle R.; Tobin, Andrew J.; Simpfendorfer, Colin A.

    2014-01-01

    Quantifying shark distribution patterns and species-specific habitat associations in response to geographic and environmental drivers is critical to assessing risk of exposure to fishing, habitat degradation, and the effects of climate change. The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS) along the entire Great Barrier Reef Marine Park (GBRMP) over a ten year period. Overall, 21 species of sharks from five families and two orders were recorded. Grey reef Carcharhinus amblyrhynchos, silvertip C. albimarginatus, tiger Galeocerdo cuvier, and sliteye Loxodon macrorhinus sharks were the most abundant species (>64% of shark abundances). Multivariate regression trees showed that hard coral cover produced the primary split separating shark assemblages. Four indicator species had consistently higher abundances and contributed to explaining most of the differences in shark assemblages: C. amblyrhynchos, C. albimarginatus, G. cuvier, and whitetip reef Triaenodon obesus sharks. Relative distance along the GBRMP had the greatest influence on shark occurrence and species richness, which increased at both ends of the sampling range (southern and northern sites) relative to intermediate latitudes. Hard coral cover and distance across the shelf were also important predictors of shark distribution. The relative abundance of sharks was significantly higher in non-fished sites, highlighting the conservation value and benefits of the GBRMP zoning. However, our results also showed that hard coral cover had a large effect on the abundance of reef-associated shark species, indicating that coral reef health may be important for the success of marine protected areas. Therefore, understanding shark distribution patterns, species-habitat associations, and the drivers responsible for those patterns is essential for developing sound management and conservation approaches. PMID

  2. Quantifying shark distribution patterns and species-habitat associations: implications of marine park zoning.

    PubMed

    Espinoza, Mario; Cappo, Mike; Heupel, Michelle R; Tobin, Andrew J; Simpfendorfer, Colin A

    2014-01-01

    Quantifying shark distribution patterns and species-specific habitat associations in response to geographic and environmental drivers is critical to assessing risk of exposure to fishing, habitat degradation, and the effects of climate change. The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS) along the entire Great Barrier Reef Marine Park (GBRMP) over a ten year period. Overall, 21 species of sharks from five families and two orders were recorded. Grey reef Carcharhinus amblyrhynchos, silvertip C. albimarginatus, tiger Galeocerdo cuvier, and sliteye Loxodon macrorhinus sharks were the most abundant species (>64% of shark abundances). Multivariate regression trees showed that hard coral cover produced the primary split separating shark assemblages. Four indicator species had consistently higher abundances and contributed to explaining most of the differences in shark assemblages: C. amblyrhynchos, C. albimarginatus, G. cuvier, and whitetip reef Triaenodon obesus sharks. Relative distance along the GBRMP had the greatest influence on shark occurrence and species richness, which increased at both ends of the sampling range (southern and northern sites) relative to intermediate latitudes. Hard coral cover and distance across the shelf were also important predictors of shark distribution. The relative abundance of sharks was significantly higher in non-fished sites, highlighting the conservation value and benefits of the GBRMP zoning. However, our results also showed that hard coral cover had a large effect on the abundance of reef-associated shark species, indicating that coral reef health may be important for the success of marine protected areas. Therefore, understanding shark distribution patterns, species-habitat associations, and the drivers responsible for those patterns is essential for developing sound management and conservation approaches.

  3. Species distribution models of tropical deep-sea snappers.

    PubMed

    Gomez, Céline; Williams, Ashley J; Nicol, Simon J; Mellin, Camille; Loeun, Kim L; Bradshaw, Corey J A

    2015-01-01

    Deep-sea fisheries provide an important source of protein to Pacific Island countries and territories that are highly dependent on fish for food security. However, spatial management of these deep-sea habitats is hindered by insufficient data. We developed species distribution models using spatially limited presence data for the main harvested species in the Western Central Pacific Ocean. We used bathymetric and water temperature data to develop presence-only species distribution models for the commercially exploited deep-sea snappers Etelis Cuvier 1828, Pristipomoides Valenciennes 1830, and Aphareus Cuvier 1830. We evaluated the performance of four different algorithms (CTA, GLM, MARS, and MAXENT) within the BIOMOD framework to obtain an ensemble of predicted distributions. We projected these predictions across the Western Central Pacific Ocean to produce maps of potential deep-sea snapper distributions in 32 countries and territories. Depth was consistently the best predictor of presence for all species groups across all models. Bathymetric slope was consistently the poorest predictor. Temperature at depth was a good predictor of presence for GLM only. Model precision was highest for MAXENT and CTA. There were strong regional patterns in predicted distribution of suitable habitat, with the largest areas of suitable habitat (> 35% of the Exclusive Economic Zone) predicted in seven South Pacific countries and territories (Fiji, Matthew & Hunter, Nauru, New Caledonia, Tonga, Vanuatu and Wallis & Futuna). Predicted habitat also varied among species, with the proportion of predicted habitat highest for Aphareus and lowest for Etelis. Despite data paucity, the relationship between deep-sea snapper presence and their environments was sufficiently strong to predict their distribution across a large area of the Pacific Ocean. Our results therefore provide a strong baseline for designing monitoring programs that balance resource exploitation and conservation planning, and

  4. Quantifying shark distribution patterns and species-habitat associations: implications of marine park zoning.

    PubMed

    Espinoza, Mario; Cappo, Mike; Heupel, Michelle R; Tobin, Andrew J; Simpfendorfer, Colin A

    2014-01-01

    Quantifying shark distribution patterns and species-specific habitat associations in response to geographic and environmental drivers is critical to assessing risk of exposure to fishing, habitat degradation, and the effects of climate change. The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS) along the entire Great Barrier Reef Marine Park (GBRMP) over a ten year period. Overall, 21 species of sharks from five families and two orders were recorded. Grey reef Carcharhinus amblyrhynchos, silvertip C. albimarginatus, tiger Galeocerdo cuvier, and sliteye Loxodon macrorhinus sharks were the most abundant species (>64% of shark abundances). Multivariate regression trees showed that hard coral cover produced the primary split separating shark assemblages. Four indicator species had consistently higher abundances and contributed to explaining most of the differences in shark assemblages: C. amblyrhynchos, C. albimarginatus, G. cuvier, and whitetip reef Triaenodon obesus sharks. Relative distance along the GBRMP had the greatest influence on shark occurrence and species richness, which increased at both ends of the sampling range (southern and northern sites) relative to intermediate latitudes. Hard coral cover and distance across the shelf were also important predictors of shark distribution. The relative abundance of sharks was significantly higher in non-fished sites, highlighting the conservation value and benefits of the GBRMP zoning. However, our results also showed that hard coral cover had a large effect on the abundance of reef-associated shark species, indicating that coral reef health may be important for the success of marine protected areas. Therefore, understanding shark distribution patterns, species-habitat associations, and the drivers responsible for those patterns is essential for developing sound management and conservation approaches. PMID

  5. Hysterothylacium simile n. sp. and H. aduncum (Rudolphi, 1802) (Nematoda: Raphidascarididae) from marine fishes in the Bohai and Yellow Sea, China, with comments on the record of H. paralichthydis (Yamaguti, 1941) from Chinese waters.

    PubMed

    Li, Liang; Zhang, Lu-Ping; Liu, Yuan-Yuan

    2013-01-01

    Hysterothylacium simile n. sp., collected from the Japanese seabass Lateolabrax japonicus (Cuvier) (Perciformes: Lateolabracidae) in the Bohai Sea off China, is described using both light and scanning electron microscopy. The new species differs from its congeners in the presence of narrow lateral alae originating a short distance posterior to the base of the ventrolateral lips, a long intestinal caecum (60.4-79.1% of oesophageal length) and a relatively short ventricular appendix (intestinal caecum to ventricular appendix ratio 1:0.58-0.85), long spicules (2.11-2.99 mm, 4.25-7.83% of body length), the number and arrangement of the caudal papillae (32-36 pairs arranged as follows: 27-31 pairs precloacal, 1 pair paracloacal, and 4-5 pairs postcloacal with the second or third pair double) and the presence of a particular midventral precloacal papilla. Specimens originally identified as Contracaecum paralichthydis Yamaguti, 1941 [now H. paralichthydis (Yamaguti, 1941)] by Xü (1957), collected from the yellow striped flounder Pseudopleuronectes herzensteini (Jordan & Snyder) (Pleuronectiformes: Pleuronectidae) in the Yellow Sea off China, were also re-examined. Their morphology clearly revealed they belong to H. aduncum (Rudolphi, 1802), which is also redescribed based on Xü's material. In addition, the morphological variation of caudal papillae in H. aduncum from P. herzensteini was compared, using scanning electron microscopy, with specimens collected from another three fish hosts, Lophius litulon (Jordan) (Lophiiformes: Lophiidae), Scomberomorus niphonius (Cuvier) (Perciformes: Scombridae) and Cleisthenes herzensteini (Schmidt) (Pleuronectiformes: Pleuronectidae), from the Yellow Sea off China. PMID:23263941

  6. Plectorhinchus caeruleonothus, a new species of sweetlips (Perciformes:
    Haemulidae) from northern Australia and the resurrection of P. unicolor (Macleay, 1883), species previously confused with P. schotaf (Forsskål, 1775).

    PubMed

    Johnson, Jeffrey W; Wilmer, Jessica Worthington

    2015-01-01

    Two distinct haemulid fishes from Australia and the Indo-Australian Archipelago respectively have long been confused with Plectorhinchus schotaf (Forsskål, 1775). Plectorhinchus caeruleonothus sp. nov. is described from 17 specimens collected off western and far northern Australia, between the Monte Bello Islands, Western Australia and Torres Strait, Queensland. It has also been confirmed outside this range by photographs taken at Ningaloo Reef and Exmouth Gulf, Western Australia, and at Claremont Isles and Lizard Island, Queensland. The new species is unique among the genus in having a combination of dorsal-fin rays XII, 18-20, lateral-line scales 56-61, gill rakers 7-9 on the upper limb and 18-20 on the lower limb of the first arch, nostrils minute, and fresh colouration in adults including body uniformly grey, cheek, opercles and posterior margin of the opercular membrane uniformly blue-grey, and rim of orbit and upper edge of maxilla dusky yellow. In contrast to its closest congeners, the juveniles have a distinctive pattern of narrow creamish-white to pale grey stripes on a dark grey to chocolate brown background on the head and body, and oblique dark stripes progressing with growth to spots on the caudal fin. Plectorhinchus unicolor (Macleay, 1883) from Japan to northern Australia is resurrected from the synonomy of P. schotaf and redescribed on the basis of the holotype and 24 non-type specimens. Plectorhinchus unicolor is most similar to P. schotaf, but can be distinguished by fresh colouration, modal dorsal and pectoral-fin ray counts and DNA barcoding. Plectorhinchus schotaf appears to be restricted to the region from southeast Africa to the Arabian Sea, including the Red Sea and Persian Gulf. Plectorhinchus griseus (Cuvier in Cuvier & Valenciennes, 1830) from Indian and Sri Lankan Seas has previously been treated as a junior synonym of P. schotaf, but in accordance with Smith (1962), is here confirmed as a valid species, readily distinguished from the

  7. Trachipleistophora extenrec n. sp. a new microsporidian (fungi: microsporidia) infecting mammals.

    PubMed

    Vávra, Jirí; Horák, Ales; Modrý, David; Lukes, Julius; Koudela, Bretislav

    2006-01-01

    A new microsporidian Trachipleistophora extenrec n. sp. was isolated from a muscle lesion of the streaked tenrec Hemicentetes semispinosus Cuvier, 1798 (Mammalia, Tenrecidae), an insectivore endemic to Madagascar. The spores isolated from the tenrec were infectious to severe combined immunodeficient (SCID) mice by intramuscular injection. Material obtained from muscular lesions in mice was used for the parasite description. All developmental stages of the microsporidian were covered by a dense coat, which during sporogony changed into the sporophorous vesicle wall. Eight, 16, 32, or more spores were formed inside the sporophorous vesicle as the result of the division by plasmotomy and sequential fission of a multinucleate sporogonial plasmodium. Spores were ovoid, 4.7 x 2.8 microm in size, had a large posterior vacuole, and had an isofilar polar tube with 15-16 coils. Although the fine structure and the developmental pattern of the organism were in some respects similar to the genus Vavraia, molecular phylogeny based on the gene sequences of the small subunit rRNA and RNA polymerase subunit II indicated that the organism belongs to the genus Trachipleistophora. The diagnostic characters of the genera Trachipleistophora and Vavraia are discussed as well as the discrepancies between the phylogenies of these two microsporidian genera based on morphology and molecules.

  8. Redescription of Cystidicoloides fischeri based on specimens from piranhas in Brazil, and erection of a new genus (Nematoda: Cystidicolidae).

    PubMed

    Moravec, Frantisek; Santos, Michelle D; Brasil-Sato, Marília C

    2008-08-01

    The cystidicolid nematode Cystidicoloides fischeri (Travassos, Artigas and Pereira, 1928) is redescribed from specimens collected from the stomach of the San Francisco piranha, Pygocentrus piraya (Cuvier), and the white piranha, Serrasalmus brandtii (Lütken) (both Characidae, Characiformes) (new host records), from the Três Marias Reservoir, Upper São Francisco River, Minas Gerais state, Brazil. The morphology of this type species of Cystidicoloides Skinker, 1931, studied with both light and scanning electron microscopy, is characterized by some taxonomically important, previously unreported features, such as the presence of a cephalic cuticular collarette, subdorsal and subventral cephalic spikes, cuticular tooth-like elevations inside the prostom, deirids, area rugosa, and details in the structure of the cephalic end. Heliconema izecksohni Fabio, 1982 is transferred to Cystidicoloides as C. izecksohni (Fabio, 1982) n. comb. Cystidicoloides uniseriata Valovaya and Valter, 1988 is considered a species inquirenda with uncertain generic appurtenance. The presence of subdorsal and subventral cephalic spikes and the collarette are characteristic of Cystidicoloides, comprising only species parasitizing Neotropical fishes. The species from salmonids in the Holarctic, hitherto reported mostly as Cystidicoloides ephemeridarum (Linstow, 1872), belongs to a different, newly erected genus, for which the name Salmonema n. gen. (type species S. ephemeridarum) is now proposed. Cystidicoloides prevosti (Choquette, 1951) is transferred to Salmonema as S. prevosti (Choquette, 1951) n. comb. Sterliadochona ssavini Skryabin, 1948 and Sterliadochona Skryabin, 1948 are considered as species inquirenda and a genus inquirendum, respectively. A key to species of Cystidicoloides is provided. PMID:18576775

  9. The relationship among oceanography, prey fields, and beaked whale foraging habitat in the Tongue of the Ocean.

    PubMed

    Hazen, Elliott L; Nowacek, Douglas P; St Laurent, Louis; Halpin, Patrick N; Moretti, David J

    2011-04-27

    Beaked whales, specifically Blainville's (Mesoplodon densirostris) and Cuvier's (Ziphius cavirostris), are known to feed in the Tongue of the Ocean, Bahamas. These whales can be reliably detected and often localized within the Atlantic Undersea Test and Evaluation Center (AUTEC) acoustic sensor system. The AUTEC range is a regularly spaced bottom mounted hydrophone array covering >350 nm(2) providing a valuable network to record anthropogenic noise and marine mammal vocalizations. Assessments of the potential risks of noise exposure to beaked whales have historically occurred in the absence of information about the physical and biological environments in which these animals are distributed. In the fall of 2008, we used a downward looking 38 kHz SIMRAD EK60 echosounder to measure prey scattering layers concurrent with fine scale turbulence measurements from an autonomous turbulence profiler. Using an 8 km, 4-leaf clover sampling pattern, we completed a total of 7.5 repeat surveys with concurrently measured physical and biological oceanographic parameters, so as to examine the spatiotemporal scales and relationships among turbulence levels, biological scattering layers, and beaked whale foraging activity. We found a strong correlation among increased prey density and ocean vertical structure relative to increased click densities. Understanding the habitats of these whales and their utilization patterns will improve future models of beaked whale habitat as well as allowing more comprehensive assessments of exposure risk to anthropogenic sound.

  10. [Development of the modern biological analogy concept in the 19th century].

    PubMed

    Bäumer, A

    1989-01-01

    At the beginning of the 19th century the term analogy was still synonymous with similarity, as for example in the case of Georges Cuvier. Exact criteria for determining analogy are first found in the work of Etienne Geoffroy Saint-Hilaire. Thereupon the English scientists Sharp MacLeay, William Swainson, John Obadiah Westwood and Edwin Strickland distinguished between analogy as correspondence between certain parts of the organism, i. e. only superficial resemblance, and affinity as an essential similarity in some remarkable aspects of form. Relying on these theories Richard Owen developed his theory of analogy ("a part which has the same function as another") and homology ("the same organ in different animals under every variety of form and function"). The criteria to distinguish between these two terms had to be modified and specified when the theory of evolution was developed by Charles Darwin. In the work of Thomas Henry Huxley, Ernst Haeckel and Carl Gegenbaur the modern biological term of analogy was developed, but at the same time it lost much of its importance and homology as a criterion for natural affinity became the central objective of further biological research. PMID:2534606

  11. Skin lesion-associated pathogens from Octopus vulgaris: first detection of Photobacterium swingsii, Lactococcus garvieae and betanodavirus.

    PubMed

    Fichi, G; Cardeti, G; Perrucci, S; Vanni, A; Cersini, A; Lenzi, C; De Wolf, T; Fronte, B; Guarducci, M; Susini, F

    2015-07-23

    The common octopus Octopus vulgaris Cuvier, 1798 is extremely important in fisheries and is a useful protein source in most Mediterranean countries. Here we investigated pathogens associated with skin lesions in 9 naturally deceased specimens that included both cultured and wild common octopus. Within 30 min after death, each octopus was stored at 4°C and microbiologically examined within 24 h. Bacterial colonies, cultured from swabs taken from the lesions, were examined using taxonomical and biochemical analyses. Vibrio alginolyticus and V. parahaemolyticus were only isolated from cultured animals. A conventional PCR targeting the 16S ribosomal RNA (rRNA) gene and sequencing were performed on 2 bacterial isolates that remained unidentified after taxonomical and biochemical analysis. The sequence results indicated that the bacteria had a 99% identity with Lactococcus garvieae and Photobacterium swingsii. L. garvieae was confirmed using a specific PCR based on the 16S-23S rRNA internal transcribed spacer region, while P. swingsii was confirmed by phylogenetic analyses. Although all animals examined were found to be infected by the protozoan species Aggregata octopiana localised in the intestines, it was also present in skin lesions of 2 of the animals. Betanodavirus was detected in both cultured and wild individuals by cell culture, PCR and electron microscopy. These findings are the first report of L. garvieae and betanodavirus from skin lesions of common octopus and the first identification of P. swingsii both in octopus skin lesions and in marine invertebrates in Italy. PMID:26203886

  12. Parasites of cetaceans stranded on the Pacific coast of Costa Rica.

    PubMed

    Oliveira, J B; Morales, J A; González-Barrientos, R C; Hernández-Gamboa, J; Hernández-Mora, G

    2011-12-15

    Information regarding parasitic fauna of cetaceans from Costa Rica is provided for the first time. A total of 25 stranded dolphins and whales were examined between 2001 and 2009, including striped dolphin (Stenella coeruleoalba) (n=19), pantropical spotted dolphin (S. attenuata) (n=2), spinner dolphin (S. longirostris) (n=1), bottlenose dolphin (Tursiops truncatus) (n=1), dwarf sperm whale (Kogia sima) (n=1) and Cuvier's beaked whale (Ziphius cavirostris) (n=1). Pathological findings associated with the parasites are also presented. In the most representative dolphin species, S. coeruleoalba, the prevalence of parasites was 89.5%; moreover, all examined specimens of S. attenuata, S. longirostris, T. truncatus and Z. cavirostris presented parasites. No parasites were recovered from K. sima. Fourteen helminth taxa were identified, including six species of cestodes (Strobilocephalus triangularis, Tetrabothrius forsteri, Trigonocotyle sp., Phyllobothrium delphini, Monorygma grimaldi, Tetraphyllidea gen. sp. plerocercoid), four digeneans (Nasitrema globicephalae, Brachycladium palliatum, B. pacificum and Oschmarinella albamarina) and four nematodes (Anisakis spp., Halocercus lagenorhynchi, Halocercus sp. and Crassicauda anthonyi). A commensal crustacean, Xenobalanus globicipitis, was also identified. All identified parasites representing new geographic records for the Pacific coast of Central America and new host records are presented. Parasitological information is valuable for conservation of cetaceans in Pacific coast of Costa Rica. PMID:21665367

  13. Tectonic events, sequence stratigraphy and prediction of petroleum play elements in the Cretaceous and Tertiary of the northern Carnarvon Basin, north west shelf, Australia

    SciTech Connect

    Romine, K.K.; Durrant, J.D.

    1996-12-31

    The Carnarvon Basin is one of Australia`s most prolific oil and gas provinces. A recent Paleocene discovery has initiated a shift in exploration interest from traditional Jurassic/Triassic plays to the younger Cretaceous and Tertiary section. To improve play element prediction, a sequence stratigraphic study has been completed, utilizing newly acquired, regional high-resolution seismic data and 80 wells. The occurrence and distribution of the key play elements, reservoir, source and seal, is controlled by the interaction of tectonic subsidence, eustasy and paleogeography, with traps and migration pathways set up and modified by regional tectonic events. For example, a major rifting event commenced in the latest Kimmeridgian-Tithonian that resulted in structuring of older Jurassic sediments and initiation of seafloor spreading in the adjacent Cuvier-Gascoyne Abyssal Plain in the Valanginian. This event was accompanied by a dramatic fall in eustasy that initiated the deposition of high-quality reservoir sandstones of the Tithonian-Valanginian age Barrow Delta. The post-rift phase of thermal cooling and rapid subsidence resulted in transgression, accompanied by deposition of backstepping parasequences of the Mardie Greensand, a potential thief zone and reservoir, and culminated in maximum transgression and deposition of seal and source facies of the Muclerong Shale. The improved sequence stratigraphic framework established in this study provides a predictive tool for the development and assessment of new plays.

  14. Tectonic events, sequence stratigraphy and prediction of petroleum play elements in the Cretaceous and Tertiary of the northern Carnarvon Basin, north west shelf, Australia

    SciTech Connect

    Romine, K.K. ); Durrant, J.D. )

    1996-01-01

    The Carnarvon Basin is one of Australia's most prolific oil and gas provinces. A recent Paleocene discovery has initiated a shift in exploration interest from traditional Jurassic/Triassic plays to the younger Cretaceous and Tertiary section. To improve play element prediction, a sequence stratigraphic study has been completed, utilizing newly acquired, regional high-resolution seismic data and 80 wells. The occurrence and distribution of the key play elements, reservoir, source and seal, is controlled by the interaction of tectonic subsidence, eustasy and paleogeography, with traps and migration pathways set up and modified by regional tectonic events. For example, a major rifting event commenced in the latest Kimmeridgian-Tithonian that resulted in structuring of older Jurassic sediments and initiation of seafloor spreading in the adjacent Cuvier-Gascoyne Abyssal Plain in the Valanginian. This event was accompanied by a dramatic fall in eustasy that initiated the deposition of high-quality reservoir sandstones of the Tithonian-Valanginian age Barrow Delta. The post-rift phase of thermal cooling and rapid subsidence resulted in transgression, accompanied by deposition of backstepping parasequences of the Mardie Greensand, a potential thief zone and reservoir, and culminated in maximum transgression and deposition of seal and source facies of the Muclerong Shale. The improved sequence stratigraphic framework established in this study provides a predictive tool for the development and assessment of new plays.

  15. Spatial variation of deep diving odontocetes' occurrence around a canyon region in the Ligurian Sea as measured with acoustic techniques

    NASA Astrophysics Data System (ADS)

    Giorli, Giacomo; Neuheimer, Anna; Au, Whitlow

    2016-10-01

    Understanding the distribution of animals is of paramount importance for management and conservation, especially for species that are impacted by anthropogenic threats. In the case of marine mammals there has been a growing concern about the impact of human-made noise, in particular for beaked whales and other deep diving odontocetes. Foraging (measured via echolocation clicks at depth) was studied for Cuvier's beaked whale (Ziphius cavirostris), sperm whale (Physeter macrocephalus), long-finned pilot whales (Globicephala melas) and Risso's dolphin (Grampus griseus) using three passive acoustics recorders moored to the bottom of the ocean in a canyon area in the Ligurian Sea between July and December 2011. A Generalized Linear Model was used to test whether foraging was influenced by location and day of the year, including the possibility of interactions between predictors. Contrary to previous studies conducted by visual surveys in this area, all species were detected at all locations, suggesting habitat overlapping. However, significant differences were found in the occurrence of each species at different locations. Beaked and sperm whales foraged significantly more in the northern and western locations, while long-finned pilot whales and Risso's dolphins hunted more in the northern and eastern location.

  16. Recurrent gene loss correlates with the evolution of stomach phenotypes in gnathostome history.

    PubMed

    Castro, L Filipe C; Gonçalves, Odete; Mazan, Sylvie; Tay, Boon-Hui; Venkatesh, Byrappa; Wilson, Jonathan M

    2014-01-22

    The stomach, a hallmark of gnathostome evolution, represents a unique anatomical innovation characterized by the presence of acid- and pepsin-secreting glands. However, the occurrence of these glands in gnathostome species is not universal; in the nineteenth century the French zoologist Cuvier first noted that some teleosts lacked a stomach. Strikingly, Holocephali (chimaeras), dipnoids (lungfish) and monotremes (egg-laying mammals) also lack acid secretion and a gastric cellular phenotype. Here, we test the hypothesis that loss of the gastric phenotype is correlated with the loss of key gastric genes. We investigated species from all the main gnathostome lineages and show the specific contribution of gene loss to the widespread distribution of the agastric condition. We establish that the stomach loss correlates with the persistent and complete absence of the gastric function gene kit--H(+)/K(+)-ATPase (Atp4A and Atp4B) and pepsinogens (Pga, Pgc, Cym)--in the analysed species. We also find that in gastric species the pepsinogen gene complement varies significantly (e.g. two to four in teleosts and tens in some mammals) with multiple events of pseudogenization identified in various lineages. We propose that relaxation of purifying selection in pepsinogen genes and possibly proton pump genes in response to dietary changes led to the numerous independent events of stomach loss in gnathostome history. Significantly, the absence of the gastric genes predicts that reinvention of the stomach in agastric lineages would be highly improbable, in line with Dollo's principle. PMID:24307675

  17. Prey preferences among the community of deep-diving odontocetes from the Bay of Biscay, Northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Spitz, Jérôme; Cherel, Yves; Bertin, Stéphane; Kiszka, Jeremy; Dewez, Alexandre; Ridoux, Vincent

    2011-03-01

    Long-finned pilot whales ( Globicephala melas), Risso's dolphins ( Grampus griseus), melon-headed whales ( Peponocephala electra), Cuvier's beaked whales ( Ziphius cavirostris), Sowerby's beaked whales ( Mesoplodon bidens), northern bottlenose whales ( Hyperoodon ampullatus), sperm whales ( Physeter macrocephalus), dwarf sperm whales ( Kogia sima) and pygmy sperm whales ( Kogia breviceps) make up the large community of deep-diving odontocetes occurring off the Bay of Biscay, northeast Atlantic. The ecology of these toothed cetaceans is poorly documented worldwide. The present study described their prey preferences from stomach content analysis and showed resource partitioning within the assemblage. The majority of the species appeared to be mostly teutophageous. Fish was an important food source only for the Sowerby's beaked whale and, to a lesser extent, for the long-finned pilot whale. In terms of foraging habitats inferred from prey composition, either pelagic oceanic or demersal neritic habitats were exploited by toothed whales in the Bay of Biscay, with only the long-finned pilot whale foraging in the two habitats. Finally, with more than 14,000 identified cephalopods from 39 species, the present study highlighted also the poorly known deep-sea cephalopod community off the Bay of Biscay using top predators as biological samplers.

  18. Recovery potential and conservation options for elasmobranchs.

    PubMed

    Ward-Paige, C A; Keith, D M; Worm, B; Lotze, H K

    2012-04-01

    Many elasmobranchs have experienced strong population declines, which have been largely attributed to the direct and indirect effects of exploitation. Recently, however, live elasmobranchs are being increasingly valued for their role in marine ecosystems, dive tourism and intrinsic worth. Thus, management plans have been implemented to slow and ultimately reverse negative trends, including shark-specific (e.g. anti-finning laws) to ecosystem-based (e.g. no-take marine reserves) strategies. Yet it is unclear how successful these measures are, or will be, given the degree of depletion and slow recovery potential of most elasmobranchs. Here, current understanding of elasmobranch population recoveries is reviewed. The potential and realized extent of population increases, including rates of increase, timelines and drivers are evaluated. Across 40 increasing populations, only 25% were attributed to decreased anthropogenic mortality, while the majority was attributed to predation release. It is also shown that even low exploitation rates (2-6% per year) can halt or reverse positive population trends in six populations currently managed under recovery plans. Management measures that help restore elasmobranch populations include enforcement or near-zero fishing mortality, protection of critical habitats, monitoring and education. These measures are highlighted in a case study from the south-eastern U.S.A., where some evidence of recovery is seen in Pristis pectinata, Galeocerdo cuvier and Sphyrna lewini populations. It is concluded that recovery of elasmobranchs is certainly possible but requires time and a combination of strong and dedicated management actions to be successful.

  19. Inbreeding and reproduction in endangered ungulates: preservation of genetic variation through the Organization of Genetic Resource Banks.

    PubMed

    Roldan, E R S; Gomendio, M; Garde, J J; Espeso, G; Ledda, S; Berlinguer, F; del Olmo, A; Soler, A J; Arregui, L; Crespo, C; González, R

    2006-10-01

    There is a constant increase in the number of species suffering marked reductions in population size. This reduction in size and the lack of genetic flow may lead to a decrease in genetic variability and to matings between close relatives (i.e. inbreeding) with an ensuing reduction in fitness. It is thus important to understand the mechanism underlying the deleterious effects of inbreeding and to develop reproductive biotechnologies that will allow the reduction of inbreeding depression by facilitating gene exchange between populations. The study of three endangered species of gazelles, Cuvier's gazelle (Gazella cuvieri), Mohor gazelle (Gazella dama mhorr) and dorcas gazelle (Gazella dorcas neglecta) has revealed that inbreeding negatively affects several semen parameters (motility, sperm morphology, acrosome integrity). Semen cryopreservation has been achieved in the three species but success varies depending on the diluent employed and the level of inbreeding. Artificial insemination of Mohor gazelles have led to the birth of the first gazelle born using frozen-thawed semen but improvements are needed before this technology can be applied on a routine basis for the genetic management of the populations. Collection of oocytes after ovarian stimulation, followed by in vitro maturation, fertilization and culture has met with some initial success in the Mohor gazelle. These, together with other reproductive technologies, will offer an invaluable help in preserving the maximum of genetic diversity of these and related endangered ungulate species. PMID:16984472

  20. Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems

    PubMed Central

    Lea, James S. E.; Wetherbee, Bradley M.; Queiroz, Nuno; Burnie, Neil; Aming, Choy; Sousa, Lara L.; Mucientes, Gonzalo R.; Humphries, Nicolas E.; Harvey, Guy M.; Sims, David W.; Shivji, Mahmood S.

    2015-01-01

    Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks. PMID:26057337

  1. Spontaneous contractions in elasmobranch vessels in vitro.

    PubMed

    Olson, K R; Forster, M E; Bushnell, P G; Duff, D W

    2000-05-01

    Isolated vessels from four elasmobranchs, yellow stingray (Urolophus jamaicensis), clearnose skate (Raja eglanteria), ghost shark (Hydrolagus novaezelandiae), and spiny dogfish (Squalus acanthias), were examined for the presence of spontaneous contractions (SC). SC were observed in otherwise unstimulated dorsal aortas (DA) from stingray and ghost shark, but not in skate DA. Unstimulated ventral aortas (VA) did not exhibit SC. After treatment of VA with a contractile agonist, SC appeared in stingray and skate but not ghost shark or dogfish. SC in stingray VA were subsequently inhibited by either epinephrine (10(-5) M) or indomethacin (10(-4) M). Agonist contraction also elicited strong SC in ductus Cuvier from stingray, but not from ghost shark or dogfish. SC in dogfish hepatic portal veins (HPV) produced a rhythmical oscillation in tension. The frequency of HPV SC was highest (approximately 1 min(-1)) in intact veins and lower (approximately 3 min(-1)) in vein segments, indicative of a dominant pacemaker in the intact vessel. SC in HPV were depressed during the first 30 min of hypoxia, but there was substantial recovery over an additional 30 min of hypoxia and complete recovery upon return to normoxia. Addition of 80 mM KCl completely inhibited HPV SC and lowered resting tone. These results show that SC are a common feature of elasmobranch vessels and there appears to be a correlation between swimming behavior and the propensity for SC. KCl inhibition of SC and tonus in HPV is highly unusual for vascular smooth muscle. PMID:10766969

  2. Shifting elasmobranch community assemblage at Cocos Island--an isolated marine protected area.

    PubMed

    White, Easton R; Myers, Mark C; Flemming, Joanna Mills; Baum, Julia K

    2015-08-01

    Fishing pressure has increased the extinction risk of many elasmobranch (shark and ray) species. Although many countries have established no-take marine reserves, a paucity of monitoring data means it is still unclear if reserves are effectively protecting these species. We examined data collected by a small group of divers over the past 21 years at one of the world's oldest marine protected areas (MPAs), Cocos Island National Park, Costa Rica. We used mixed effects models to determine trends in relative abundance, or probability of occurrence, of 12 monitored elasmobranch species while accounting for variation among observers and from abiotic factors. Eight of 12 species declined significantly over the past 2 decades. We documented decreases in relative abundance for 6 species, including the iconic scalloped hammerhead shark (Sphyrna lewini) (-45%), whitetip reef shark (Triaenodon obesus) (-77%), mobula ray (Mobula spp.) (-78%), and manta ray (Manta birostris) (-89%), and decreases in the probability of occurrence for 2 other species. Several of these species have small home ranges and should be better protected by an MPA, which underscores the notion that declines of marine megafauna will continue unabated in MPAs unless there is adequate enforcement effort to control fishing. In addition, probability of occurrence at Cocos Island of tiger (Galeocerdo cuvier), Galapagos (Carcharhinus galapagensis), blacktip (Carcharhinus limbatus), and whale (Rhincodon typus) sharks increased significantly. The effectiveness of MPAs cannot be evaluated by examining single species because population responses can vary depending on life history traits and vulnerability to fishing pressure.

  3. Revision of Metahaliotrema Yamaguti, 1953 (Monogenoidea: Dactylogyridae), with new and previously described species from the spotted scat Scatophagus argus (Linnaeus) (Perciformes: Scatophagidae) in Vietnam.

    PubMed

    Kritsky, Delane C; Nguyen, Ha Van; Ha, Ngo Duy; Heckmann, Richard A

    2016-05-01

    An emended diagnosis of Metahaliotrema Yamaguti, 1953 (Monogenoidea: Dactylogyridae) is provided based on specimens of six species collected from the spotted scat Scatophagus argus (Linnaeus) (Scatophagidae) in Vietnam: M. scatophagi Yamaguti, 1953 (type-species); M. cf. yamagutii Mizelle & Price, 1964; M. mizellei Venkatanarasaiah, 1981; M. kulkarnii Venkatanarasaiah, 1981; M. ypsilocleithrum n. sp.; and M. similis n. sp. Methaliotrema filamentosum Venkatanarasaiah, 1981 from the whipfin silver-biddy Gerres filamentosus Cuvier (Gerreidae) is included as the only other valid member of the genus. Metahaliotrema arii Yamaguti, 1953 from an ariid catfish is considered incertae sedis within the Dactylogyridae; and Metahaliotrema srivastavai Singh & Agarwal, 1994 from a bagrid catfish is transferred to Chauhanellus Bychowsky & Nagibina, 1969 as Chauhanellus srivastavai (Singh & Agarwal, 1994) n. comb. Metahaliotrema geminatohamula Pan, Ding & Zhang, 1995 from spotted scat in China is determined to be a junior subjective synonym of M. scatophagi. The two new species and M. scatophagi, M. mizellei, and M. kulkarnii are described or redescribed based on specimens from Vietnam. PMID:27095662

  4. Anatomical transformation in mammals: developmental origin of aberrant cervical anatomy in tree sloths.

    PubMed

    Buchholtz, Emily A; Stepien, Courtney C

    2009-01-01

    Mammalian cervical count has been fixed at seven for more than 200 million years. The rare exceptions to this evolutionary constraint have intrigued anatomists since the time of Cuvier, but the developmental processes that generate them are unknown. Here we evaluate competing hypotheses for the evolutionary origin of cervical variants in Bradypus and Choloepus, tree sloths that have broken the seven cervical vertebrae barrier independently and in opposite directions. Transitional and mediolaterally disjunct anatomy characterizes the cervicothoracic vertebral boundary in each genus, although polarities are reversed. The thoracolumbar, lumbosacral, and sacrocaudal boundaries are also disrupted, and are more extreme in individuals with more extreme cervical counts. Hypotheses of homologous, homeotic, meristic, or associational transformations of traditional vertebral column anatomy are not supported by these data. We identify global homeotic repatterning of abaxial relative to primaxial mesodermal derivatives as the origin of the anomalous cervical counts of tree sloths. This interpretation emphasizes the strong resistance of the "rule of seven" to evolutionary change, as morphological stasis has been maintained primaxially coincident with the generation of a functionally longer (Bradypus) or shorter (Choloepus) neck.

  5. Global assessment of molecularly identified Anisakis Dujardin, 1845 (Nematoda: Anisakidae) in their teleost intermediate hosts.

    PubMed

    Kuhn, Thomas; Hailer, Frank; Palm, Harry W; Klimpel, Sven

    2013-05-01

    Here, we present the ITS ribosomal DNA (rDNA) sequence data on 330 larvae of nematodes of the genus Anisakis Dujardin, 1845 collected from 26 different bony fish species from 21 sampling locations and different climatic zones. New host records are provided for Anisakis simplex (Rudolphi, 1809) sensu stricto (s.s.) and A. pegreffli Campana-Rouget et Biocca, 1955 from Anoplopoma fimbria (Pallas) (Santa Barbara, East Pacific), A. typica (Diesing, 1860) from Caesio cuning (Bloch), Lepturacanthus savala (Cuvier) and Katsuwonus pelamis (Linnaeus) (Indonesia, West Pacific), A. simplex s.s. from Cololabis saira (Brevoort) (Hawaii, Central Pacific), A. simplex C of Nascetti et al. (1986) from Sebastolobus alascanus Bean (Santa Barbara, East Pacific) and A. physeteris Baylis, 1923 from Synaphobranchus kaupii Johnson (Namibia, East Atlantic). Comparison with host records from 60 previous molecular studies of Anisakis species reveals the teleost host range so far recorded for the genus. Perciform (57 species) and gadiform (21) fishes were the most frequently infected orders, followed by pleuronectiforms (15) and scorpaeniforms (15). Most commonly infected fish families were Scombridae (12), Gadidae (10), Carangidae (8) and Clupeidae (7), with Merluccius merluccius (Linnaeus) alone harbouring eight Anisakis species. Different intermediate host compositions implicate differing life cycles for the so far molecularly identified Anisakis sibling species. PMID:23724731

  6. Changing Patterns of Microhabitat Utilization by the Threespot Damselfish, Stegastes planifrons, on Caribbean Reefs

    PubMed Central

    Precht, William F.; Aronson, Richard B.; Moody, Ryan M.; Kaufman, Les

    2010-01-01

    Background The threespot damselfish, Stegastes planifrons (Cuvier), is important in mediating interactions among corals, algae, and herbivores on Caribbean coral reefs. The preferred microhabitat of S. planifrons is thickets of the branching staghorn coral Acropora cervicornis. Within the past few decades, mass mortality of A. cervicornis from white-band disease and other factors has rendered this coral a minor ecological component throughout most of its range. Methodology/Principal Findings Survey data from Jamaica (heavily fished), Florida and the Bahamas (moderately fished), the Cayman Islands (lightly to moderately fished), and Belize (lightly fished) indicate that distributional patterns of S. planifrons are positively correlated with live coral cover and topographic complexity. Our results suggest that species-specific microhabitat preferences and the availability of topographically complex microhabitats are more important than the abundance of predatory fish as proximal controls on S. planifrons distribution and abundance. Conclusions/Significance The loss of the primary microhabitat of S. planifrons—A. cervicornis—has forced a shift in the distribution and recruitment of these damselfish onto remaining high-structured corals, especially the Montastraea annularis species complex, affecting coral mortality and algal dynamics throughout the Caribbean. PMID:20520809

  7. Skin lesion-associated pathogens from Octopus vulgaris: first detection of Photobacterium swingsii, Lactococcus garvieae and betanodavirus.

    PubMed

    Fichi, G; Cardeti, G; Perrucci, S; Vanni, A; Cersini, A; Lenzi, C; De Wolf, T; Fronte, B; Guarducci, M; Susini, F

    2015-07-23

    The common octopus Octopus vulgaris Cuvier, 1798 is extremely important in fisheries and is a useful protein source in most Mediterranean countries. Here we investigated pathogens associated with skin lesions in 9 naturally deceased specimens that included both cultured and wild common octopus. Within 30 min after death, each octopus was stored at 4°C and microbiologically examined within 24 h. Bacterial colonies, cultured from swabs taken from the lesions, were examined using taxonomical and biochemical analyses. Vibrio alginolyticus and V. parahaemolyticus were only isolated from cultured animals. A conventional PCR targeting the 16S ribosomal RNA (rRNA) gene and sequencing were performed on 2 bacterial isolates that remained unidentified after taxonomical and biochemical analysis. The sequence results indicated that the bacteria had a 99% identity with Lactococcus garvieae and Photobacterium swingsii. L. garvieae was confirmed using a specific PCR based on the 16S-23S rRNA internal transcribed spacer region, while P. swingsii was confirmed by phylogenetic analyses. Although all animals examined were found to be infected by the protozoan species Aggregata octopiana localised in the intestines, it was also present in skin lesions of 2 of the animals. Betanodavirus was detected in both cultured and wild individuals by cell culture, PCR and electron microscopy. These findings are the first report of L. garvieae and betanodavirus from skin lesions of common octopus and the first identification of P. swingsii both in octopus skin lesions and in marine invertebrates in Italy.

  8. [THE PROFESSORS OF THE NATIONAL MUSEUM OF NATURAL HISTORY AND THE SOCIETY OF THE FRIENDS OF THE SCIENCES OF WARSAW (1800-1832)].

    PubMed

    Daszkiewicz, Piotr

    2015-01-01

    The National Museum of Natural History played a crucial role in the formation of Polish scientific elites in the 19th century. Many Polish students were attending in Paris natural history, botany, zoology, chemistry and mineralogy courses. The Warsaw Society of Friends of Learning was the largest scientific society and one of the most important scientific institutions in Poland. It had also an impact on the political and cultural life of the country, occupied and deprived of freedom at that time. Amongst its founders and members, could be found listeners to the lectures of Lamarck, Haüy, Vauquelin, Desfontaines, Jussieu. Moreover, seven professors of the National Museum of Natural History were elected foreign members of the Warsaw Society of Friends of Learning: Cuvier, Desfontaines, Haüy, Jussieu, Latreille, Mirbel, Vauquelin. The article analyses this choice and underlines the relationship between these scientists and Warsaw's scientists. The results of this research allow to confirm that the National Museum of Natural History was the most important foreign institution in the 19th century for Polish science, and more specifically natural sciences.

  9. Structure and Dynamics of the Shark Assemblage off Recife, Northeastern Brazil

    PubMed Central

    Afonso, André S.; Andrade, Humber A.; Hazin, Fábio H. V.

    2014-01-01

    Understanding the ecological factors that regulate elasmobranch abundance in nearshore waters is essential to effectively manage coastal ecosystems and promote conservation. However, little is known about elasmobranch populations in the western South Atlantic Ocean. An 8-year, standardized longline and drumline survey conducted in nearshore waters off Recife, northeastern Brazil, allowed us to describe the shark assemblage and to monitor abundance dynamics using zero-inflated generalized additive models. This region is mostly used by several carcharhinids and one ginglymostomid, but sphyrnids are also present. Blacknose sharks, Carcharhinus acronotus, were mostly mature individuals and declined in abundance throughout the survey, contrasting with nurse sharks, Ginglymostoma cirratum, which proliferated possibly due to this species being prohibited from all harvest since 2004 in this region. Tiger sharks, Galeocerdo cuvier, were mostly juveniles smaller than 200 cm and seem to use nearshore waters off Recife between January and September. No long-term trend in tiger shark abundance was discernible. Spatial distribution was similar in true coastal species (i.e. blacknose and nurse sharks) whereas tiger sharks were most abundant at the middle continental shelf. The sea surface temperature, tidal amplitude, wind direction, water turbidity, and pluviosity were all selected to predict shark abundance off Recife. Interspecific variability in abundance dynamics across spatiotemporal and environmental gradients suggest that the ecological processes regulating shark abundance are generally independent between species, which could add complexity to multi-species fisheries management frameworks. Yet, further research is warranted to ascertain trends at population levels in the South Atlantic Ocean. PMID:25010514

  10. Evaluation of genotoxic potential throughout the upper and middle stretches of Adige river basin.

    PubMed

    Kračun-Kolarević, Margareta; Kolarević, Stoimir; Jovanović, Jovana; Marković, Vanja; Ilić, Marija; Simonović, Predrag; Simić, Vladica; Gačić, Zoran; Diamantini, Elena; Stella, Elisa; Petrović, Mira; Majone, Bruno; Bellin, Alberto; Paunović, Momir; Vuković-Gačić, Branka

    2016-11-15

    In this study a comprehensive genotoxicological survey throughout the upper and middle stretches of Adige river basin is presented. The study was carried out at 7 sites located along the Adige main course and one the most significant tributaries, the Noce creek, both presenting different levels of pollution pressure. To give an insight into the nature of the genotoxic activity we employed the battery of prokaryotic and eukaryotic assays. Mutagenicity in water samples was evaluated by SOS/umuC test in Salmonella typhimurium TA1535/pSK1002. The level of DNA damage as a biomarker of exposure (comet assay) and biomarker of effect (micronucleus assay) and the level of oxidative stress as well (Fpg - modified comet assay) were studied in blood cells of Salmo cenerinus Nardo, 1847 and Salmo marmoratus Cuvier, 1829. Within the applied bioassays, comet assay showed the highest potential for discriminating the sampling sites which are under lesser extent of pressure (sampling sites 1-Barnes at Bresimo and 4-Noce downstream S. Giustina) from the sites under high pressure (sampling sites 5-Noce at Mezzolombardo and 6/7-Adige upstream and downstream municipality of Trento). Significant correlation between the standard and Fpg - modified comet assay indicated that oxidative stress could be a major contributor to observed DNA damage in collected specimens. PMID:27450952

  11. Three Anisakis spp. isolated from toothed whales stranded along the eastern Adriatic Sea coast.

    PubMed

    Blažeković, Kristina; Pleić, Ivana Lepen; Đuras, Martina; Gomerčić, Tomislav; Mladineo, Ivona

    2015-01-01

    Knowledge concerning cetacean ecology in the Mediterranean is limited but important for sustainable planning and enforcement of appropriate conservation measures. Any information that might help to elucidate their ecology is essential. We explored the population and genetic structures of Anisakis spp. nematodes isolated from four toothed whale species - bottlenose dolphins (Tursiops truncatus), striped dolphins (Stenella coeruleoalba), Risso's dolphins (Grampus griseus) and Cuvier's beaked whales (Ziphius cavirostris) - stranded along the eastern Adriatic Sea coast (1990-2012) to reveal more information on host ecological patterns. Lower parasite prevalence was observed in resident dolphin species compared with occasionally occurring species, as well as in young compared with adult dolphins, indicating different feeding habits related to age. No unequivocal relationship between the biological traits of a host (age, body length, body mass and blubber depth) and Anisakis population parameters was observed. Phylogenetic analysis revealed a new geographical record of Anisakis simplex sensu stricto (1.96%) and Anisakis physeteris (1.31%) in the Adriatic Sea in addition to resident Anisakis pegreffii (96.73%). In an assessment of the Adriatic Sea and oceans worldwide, the genetic structure of Anisakis revealed that A. pegreffii populations do not differ among various final host species but do differ with respect to geographical location in contrast to previously accepted Anisakis panmixia.

  12. Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems.

    PubMed

    Lea, James S E; Wetherbee, Bradley M; Queiroz, Nuno; Burnie, Neil; Aming, Choy; Sousa, Lara L; Mucientes, Gonzalo R; Humphries, Nicolas E; Harvey, Guy M; Sims, David W; Shivji, Mahmood S

    2015-01-01

    Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.

  13. Revision of Metahaliotrema Yamaguti, 1953 (Monogenoidea: Dactylogyridae), with new and previously described species from the spotted scat Scatophagus argus (Linnaeus) (Perciformes: Scatophagidae) in Vietnam.

    PubMed

    Kritsky, Delane C; Nguyen, Ha Van; Ha, Ngo Duy; Heckmann, Richard A

    2016-05-01

    An emended diagnosis of Metahaliotrema Yamaguti, 1953 (Monogenoidea: Dactylogyridae) is provided based on specimens of six species collected from the spotted scat Scatophagus argus (Linnaeus) (Scatophagidae) in Vietnam: M. scatophagi Yamaguti, 1953 (type-species); M. cf. yamagutii Mizelle & Price, 1964; M. mizellei Venkatanarasaiah, 1981; M. kulkarnii Venkatanarasaiah, 1981; M. ypsilocleithrum n. sp.; and M. similis n. sp. Methaliotrema filamentosum Venkatanarasaiah, 1981 from the whipfin silver-biddy Gerres filamentosus Cuvier (Gerreidae) is included as the only other valid member of the genus. Metahaliotrema arii Yamaguti, 1953 from an ariid catfish is considered incertae sedis within the Dactylogyridae; and Metahaliotrema srivastavai Singh & Agarwal, 1994 from a bagrid catfish is transferred to Chauhanellus Bychowsky & Nagibina, 1969 as Chauhanellus srivastavai (Singh & Agarwal, 1994) n. comb. Metahaliotrema geminatohamula Pan, Ding & Zhang, 1995 from spotted scat in China is determined to be a junior subjective synonym of M. scatophagi. The two new species and M. scatophagi, M. mizellei, and M. kulkarnii are described or redescribed based on specimens from Vietnam.

  14. Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems

    NASA Astrophysics Data System (ADS)

    Lea, James S. E.; Wetherbee, Bradley M.; Queiroz, Nuno; Burnie, Neil; Aming, Choy; Sousa, Lara L.; Mucientes, Gonzalo R.; Humphries, Nicolas E.; Harvey, Guy M.; Sims, David W.; Shivji, Mahmood S.

    2015-06-01

    Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.

  15. Structure and dynamics of the shark assemblage off Recife, Northeastern Brazil.

    PubMed

    Afonso, André S; Andrade, Humber A; Hazin, Fábio H V

    2014-01-01

    Understanding the ecological factors that regulate elasmobranch abundance in nearshore waters is essential to effectively manage coastal ecosystems and promote conservation. However, little is known about elasmobranch populations in the western South Atlantic Ocean. An 8-year, standardized longline and drumline survey conducted in nearshore waters off Recife, northeastern Brazil, allowed us to describe the shark assemblage and to monitor abundance dynamics using zero-inflated generalized additive models. This region is mostly used by several carcharhinids and one ginglymostomid, but sphyrnids are also present. Blacknose sharks, Carcharhinus acronotus, were mostly mature individuals and declined in abundance throughout the survey, contrasting with nurse sharks, Ginglymostoma cirratum, which proliferated possibly due to this species being prohibited from all harvest since 2004 in this region. Tiger sharks, Galeocerdo cuvier, were mostly juveniles smaller than 200 cm and seem to use nearshore waters off Recife between January and September. No long-term trend in tiger shark abundance was discernible. Spatial distribution was similar in true coastal species (i.e. blacknose and nurse sharks) whereas tiger sharks were most abundant at the middle continental shelf. The sea surface temperature, tidal amplitude, wind direction, water turbidity, and pluviosity were all selected to predict shark abundance off Recife. Interspecific variability in abundance dynamics across spatiotemporal and environmental gradients suggest that the ecological processes regulating shark abundance are generally independent between species, which could add complexity to multi-species fisheries management frameworks. Yet, further research is warranted to ascertain trends at population levels in the South Atlantic Ocean.

  16. Mercury accumulation in sharks from the coastal waters of southwest Florida.

    PubMed

    Rumbold, Darren; Wasno, Robert; Hammerschlag, Neil; Volety, Aswani

    2014-10-01

    As large long-lived predators, sharks are particularly vulnerable to exposure to methylmercury biomagnified through the marine food web. Accordingly, nonlethal means were used to collect tissues for determining mercury (Hg) concentrations and stable isotopes of carbon (δ(13)C) and nitrogen (δ(15)N) from a total of 69 sharks, comprising 7 species, caught off Southwest Florida from May 2010 through June 2013. Species included blacknose (Carcharhinus acronotus), blacktip (C. limbatus), bull (C. leucas), great hammerhead (Sphyrna mokarran), lemon (Negaprion brevirostris), sharpnose (Rhizoprionodon terraenovae), and tiger sharks (Galeocerdo cuvier). The sharks contained Hg concentrations in their muscle tissues ranging from 0.19 mg/kg (wet-weight basis) in a tiger shark to 4.52 mg/kg in a blacktip shark. Individual differences in total length and δ(13)C explained much of the intraspecific variation in Hg concentrations in blacknose, blacktip, and sharpnose sharks, but similar patterns were not evident for Hg and δ(15)N. Interspecific differences in Hg concentration were evident with greater concentrations in slower-growing, mature blacktip sharks and lower concentrations in faster-growing, young tiger sharks than other species. These results are consistent with previous studies reporting age-dependent growth rate can be an important determinant of intraspecific and interspecific patterns in Hg accumulation. The Hg concentrations observed in these sharks, in particular the blacktip shark, also suggested that Hg may pose a threat to shark health and fitness.

  17. Heredity, development and evolution: the unmodern synthesis of E.S. Russell.

    PubMed

    Esposito, Maurizio

    2013-09-01

    In 1930, while R.A. Fisher, J.B.S. Haldane, E.B. Ford and S.G. Wright were laying the foundations of what a decade later J.S. Huxley dubbed "Modern Synthesis", E.S. Russell published a groundbreaking work, The Interpretation of Development and Heredity. In this book Russell not only condemned Mendelian genetics and neo-Darwinism, but also proposed an alternative synthesis unifying heredity, development, and evolution. The book did not represent the work of a mind operating in isolation. Rather, it was a synthetic work connecting ideas and doctrines of many influential scientists working in Europe and the USA. Through the analysis of archival documents and rarely or never mentioned sources, this article provides an unconventional picture of Russell's theoretical biology. It will be shown that Russell was an international celebrity; he was at the centre of a large network of scholars who shared his ideas and insights. He was one of several biologists arguing for a different synthesis; a synthesis perhaps less visible, less institutionalised, and less 'modern', nevertheless with its influential advocates and international support. Finally, this study shows that Russell's synthesis was not rooted in the classic pantheon of towering figures in the history of biology, i.e. Darwin, Wallace, and Mendel, but was based on the teachings of Kant, Goethe, Cuvier, von Baer, and Müller. PMID:23408008

  18. Body condition predicts energy stores in apex predatory sharks

    PubMed Central

    Gallagher, Austin J.; Wagner, Dominique N.; Irschick, Duncan J.; Hammerschlag, Neil

    2014-01-01

    Animal condition typically reflects the accumulation of energy stores (e.g. fatty acids), which can influence an individual's decision to undertake challenging life-history events, such as migration and reproduction. Accordingly, researchers often use measures of animal body size and/or weight as an index of condition. However, values of condition, such as fatty acid levels, may not always reflect the physiological state of animals accurately. While the relationships between condition indices and energy stores have been explored in some species (e.g. birds), they have yet to be examined in top predatory fishes, which often undertake extensive and energetically expensive migrations. We used an apex predatory shark (Galeocerdo cuvier, the tiger shark) as a model species to evaluate the relationship between triglycerides (energy metabolite) and a metric of overall body condition. We captured, blood sampled, measured and released 28 sharks (size range 125–303 cm pre-caudal length). In the laboratory, we assayed each plasma sample for triglyceride values. We detected a positive and significant relationship between condition and triglyceride values (P < 0.02). This result may have conservation implications if the largest and highest-condition sharks are exploited in fisheries, because these individuals are likely to have the highest potential for successful reproduction. Our results suggest that researchers may use either plasma triglyceride values or an appropriate measure of body condition for assessing health in large sharks. PMID:27293643

  19. Mercury accumulation in sharks from the coastal waters of southwest Florida.

    PubMed

    Rumbold, Darren; Wasno, Robert; Hammerschlag, Neil; Volety, Aswani

    2014-10-01

    As large long-lived predators, sharks are particularly vulnerable to exposure to methylmercury biomagnified through the marine food web. Accordingly, nonlethal means were used to collect tissues for determining mercury (Hg) concentrations and stable isotopes of carbon (δ(13)C) and nitrogen (δ(15)N) from a total of 69 sharks, comprising 7 species, caught off Southwest Florida from May 2010 through June 2013. Species included blacknose (Carcharhinus acronotus), blacktip (C. limbatus), bull (C. leucas), great hammerhead (Sphyrna mokarran), lemon (Negaprion brevirostris), sharpnose (Rhizoprionodon terraenovae), and tiger sharks (Galeocerdo cuvier). The sharks contained Hg concentrations in their muscle tissues ranging from 0.19 mg/kg (wet-weight basis) in a tiger shark to 4.52 mg/kg in a blacktip shark. Individual differences in total length and δ(13)C explained much of the intraspecific variation in Hg concentrations in blacknose, blacktip, and sharpnose sharks, but similar patterns were not evident for Hg and δ(15)N. Interspecific differences in Hg concentration were evident with greater concentrations in slower-growing, mature blacktip sharks and lower concentrations in faster-growing, young tiger sharks than other species. These results are consistent with previous studies reporting age-dependent growth rate can be an important determinant of intraspecific and interspecific patterns in Hg accumulation. The Hg concentrations observed in these sharks, in particular the blacktip shark, also suggested that Hg may pose a threat to shark health and fitness. PMID:24942905

  20. Structure and dynamics of the shark assemblage off Recife, Northeastern Brazil.

    PubMed

    Afonso, André S; Andrade, Humber A; Hazin, Fábio H V

    2014-01-01

    Understanding the ecological factors that regulate elasmobranch abundance in nearshore waters is essential to effectively manage coastal ecosystems and promote conservation. However, little is known about elasmobranch populations in the western South Atlantic Ocean. An 8-year, standardized longline and drumline survey conducted in nearshore waters off Recife, northeastern Brazil, allowed us to describe the shark assemblage and to monitor abundance dynamics using zero-inflated generalized additive models. This region is mostly used by several carcharhinids and one ginglymostomid, but sphyrnids are also present. Blacknose sharks, Carcharhinus acronotus, were mostly mature individuals and declined in abundance throughout the survey, contrasting with nurse sharks, Ginglymostoma cirratum, which proliferated possibly due to this species being prohibited from all harvest since 2004 in this region. Tiger sharks, Galeocerdo cuvier, were mostly juveniles smaller than 200 cm and seem to use nearshore waters off Recife between January and September. No long-term trend in tiger shark abundance was discernible. Spatial distribution was similar in true coastal species (i.e. blacknose and nurse sharks) whereas tiger sharks were most abundant at the middle continental shelf. The sea surface temperature, tidal amplitude, wind direction, water turbidity, and pluviosity were all selected to predict shark abundance off Recife. Interspecific variability in abundance dynamics across spatiotemporal and environmental gradients suggest that the ecological processes regulating shark abundance are generally independent between species, which could add complexity to multi-species fisheries management frameworks. Yet, further research is warranted to ascertain trends at population levels in the South Atlantic Ocean. PMID:25010514

  1. Differences in foraging activity of deep sea diving odontocetes in the Ligurian Sea as determined by passive acoustic recorders

    NASA Astrophysics Data System (ADS)

    Giorli, Giacomo; Au, Whitlow W. L.; Neuheimer, Anna

    2016-01-01

    Characterizing the trophic roles of deep-diving odontocete species and how they vary in space and time is challenged by our ability to observe foraging behavior. Though sampling methods are limited, foraging activity of deep-diving odontocetes can be monitored by recording their biosonar emissions. Daily occurrence of echolocation clicks was monitored acoustically for five months (July-December 2011) in the Ligurian Sea (Mediterranean Sea) using five passive acoustic recorders. Detected odontocetes included Cuvier's beaked whales (Zipuhius cavirostris), sperm whales (Physeter macrocephalus), Risso's dolphins (Grampus griseus), and long-finned pilot whales (Globicephala melas). The results indicated that the foraging strategies varied significantly over time, with sperm whales switching to nocturnal foraging in late September whereas Risso's dolphins and pilot whales foraged mainly at night throughout the sampling period. In the study area, winter nights are about five hours longer than summer nights and an analysis showed that pilot whales and Risso's dolphins adjusted their foraging activity with the length of the night, foraging longer during the longer winter nights. This is the first study to show that marine mammals exhibit diurnal foraging patterns closely correlated to sunrise and sunset.

  2. Predator-guided sampling reveals biotic structure in the bathypelagic.

    PubMed

    Benoit-Bird, Kelly J; Southall, Brandon L; Moline, Mark A

    2016-02-24

    We targeted a habitat used differentially by deep-diving, air-breathing predators to empirically sample their prey's distributions off southern California. Fine-scale measurements of the spatial variability of potential prey animals from the surface to 1,200 m were obtained using conventional fisheries echosounders aboard a surface ship and uniquely integrated into a deep-diving autonomous vehicle. Significant spatial variability in the size, composition, total biomass, and spatial organization of biota was evident over all spatial scales examined and was consistent with the general distribution patterns of foraging Cuvier's beaked whales (Ziphius cavirostris) observed in separate studies. Striking differences found in prey characteristics between regions at depth, however, did not reflect differences observed in surface layers. These differences in deep pelagic structure horizontally and relative to surface structure, absent clear physical differences, change our long-held views of this habitat as uniform. The revelation that animals deep in the water column are so spatially heterogeneous at scales from 10 m to 50 km critically affects our understanding of the processes driving predator-prey interactions, energy transfer, biogeochemical cycling, and other ecological processes in the deep sea, and the connections between the productive surface mixed layer and the deep-water column. PMID:26888030

  3. Amino acids, fatty acids and sterols profile of some marine organisms from Portuguese waters.

    PubMed

    Pereira, David M; Valentão, Patrícia; Teixeira, Natércia; Andrade, Paula B

    2013-12-01

    Marine organisms have been increasingly regarded as good sources of new drugs for human therapeutics and also as nutrients for human diet. The amino acids, fatty acids and sterols profiles of the widely consumed echinoderms Paracentrotus lividus Lamarck (sea urchin), Holothuria forskali Chiaje (sea cucumber), the gastropod molluscs Aplysia fasciata Poiret and Aplysia punctata Cuvier (sea hares), from Portuguese waters, were established by GC-MS analysis. Overall, 10 amino acids, 14 fatty acids and 4 sterols were determined. In general, all species presented the 10 amino acids identified, with the exceptions of H. forskali, in which no glycine, proline, trans-4-hydroxy-proline or phenylalanine were found, and of A. fasciata which did not contain proline. Unsaturated fatty acids were predominant compounds, with those from the ω-6 series, being in higher amounts than their ω-3 homologues, and cholesterol being the main sterol. The amino acids, fatty acids and sterols qualitative and quantitative composition of A. fasciata, A. punctata and H. forskali is reported here for the first time.

  4. Structure, composition, and mechanical properties of shark teeth.

    PubMed

    Enax, Joachim; Prymak, Oleg; Raabe, Dierk; Epple, Matthias

    2012-06-01

    The teeth of two different shark species (Isurus oxyrinchus and Galeocerdo cuvier) and a geological fluoroapatite single crystal were structurally and chemically characterized. In contrast to dentin, enameloid showed sharp diffraction peaks which indicated a high crystallinity of the enameloid. The lattice parameters of enameloid were close to those of the geological fluoroapatite single crystal. The inorganic part of shark teeth consisted of fluoroapatite with a fluoride content in the enameloid of 3.1 wt.%, i.e., close to the fluoride content of the geological fluoroapatite single crystal (3.64 wt.%). Scanning electron micrographs showed that the crystals in enameloid were highly ordered with a special topological orientation (perpendicular towards the outside surface and parallel towards the center). By thermogravimetry, water, organic matrix, and biomineral in dentin and enameloid of both shark species were determined. Dentin had a higher content of water, organic matrix, and carbonate than enameloid but contained less fluoride. Nanoindentation and Vicker's microhardness tests showed that the enameloid of the shark teeth was approximately six times harder than the dentin. The hardness of shark teeth and human teeth was comparable, both for dentin and enamel/enameloid. In contrast, the geological fluoroapatite single crystal was much harder than both kinds of teeth due to the absence of an organic matrix. In summary, the different biological functions of the shark teeth ("tearing" for Isurus and "cutting" for Galeocerdo) are controlled by the different geometry and not by the chemical or crystallographic composition.

  5. Four species of digeneans, including Allocreadium patagonicum sp. n. (Allocreadiidae), from freshwater fishes of Patagonia, Argentina.

    PubMed

    Shimazu, T; Urawa, S; Coria, C O

    2000-01-01

    Four species of adult digeneans are reported from freshwater fishes of two lakes in Neuquén, Patagonia, Argentina. Allocreadium patagonicum sp. n. (Allocreadiidae) is described from the intestine of Percichthys colhuapiensis MacDonagh and Percichthys trucha (Cuvier et Valenciennes) (Percichthyidae) from Lago Aluminé. Three species redescribed are: Acanthostomoides apophalliformis Szidat, 1956 (Acanthostomidae) from the intestine of P. colhuapiensis and P. trucha from Lago Aluminé and of Salmo trutta (Linnaeus) (Salmonidae) from Lago Huechulafquén; Deropegus patagonicus (Szidat, 1956) comb. n. (= Genarches patagonicus Szidat, 1956) (Derogenidae) from the stomach of P. colhuapiensis, P. trucha, Oncorhynchus mykiss (Walbaum) (Salmonidae) and Salvelinus fontinalis (Mitchill) (Salmonidae) from Lago Aluminé and of S. trutta from Lago Huechulafquén; and Austrocreadium papilliferum Szidat, 1956 from the intestine of P. trucha from Lago Aluminé. The genus Polylekithum Arnold, 1934 is considered a synonym of the genus Allocreadium Looss, 1900. The genus Austrocreadium Szidat, 1956 is removed to the family Homalometridae.

  6. Infestation of Lernaeenicus seeri (Copepoda: Pennellidae) and Hirudinella ventricosa (Digenea: Hirudinellidae) on wahoo Acanthocybium solandri collected from Parangipettai, southeast coast of India.

    PubMed

    Raja, K; Venmathi Maran, B A; Gopalakrishnan, A; Saravanakumar, A; Vijayakumar, R; Sinduja, K

    2014-09-01

    A commercially important fish, wahoo Acanthocybium solandri (Cuvier, 1832) (Scombridae), was collected to study the infestation of parasites from Parangipettai landing center, Tamil Nadu, southeast coast of India for a period of one year from January to December 2011. A total of 644 fish were captured and screened for parasites. Off 644 fish, 270 were infested by a parasitic copepod Lernaeenicus seeri Kirtisinghe, 1934 (Siphonostomatoida: Pennellidae) on the body surface. It is a mesoparasite, since the head and neck are inserted and attached to the muscle by making a wound/hole on the body and the rest of the parasite body with the egg sacs hanging outside. Prevalence was recorded as 42.29% with mean and maximum intensity at 3.22 and 33, respectively. Seasonal study showed that the prevalence was highest (62.82 %) during postmonsoon. Simultaneously, some of the fish (n = 144) were internally observed for the presence of parasites and we found that 101 fish were infested with an endoparasite digenean Hirudinella ventricosa (Pallas, 1774) (Hirudinellidae) in the stomach. Prevalence was recorded as 70.9%, and mean intensity of 1.62 and maximum intensity of 3 were also noted. The overall percentage of both copepod and digenean infestation were recorded as 60.42%. The infestation was high in postmonsoon season for both parasites. This is the first record of L. seeri from Indian waters and the second record of occurrence worldwide. Significant interactions were observed between season and infestation of both parasites (P<0.05).

  7. Neural and muscular control functions of the gut in odontocetes: morphologic evidence in beaked whales and beluga whales.

    PubMed

    Pfeiffer, C J

    1993-01-01

    The present data provide some new and unique, gastrointestinal morphologic findings in two species of toothed whales, the Cuvier's beaked whale (Ziphius cavirostris) and the beluga or white whale (Delphinapterus leucas), which are discussed relative to their atypical feeding behavior and alimentary tract functions. Specifically, the findings show myenteric neural modifications and muscularis externa structural specializations which may support voluntary and involuntary fore- and hindgut behavior. Histologic evidence of intercalation-like striations in the gastric and colonic musculature was discovered, as well as an unusual massive size of the colonic myenteric plexuses. These observations, which are not evident in terrestrial mammalian gastrointestinal tracts, may help explain the unusual upper gastrointestinal tract motility such as ingestion-by-sucking in the absence of prehensile teeth and processing of ingesta in a multi-compartmentalized pyloric stomach. Further, the hindgut modifications may help explain the animal's acute, rectal discharge escape mechanism, likened to squid inking, which seems to be an evolved function of some cetaceans.

  8. The Relationship among Oceanography, Prey Fields, and Beaked Whale Foraging Habitat in the Tongue of the Ocean

    PubMed Central

    Hazen, Elliott L.; Nowacek, Douglas P.; St. Laurent, Louis; Halpin, Patrick N.; Moretti, David J.

    2011-01-01

    Beaked whales, specifically Blainville's (Mesoplodon densirostris) and Cuvier's (Ziphius cavirostris), are known to feed in the Tongue of the Ocean, Bahamas. These whales can be reliably detected and often localized within the Atlantic Undersea Test and Evaluation Center (AUTEC) acoustic sensor system. The AUTEC range is a regularly spaced bottom mounted hydrophone array covering >350 nm2 providing a valuable network to record anthropogenic noise and marine mammal vocalizations. Assessments of the potential risks of noise exposure to beaked whales have historically occurred in the absence of information about the physical and biological environments in which these animals are distributed. In the fall of 2008, we used a downward looking 38 kHz SIMRAD EK60 echosounder to measure prey scattering layers concurrent with fine scale turbulence measurements from an autonomous turbulence profiler. Using an 8 km, 4-leaf clover sampling pattern, we completed a total of 7.5 repeat surveys with concurrently measured physical and biological oceanographic parameters, so as to examine the spatiotemporal scales and relationships among turbulence levels, biological scattering layers, and beaked whale foraging activity. We found a strong correlation among increased prey density and ocean vertical structure relative to increased click densities. Understanding the habitats of these whales and their utilization patterns will improve future models of beaked whale habitat as well as allowing more comprehensive assessments of exposure risk to anthropogenic sound. PMID:21556355

  9. Passive acoustic monitoring using a towed hydrophone array results in identification of a previously unknown beaked whale habitat.

    PubMed

    Yack, Tina M; Barlow, Jay; Calambokidis, John; Southall, Brandon; Coates, Shannon

    2013-09-01

    Beaked whales are diverse and species rich taxa. They spend the vast majority of their time submerged, regularly diving to depths of hundreds to thousands of meters, typically occur in small groups, and behave inconspicuously at the surface. These factors make them extremely difficult to detect using standard visual survey methods. However, recent advancements in acoustic detection capabilities have made passive acoustic monitoring (PAM) a viable alternative. Beaked whales can be discriminated from other odontocetes by the unique characteristics of their echolocation clicks. In 2009 and 2010, PAM methods using towed hydrophone arrays were tested. These methods proved highly effective for real-time detection of beaked whales in the Southern California Bight (SCB) and were subsequently implemented in 2011 to successfully detect and track beaked whales during the ongoing Southern California Behavioral Response Study. The three year field effort has resulted in (1) the successful classification and tracking of Cuvier's (Ziphius cavirostris), Baird's (Berardius bairdii), and unidentified Mesoplodon beaked whale species and (2) the identification of areas of previously unknown beaked whale habitat use. Identification of habitat use areas will contribute to a better understanding of the complex relationship between beaked whale distribution, occurrence, and preferred habitat characteristics on a relatively small spatial scale. These findings will also provide information that can be used to promote more effective management and conservation of beaked whales in the SCB, a heavily used Naval operation and training region.

  10. Tetraphyllidean plerocercoids from Western Mediterranean cetaceans and other marine mammals around the world: a comprehensive morphological analysis.

    PubMed

    Agustí, Celia; Aznar, Francisco Javier; Raga, Juan Antonio

    2005-02-01

    Tetraphyllidean plerocercoids have occasionally been reported in marine mammals, but they have rarely been described in detail, and the ecological significance of these infections is unclear. We described plerocercoids collected from the mucosa of the terminal colon and rectum, the anal crypts, and the hepatopancreatic ducts of 7 striped dolphins Stenella coeruleoalba, 1 Cuvier's beaked whale Ziphius cavirostris, and 3 Risso's dolphins Grampus griseus from the Spanish Mediterranean. We also examined undescribed plerocercoids from 3 cetacean species from the Atlantic and the Pacific. All plerocercoids had a lanceolate body, and a scolex with an apical sucker and 4 sessile monolocular bothridia. The bothridia had free posterior edges and an accessory sucker at their anterior end. Under light microscopy, the bothridia of some Mediterranean specimens looked bilocular without accessory suckers, but a true accessory sucker was observed in histological sections. A principal component analysis revealed 2 stable clusters of specimens along the first principal component regardless of host species. These "large" and "small" morphotypes are thought to represent early migratory stages of Phyllobothrium delphini and Monorygma grimaldii. The similarity in scolex morphology, the observation of plerocercoids buried in intestinal regions close to the sites where M. grimaldii and P. delphini occur, and the coexistence of all larval forms in the same individual hosts would support this hypothesis. Future molecular analysis may confirm it.

  11. Parasites of cetaceans stranded on the Pacific coast of Costa Rica.

    PubMed

    Oliveira, J B; Morales, J A; González-Barrientos, R C; Hernández-Gamboa, J; Hernández-Mora, G

    2011-12-15

    Information regarding parasitic fauna of cetaceans from Costa Rica is provided for the first time. A total of 25 stranded dolphins and whales were examined between 2001 and 2009, including striped dolphin (Stenella coeruleoalba) (n=19), pantropical spotted dolphin (S. attenuata) (n=2), spinner dolphin (S. longirostris) (n=1), bottlenose dolphin (Tursiops truncatus) (n=1), dwarf sperm whale (Kogia sima) (n=1) and Cuvier's beaked whale (Ziphius cavirostris) (n=1). Pathological findings associated with the parasites are also presented. In the most representative dolphin species, S. coeruleoalba, the prevalence of parasites was 89.5%; moreover, all examined specimens of S. attenuata, S. longirostris, T. truncatus and Z. cavirostris presented parasites. No parasites were recovered from K. sima. Fourteen helminth taxa were identified, including six species of cestodes (Strobilocephalus triangularis, Tetrabothrius forsteri, Trigonocotyle sp., Phyllobothrium delphini, Monorygma grimaldi, Tetraphyllidea gen. sp. plerocercoid), four digeneans (Nasitrema globicephalae, Brachycladium palliatum, B. pacificum and Oschmarinella albamarina) and four nematodes (Anisakis spp., Halocercus lagenorhynchi, Halocercus sp. and Crassicauda anthonyi). A commensal crustacean, Xenobalanus globicipitis, was also identified. All identified parasites representing new geographic records for the Pacific coast of Central America and new host records are presented. Parasitological information is valuable for conservation of cetaceans in Pacific coast of Costa Rica.

  12. Predator-guided sampling reveals biotic structure in the bathypelagic.

    PubMed

    Benoit-Bird, Kelly J; Southall, Brandon L; Moline, Mark A

    2016-02-24

    We targeted a habitat used differentially by deep-diving, air-breathing predators to empirically sample their prey's distributions off southern California. Fine-scale measurements of the spatial variability of potential prey animals from the surface to 1,200 m were obtained using conventional fisheries echosounders aboard a surface ship and uniquely integrated into a deep-diving autonomous vehicle. Significant spatial variability in the size, composition, total biomass, and spatial organization of biota was evident over all spatial scales examined and was consistent with the general distribution patterns of foraging Cuvier's beaked whales (Ziphius cavirostris) observed in separate studies. Striking differences found in prey characteristics between regions at depth, however, did not reflect differences observed in surface layers. These differences in deep pelagic structure horizontally and relative to surface structure, absent clear physical differences, change our long-held views of this habitat as uniform. The revelation that animals deep in the water column are so spatially heterogeneous at scales from 10 m to 50 km critically affects our understanding of the processes driving predator-prey interactions, energy transfer, biogeochemical cycling, and other ecological processes in the deep sea, and the connections between the productive surface mixed layer and the deep-water column.

  13. The artisanal fishery of Cynoscion guatucupa in Argentina: Exploring the possible causes of the collapse in Bahía Blanca estuary

    NASA Astrophysics Data System (ADS)

    Lopez Cazorla, Andrea; Molina, Juan Manuel; Ruarte, Claudio

    2014-04-01

    Cynoscion guatucupa Cuvier 1829 is a migratory pelagic fish species, which has a wide geographical distribution. It is the most important fishing resource for local communities in Bahía Blanca estuary and has been captured by artisanal fishermen since the 1900s. The industrial fleet has been fishing this species in the coastal area of Buenos Aires province since the 1950s, and, since 1970, landings have increased sharply. Between 2000 and 2004, the artisanal fishery in the estuarine waters of Bahía Blanca collapsed. Variations in total landings of the artisanal fleet might have arisen from the environmental variables within the estuary, fishing activity in the surrounding sea region, local pressure within the estuary and/or several other variables. Our results suggest that neither oceanographic parameters nor local pressure seem to have influenced the artisanal fishery of C. guatucupa in the estuarine region. Instead, this fishery seems to have been partially influenced by the increasing fishing pressure exerted by the industrial fishing fleet operating in open waters around the estuary. This study emphasizes the need to take into account fisheries data from both the estuarine environment and the surrounding sea region, particularly when designing management plans for the sustainable use of migrating fish resources.

  14. Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae) do not seem to hybridize in natural populations

    PubMed Central

    Ferreira-Neto, Maressa; Artoni, Roberto Ferreira; Vicari, Marcelo Ricardo; Moreira-Filho, Orlando; Camacho, Juan Pedro Martínez; Bakkali, Mohammed; de Oliveira, Claudio; Foresti, Fausto

    2012-01-01

    Abstract Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept) easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers. PMID:24260650

  15. Passive acoustic detection of deep-diving beaked whales.

    PubMed

    Zimmer, Walter M X; Harwood, John; Tyack, Peter L; Johnson, Mark P; Madsen, Peter T

    2008-11-01

    Beaked whales can remain submerged for an hour or more and are difficult to sight when they come to the surface to breathe. Passive acoustic detection (PAD) not only complements traditional visual-based methods for detecting these species but also can be more effective because beaked whales produce clicks regularly to echolocate on prey during deep foraging dives. The effectiveness of PAD for beaked whales depends not only on the acoustic behavior and output of the animals but also on environmental conditions and the quality of the passive sonar implemented. A primary constraint on the range at which beaked whale clicks can be detected involves their high frequencies, which attenuate rapidly, resulting in limited ranges of detection, especially in adverse environmental conditions. Given current knowledge of source parameters and in good conditions, for example, with a wind speed of 2 ms, a receiver close to the surface should be able to detect acoustically Cuvier's beaked whales with a high probability at distances up to 0.7 km, provided the listening duration exceeds the deep dive interval, about 2.5 h on average. Detection ranges beyond 4 km are unlikely and would require low ambient noise or special sound propagation conditions.

  16. [Development of the modern biological analogy concept in the 19th century].

    PubMed

    Bäumer, A

    1989-01-01

    At the beginning of the 19th century the term analogy was still synonymous with similarity, as for example in the case of Georges Cuvier. Exact criteria for determining analogy are first found in the work of Etienne Geoffroy Saint-Hilaire. Thereupon the English scientists Sharp MacLeay, William Swainson, John Obadiah Westwood and Edwin Strickland distinguished between analogy as correspondence between certain parts of the organism, i. e. only superficial resemblance, and affinity as an essential similarity in some remarkable aspects of form. Relying on these theories Richard Owen developed his theory of analogy ("a part which has the same function as another") and homology ("the same organ in different animals under every variety of form and function"). The criteria to distinguish between these two terms had to be modified and specified when the theory of evolution was developed by Charles Darwin. In the work of Thomas Henry Huxley, Ernst Haeckel and Carl Gegenbaur the modern biological term of analogy was developed, but at the same time it lost much of its importance and homology as a criterion for natural affinity became the central objective of further biological research.

  17. A new species of Heterosentis Van Cleave, 1931 (Acanthocephala, Arhythmacanthidae), a parasite of pinguipedid fishes in the southwest Atlantic.

    PubMed

    Lanfranchi, Ana L; Timi, Juan T

    2011-02-01

    A new species of arhythmacanthid acanthocephalan, Heterosentis martini n. sp., parasitic in the Argentinean sandperch Pseudopercis semifasciata (Cuvier) (Perciformes, Pinguipedidae) from the coasts of Argentina is described. Heterosentis martini n. sp. differs from all congeneric species by having 10 longitudinal rows of hooks in the proboscis, each with 7-8 hooks, consisting of 1 medium apical and 3 larger sub-apical hooks with root, and 3-4 smaller, basal, curved hooks with rudimentary roots and spines in both ventral and dorsal regions of the body. The most similar species, Heterosentis heteracanthus (Linstow, 1896) Van Cleave, 1931, and Heterosentis brasiliensis Vieira, Felizardo and Luque, 2009, also have 10 longitudinal rows of hooks, but H. heteracanthus differs from the new species by having only 3-5 (more frequently 4) hooks in each row, with only the anterior hook large and bearing a developed root. Heterosentis brasiliensis differs from the new species by possessing 2 sub-apical hooks in each row (instead of 3), similar body length but shorter proboscis, and trunk spines restricted to the ventral surface of body.

  18. Expanded description of Neoechinorhynchus (Hebesoma) manubrianus (Acanthocephala: Neoechinorhynchidae) from marine fish in Halong Bay, Vietnam.

    PubMed

    Amin, O M; Heckmann, R A

    2012-08-01

    Neoechinorhynchus manubrianus Amin, Ha & Ha, 2011 (Acanthocephala: Neoechinorhynchidae) (formerly Neoechinorhynchus manubriensis Amin, Ha & Ha, 2011), was recently described based on optical microscopy of four males and two females (none was gravid) from caroun croaker, Johnius carouna (Cuvier), flower croaker, Nibea albiflora (Richardson), and silver croaker, Pennabia argentata (Houttuyen) (Sciaenidae) in Halong Bay, Vietnam. Subsequently, many more specimens became available from N. albiflora that were studied using SEM. SEM studies showed many additional features that were not possible to discern with optical microscopy. These included the prominent angulation of the anterior trunk, the presence of (1) anterio-dorsal and (2) undulating mid-lateral fin-like protrusions of the body wall, uniquely shaped eggs as well as details of trunk micropores, proboscis, bursa, and female gonopore. Microscopical examination of eggs from the new collection demonstrated the presence of polar prolongation of fertilization membrane which places N. manubriensis in the subgenus Hebesoma. The features of trunk angulation, trunk fins, and egg morphology further distinguish N. manubriensis from all other species of Neoechinorhynchus Stiles and Hassall, 1905 from Vietnam or from any where else in the world.

  19. Acoustic property reconstruction of a neonate Yangtze finless porpoise's (Neophocaena asiaeorientalis) head based on CT imaging.

    PubMed

    Wei, Chong; Wang, Zhitao; Song, Zhongchang; Wang, Kexiong; Wang, Ding; Au, Whitlow W L; Zhang, Yu

    2015-01-01

    The reconstruction of the acoustic properties of a neonate finless porpoise's head was performed using X-ray computed tomography (CT). The head of the deceased neonate porpoise was also segmented across the body axis and cut into slices. The averaged sound velocity and density were measured, and the Hounsfield units (HU) of the corresponding slices were obtained from computed tomography scanning. A regression analysis was employed to show the linear relationships between the Hounsfield unit and both sound velocity and density of samples. Furthermore, the CT imaging data were used to compare the HU value, sound velocity, density and acoustic characteristic impedance of the main tissues in the porpoise's head. The results showed that the linear relationships between HU and both sound velocity and density were qualitatively consistent with previous studies on Indo-pacific humpback dolphins and Cuvier's beaked whales. However, there was no significant increase of the sound velocity and acoustic impedance from the inner core to the outer layer in this neonate finless porpoise's melon.

  20. Benjamin Delessert's collections between travelers and Candolle's natural method (1803-1847).

    PubMed

    Hoquet, Thierry

    2014-09-01

    During the first half of the nineteenth century, while Georges Cuvier ruled over natural history and the Muséum d'Histoire Naturelle (MHN) was at its institutional acme, a French banker and industrialist with a Swiss family background, Benjamin Delessert, was developing an important botanical museum in Paris. His private collection included both a rich botanical library and a massive herbarium: the close integration of these two dimensions, together with the magnanimity of Delessert's patronage, contributed to making this private institution a worthy rival to the powerful and state-funded MHN. Delessert's museum had the favor of both professional and amateur naturalists. Knowledgeable and dedicated assistants (Antoine Guillemin and Antoine Lasègue) curated the collections. Moreover, Delessert was an intimate friend of the Genevan botanist Augustin- Pyramus de Candolle. Although Delessert's herbarium followed the Linnaean order, the Delessert Botanical Museum (DBM) contributed to the development of Candolle's natural system, especially through the publication of costly volumes of engravings, the Icones selectae plantarum rariorum. This essay draws together the main steps in the evolution of Delessert's collections, stressing the interdependency between books and dried plants. It focuses on the DBM as a case of cooperation between institutional and amateur expertise, private and public collections, and field collectors and cabinet naturalists.

  1. Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae) do not seem to hybridize in natural populations.

    PubMed

    Ferreira-Neto, Maressa; Artoni, Roberto Ferreira; Vicari, Marcelo Ricardo; Moreira-Filho, Orlando; Camacho, Juan Pedro Martínez; Bakkali, Mohammed; de Oliveira, Claudio; Foresti, Fausto

    2012-01-01

    Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept) easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers.

  2. Anomalies of cardiac venous drainage associated with abnormalities of cardiac conduction system.

    PubMed

    Morgan, D R; Hanratty, C G; Dixon, L J; Trimble, M; O'Keeffe, D B

    2002-07-01

    The embryological development of the superior vena cava (SVC) is complex. If the left common cardinal vein fails to occlude it can, along with the left duct of Cuvier form a left SVC, which frequently drains into the coronary sinus. This may result in abnormalities in the anatomy of this structure. A persistent left SVC occurs in 0.5% of the normal population, and 3% to 4.3% of patients with congenital heart anomalies. The pacemaking tissue of the heart is derived from two sites near the progenitors of the superior vena cava. The right-sided site forms the sinoatrial node, the left-sided site is normally carried down to an area near the coronary sinus. Out of 300 patients with cardiac rhythm abnormalities, who have undergone electrophysiological studies (EPS), or permanent pacemaker insertion (PPI), we identified 12 patients with cardiac conduction abnormalities and anomalies of venous drainage. Anomalies of the coronary sinus may be associated with abnormalities of the conduction system of the heart. This may be due to the close proximity of the coronary sinus to the final position of the left-sided primitive pacemaking tissue. In our series of 300 patients, 4% had an associated left SVC, a similar incidence to that found in previous studies of congenital heart disease.

  3. Five new species of philometrid nematodes (Philometridae) from marine fishes off Java, Indonesia.

    PubMed

    Moravec, Frantisek; Walter, Thorsten; Yuniar, Asri Trisnani

    2012-06-01

    Based on light and scanning electron microscopical studies, the following five species of the Philometridae (Nematoda: Dracunculoidea) are described from female specimens collected from marine fishes off the southwestern coast of Java, Indonesia: Philometra lobotidis sp. n. from the abdominal cavity of the Atlantic tripletail Lobotes surinamensis (Bloch) (Lobotidae, Perciformes); Philometra javaensis sp. n. from the abdominal cavity of the immaculate puffer Arothron immaculatus (Bloch et Schneider) (Tetraodontidae, Tetraodontiformes); Philometra psettoditis sp. n. from the musculature of the Indian spiny turbot Psettodes erumei (Bloch et Schneider) (Psettodidae, Pleuronectiformes); Philometroides indonesiensis sp. n. from the musculature of the hound needlefish Tylosurus crocodilus crocodilus (Péron et Lesueur) (Belonidae, Beloniformes); and Philometroides trichiuri sp. n. from the dorsal fin of the largehead hairtail Trichiurus lepturus Linnaeus (type host) and the savalai hairtail Lepturacanthus savala (Cuvier) (both Trichiuridae, Perciformes). All these new species are distinguished from their congeners parasitizing marine fishes by morphological (mainly the shape and structure of the cephalic and caudal ends and of the oesophagus) and biometrical features. Besides previously known Philometra pellucida (Jägerskiöld, 1893) and Philometra ocularis Moravec, Ogawa, Suzuki, Miyazaki et Donai, 2002, they are the only nominal philometrid species recorded from Indonesian waters.

  4. Shifting elasmobranch community assemblage at Cocos Island--an isolated marine protected area.

    PubMed

    White, Easton R; Myers, Mark C; Flemming, Joanna Mills; Baum, Julia K

    2015-08-01

    Fishing pressure has increased the extinction risk of many elasmobranch (shark and ray) species. Although many countries have established no-take marine reserves, a paucity of monitoring data means it is still unclear if reserves are effectively protecting these species. We examined data collected by a small group of divers over the past 21 years at one of the world's oldest marine protected areas (MPAs), Cocos Island National Park, Costa Rica. We used mixed effects models to determine trends in relative abundance, or probability of occurrence, of 12 monitored elasmobranch species while accounting for variation among observers and from abiotic factors. Eight of 12 species declined significantly over the past 2 decades. We documented decreases in relative abundance for 6 species, including the iconic scalloped hammerhead shark (Sphyrna lewini) (-45%), whitetip reef shark (Triaenodon obesus) (-77%), mobula ray (Mobula spp.) (-78%), and manta ray (Manta birostris) (-89%), and decreases in the probability of occurrence for 2 other species. Several of these species have small home ranges and should be better protected by an MPA, which underscores the notion that declines of marine megafauna will continue unabated in MPAs unless there is adequate enforcement effort to control fishing. In addition, probability of occurrence at Cocos Island of tiger (Galeocerdo cuvier), Galapagos (Carcharhinus galapagensis), blacktip (Carcharhinus limbatus), and whale (Rhincodon typus) sharks increased significantly. The effectiveness of MPAs cannot be evaluated by examining single species because population responses can vary depending on life history traits and vulnerability to fishing pressure. PMID:25807991

  5. Nematodes of zoonotic importance in Cynoscion guatucupa (Pisces) in the state of Rio de Janeiro.

    PubMed

    Fontenelle, Gabrielle; Knoff, Marcelo; Felizardo, Nilza Nunes; Lopes, Leila Maria Silva; Clemente, Sérgio Carmona de São

    2013-01-01

    Between January and August 2012, thirty specimens of Cynoscion guatucupa (Cuvier, 1830) caught off coast of the municipality of Itajaí, state of Santa Catarina, Brazil (26° 54' 28″ S and 48° 39' 43″ W) and commercialized in the state of Rio de Janeiro were investigated for the presence of zoonotic nematodes. In total 853 larvae of four nematode parasite species were found. There were three species of Anisakidae: three larvae of Anisakis sp., with prevalence (P) of 10%, mean intensity (MI) of 1.0, mean abundance (MA) of 0.1 and infection site (IS) in the mesentery; five of Terranova sp. with P = 13.3%, MI = 1.25, MA = 0.17, range of infection (RI) from 1 to 2 and IS = mesentery; and seven of Contracaecum sp. with P = 6.6%, MI = 3.5, MA = 0.23, RI = 1 to 4 and IS = mesentery and abdominal cavity. There was one species of Raphidascarididae: 838 larvae of Hysterothylacium deardorffoverstreetorum with P = 83.3%, MI = 33.52, MA = 27.93, RI = 1 to 219 and IS = mesentery, liver serosa and abdominal cavity. This is the first report of larvae of Anisakis sp. and Contracaecum sp in C. guatucupa in Brazil. Hysterothylacium deardorffoverstreetorum; Anisakis sp.; Terranova sp.; Contracaecum sp.; Cynoscion guatucupa. PMID:23778824

  6. Redescription and life cycle of the monorchiid Postmonorcheides maclovini Szidat, 1950 (Digenea) from the Southwestern Atlantic Ocean: Morphological and molecular data.

    PubMed

    Bagnato, Estefanía; Gilardoni, Carmen; Pina, Susana; Rodrigues, Pedro; Cremonte, Florencia

    2016-02-01

    The adult monorchiid, Postmonorcheides maclovini Szidat, 1950, digenean parasite of the Patagonian blennie Eleginops maclovinus (Cuvier) (Eleginopidae) from Puerto Deseado (47° 45' S, 65° 55' W), Argentina, was characterized and its life cycle elucidated. P. maclovinus is the only species of the genus Postmonorcheides, proposed by Szidat (1950) from Tierra del Fuego province (~54° S), Argentina. This digenean uses the Patagonian blennie as definitive host, and the intertidal bivalve Lasaea adansoni (Gmelin) (Lasaeidae) as both first and second intermediate hosts (metacercariae encyst inside sporocysts), being the first record of this clam as intermediate host of trematode parasites. The cercaria may, in addition to encysting in the sporocyst, emerge and presumably infect other intermediate hosts. This is the second report of a monorchiid species with metacercariae encysting inside the sporocyst. Adults were found parasitizing the fish stomach, pyloric caeca and intestine with a prevalence of 100%; sporocysts with cercariae and/or metacercariae were found parasitizing the gonad of the bivalve with a prevalence of 2.78%. The cercariae possess a well-developed tail and eye-spots are absent. The ITS1 sequence from the adult digeneans found in the Patagonian blennie, identified as P. maclovini, was found to be identical to the ITS1 sequences obtained both from sporocysts containing cercariae and encysted metacercariae found in L. adansoni.

  7. Anatomical transformation in mammals: developmental origin of aberrant cervical anatomy in tree sloths.

    PubMed

    Buchholtz, Emily A; Stepien, Courtney C

    2009-01-01

    Mammalian cervical count has been fixed at seven for more than 200 million years. The rare exceptions to this evolutionary constraint have intrigued anatomists since the time of Cuvier, but the developmental processes that generate them are unknown. Here we evaluate competing hypotheses for the evolutionary origin of cervical variants in Bradypus and Choloepus, tree sloths that have broken the seven cervical vertebrae barrier independently and in opposite directions. Transitional and mediolaterally disjunct anatomy characterizes the cervicothoracic vertebral boundary in each genus, although polarities are reversed. The thoracolumbar, lumbosacral, and sacrocaudal boundaries are also disrupted, and are more extreme in individuals with more extreme cervical counts. Hypotheses of homologous, homeotic, meristic, or associational transformations of traditional vertebral column anatomy are not supported by these data. We identify global homeotic repatterning of abaxial relative to primaxial mesodermal derivatives as the origin of the anomalous cervical counts of tree sloths. This interpretation emphasizes the strong resistance of the "rule of seven" to evolutionary change, as morphological stasis has been maintained primaxially coincident with the generation of a functionally longer (Bradypus) or shorter (Choloepus) neck. PMID:19196334

  8. Heredity, development and evolution: the unmodern synthesis of E.S. Russell.

    PubMed

    Esposito, Maurizio

    2013-09-01

    In 1930, while R.A. Fisher, J.B.S. Haldane, E.B. Ford and S.G. Wright were laying the foundations of what a decade later J.S. Huxley dubbed "Modern Synthesis", E.S. Russell published a groundbreaking work, The Interpretation of Development and Heredity. In this book Russell not only condemned Mendelian genetics and neo-Darwinism, but also proposed an alternative synthesis unifying heredity, development, and evolution. The book did not represent the work of a mind operating in isolation. Rather, it was a synthetic work connecting ideas and doctrines of many influential scientists working in Europe and the USA. Through the analysis of archival documents and rarely or never mentioned sources, this article provides an unconventional picture of Russell's theoretical biology. It will be shown that Russell was an international celebrity; he was at the centre of a large network of scholars who shared his ideas and insights. He was one of several biologists arguing for a different synthesis; a synthesis perhaps less visible, less institutionalised, and less 'modern', nevertheless with its influential advocates and international support. Finally, this study shows that Russell's synthesis was not rooted in the classic pantheon of towering figures in the history of biology, i.e. Darwin, Wallace, and Mendel, but was based on the teachings of Kant, Goethe, Cuvier, von Baer, and Müller.

  9. Recurrent gene loss correlates with the evolution of stomach phenotypes in gnathostome history.

    PubMed

    Castro, L Filipe C; Gonçalves, Odete; Mazan, Sylvie; Tay, Boon-Hui; Venkatesh, Byrappa; Wilson, Jonathan M

    2014-01-22

    The stomach, a hallmark of gnathostome evolution, represents a unique anatomical innovation characterized by the presence of acid- and pepsin-secreting glands. However, the occurrence of these glands in gnathostome species is not universal; in the nineteenth century the French zoologist Cuvier first noted that some teleosts lacked a stomach. Strikingly, Holocephali (chimaeras), dipnoids (lungfish) and monotremes (egg-laying mammals) also lack acid secretion and a gastric cellular phenotype. Here, we test the hypothesis that loss of the gastric phenotype is correlated with the loss of key gastric genes. We investigated species from all the main gnathostome lineages and show the specific contribution of gene loss to the widespread distribution of the agastric condition. We establish that the stomach loss correlates with the persistent and complete absence of the gastric function gene kit--H(+)/K(+)-ATPase (Atp4A and Atp4B) and pepsinogens (Pga, Pgc, Cym)--in the analysed species. We also find that in gastric species the pepsinogen gene complement varies significantly (e.g. two to four in teleosts and tens in some mammals) with multiple events of pseudogenization identified in various lineages. We propose that relaxation of purifying selection in pepsinogen genes and possibly proton pump genes in response to dietary changes led to the numerous independent events of stomach loss in gnathostome history. Significantly, the absence of the gastric genes predicts that reinvention of the stomach in agastric lineages would be highly improbable, in line with Dollo's principle.

  10. Recurrent gene loss correlates with the evolution of stomach phenotypes in gnathostome history

    PubMed Central

    Castro, L. Filipe C.; Gonçalves, Odete; Mazan, Sylvie; Tay, Boon-Hui; Venkatesh, Byrappa; Wilson, Jonathan M.

    2014-01-01

    The stomach, a hallmark of gnathostome evolution, represents a unique anatomical innovation characterized by the presence of acid- and pepsin-secreting glands. However, the occurrence of these glands in gnathostome species is not universal; in the nineteenth century the French zoologist Cuvier first noted that some teleosts lacked a stomach. Strikingly, Holocephali (chimaeras), dipnoids (lungfish) and monotremes (egg-laying mammals) also lack acid secretion and a gastric cellular phenotype. Here, we test the hypothesis that loss of the gastric phenotype is correlated with the loss of key gastric genes. We investigated species from all the main gnathostome lineages and show the specific contribution of gene loss to the widespread distribution of the agastric condition. We establish that the stomach loss correlates with the persistent and complete absence of the gastric function gene kit—H+/K+-ATPase (Atp4A and Atp4B) and pepsinogens (Pga, Pgc, Cym)—in the analysed species. We also find that in gastric species the pepsinogen gene complement varies significantly (e.g. two to four in teleosts and tens in some mammals) with multiple events of pseudogenization identified in various lineages. We propose that relaxation of purifying selection in pepsinogen genes and possibly proton pump genes in response to dietary changes led to the numerous independent events of stomach loss in gnathostome history. Significantly, the absence of the gastric genes predicts that reinvention of the stomach in agastric lineages would be highly improbable, in line with Dollo's principle. PMID:24307675

  11. Morphological and molecular characterization of Raphidascaris (Ichthyascaris) lophii (Wu, 1949) (Nematoda, Anisakidae) from marine fishes from China, with a key to the species of the subgenus Ichthyascaris.

    PubMed

    Xu, Zhen; Zhang, Lu-Ping; Liu, Bao-Chen; Li, Liang

    2012-09-01

    The little known ascaridoid nematode Raphidascaris (Ichthyascaris) lophii (Wu, 1949) is redescribed and illustrated based on newly collected specimens from the five different marine fishes: Lophius litulon (Jordan) (Lophiiformes: Lophiidae), Lophiomus setigerus (Vahl) (Lophiiformes: Lophiidae), Antennarius hispidus (Bloch et Schneider) (Lophiiformes: Antennaridae), Zeus faber Linnaeus (Zeiformes: Zeidae) and Ostichthys japonicus (Cuvier) (Beryciformes: Holocentridae) from the East and South China Sea. This species differs from all congeners in the subgenus Ichthyascaris by the length of the ventricular appendix (0.52-0.98 mm long), the number and arrangement of caudal papillae (26-32 pairs of precloacal, 3-4 pairs of paracloacal and 8-11 pairs of postcloacal) and the length of the spicules (0.49-0.88 mm long, representing 3.08-4.70% of body length). In addition, nematodes collected from these five different fishes have been characterized using molecular methods by sequencing and analysing the internal transcribed spacer (ITS) of ribosomal DNA. No variation in size and nucleotide polymorphisms is detected within the target sequence among all samples analysed. These data contribute to facilitate an accurate diagnosis of this poorly known nematode. An identification key to the species of the subgenus Ichthyascaris is also provided.

  12. Morphological and molecular evidence for a new species of the genus Dichelyne Jägerskiöld, 1902 (Ascaridida: Cucullanidae) from marine perciform fishes in the South China Sea.

    PubMed

    Li, Liang; Xu, Zhen; Zhang, Lu-Ping

    2014-10-01

    A new cucullanid nematode, Dichelyne (Dichelyne) breviculus n. sp., collected from the intestine of the goatee croaker Dendrophysa russelii (Cuvier) (Perciformes: Sciaenidae), the burrowing goby Trypauchen vagina (Bloch & Schneider) and the tropical sand goby Acentrogobius caninus (Valenciennes) (Perciformes: Gobiidae) in the South China Sea, is described using both light and scanning electron microscopy. The new species differs from its congeners in the size of body (2.16-2.96 mm in male), the position of the excretory pore and deirids, the length of the spicules (0.90-1.32 mm, representing 32.4-51.9% of body length), the arrangement of the caudal papillae and the morphology of the tail. In addition, in order to primarily assess the validity of the new species genetically, the specimens of D. breviculus n. sp. collected from the three different hosts were also characterised using molecular methods by sequencing and analysing ribosomal [small ribosomal subunit (18S rDNA) and internal transcribed spacer (ITS)] and mitochondrial [cytochrome c oxidase subunit 1 (cox1)] target regions. The molecular analyses support the validity of the new species based on the morphological observations.

  13. Meckel on developmental pathology.

    PubMed

    Opitz, John M; Schultka, Rüdiger; Göbbel, Luminita

    2006-01-15

    Before Schleiden and Schwann, Darwin and Mendel there passed briefly a towering giant, Johann Friedrich Meckel the Younger (1781-1833), now glimpsed only fleetingly and obscurely through the mist of time and former controversies, who can nowadays easily and clearly be identified as the father of a "pre-modern" developmental biology. At his beginning this prodigiously gifted physician-scholar had, as one would say nowadays, an unfair advantage, his cradle having been rocked, as it were, by the preparators in his father's and grandfather's huge collection of normal and abnormal anatomical "specimens" in the home in which he was born and raised including his father's own skeleton (with two anatomical anomalies!). Initially reluctant to follow in the steps of his illustrious anatomist/physician grandfather and father, he nevertheless early demonstrated extraordinary gifts in anatomy and zootomy. Napoleon's conquest of his homeland notwithstanding, Meckel spent at least 2 extremely fruitful years in Paris, under the tutelage of Cuvier, but also in close contact with Geoffroy St. Hilaire (Etienne), Lamarck, and von Humboldt. He not only translated Cuvier's Leçons d'anatomie comparée into German but also greatly enriched this pivotal treatise with observations of embryonic and malformed fetuses and animals only of passing interest to his mentor. In his numerous publications, Meckel was the first to relate abnormal to normal development, define anomalies of incomplete differentiation (vestigia), but, most importantly, to relate those malformations known in humans to those that are normal adult developmental states in "lower" animals (atavisms). Thus, Meckel's three-fold parallelism of the scala naturae, normal ontogeny, and the malformations in humans and animals makes him a recapitulationist par excellence, however, without ever venturing into a fully articulated and explicit theory of descent. Today Meckel is remembered solely as the discoverer of the syndrome and

  14. Patterns of top-down control in a seagrass ecosystem: could a roving apex predator induce a behaviour-mediated trophic cascade?

    PubMed

    Burkholder, Derek A; Heithaus, Michael R; Fourqurean, James W; Wirsing, Aaron; Dill, Lawrence M

    2013-11-01

    1. The loss of large-bodied herbivores and/or top predators has been associated with large-scale changes in ecosystems around the world, but there remain important questions regarding the contexts in which such changes are most likely and the mechanisms through which they occur, particularly in marine ecosystems. 2. We used long-term exclusion cages to examine the effects of large grazers (sea cows, Dugong dugon; sea turtles Chelonia mydas) on seagrass community structure, biomass and nutrient dynamics. Experiments were conducted in habitats with high risk of predation (interior of shallow banks) and lower risk (edges of banks) to elucidate whether nonconsumptive (risk) effects of tiger sharks (Galeocerdo cuvier), a roving predator, structure herbivore impacts on seagrasses. 3. In lower-risk habitats, excluding large herbivores resulted in increased leaf length for Cymodocea angustata and Halodule uninervis. C. angustata shoot densities nearly tripled when released from herbivory, while H. uninervis nearly disappeared from exclusion cages over the course of the study. 4. We found no support for the hypothesis that grazing increases seagrass nutrient content. Instead, phosphorus content was higher in seagrasses within exclosures. This pattern is consistent with decreased light availability in the denser C. angustata canopies that formed in exclosures, and may indicate that competition for light led to the decrease in H. uninervis. 5. Impacts of large grazers were consistent with a behaviour-mediated trophic cascade (BMTC) initiated by tiger sharks and mediated by risk-sensitive foraging by large grazers. 6, Our results suggest that large-bodied grazers likely played important roles in seagrass ecosystem dynamics historically and that roving predators are capable of initiating a BMTC. Conservation efforts in coastal ecosystems must account for such interactions or risk unintended consequences.

  15. On some historical and theoretical foundations of the concept of chordates.

    PubMed

    Raineri, Margherita

    2009-03-01

    The concept of chordates arose from the alliance between embryology and evolution in the second half of the nineteenth century, as a result of a theoretical elaboration on Kowalevsky's discoveries about some fundamental similarities between the ontogeny of the lancelet, a putative primitive fish, and that of ascidians, then classified as molluscs. Carrying out his embryological studies in the light of Darwin's theory and von Baer's account of the germ layers, Kowalevsky was influenced by the German tradition of idealistic morphology that was concerned with transformations driven by laws of form, rather than with a gradual evolution occurring by means of variation, selection and adaptation. In agreement with this tradition, Kowalevsky interpreted the vertebrate-like structures of the ascidian larva according to von Kölliker's model of heterogeneous generation. Then, he asserted the homology of the germ layers and their derivatives in different types of animals and suggested a common descent of annelids and vertebrates, in agreement with Saint-Hilaire's hypothesis of the unity of composition of body plans, but in contrast with Haeckel's idea of the Chordonia (chordates). In The Descent of Man Darwin quoted Kowalevsky's discoveries, but accepted Haeckel's interpretation of the ascidian embryology within the frame of a monophyletic tree of life that was produced by the fundamental biogenetic law. Joining embryology to evolution in the light of idealistic morphology, the biogenetic law turned out to be instrumental in bringing forth different evolutionary hypotheses: it was used by Haeckel and Darwin to link vertebrates to invertebrates by means of the concept of chordates, and by Kowalevsky to corroborate the annelid theory of the origin of vertebrates. Yet, there was still another interpretation of Kowalevsky's discoveries. As an adherent to empiricism and to Cuvier's theory of types, von Baer asserted that these discoveries did not prove convincingly a dorsal

  16. The shark assemblage at French Frigate Shoals atoll, Hawai'i: species composition, abundance and habitat use.

    PubMed

    Dale, Jonathan J; Stankus, Austin M; Burns, Michael S; Meyer, Carl G

    2011-01-01

    Empirical data on the abundance and habitat preferences of coral reef top predators are needed to evaluate their ecological impacts and guide management decisions. We used longline surveys to quantify the shark assemblage at French Frigate Shoals (FFS) atoll from May to August 2009. Fishing effort consisted of 189 longline sets totaling 6,862 hook hours of soak time. A total of 221 sharks from 7 species were captured, among which Galapagos (Carcharhinus galapagensis, 36.2%), gray reef (Carcharhinus amblyrhynchos, 25.8%) and tiger (Galeocerdo cuvier, 20.4%) sharks were numerically dominant. A lack of blacktip reef sharks (Carcharhinus melanopterus) distinguished the FFS shark assemblage from those at many other atolls in the Indo-Pacific. Compared to prior underwater visual survey estimates, longline methods more accurately represented species abundance and composition for the majority of shark species. Sharks were significantly less abundant in the shallow lagoon than adjacent habitats. Recaptures of Galapagos sharks provided the first empirical estimate of population size for any Galapagos shark population. The overall recapture rate was 5.4%. Multiple closed population models were evaluated, with Chao M(h) ranking best in model performance and yielding a population estimate of 668 sharks with 95% confidence intervals ranging from 289-1720. Low shark abundance in the shallow lagoon habitats suggests removal of a small number of sharks from the immediate vicinity of lagoonal islets may reduce short-term predation on endangered monk seal (Monachus schauinslandi) pups, but considerable fishing effort would be required to catch even a small number of sharks. Additional data on long-term movements and habitat use of sharks at FFS are required to better assess the likely ecological impacts of shark culling. PMID:21347321

  17. Establishment of Infection Models in Zebrafish Larvae (Danio rerio) to Study the Pathogenesis of Aeromonas hydrophila.

    PubMed

    Saraceni, Paolo R; Romero, Alejandro; Figueras, Antonio; Novoa, Beatriz

    2016-01-01

    Aeromonas hydrophila is a Gram-negative opportunistic pathogen of fish and terrestrial animals. In humans, A. hydrophila mainly causes gastroenteritis, septicaemia, and tissue infections. The mechanisms of infection, the main virulence factors and the host immune response triggered by A. hydrophila have been studied in detail using murine models and adult fish. However, the great limitation of studying adult animals is that the animal must be sacrificed and its tissues/organs extracted, which prevents the study of the infectious processes in the whole living animal. Zebrafish larvae are being used for the analysis of several infectious diseases, but their use for studying the pathogenesis of A. hydrophila has never been explored. The great advantage of zebrafish larvae is their transparency during the first week after fertilization, which allows detailed descriptions of the infectious processes using in vivo imaging techniques such as differential interferential contrast (DIC) and fluorescence microscopy. Moreover, the availability of fluorescent pathogens and transgenic reporter zebrafish lines expressing fluorescent immune cells, immune marker genes or cytokines/chemokines allows the host-pathogen interactions to be characterized. The present study explores the suitability of zebrafish larvae to study the pathogenesis of A. hydrophila and the interaction mechanisms between the bacterium and the innate immune responses through an infection model using different routes for infection. We used an early-embryo infection model at 3 days post-fertilization (dpf) through the microinjection of A. hydrophila into the duct of Cuvier, caudal vein, notochord, or muscle and two bath infection models using 4 dpf healthy and injured larvae. The latter resembled the natural conditions under which A. hydrophila produces infectious diseases in animals. We compared the cellular processes after infection in each anatomical site by confocal fluorescence imaging and determined the

  18. Not all sharks are "swimming noses": variation in olfactory bulb size in cartilaginous fishes.

    PubMed

    Yopak, Kara E; Lisney, Thomas J; Collin, Shaun P

    2015-03-01

    Olfaction is a universal modality by which all animals sample chemical stimuli from their environment. In cartilaginous fishes, olfaction is critical for various survival tasks including localizing prey, avoiding predators, and chemosensory communication with conspecifics. Little is known, however, about interspecific variation in olfactory capability in these fishes, or whether the relative importance of olfaction in relation to other sensory systems varies with regard to ecological factors, such as habitat and lifestyle. In this study, we have addressed these questions by directly examining interspecific variation in the size of the olfactory bulbs (OB), the region of the brain that receives the primary sensory projections from the olfactory nerve, in 58 species of cartilaginous fishes. Relative OB size was compared among species occupying different ecological niches. Our results show that the OBs maintain a substantial level of allometric independence from the rest of the brain across cartilaginous fishes and that OB size is highly variable among species. These findings are supported by phylogenetic generalized least-squares models, which show that this variability is correlated with ecological niche, particularly habitat. The relatively largest OBs were found in pelagic-coastal/oceanic sharks, especially migratory species such as Carcharodon carcharias and Galeocerdo cuvier. Deep-sea species also possess large OBs, suggesting a greater reliance on olfaction in habitats where vision may be compromised. In contrast, the smallest OBs were found in the majority of reef-associated species, including sharks from the families Carcharhinidae and Hemiscyllidae and dasyatid batoids. These results suggest that there is great variability in the degree to which these fishes rely on olfactory cues. The OBs have been widely used as a neuroanatomical proxy for olfactory capability in vertebrates, and we speculate that differences in olfactory capabilities may be the result of

  19. Comparative Use of a Caribbean Mesophotic Coral Ecosystem and Association with Fish Spawning Aggregations by Three Species of Shark.

    PubMed

    Pickard, Alexandria E; Vaudo, Jeremy J; Wetherbee, Bradley M; Nemeth, Richard S; Blondeau, Jeremiah B; Kadison, Elizabeth A; Shivji, Mahmood S

    2016-01-01

    Understanding of species interactions within mesophotic coral ecosystems (MCEs; ~ 30-150 m) lags well behind that for shallow coral reefs. MCEs are often sites of fish spawning aggregations (FSAs) for a variety of species, including many groupers. Such reproductive fish aggregations represent temporal concentrations of potential prey that may be drivers of habitat use by predatory species, including sharks. We investigated movements of three species of sharks within a MCE and in relation to FSAs located on the shelf edge south of St. Thomas, United States Virgin Islands. Movements of 17 tiger (Galeocerdo cuvier), seven lemon (Negaprion brevirostris), and six Caribbean reef (Carcharhinus perezi) sharks tagged with acoustic transmitters were monitored within the MCE using an array of acoustic receivers spanning an area of 1,060 km2 over a five year period. Receivers were concentrated around prominent grouper FSAs to monitor movements of sharks in relation to these temporally transient aggregations. Over 130,000 detections of telemetered sharks were recorded, with four sharks tracked in excess of 3 years. All three shark species were present within the MCE over long periods of time and detected frequently at FSAs, but patterns of MCE use and orientation towards FSAs varied both spatially and temporally among species. Lemon sharks moved over a large expanse of the MCE, but concentrated their activities around FSAs during grouper spawning and were present within the MCE significantly more during grouper spawning season. Caribbean reef sharks were present within a restricted portion of the MCE for prolonged periods of time, but were also absent for long periods. Tiger sharks were detected throughout the extent of the acoustic array, with the MCE representing only portion of their habitat use, although a high degree of individual variation was observed. Our findings indicate that although patterns of use varied, all three species of sharks repeatedly utilized the MCE and

  20. Long-Term Changes in Species Composition and Relative Abundances of Sharks at a Provisioning Site

    PubMed Central

    Brunnschweiler, Juerg M.; Abrantes, Kátya G.; Barnett, Adam

    2014-01-01

    Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today’s recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier) displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas) of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004–2006 and 2007–2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004–2006 and very rare in the period of 2007–2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive exclusion

  1. How man-made interference might cause gas bubble emboli in deep diving whales.

    PubMed

    Fahlman, Andreas; Tyack, Peter L; Miller, Patrick J O; Kvadsheim, Petter H

    2014-01-01

    Recent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS). It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N2 levels, thereby increasing DCS risk. Dive data recorded from sperm, killer, long-finned pilot, Blainville's beaked and Cuvier's beaked whales before and during exposure to low- (1-2 kHz) and mid- (2-7 kHz) frequency active sonar were used to estimate the changes in blood and tissue N2 tension (PN2 ). Our objectives were to determine if differences in (1) dive behavior or (2) physiological responses to sonar are plausible risk factors for bubble formation. The theoretical estimates indicate that all species may experience high N2 levels. However, unexpectedly, deep diving generally result in higher end-dive PN2 as compared with shallow diving. In this focused review we focus on three possible explanations: (1) We revisit an old hypothesis that CO2, because of its much higher diffusivity, forms bubble precursors that continue to grow in N2 supersaturated tissues. Such a mechanism would be less dependent on the alveolar collapse depth but affected by elevated levels of CO2 following a burst of activity during sonar exposure. (2) During deep dives, a greater duration of time might be spent at depths where gas exchange continues as compared with shallow dives. The resulting elevated levels of N2 in deep diving whales might also make them more susceptible to anthropogenic disturbances. (3) Extended duration of dives even at depths beyond where the alveoli collapse could result in slow continuous accumulation of N2 in the adipose tissues that eventually becomes a liability.

  2. Crossing latitudes--long-distance tracking of an apex predator.

    PubMed

    Ferreira, Luciana C; Thums, Michele; Meeuwig, Jessica J; Vianna, Gabriel M S; Stevens, John; McAuley, Rory; Meekan, Mark G

    2015-01-01

    Tiger sharks (Galeocerdo cuvier) are apex predators occurring in most tropical and warm temperate marine ecosystems, but we know relatively little of their patterns of residency and movement over large spatial and temporal scales. We deployed satellite tags on eleven tiger sharks off the north-western coast of Western Australia and used the Brownian Bridge kernel method to calculate home ranges and analyse movement behaviour. One individual recorded one of the largest geographical ranges of movement ever reported for the species, travelling over 4000 km during 517 days of monitoring. Tags on the remainder of the sharks reported for shorter periods (7-191 days). Most of these sharks had restricted movements and long-term (30-188 days) residency in coastal waters in the vicinity of the area where they were tagged. Core home range areas of sharks varied greatly from 1166.9 to 634,944 km2. Tiger sharks spent most of their time in water temperatures between 23°-26°C but experienced temperatures ranging from 6°C to 33°C. One shark displayed seasonal movements among three distinct home range cores spread along most of the coast of Western Australia and generalized linear models showed that this individual had different patterns of temperature and depth occupancy in each region of the coast, with the highest probability of residency occurring in the shallowest areas of the coast with water temperatures above 23°C. These results suggest that tiger sharks can migrate over very large distances and across latitudes ranging from tropical to the cool temperate waters. Such extensive long-term movements may be a key element influencing the connectivity of populations within and among ocean basins.

  3. The Shark Assemblage at French Frigate Shoals Atoll, Hawai‘i: Species Composition, Abundance and Habitat Use

    PubMed Central

    Dale, Jonathan J.; Stankus, Austin M.; Burns, Michael S.; Meyer, Carl G.

    2011-01-01

    Empirical data on the abundance and habitat preferences of coral reef top predators are needed to evaluate their ecological impacts and guide management decisions. We used longline surveys to quantify the shark assemblage at French Frigate Shoals (FFS) atoll from May to August 2009. Fishing effort consisted of 189 longline sets totaling 6,862 hook hours of soak time. A total of 221 sharks from 7 species were captured, among which Galapagos (Carcharhinus galapagensis, 36.2%), gray reef (Carcharhinus amblyrhynchos, 25.8%) and tiger (Galeocerdo cuvier, 20.4%) sharks were numerically dominant. A lack of blacktip reef sharks (Carcharhinus melanopterus) distinguished the FFS shark assemblage from those at many other atolls in the Indo-Pacific. Compared to prior underwater visual survey estimates, longline methods more accurately represented species abundance and composition for the majority of shark species. Sharks were significantly less abundant in the shallow lagoon than adjacent habitats. Recaptures of Galapagos sharks provided the first empirical estimate of population size for any Galapagos shark population. The overall recapture rate was 5.4%. Multiple closed population models were evaluated, with Chao Mh ranking best in model performance and yielding a population estimate of 668 sharks with 95% confidence intervals ranging from 289–1720. Low shark abundance in the shallow lagoon habitats suggests removal of a small number of sharks from the immediate vicinity of lagoonal islets may reduce short-term predation on endangered monk seal (Monachus schauinslandi) pups, but considerable fishing effort would be required to catch even a small number of sharks. Additional data on long-term movements and habitat use of sharks at FFS are required to better assess the likely ecological impacts of shark culling. PMID:21347321

  4. Cytochrome P4501A1 expression in blubber biopsies of endangered false killer whales (Pseudorca crassidens) and nine other odontocete species from Hawai'i.

    PubMed

    Foltz, Kerry M; Baird, Robin W; Ylitalo, Gina M; Jensen, Brenda A

    2014-11-01

    Odontocetes (toothed whales) are considered sentinel species in the marine environment because of their high trophic position, long life spans, and blubber that accumulates lipophilic contaminants. Cytochrome P4501A1 (CYP1A1) is a biomarker of exposure and molecular effects of certain persistent organic pollutants. Immunohistochemistry was used to visualize CYP1A1 expression in blubber biopsies collected by non-lethal sampling methods from 10 species of free-ranging Hawaiian odontocetes: short-finned pilot whale, melon-headed whale, pygmy killer whale, common bottlenose dolphin, rough-toothed dolphin, pantropical spotted dolphin, Blainville's beaked whale, Cuvier's beaked whale, sperm whale, and endangered main Hawaiian Islands insular false killer whale. Significantly higher levels of CYP1A1 were observed in false killer whales and rough-toothed dolphins compared to melon-headed whales, and in general, trophic position appears to influence CYP1A1 expression patterns in particular species groups. No significant differences in CYP1A1 were found based on age class or sex across all samples. However, within male false killer whales, juveniles expressed significantly higher levels of CYP1A1 when compared to adults. Total polychlorinated biphenyl (∑PCBs) concentrations in 84% of false killer whales exceeded proposed threshold levels for health effects, and ∑PCBs correlated with CYP1A1 expression. There was no significant relationship between PCB toxic equivalent quotient and CYP1A1 expression, suggesting that this response may be influenced by agonists other than the dioxin-like PCBs measured in this study. No significant differences were found for CYP1A1 expression among social clusters of false killer whales. This work provides a foundation for future health monitoring of the endangered stock of false killer whales and other Hawaiian odontocetes.

  5. Validation of a randomization procedure to assess animal habitat preferences: microhabitat use of tiger sharks in a seagrass ecosystem.

    PubMed

    Heithaus, Michael R; Hamilton, Ian M; Wirsing, Aaron J; Dill, Lawrence M

    2006-05-01

    1. Tiger sharks Galeocerdo cuvier are important predators in a variety of nearshore communities, including the seagrass ecosystem of Shark Bay, Western Australia. Because tiger sharks are known to influence spatial distributions of multiple prey species, it is important to understand how they use habitats at a variety of spatial scales. We used a combination of catch rates and acoustic tracking to determine tiger shark microhabitat use in Shark Bay. 2. Comparing habitat-use data from tracking against the null hypothesis of no habitat preference is hindered in Shark Bay, as elsewhere, by the difficulty of defining expected habitat use given random movement. We used randomization procedures to generate expected habitat use in the absence of habitat preference and expected habitat use differences among groups (e.g. males and females). We tested the performance of these protocols using simulated data sets with known habitat preferences. 3. The technique correctly classified sets of simulated tracks as displaying a preference or not and was a conservative test for differences in habitat preferences between subgroups of tracks (e.g. males vs. females). 4. Sharks preferred shallow habitats over deep ones, and preferred shallow edge microhabitats over shallow interior ones. The use of shallow edges likely increases encounter rates with potential prey and may have profound consequences for the dynamics of Shark Bay's seagrass ecosystem through indirect effects transmitted by grazers that are common prey of tiger sharks. 5. Females showed a greater tendency to use shallow edge microhabitats than did males; this pattern was not detected by traditional analysis techniques. 6. The randomization procedures presented here are applicable to many field studies that use tracking by allowing researchers both to determine overall habitat preferences and to identify differences in habitat use between groups within their sample.

  6. Evaluating the landscape of fear between apex predatory sharks and mobile sea turtles across a large dynamic seascape.

    PubMed

    Hammerschlag, Neil; Broderick, Annette C; Coker, John W; Coyne, Michael S; Dodd, Mark; Frick, Michael G; Godfrey, Matthew H; Godley, Brendan J; Griffin, DuBose B; Hartog, Kyra; Murphy, Sally R; Murphy, Thomas M; Nelson, Emily Rose; Williams, Kristina L; Witt, Matthew J; Hawkes, Lucy A

    2015-08-01

    The "landscape of fear" model has been proposed as a unifying concept in ecology, describing, in part, how animals behave and move about in their environment. The basic model predicts that as an animal's landscape changes from low to high risk of predation, prey species will alter their behavior to risk avoidance. However, studies investigating and evaluating the landscape of fear model across large spatial scales (tens to hundreds of thousands of square kilometers) in dynamic, open, aquatic systems involving apex predators and highly mobile prey are lacking. To address this knowledge gap, we investigated predator-prey relationships between. tiger sharks (Galeocerdo cuvier) and loggerhead turtles (Caretta caretta) in the North Atlantic Ocean. This included the use of satellite tracking to examine shark and turtle distributions as well as their surfacing behaviors under varying levels of home range overlap. Our findings revealed patterns that deviated from our a priori predictions based on the landscape of fear model. Specifically, turtles did not alter their surfacing behaviors to risk avoidance when overlap in shark-turtle core home range was high. However, in areas of high overlap with turtles, sharks exhibited modified surfacing behaviors that may enhance predation opportunity. We suggest that turtles may be an important factor in determining shark,distribution, whereas for turtles, other life history trade-offs may play a larger role in defining their habitat use. We propose that these findings are a result of both biotic and physically driven factors that independently or synergistically affect predator-prey interactions in this system. These results have implications for evolutionary biology, community ecology; and wildlife conservation. Further, given the difficulty in studying highly migratory marine species, our approach and conclusions may be applied to the study of other predator-prey systems. PMID:26405737

  7. Genetic and morphological evidence reveals the existence of a new family, genus and species of Echinorhynchida (Acanthocephala).

    PubMed

    Braicovich, Paola E; Lanfranchi, Ana L; Farber, Marisa D; Marvaldi, Adriana E; Luque, José L; Timi, Juan T

    2014-08-01

    Gymnorhadinorhynchus gen. n. is proposed to accommodate its type species, G. decapteri sp. n., a parasite of the marine fish Decapterus punctatus (Cuvier), caught from the coastal waters of Brazil. Gymnorhadinorhynchus decapteri sp. n. was morphologically most similar to species of two echinorhynchid families, the Rhadinorhynchidae and the Cavisomidae, particularly in the structure of the proboscis and the absence of somatic spines, respectively. This combination of morphological features made it difficult to assign our specimen to an extant family of the Acanthocephala. Therefore, in order to clarify the systematic placement of G. decapteri, a molecular phylogenetic analysis was performed based on the SSU and LSU rDNA and the mitochondrial cox1 gene sequences obtained for the new taxon and other 26 acanthocephalan species. The results of parsimony and maximum likelihood analyses, using individual, combined and concatenated sequence data, consistently indicate that the specimens do not belong to any known family of the Echinorhynchida. Rather, G. decapteri represents a distinct lineage that is closely related to the Transvenidae, but distantly related to both the Rhadinorhynchidae and the Cavisomidae. Gymnorhadinorhynchidae fam. n. is therefore erected. This newly described family can be distinguished from other families of Echinorhynchida by the combination of the following morphological characters: a proboscis cylindrical with 10 rows of 22-26 hooks, dorsoventral differences in proboscis hooks, basal hooks forming a ring and being abruptly larger than anterior hooks, absence of trunk spines and presence of four tubular cement glands. This combination, in addition to several molecular autapomorphies, justifies the erection of a new genus, Gymnorhadinorhynchus gen. n., in order to accommodate this new species. PMID:25185409

  8. A Comparison of the Seasonal Movements of Tiger Sharks and Green Turtles Provides Insight into Their Predator-Prey Relationship

    PubMed Central

    Fitzpatrick, Richard; Thums, Michele; Bell, Ian; Meekan, Mark G.; Stevens, John D.; Barnett, Adam

    2012-01-01

    During the reproductive season, sea turtles use a restricted area in the vicinity of their nesting beaches, making them vulnerable to predation. At Raine Island (Australia), the highest density green turtle Chelonia mydas rookery in the world, tiger sharks Galeocerdo cuvier have been observed to feed on green turtles, and it has been suggested that they may specialise on such air-breathing prey. However there is little information with which to examine this hypothesis. We compared the spatial and temporal components of movement behaviour of these two potentially interacting species in order to provide insight into the predator-prey relationship. Specifically, we tested the hypothesis that tiger shark movements are more concentrated at Raine Island during the green turtle nesting season than outside the turtle nesting season when turtles are not concentrated at Raine Island. Turtles showed area-restricted search behaviour around Raine Island for ∼3–4 months during the nesting period (November–February). This was followed by direct movement (transit) to putative foraging grounds mostly in the Torres Straight where they switched to area-restricted search mode again, and remained resident for the remainder of the deployment (53–304 days). In contrast, tiger sharks displayed high spatial and temporal variation in movement behaviour which was not closely linked to the movement behaviour of green turtles or recognised turtle foraging grounds. On average, tiger sharks were concentrated around Raine Island throughout the year. While information on diet is required to determine whether tiger sharks are turtle specialists our results support the hypothesis that they target this predictable and plentiful prey during turtle nesting season, but they might not focus on this less predictable food source outside the nesting season. PMID:23284819

  9. Delineating the Exmouth Mantle Plume (NW Australia) : Implications for the Origin of Volcanic Margins

    NASA Astrophysics Data System (ADS)

    Rohrman, M. H.

    2014-12-01

    Denudation and magmatism are distinct characteristics of Large Igneous Provinces, such as the Northwest Australian volcanic margin. Unfortunately, its temporal and spatial extent is poorly defined. Here, I present a simple isostatic model relating denudation to plume induced lithospheric thinning and underplating to delineate the Late Jurassic/Early Cretaceous Exmouth mantle plume. This upwelling was centered on a highly extended and subsided continental fragment known as the subsea Sonne/Sonja Ridge area and includes the Cuvier Margin (CM) and Cape Range Fracture Zone (CRFZ). The region is characterized by ~3 km denudation and ~ 500 m tectonic uplift, with erosion products acting as provenance for the Early Cretaceous Lower Barrow delta. Partial melting of the plume generated an underplate, characterized as a high velocity body (HVB) on seismic data. Denudation analysis indicates that only ~40 % of the HVB is melt related, with the effective underplate ~ 4 km thick at the plume centre, decreasing in the outer regions. Widespread plume induced convective lithospheric thinning set the boundary conditions for subsequent extension related magmatism and breakup in the Valanginian, as recorded by subsidence analysis of exploration wells. Hot plume derived material flowed to regions under extension, initiating additional magmatism now observed as SDRs (Seaward Dipping Reflectors series), initially thick magmatic crust, followed by normal ocean spreading in the Hauterivian. After initial upwelling, the thermal plume can be traced in a western direction as a hotspot to the Quokka Rise in the mid Cretaceous, before terminating after 35 - 50 Ma of activity. These findings suggest that most volcanic margins are generated by plume upwellings that are relatively passive features, with uplift consisting of a combination of plume induced convective lithospheric thinning and underplating. Melt migration and mantle heating subsequently lower stresses and facilitate breakup.

  10. Evaluating the landscape of fear between apex predatory sharks and mobile sea turtles across a large dynamic seascape.

    PubMed

    Hammerschlag, Neil; Broderick, Annette C; Coker, John W; Coyne, Michael S; Dodd, Mark; Frick, Michael G; Godfrey, Matthew H; Godley, Brendan J; Griffin, DuBose B; Hartog, Kyra; Murphy, Sally R; Murphy, Thomas M; Nelson, Emily Rose; Williams, Kristina L; Witt, Matthew J; Hawkes, Lucy A

    2015-08-01

    The "landscape of fear" model has been proposed as a unifying concept in ecology, describing, in part, how animals behave and move about in their environment. The basic model predicts that as an animal's landscape changes from low to high risk of predation, prey species will alter their behavior to risk avoidance. However, studies investigating and evaluating the landscape of fear model across large spatial scales (tens to hundreds of thousands of square kilometers) in dynamic, open, aquatic systems involving apex predators and highly mobile prey are lacking. To address this knowledge gap, we investigated predator-prey relationships between. tiger sharks (Galeocerdo cuvier) and loggerhead turtles (Caretta caretta) in the North Atlantic Ocean. This included the use of satellite tracking to examine shark and turtle distributions as well as their surfacing behaviors under varying levels of home range overlap. Our findings revealed patterns that deviated from our a priori predictions based on the landscape of fear model. Specifically, turtles did not alter their surfacing behaviors to risk avoidance when overlap in shark-turtle core home range was high. However, in areas of high overlap with turtles, sharks exhibited modified surfacing behaviors that may enhance predation opportunity. We suggest that turtles may be an important factor in determining shark,distribution, whereas for turtles, other life history trade-offs may play a larger role in defining their habitat use. We propose that these findings are a result of both biotic and physically driven factors that independently or synergistically affect predator-prey interactions in this system. These results have implications for evolutionary biology, community ecology; and wildlife conservation. Further, given the difficulty in studying highly migratory marine species, our approach and conclusions may be applied to the study of other predator-prey systems.

  11. State-dependent risk-taking by green sea turtles mediates top-down effects of tiger shark intimidation in a marine ecosystem.

    PubMed

    Heithaus, Michael R; Frid, Alejandro; Wirsing, Aaron J; Dill, Lawrence M; Fourqurean, James W; Burkholder, Derek; Thomson, Jordan; Bejder, Lars

    2007-09-01

    1. A predictive framework of community and ecosystem dynamics that applies across systems has remained elusive, in part because non-consumptive predator effects are often ignored. Further, it is unclear how much individual-level detail community models must include. 2. Previous studies of short-lived species suggest that state-dependent decisions add little to our understanding of community dynamics. Body condition-dependent decisions made by long-lived herbivores under risk of predation, however, might have greater community-level effects. This possibility remains largely unexplored, especially in marine environments. 3. In the relatively pristine seagrass community of Shark Bay, Australia, we found that herbivorous green sea turtles (Chelonia mydas Linnaeus, 1758) threatened by tiger sharks (Galeocerdo cuvier Peron and LeSueur, 1822) select microhabitats in a condition-dependent manner. Turtles in poor body condition selected profitable, high-risk microhabitats, while turtles in good body condition, which are more abundant, selected safer, less profitable microhabitats. When predation risk was low, however, turtles in good condition moved into more profitable microhabitats. 4. Condition-dependent use of space by turtles shows that tiger sharks modify the spatio-temporal pattern of turtle grazing and their impacts on ecosystem dynamics (a trait-mediated indirect interaction). Therefore, state-dependent decisions by individuals can have important implications for community dynamics in some situations. 5. Our study suggests that declines in large-bodied sharks may affect ecosystems more substantially than assumed when non-lethal effects of these top predators on mesoconsumers are not considered explicitly.

  12. The Oxford Companion to the Earth

    NASA Astrophysics Data System (ADS)

    Hancock, Paul L.

    2001-06-01

    Here is a wealth of information on planet Earth, ranging from the heights of the ionsphere down to the red-hot molten core. Written by some 200 expert contributors, and illustrated with over 600 pictures, including 16 pages of color plates, The Oxford Companion to the Earth offers 900 alphabetically arranged entries that cover everything from deserts and wetlands to mountains, caves, glaciers, and coral reefs. There are articles on natural phenomena such as tornadoes and tsunamis, volcanoes and earthquakes, jet streams and weather fronts; on the history of Earth, including the origin of life, Burgess Shale fauna, dinosaurs, and the Ice Ages; on key figures, such as Agassiz, Cuvier, Darwin, and Lamarck; and on such important ecological concerns as acid rain, the ozone layer, industrial waste disposal, and the greenhouse effect. The Companion also examines the great sources of wealth to be found in the Earth, from coal and oil to gold, silver, and diamonds, and many curious land formations, from sinkholes and fiords to yardangs and quicksand. There are brief entries on rock types, from amber to travertine, and extensive essays on cutting-edge aspects of the earth sciences, such as seismology and marine geology. The Companion includes extensive cross-references, suggested further reading, an index, and many useful appendices, with a geological timescale, facts and figures about the Earth, and a table of chemical elements. The Oxford Companion to the Earth is a unique reference work, offering unrivaled coverage of our home planet. Generously illustrated and vividly written, it is a treasure house of information for all lovers of natural history, geology, and ecology, whether professional or amateur.

  13. A comparison of the seasonal movements of tiger sharks and green turtles provides insight into their predator-prey relationship.

    PubMed

    Fitzpatrick, Richard; Thums, Michele; Bell, Ian; Meekan, Mark G; Stevens, John D; Barnett, Adam

    2012-01-01

    During the reproductive season, sea turtles use a restricted area in the vicinity of their nesting beaches, making them vulnerable to predation. At Raine Island (Australia), the highest density green turtle Chelonia mydas rookery in the world, tiger sharks Galeocerdo cuvier have been observed to feed on green turtles, and it has been suggested that they may specialise on such air-breathing prey. However there is little information with which to examine this hypothesis. We compared the spatial and temporal components of movement behaviour of these two potentially interacting species in order to provide insight into the predator-prey relationship. Specifically, we tested the hypothesis that tiger shark movements are more concentrated at Raine Island during the green turtle nesting season than outside the turtle nesting season when turtles are not concentrated at Raine Island. Turtles showed area-restricted search behaviour around Raine Island for ∼3-4 months during the nesting period (November-February). This was followed by direct movement (transit) to putative foraging grounds mostly in the Torres Straight where they switched to area-restricted search mode again, and remained resident for the remainder of the deployment (53-304 days). In contrast, tiger sharks displayed high spatial and temporal variation in movement behaviour which was not closely linked to the movement behaviour of green turtles or recognised turtle foraging grounds. On average, tiger sharks were concentrated around Raine Island throughout the year. While information on diet is required to determine whether tiger sharks are turtle specialists our results support the hypothesis that they target this predictable and plentiful prey during turtle nesting season, but they might not focus on this less predictable food source outside the nesting season. PMID:23284819

  14. Crossing latitudes--long-distance tracking of an apex predator.

    PubMed

    Ferreira, Luciana C; Thums, Michele; Meeuwig, Jessica J; Vianna, Gabriel M S; Stevens, John; McAuley, Rory; Meekan, Mark G

    2015-01-01

    Tiger sharks (Galeocerdo cuvier) are apex predators occurring in most tropical and warm temperate marine ecosystems, but we know relatively little of their patterns of residency and movement over large spatial and temporal scales. We deployed satellite tags on eleven tiger sharks off the north-western coast of Western Australia and used the Brownian Bridge kernel method to calculate home ranges and analyse movement behaviour. One individual recorded one of the largest geographical ranges of movement ever reported for the species, travelling over 4000 km during 517 days of monitoring. Tags on the remainder of the sharks reported for shorter periods (7-191 days). Most of these sharks had restricted movements and long-term (30-188 days) residency in coastal waters in the vicinity of the area where they were tagged. Core home range areas of sharks varied greatly from 1166.9 to 634,944 km2. Tiger sharks spent most of their time in water temperatures between 23°-26°C but experienced temperatures ranging from 6°C to 33°C. One shark displayed seasonal movements among three distinct home range cores spread along most of the coast of Western Australia and generalized linear models showed that this individual had different patterns of temperature and depth occupancy in each region of the coast, with the highest probability of residency occurring in the shallowest areas of the coast with water temperatures above 23°C. These results suggest that tiger sharks can migrate over very large distances and across latitudes ranging from tropical to the cool temperate waters. Such extensive long-term movements may be a key element influencing the connectivity of populations within and among ocean basins. PMID:25671609

  15. Declining abundance of beaked whales (family Ziphiidae) in the California Current large marine ecosystem.

    PubMed

    Moore, Jeffrey E; Barlow, Jay P

    2013-01-01

    Beaked whales are among the most diverse yet least understood groups of marine mammals. A diverse set of mostly anthropogenic threats necessitates improvement in our ability to assess population status for this cryptic group. The Southwest Fisheries Science Center (NOAA) conducted six ship line-transect cetacean abundance surveys in the California Current off the contiguous western United States between 1991 and 2008. We used a Bayesian hidden-process modeling approach to estimate abundance and population trends of beaked whales using sightings data from these surveys. We also compiled records of beaked whale stranding events (3 genera, at least 8 species) on adjacent beaches from 1900 to 2012, to help assess population status of beaked whales in the northern part of the California Current. Bayesian posterior summaries for trend parameters provide strong evidence of declining beaked whale abundance in the study area. The probability of negative trend for Cuvier's beaked whale (Ziphius cavirostris) during 1991-2008 was 0.84, with 1991 and 2008 estimates of 10771 (CV = 0.51) and ≈7550 (CV = 0.55), respectively. The probability of decline for Mesoplodon spp. (pooled across species) was 0.96, with 1991 and 2008 estimates of 2206 (CV = 0.46) and 811 (CV = 0.65). The mean posterior estimates for average rate of decline were 2.9% and 7.0% per year. There was no evidence of abundance trend for Baird's beaked whale (Berardius bairdii), for which annual abundance estimates in the survey area ranged from ≈900 to 1300 (CV≈1.3). Stranding data were consistent with the survey results. Causes of apparent declines are unknown. Direct impacts of fisheries (bycatch) can be ruled out, but impacts of anthropogenic sound (e.g., naval active sonar) and ecosystem change are plausible hypotheses that merit investigation.

  16. Long-term changes in species composition and relative abundances of sharks at a provisioning site.

    PubMed

    Brunnschweiler, Juerg M; Abrantes, Kátya G; Barnett, Adam

    2014-01-01

    Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today's recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier) displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas) of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004-2006 and 2007-2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004-2006 and very rare in the period of 2007-2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive exclusion among shark

  17. The shark assemblage at French Frigate Shoals atoll, Hawai'i: species composition, abundance and habitat use.

    PubMed

    Dale, Jonathan J; Stankus, Austin M; Burns, Michael S; Meyer, Carl G

    2011-02-10

    Empirical data on the abundance and habitat preferences of coral reef top predators are needed to evaluate their ecological impacts and guide management decisions. We used longline surveys to quantify the shark assemblage at French Frigate Shoals (FFS) atoll from May to August 2009. Fishing effort consisted of 189 longline sets totaling 6,862 hook hours of soak time. A total of 221 sharks from 7 species were captured, among which Galapagos (Carcharhinus galapagensis, 36.2%), gray reef (Carcharhinus amblyrhynchos, 25.8%) and tiger (Galeocerdo cuvier, 20.4%) sharks were numerically dominant. A lack of blacktip reef sharks (Carcharhinus melanopterus) distinguished the FFS shark assemblage from those at many other atolls in the Indo-Pacific. Compared to prior underwater visual survey estimates, longline methods more accurately represented species abundance and composition for the majority of shark species. Sharks were significantly less abundant in the shallow lagoon than adjacent habitats. Recaptures of Galapagos sharks provided the first empirical estimate of population size for any Galapagos shark population. The overall recapture rate was 5.4%. Multiple closed population models were evaluated, with Chao M(h) ranking best in model performance and yielding a population estimate of 668 sharks with 95% confidence intervals ranging from 289-1720. Low shark abundance in the shallow lagoon habitats suggests removal of a small number of sharks from the immediate vicinity of lagoonal islets may reduce short-term predation on endangered monk seal (Monachus schauinslandi) pups, but considerable fishing effort would be required to catch even a small number of sharks. Additional data on long-term movements and habitat use of sharks at FFS are required to better assess the likely ecological impacts of shark culling.

  18. Better Fitness in Captive Cuvier’s Gazelle despite Inbreeding Increase: Evidence of Purging?

    PubMed Central

    Moreno, Eulalia; Pérez-González, Javier; Carranza, Juan; Moya-Laraño, Jordi

    2015-01-01

    Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive population of Cuvier's gazelle managed under a European Endangered Species Programme since 1975. Previous results in this population have shown that highly inbred mothers tend to produce more daughters, and this fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as surplus individuals in the population). Here, by using studbook data we explore whether purging has occurred in the population by investigating whether after the change in pairing strategy a) inbreeding and homozygosity increased at the population level, b) fitness (survival) increased, and c) the relationship between inbreeding and juvenile survival, was positive. Consistent with the existence of purging, we found an increase in inbreeding coefficients, homozygosity and juvenile survival. In addition, we showed that in the course of the breeding programme the relationship between inbreeding and juvenile survival was not uniform but rather changed over time: it was negative in the early years, flat in the middle years and positive after the change in pairing strategy. We highlight that by allowing inbred individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable managing strategy to reduce the surplus of males that force most zoos to use ethical culling and euthanizing management tools. We discuss these possibilities but also acknowledge that many other effects

  19. Not all sharks are "swimming noses": variation in olfactory bulb size in cartilaginous fishes.

    PubMed

    Yopak, Kara E; Lisney, Thomas J; Collin, Shaun P

    2015-03-01

    Olfaction is a universal modality by which all animals sample chemical stimuli from their environment. In cartilaginous fishes, olfaction is critical for various survival tasks including localizing prey, avoiding predators, and chemosensory communication with conspecifics. Little is known, however, about interspecific variation in olfactory capability in these fishes, or whether the relative importance of olfaction in relation to other sensory systems varies with regard to ecological factors, such as habitat and lifestyle. In this study, we have addressed these questions by directly examining interspecific variation in the size of the olfactory bulbs (OB), the region of the brain that receives the primary sensory projections from the olfactory nerve, in 58 species of cartilaginous fishes. Relative OB size was compared among species occupying different ecological niches. Our results show that the OBs maintain a substantial level of allometric independence from the rest of the brain across cartilaginous fishes and that OB size is highly variable among species. These findings are supported by phylogenetic generalized least-squares models, which show that this variability is correlated with ecological niche, particularly habitat. The relatively largest OBs were found in pelagic-coastal/oceanic sharks, especially migratory species such as Carcharodon carcharias and Galeocerdo cuvier. Deep-sea species also possess large OBs, suggesting a greater reliance on olfaction in habitats where vision may be compromised. In contrast, the smallest OBs were found in the majority of reef-associated species, including sharks from the families Carcharhinidae and Hemiscyllidae and dasyatid batoids. These results suggest that there is great variability in the degree to which these fishes rely on olfactory cues. The OBs have been widely used as a neuroanatomical proxy for olfactory capability in vertebrates, and we speculate that differences in olfactory capabilities may be the result of

  20. Long-term changes in species composition and relative abundances of sharks at a provisioning site.

    PubMed

    Brunnschweiler, Juerg M; Abrantes, Kátya G; Barnett, Adam

    2014-01-01

    Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today's recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier) displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas) of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004-2006 and 2007-2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004-2006 and very rare in the period of 2007-2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive exclusion among shark

  1. Cytochrome P4501A1 expression in blubber biopsies of endangered false killer whales (Pseudorca crassidens) and nine other odontocete species from Hawai'i.

    PubMed

    Foltz, Kerry M; Baird, Robin W; Ylitalo, Gina M; Jensen, Brenda A

    2014-11-01

    Odontocetes (toothed whales) are considered sentinel species in the marine environment because of their high trophic position, long life spans, and blubber that accumulates lipophilic contaminants. Cytochrome P4501A1 (CYP1A1) is a biomarker of exposure and molecular effects of certain persistent organic pollutants. Immunohistochemistry was used to visualize CYP1A1 expression in blubber biopsies collected by non-lethal sampling methods from 10 species of free-ranging Hawaiian odontocetes: short-finned pilot whale, melon-headed whale, pygmy killer whale, common bottlenose dolphin, rough-toothed dolphin, pantropical spotted dolphin, Blainville's beaked whale, Cuvier's beaked whale, sperm whale, and endangered main Hawaiian Islands insular false killer whale. Significantly higher levels of CYP1A1 were observed in false killer whales and rough-toothed dolphins compared to melon-headed whales, and in general, trophic position appears to influence CYP1A1 expression patterns in particular species groups. No significant differences in CYP1A1 were found based on age class or sex across all samples. However, within male false killer whales, juveniles expressed significantly higher levels of CYP1A1 when compared to adults. Total polychlorinated biphenyl (∑PCBs) concentrations in 84% of false killer whales exceeded proposed threshold levels for health effects, and ∑PCBs correlated with CYP1A1 expression. There was no significant relationship between PCB toxic equivalent quotient and CYP1A1 expression, suggesting that this response may be influenced by agonists other than the dioxin-like PCBs measured in this study. No significant differences were found for CYP1A1 expression among social clusters of false killer whales. This work provides a foundation for future health monitoring of the endangered stock of false killer whales and other Hawaiian odontocetes. PMID:25134676

  2. How man-made interference might cause gas bubble emboli in deep diving whales.

    PubMed

    Fahlman, Andreas; Tyack, Peter L; Miller, Patrick J O; Kvadsheim, Petter H

    2014-01-01

    Recent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS). It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N2 levels, thereby increasing DCS risk. Dive data recorded from sperm, killer, long-finned pilot, Blainville's beaked and Cuvier's beaked whales before and during exposure to low- (1-2 kHz) and mid- (2-7 kHz) frequency active sonar were used to estimate the changes in blood and tissue N2 tension (PN2 ). Our objectives were to determine if differences in (1) dive behavior or (2) physiological responses to sonar are plausible risk factors for bubble formation. The theoretical estimates indicate that all species may experience high N2 levels. However, unexpectedly, deep diving generally result in higher end-dive PN2 as compared with shallow diving. In this focused review we focus on three possible explanations: (1) We revisit an old hypothesis that CO2, because of its much higher diffusivity, forms bubble precursors that continue to grow in N2 supersaturated tissues. Such a mechanism would be less dependent on the alveolar collapse depth but affected by elevated levels of CO2 following a burst of activity during sonar exposure. (2) During deep dives, a greater duration of time might be spent at depths where gas exchange continues as compared with shallow dives. The resulting elevated levels of N2 in deep diving whales might also make them more susceptible to anthropogenic disturbances. (3) Extended duration of dives even at depths beyond where the alveoli collapse could result in slow continuous accumulation of N2 in the adipose tissues that eventually becomes a liability. PMID:24478724

  3. Crossing Latitudes—Long-Distance Tracking of an Apex Predator

    PubMed Central

    Ferreira, Luciana C.; Thums, Michele; Meeuwig, Jessica J.; Vianna, Gabriel M. S.; Stevens, John; McAuley, Rory; Meekan, Mark G.

    2015-01-01

    Tiger sharks (Galeocerdo cuvier) are apex predators occurring in most tropical and warm temperate marine ecosystems, but we know relatively little of their patterns of residency and movement over large spatial and temporal scales. We deployed satellite tags on eleven tiger sharks off the north-western coast of Western Australia and used the Brownian Bridge kernel method to calculate home ranges and analyse movement behaviour. One individual recorded one of the largest geographical ranges of movement ever reported for the species, travelling over 4000 km during 517 days of monitoring. Tags on the remainder of the sharks reported for shorter periods (7-191 days). Most of these sharks had restricted movements and long-term (30-188 days) residency in coastal waters in the vicinity of the area where they were tagged. Core home range areas of sharks varied greatly from 1166.9 to 634,944 km2. Tiger sharks spent most of their time in water temperatures between 23°-26°C but experienced temperatures ranging from 6°C to 33°C. One shark displayed seasonal movements among three distinct home range cores spread along most of the coast of Western Australia and generalized linear models showed that this individual had different patterns of temperature and depth occupancy in each region of the coast, with the highest probability of residency occurring in the shallowest areas of the coast with water temperatures above 23°C. These results suggest that tiger sharks can migrate over very large distances and across latitudes ranging from tropical to the cool temperate waters. Such extensive long-term movements may be a key element influencing the connectivity of populations within and among ocean basins. PMID:25671609

  4. How man-made interference might cause gas bubble emboli in deep diving whales

    PubMed Central

    Fahlman, Andreas; Tyack, Peter L.; Miller, Patrick J. O.; Kvadsheim, Petter H.

    2014-01-01

    Recent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS). It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N2 levels, thereby increasing DCS risk. Dive data recorded from sperm, killer, long-finned pilot, Blainville's beaked and Cuvier's beaked whales before and during exposure to low- (1–2 kHz) and mid- (2–7 kHz) frequency active sonar were used to estimate the changes in blood and tissue N2 tension (PN2). Our objectives were to determine if differences in (1) dive behavior or (2) physiological responses to sonar are plausible risk factors for bubble formation. The theoretical estimates indicate that all species may experience high N2 levels. However, unexpectedly, deep diving generally result in higher end-dive PN2 as compared with shallow diving. In this focused review we focus on three possible explanations: (1) We revisit an old hypothesis that CO2, because of its much higher diffusivity, forms bubble precursors that continue to grow in N2 supersaturated tissues. Such a mechanism would be less dependent on the alveolar collapse depth but affected by elevated levels of CO2 following a burst of activity during sonar exposure. (2) During deep dives, a greater duration of time might be spent at depths where gas exchange continues as compared with shallow dives. The resulting elevated levels of N2 in deep diving whales might also make them more susceptible to anthropogenic disturbances. (3) Extended duration of dives even at depths beyond where the alveoli collapse could result in slow continuous accumulation of N2 in the adipose tissues that eventually becomes a liability. PMID:24478724

  5. Declining Abundance of Beaked Whales (Family Ziphiidae) in the California Current Large Marine Ecosystem

    PubMed Central

    Moore, Jeffrey E.; Barlow, Jay P.

    2013-01-01

    Beaked whales are among the most diverse yet least understood groups of marine mammals. A diverse set of mostly anthropogenic threats necessitates improvement in our ability to assess population status for this cryptic group. The Southwest Fisheries Science Center (NOAA) conducted six ship line-transect cetacean abundance surveys in the California Current off the contiguous western United States between 1991 and 2008. We used a Bayesian hidden-process modeling approach to estimate abundance and population trends of beaked whales using sightings data from these surveys. We also compiled records of beaked whale stranding events (3 genera, at least 8 species) on adjacent beaches from 1900 to 2012, to help assess population status of beaked whales in the northern part of the California Current. Bayesian posterior summaries for trend parameters provide strong evidence of declining beaked whale abundance in the study area. The probability of negative trend for Cuvier's beaked whale (Ziphius cavirostris) during 1991–2008 was 0.84, with 1991 and 2008 estimates of 10771 (CV = 0.51) and ≈7550 (CV = 0.55), respectively. The probability of decline for Mesoplodon spp. (pooled across species) was 0.96, with 1991 and 2008 estimates of 2206 (CV = 0.46) and 811 (CV = 0.65). The mean posterior estimates for average rate of decline were 2.9% and 7.0% per year. There was no evidence of abundance trend for Baird's beaked whale (Berardius bairdii), for which annual abundance estimates in the survey area ranged from ≈900 to 1300 (CV≈1.3). Stranding data were consistent with the survey results. Causes of apparent declines are unknown. Direct impacts of fisheries (bycatch) can be ruled out, but impacts of anthropogenic sound (e.g., naval active sonar) and ecosystem change are plausible hypotheses that merit investigation. PMID:23341907

  6. Molecular genetic identification of southern hemisphere beaked whales (Cetacea: Ziphiidae).

    PubMed

    Dalebout, M L; Helden, A V; van Waerebeek, K; Baker, C S

    1998-06-01

    To assist in the species-level identification of stranded and hunted beaked whales, we compiled a database of 'reference' sequences from the mitochondrial DNA control region for 15 of the 20 described ziphiid species. Reference samples for eight species were obtained from stranded animals in New Zealand and South Australia. Sequences for a further seven species were obtained from a previously published report. This database was used to identify 20 'test' samples obtained from incompletely documented strandings around New Zealand. Analyses showed that four of these 'test' specimens (20%) had initially been misidentified. These included two animals of particular interest: (i) a Blainville's beaked whale (Mesoplodon densirostris), the first record of this species in New Zealand waters; and, (ii) a juvenile Andrews' beaked whale (Mesoplodon bowdoini), a species known from just over 20 strandings worldwide. A published sequence from a beaked whale product purchased in the Republic of Korea was identified as a Cuvier's beaked whale (Ziphius cavirostris). Levels of intra- and interspecific variation were compared to determine the potential for misidentification when the database or taxonomy is incomplete. Intraspecific variation was generally < 2%, and interspecific divergence was generally > 4.7%. Exceptions were within-species variation in Hyperoodon planifrons, southern bottlenosed whale (4.12%), which exceeded the variation between the two species of Berardius (3.78%), and variation between the two specimens assigned to M. hectori, Hector's beaked whale (7.14%). The latter case appears to be an error in species identification, and could represent the discovery of a new species of beaked whale.

  7. "Gas and fat embolic syndrome" involving a mass stranding of beaked whales (family Ziphiidae) exposed to anthropogenic sonar signals.

    PubMed

    Fernández, A; Edwards, J F; Rodríguez, F; Espinosa de los Monteros, A; Herráez, P; Castro, P; Jaber, J R; Martín, V; Arbelo, M

    2005-07-01

    A study of the lesions of beaked whales (BWs) in a recent mass stranding in the Canary Islands following naval exercises provides a possible explanation of the relationship between anthropogenic, acoustic (sonar) activities and the stranding and death of marine mammals. Fourteen BWs were stranded in the Canary Islands close to the site of an international naval exercise (Neo-Tapon 2002) held on 24 September 2002. Strandings began about 4 hours after the onset of midfrequency sonar activity. Eight Cuvier's BWs (Ziphius cavirostris), one Blainville's BW (Mesoplodon densirostris), and one Gervais' BW (Mesoplodon europaeus) were examined postmortem and studied histopathologically. No inflammatory or neoplastic processes were noted, and no pathogens were identified. Macroscopically, whales had severe, diffuse congestion and hemorrhage, especially around the acoustic jaw fat, ears, brain, and kidneys. Gas bubble-associated lesions and fat embolism were observed in the vessels and parenchyma of vital organs. In vivo bubble formation associated with sonar exposure that may have been exacerbated by modified diving behavior caused nitrogen supersaturation above a threshold value normally tolerated by the tissues (as occurs in decompression sickness). Alternatively, the effect that sonar has on tissues that have been supersaturated with nitrogen gas could be such that it lowers the threshold for the expansion of in vivo bubble precursors (gas nuclei). Exclusively or in combination, these mechanisms may enhance and maintain bubble growth or initiate embolism. Severely injured whales died or became stranded and died due to cardiovascular collapse during beaching. The present study demonstrates a new pathologic entity in cetaceans. The syndrome is apparently induced by exposure to mid-frequency sonar signals and particularly affects deep, long-duration, repetitive-diving species like BWs.

  8. Kudoa saudiensis sp. n. (Myxosporea: Multivalvulida) infecting oocytes of the Indian mackerel Rastrelliger kanagurta (Perciformes: Scombridae).

    PubMed

    Mansour, Lamjed; Harrath, Abdel Halim; Abdel-Baki, Abdel-Azeem S; Al-Quraishy, Saleh; Al, Suliman Y Omar

    2015-01-01

    During a survey the occurrence of Kudoa quraishii Mansour, Harrath, Abd-Elkader, Alwasel, Abdel-Baki et Al Omar, 2014, recently identified in the muscles of the Indian mackerel, Rastrelliger kanagurta (Cuvier), a species of Kudoa Meglitsch, 1947 infecting oocytes of mature females of the same host fish was found. The new species, for which the name Kudoa saudiensis sp. n. is proposed, infects oocytes that are enlarged with a whitish colour. The parasite develops in vesicular polysporous plasmodia within the oocyte. Infection occurs with a mean prevalence of 20% (7/35) of examined females. Mature spores are quadratic in shape in apical view, having four equal valves and four symmetrical polar capsules. Fresh spores are 2.4-3.6 µm long (mean ± SD 3.1 ± 0.3 µm), 4.3-5.4 µm (4.7 ± 0.3 µm) wide and 3.4-4.3 µm (3.8 ± 0.3 µm) in thickness and long. The smaller size of the new Kudoa species was the distinctive feature that separates it from all previously described species. Molecular analysis based on the SSU rDNA sequences shows that the highest percentage of similarity of 98.5% was observed with K. ovivora Swearer et Robertson, 1999, reported from oocytes of labroid fish from the Caribbean coasts of Panama. The percentage of similarity was 98% with K. azevedoi Mansour, Thabet, Chourabi, Harrath, Gtari, Al Omar et Ben Hassine, 2013 and 89% with K. quraishii. Phylogenetic analysis of the SSU and LSU rDNA data revealed a consistent of the new species with K. azevedoi and K. ovivora. Our findings support the creation of Kudoa saudiensis sp. n. that infects oocytes of the Indian mackerel Rastrelliger kanagurta. PMID:25960554

  9. [James Parkinson (1755-1824) revisited].

    PubMed

    Poirier, Jacques

    2013-03-01

    The name of Parkinson is universally famous because of the eponymous disease. But as a man, James Parkinson (1755-1824), is poorly known. He was born, married and passed away in his St-Leonard parish in Shoreditch (London). After having studied Latin, Greek, natural philosophy, and stenography (shorthand), which he considered as the basic tools of any doctor, he studied for six months at the London Hospital Medical College, and served his apprenticeship as an apothecary-surgeon with his father for six years. Then he was qualified as a surgeon in 1784 at the age of 29 years. His activity has been deployed in three areas: 1) medicine, 2) political activism and social reformism, 3) paleontology and oryctology. As a physician, Parkinson has published several books, the most important concerned paralysis agitans (future Parkinson's disease), gout, complications of lightning (future Lichtenberg figures and keraunoparalysis), acute appendicitis (with his son John Parkinson) and hernias (diagnosis, development, dangers of hernia ruptures, and design of a simple truss). Its ideological and political commitment was manifested by joining two secret societies and publishing numerous pamphlets, many of which are signed by the pseudonym Old Hubert; he campaigned for a better representation of the people in Parliament, for greater social justice, for the defense and recognition of the rights of the poor, the insane, the children, and against children abuse. He published a small compendium of chemistry, he was one of the thirteen members who create the British Geological Society and is recognized as one of the founders of paleontology; as was Georges Cuvier (1769-1832), he remained a strong supporter of creationism and catastrophism. Distinguished oryctologist, he gave his name to several fossils, mainly molluscs. PMID:23508322

  10. Charles Lyell and scientific thinking in geology

    NASA Astrophysics Data System (ADS)

    Virgili, Carmina

    2007-07-01

    Charles Lyell (1797-1875) was born at Kinnordy, Scotland. His father, an amateur botanist, and his grandfather, a navigator, gave him very soon a taste for the observation of the Nature. He went to the Oxford University to study classical literature, but he also followed the geological course of William Buckland. After having been employed as jurist for some years, in 1827 he decided on a career of geologist and held the chair of geology of the King's College of London, from 1831 on. He was a contemporary of Cuvier, Darwin, von Humboldt, Hutton, Lavoisier, and was elected 'membre correspondant' of the 'Académie des sciences, France', in January 1862. Charles Lyell is one of the eminent geologists who initiated the scientific thinking in geology, in which his famous volumes of the Principles of Geology were taken as the authority. These reference volumes are based on multiple observations and field works collected during numerous fieldtrips in western Europe (principally Spain, France, and Italy) and North America. To his name are attached, among others: ( i) the concept of uniformitarism (or actualism), which was opposed to the famous catastrophism, in vogue at that time, and which may be summarized by the expression "The present is the key to the past"; ( ii) the division of the Tertiary in three series denominated Eocene, Miocene, and Pliocene, due to the study of the age of strata by fossil faunas; ( iii) the theory according to which the orogenesis of a mountain chain, as the Pyrenees, results from different pulsations on very long time scales and was not induced by a unique pulsation during a short and intense period. The uniformity of the laws of Nature is undeniably a principle Charles Lyell was the first to state clearly and to apply to the study of the whole Earth's crust, which opened a new era in geology.

  11. Genetic and morphological evidence reveals the existence of a new family, genus and species of Echinorhynchida (Acanthocephala).

    PubMed

    Braicovich, Paola E; Lanfranchi, Ana L; Farber, Marisa D; Marvaldi, Adriana E; Luque, José L; Timi, Juan T

    2014-08-01

    Gymnorhadinorhynchus gen. n. is proposed to accommodate its type species, G. decapteri sp. n., a parasite of the marine fish Decapterus punctatus (Cuvier), caught from the coastal waters of Brazil. Gymnorhadinorhynchus decapteri sp. n. was morphologically most similar to species of two echinorhynchid families, the Rhadinorhynchidae and the Cavisomidae, particularly in the structure of the proboscis and the absence of somatic spines, respectively. This combination of morphological features made it difficult to assign our specimen to an extant family of the Acanthocephala. Therefore, in order to clarify the systematic placement of G. decapteri, a molecular phylogenetic analysis was performed based on the SSU and LSU rDNA and the mitochondrial cox1 gene sequences obtained for the new taxon and other 26 acanthocephalan species. The results of parsimony and maximum likelihood analyses, using individual, combined and concatenated sequence data, consistently indicate that the specimens do not belong to any known family of the Echinorhynchida. Rather, G. decapteri represents a distinct lineage that is closely related to the Transvenidae, but distantly related to both the Rhadinorhynchidae and the Cavisomidae. Gymnorhadinorhynchidae fam. n. is therefore erected. This newly described family can be distinguished from other families of Echinorhynchida by the combination of the following morphological characters: a proboscis cylindrical with 10 rows of 22-26 hooks, dorsoventral differences in proboscis hooks, basal hooks forming a ring and being abruptly larger than anterior hooks, absence of trunk spines and presence of four tubular cement glands. This combination, in addition to several molecular autapomorphies, justifies the erection of a new genus, Gymnorhadinorhynchus gen. n., in order to accommodate this new species.

  12. The Holocene paleo-tsunami history of West Australia

    NASA Astrophysics Data System (ADS)

    Scheffers, S. R.; Scheffers, A.; Kelletat, D.; Bryant, E. A.

    2008-06-01

    West Australian coastlines experienced several tsunamis in mid-Holocene times. To expand our knowledge about Holocene tsunami events in West Australia, the authors extended the previously studied spatial scale to include the central- and south-western coastlines. Several of the discovered events were mid- and young Holocene (≤ 1000 yr BP) tsunami impacts on the outer coast of the Cape Range Peninsula. Five hundred kilometres to the south between Cape Cuvier and Point Quobba, additional tsunami evidence exists on top of steep cliffs over a coastal stretch of 30 km. The sedimentary signature of two tsunamis is documented in this area by wide ridges comprised of sand, shell, and clasts (including coral fragments) at heights of 12-30 m asl and 300-500 m inland. Enigmatic boulders (20-100 tons) appear as cliff-top megaclasts up to 100 m inland. Here, radiocarbon dating revealed a minimum of two tsunami events: at 5700 yr BP with waves depositing sandy ridges far inland and at approximately 1000 yr BP with waves depositing boulders originating from the marine environment. As the first dates are congruent with previously published results for the Learmonth region 500 km to the north, we assume that the same mid-Holocene tsunami hits this long coastal section as well. The southwestern coast of West Australia from Cape Naturaliste to Albany also shows signs of impacts by extreme waves. Here, huge granite boulders (80-400 tons) were dislocated and transported to heights up to 10 m above sea level. The most prominent dislocated boulders were positioned at Merchant Rock (Cape Naturaliste National Park), at Islet near Nanarup, and in Cave Bay close to Albany.

  13. Contrasting patterns of individual specialization and trophic coupling in two marine apex predators.

    PubMed

    Matich, Philip; Heithaus, Michael R; Layman, Craig A

    2011-01-01

    1. Apex predators are often assumed to be dietary generalists and, by feeding on prey from multiple basal nutrient sources, serve to couple discrete food webs. But there is increasing evidence that individual level dietary specialization may be common in many species, and this has not been investigated for many marine apex predators. 2. Because of their position at or near the top of many marine food webs, and the possibility that they can affect populations of their prey and induce trophic cascades, it is important to understand patterns of dietary specialization in shark populations. 3. Stable isotope values from body tissues with different turnover rates were used to quantify patterns of individual specialization in two species of 'generalist' sharks (bull sharks, Carcharhinus leucas, and tiger sharks, Galeocerdo cuvier). 4. Despite wide population-level isotopic niche breadths in both species, isotopic values of individual tiger sharks varied across tissues with different turnover rates. The population niche breadth was explained mostly by variation within individuals suggesting tiger sharks are true generalists. In contrast, isotope values of individual bull sharks were stable through time and their wide population level niche breadth was explained by variation among specialist individuals. 5. Relative resource abundance and spatial variation in food-predation risk tradeoffs may explain the differences in patterns of specialization between shark species. 6. The differences in individual dietary specialization between tiger sharks and bull sharks results in different functional roles in coupling or compartmentalizing distinct food webs. 7. Individual specialization may be an important feature of trophic dynamics of highly mobile marine top predators and should be explicitly considered in studies of marine food webs and the ecological role of top predators. PMID:20831730

  14. The metazoan parasite communities of the Argentinean sandperch Pseudopercis semifasciata (Pisces: Perciformes) and their use to elucidate the stock structure of the host.

    PubMed

    Timi, J T; Lanfranchi, A L

    2009-09-01

    The use of parasites as biological tags allowed the identification of 3 stocks of Argentinean sandperch, Pseudopercis semifasciata (Cuvier), in the Argentine Sea. A total of 100 specimens caught in 3 zones: Villa Gesell (37 degrees 15'S, 57 degrees 23'W; n=20), Miramar (38 degrees 03'S, 57 degrees 30'W-38 degrees 44'S, 58 degrees 44'W; n=30) and Península Valdes (42 degrees 00'-42 degrees 45'S; n=50), were examined and 28 parasite species were found, 15 of them being new host records. Both univariate and multivariate analyses identified discrete stocks in each zone. The observed differences were not related to the host size or sex. Each locality was characterized by its own indicator species. Villa Gesell was typified by unidentified cestode plerocercoids, Corynosoma cetaceum and Hysterothylacium sp., Miramar by Heterosentis sp. and Pseudoterranova sp. and Península Valdes by A. simplex s.l. Fishes from both northern localities shared gnathiid pranizae, Corynosoma australe and Grillotia sp. as indicators, whereas Miramar and Península Valdes shared only Trifur tortuosus. The most distant localities showed no indicator species in common. Discriminant analyses of parasite assemblages agreed with populational comparisons in identifying the same set of biological tags, whereas some differences in the identity of indicator species were obtained by similarity analysis. However, the 3 approaches were congruent in identifying Grillotia sp., C. australe and C. cetaceum as indicators of northern localities, and A. simplex s.l. as related to Patagonian waters. Differences among zones could be enhanced by the sedentary habits, limited dispersal and high site fidelity of P. semifasciata, and their spawning in rocky outcrops, which are isolated environments. PMID:19627631

  15. Comparative Use of a Caribbean Mesophotic Coral Ecosystem and Association with Fish Spawning Aggregations by Three Species of Shark

    PubMed Central

    Pickard, Alexandria E.; Vaudo, Jeremy J.; Wetherbee, Bradley M.; Nemeth, Richard S.; Blondeau, Jeremiah B.; Kadison, Elizabeth A.; Shivji, Mahmood S.

    2016-01-01

    Understanding of species interactions within mesophotic coral ecosystems (MCEs; ~ 30–150 m) lags well behind that for shallow coral reefs. MCEs are often sites of fish spawning aggregations (FSAs) for a variety of species, including many groupers. Such reproductive fish aggregations represent temporal concentrations of potential prey that may be drivers of habitat use by predatory species, including sharks. We investigated movements of three species of sharks within a MCE and in relation to FSAs located on the shelf edge south of St. Thomas, United States Virgin Islands. Movements of 17 tiger (Galeocerdo cuvier), seven lemon (Negaprion brevirostris), and six Caribbean reef (Carcharhinus perezi) sharks tagged with acoustic transmitters were monitored within the MCE using an array of acoustic receivers spanning an area of 1,060 km2 over a five year period. Receivers were concentrated around prominent grouper FSAs to monitor movements of sharks in relation to these temporally transient aggregations. Over 130,000 detections of telemetered sharks were recorded, with four sharks tracked in excess of 3 years. All three shark species were present within the MCE over long periods of time and detected frequently at FSAs, but patterns of MCE use and orientation towards FSAs varied both spatially and temporally among species. Lemon sharks moved over a large expanse of the MCE, but concentrated their activities around FSAs during grouper spawning and were present within the MCE significantly more during grouper spawning season. Caribbean reef sharks were present within a restricted portion of the MCE for prolonged periods of time, but were also absent for long periods. Tiger sharks were detected throughout the extent of the acoustic array, with the MCE representing only portion of their habitat use, although a high degree of individual variation was observed. Our findings indicate that although patterns of use varied, all three species of sharks repeatedly utilized the MCE

  16. Establishment of Infection Models in Zebrafish Larvae (Danio rerio) to Study the Pathogenesis of Aeromonas hydrophila

    PubMed Central

    Saraceni, Paolo R.; Romero, Alejandro; Figueras, Antonio; Novoa, Beatriz

    2016-01-01

    Aeromonas hydrophila is a Gram-negative opportunistic pathogen of fish and terrestrial animals. In humans, A. hydrophila mainly causes gastroenteritis, septicaemia, and tissue infections. The mechanisms of infection, the main virulence factors and the host immune response triggered by A. hydrophila have been studied in detail using murine models and adult fish. However, the great limitation of studying adult animals is that the animal must be sacrificed and its tissues/organs extracted, which prevents the study of the infectious processes in the whole living animal. Zebrafish larvae are being used for the analysis of several infectious diseases, but their use for studying the pathogenesis of A. hydrophila has never been explored. The great advantage of zebrafish larvae is their transparency during the first week after fertilization, which allows detailed descriptions of the infectious processes using in vivo imaging techniques such as differential interferential contrast (DIC) and fluorescence microscopy. Moreover, the availability of fluorescent pathogens and transgenic reporter zebrafish lines expressing fluorescent immune cells, immune marker genes or cytokines/chemokines allows the host–pathogen interactions to be characterized. The present study explores the suitability of zebrafish larvae to study the pathogenesis of A. hydrophila and the interaction mechanisms between the bacterium and the innate immune responses through an infection model using different routes for infection. We used an early-embryo infection model at 3 days post-fertilization (dpf) through the microinjection of A. hydrophila into the duct of Cuvier, caudal vein, notochord, or muscle and two bath infection models using 4 dpf healthy and injured larvae. The latter resembled the natural conditions under which A. hydrophila produces infectious diseases in animals. We compared the cellular processes after infection in each anatomical site by confocal fluorescence imaging and determined the

  17. A survey of nematodes of the genus Cucullanus Müller, 1777 (Nematoda, Seuratoidea) parasitic in marine fishes off Brazil, including description of three new species.

    PubMed

    Vieira, Fabiano M; Pereira, Felipe B; Pantoja, Camila; Soares, Iris A; Pereira, Aldenice N; Timi, Juan T; Scholz, Tomáš; Luque, José L

    2015-11-05

    A taxonomic survey of six nematode species (including three new taxa) from the genus Cucullanus Müller, 1777, parasites of marine fishes off the Brazilian coast, is provided. Nematodes were studied using light and scanning electron microscopy (SEM). Cucullanus gastrophysi n. sp. parasitic in Lophius gastrophysus Miranda Ribeiro differs from its congeners by the combination of the following features: shape and number of sclerotized structures in the oesophastome (a pair of lateral elongate structures and a single small reniform one), position of deirids and excretory pore (both anterior to oesophagus base), spicule length and spicule/body length ratio (0.97-1.29 mm and 6.5-10.5%, respectively), morphology and length of gubernaculum (V-shaped, 107-135 µm long). Cucullanus protrudens n. sp. from Pagrus pagrus (Linnaeus) has the cloacal lips broadly protruded, which differentiates it from several species of Cucullanus; other features, e.g., the length of spicules and gubernaculum (400-415 µm and 91-103 µm, respectively), arrangement of caudal papillae and position of excretory pore (slightly posterior to oesophagus-intestine junction) also characterize this species. Cucullanus pseudopercis n. sp. from Pseudopercis semifasciata (Cuvier) has deirids and excretory pore posterior to the oesophagus-intestine junction, which distinguishes the species from most of the congeners; furthermore, the arrangement of caudal papillae in combination with the length of spicules and gubernaculum (1.0-1.5 mm and 178-196 µm, respectively) separate this species from other taxa. Newly collected specimens of C. cirratus Müller, 1777 (type species of the genus) from Urophycis brasiliensis (Kaup), C. pedroi from Conger orbignianus Valenciennes (type host of the species) and C. genypteri Sardella, Navone & Timi, 1997 from Genypterus brasiliensis Regan, were studied as well. Comparisons between newly collected samples and the taxonomic data available for each respective species revealed

  18. Natural selection and the conditions for existence: representational vs. conditional teleology in biological explanation.

    PubMed

    Reiss, John O

    2005-01-01

    Human intentional action, including the design and use of artifacts, involves the prior mental representation of the goal (end) and the means to achieve that goal. This representation is part of the efficient cause of the action, and thus can be used to explain both the action and the achievement of the end. This is intentional teleological explanation. More generally, teleological explanation that depends on the real existence of a representation of the goal (and the means to achieve it) can be called representational teleological explanation. Such explanations in biology can involve both external representations (e.g., ideas in the mind of God) and internal representations (souls, vital powers, entelechies, developmental programs, etc.). However, another type of explanation of intentional action (or any other process) is possible. Given that an action achieving a result occurs, the action can be explained as fulfilling the necessary conditions (means) for that result (end), and, reciprocally, the result explained by the occurrence of those necessary conditions. This is conditional teleological explanation. For organisms, natural selection is often understood metaphorically as the designer, intentionally constructing them for certain ends. Unfortunately, this metaphor is often taken rather too literally, because it has been difficult to conceive of another way to relate natural selection to the process of evolution. I argue that combining a conditional teleological explanation of organisms and of evolution provides such an alternative. This conditional teleology can be grounded in existence or survival. Given that an organism exists, we can explain its existence by the occurrence of the necessary conditions for that existence. This principle of the 'conditions for existence' was introduced by Georges Cuvier in 1800, and provides a valid, conditional teleological method for explaining organismal structure and behavior. From an evolutionary perspective, the

  19. Estimated Tissue and Blood N(2) Levels and Risk of Decompression Sickness in Deep-, Intermediate-, and Shallow-Diving Toothed Whales during Exposure to Naval Sonar.

    PubMed

    Kvadsheim, P H; Miller, P J O; Tyack, P L; Sivle, L D; Lam, F P A; Fahlman, A

    2012-01-01

    Naval sonar has been accused of causing whale stranding by a mechanism which increases formation of tissue N(2) gas bubbles. Increased tissue and blood N(2) levels, and thereby increased risk of decompression sickness (DCS), is thought to result from changes in behavior or physiological responses during diving. Previous theoretical studies have used hypothetical sonar-induced changes in both behavior and physiology to model blood and tissue N(2) tension [Formula: see text], but this is the first attempt to estimate the changes during actual behavioral responses to sonar. We used an existing mathematical model to estimate blood and tissue N(2) tension [Formula: see text] from dive data recorded from sperm, killer, long-finned pilot, Blainville's beaked, and Cuvier's beaked whales before and during exposure to Low- (1-2 kHz) and Mid- (2-7 kHz) frequency active sonar. Our objectives were: (1) to determine if differences in dive behavior affects risk of bubble formation, and if (2) behavioral- or (3) physiological responses to sonar are plausible risk factors. Our results suggest that all species have natural high N(2) levels, with deep diving generally resulting in higher end-dive [Formula: see text] as compared with shallow diving. Sonar exposure caused some changes in dive behavior in both killer whales, pilot whales and beaked whales, but this did not lead to any increased risk of DCS. However, in three of eight exposure session with sperm whales, the animal changed to shallower diving, and in all these cases this seem to result in an increased risk of DCS, although risk was still within the normal risk range of this species. When a hypothetical removal of the normal dive response (bradycardia and peripheral vasoconstriction), was added to the behavioral response during model simulations, this led to an increased variance in the estimated end-dive N(2) levels, but no consistent change of risk. In conclusion, we cannot rule out the possibility that a combination

  20. Tracking marine mammals and ships with small and large-aperture hydrophone arrays

    NASA Astrophysics Data System (ADS)

    Gassmann, Martin

    Techniques for passive acoustic tracking in all three spatial dimensions of marine mammals and ships were developed for long-term acoustic datasets recorded continuously over months using custom-designed arrays of underwater microphones (hydrophones) with spacing ranging from meters to kilometers. From the three-dimensional tracks, the acoustical properties of toothed whales and ships, such as sound intensity and directionality, were estimated as they are needed for the passive acoustic abundance estimation of toothed whales and for a quantitative description of the contribution of ships to the underwater soundscape. In addition, the tracks of the toothed whales reveal their underwater movements and demonstrate the potential of the developed tracking techniques to investigate their natural behavior and responses to sound generated by human activity, such as from ships or military SONAR. To track the periodically emitted echolocation sounds of toothed whales in an acoustically refractive environment in the upper ocean, a propagation-model based technique was developed for a hydrophone array consisting of one vertical and two L-shaped subarrays deployed from the floating instrument platform R/P FLIP. The technique is illustrated by tracking a group of five shallow-diving killer whales showing coordinated behavior. The challenge of tracking the highly directional echolocation sounds of deep-diving (< 1 km) toothed whales, in particular Cuvier's beaked whales, was addressed by embedding volumetric small-aperture (≈ 1 m element spacing) arrays into a large-aperture (≈ 1 km element spacing) seafloor array to reduce the minimum number of required receivers from five to two. The capabilities of this technique are illustrated by tracking several groups of up to three individuals over time periods from 10 min to 33 min within an area of 20 km2 in the Southern California Bight. To track and measure the underwater radiated sound of ships, a frequency domain beamformer was

  1. [WILD MAMMALS OF THE GRAND DUCHY OF LITHUANIA IN THE WORKS OF JEAN-EMMANUEL GILIBERT].

    PubMed

    Samojlik, Tomasz; Daszkiewicz, Piotr

    2015-01-01

    Among the many topics of lively scientific work that Jean Emmanuel Gilibert (1741-1814) conducted in Grodno and Vilnius, an important place is occupied by his observations of wild mammals. Royal patronage and care from Antoni Tyzenhauz, Treasurer of the Grand Duchy of Lithuania and the governor of Grodno, allowed Gilibert to keep and observe wild fauna captured by royal services in royal forests, including Białowieża Primeval Forest. Such was an origin of a female bison kept by Gilibert in Grodno. Its description, published in Indagatores naturae in Lithuania (Vilnius 1781) for decades became the primary source of information about the behaviour, food preferences and the anatomy of European bison. European science has just begun to take interest in European bison, therefore Gilibert's account entered scientific circulation by way of French natural history encyclopaedias (mainly Georges Buffon's Histoire naturelle) and works by Georges Cuvier or Étienne Geoffroy Saint-Hilaire. Apart from the description of European bison, Gilibert left an entire series of observations of wild mammals inhabiting the forests of the Grand Duchy of Lithuania. His accounts of moose were important in building a knowledge base for this species. In the first half of the 18th century, moose was known mainly from fantastic descriptions in Renaissance works and from prescriptions devoted to using moose hoof as the epilepsy treatment. Gilibert's observations helped to overthrow such superstitions. Similarly, Gilibert's first-hand information verified the widespread legends concerning brown bear (e.g. the belief that white bears, belonging to other species than polar bears, occur in Lithuania) . List of species kept and thoroughly watched by the scholar is much longer and includes lynx, wolf (and hybrids of wolves and dogs), beaver, badger, fox, hedgehog, and even white mouse. Also his comments on the species of mammals then absent in Lithuania but known either from farming or from the fur

  2. [WILD MAMMALS OF THE GRAND DUCHY OF LITHUANIA IN THE WORKS OF JEAN-EMMANUEL GILIBERT].

    PubMed

    Samojlik, Tomasz; Daszkiewicz, Piotr

    2015-01-01

    Among the many topics of lively scientific work that Jean Emmanuel Gilibert (1741-1814) conducted in Grodno and Vilnius, an important place is occupied by his observations of wild mammals. Royal patronage and care from Antoni Tyzenhauz, Treasurer of the Grand Duchy of Lithuania and the governor of Grodno, allowed Gilibert to keep and observe wild fauna captured by royal services in royal forests, including Białowieża Primeval Forest. Such was an origin of a female bison kept by Gilibert in Grodno. Its description, published in Indagatores naturae in Lithuania (Vilnius 1781) for decades became the primary source of information about the behaviour, food preferences and the anatomy of European bison. European science has just begun to take interest in European bison, therefore Gilibert's account entered scientific circulation by way of French natural history encyclopaedias (mainly Georges Buffon's Histoire naturelle) and works by Georges Cuvier or Étienne Geoffroy Saint-Hilaire. Apart from the description of European bison, Gilibert left an entire series of observations of wild mammals inhabiting the forests of the Grand Duchy of Lithuania. His accounts of moose were important in building a knowledge base for this species. In the first half of the 18th century, moose was known mainly from fantastic descriptions in Renaissance works and from prescriptions devoted to using moose hoof as the epilepsy treatment. Gilibert's observations helped to overthrow such superstitions. Similarly, Gilibert's first-hand information verified the widespread legends concerning brown bear (e.g. the belief that white bears, belonging to other species than polar bears, occur in Lithuania) . List of species kept and thoroughly watched by the scholar is much longer and includes lynx, wolf (and hybrids of wolves and dogs), beaver, badger, fox, hedgehog, and even white mouse. Also his comments on the species of mammals then absent in Lithuania but known either from farming or from the fur

  3. A time-calibrated molecular phylogeny of the precious corals: reconciling discrepancies in the taxonomic classification and insights into their evolutionary history

    PubMed Central

    2012-01-01

    Background Seamount-associated faunas are often considered highly endemic but isolation and diversification processes leading to such endemism have been poorly documented at those depths. Likewise, species delimitation and phylogenetic studies in deep-sea organisms remain scarce, due to the difficulty in obtaining samples, and sometimes controversial. The phylogenetic relationships within the precious coral family Coralliidae remain largely unexplored and the monophyly of its two constituent genera, Corallium Cuvier and Paracorallium Bayer & Cairns, has not been resolved. As traditionally recognized, the diversity of colonial forms among the various species correlates with the diversity in shape of their supporting axis, but the phylogenetic significance of these characters remains to be tested. We thus used mitochondrial sequence data to evaluate the monophyly of Corallium and Paracorallium and the species boundaries for nearly all named taxa in the family. Species from across the coralliid range, including material from Antarctica, Hawaii, Japan, New Zealand, Taiwan, Tasmania, the eastern Pacific and the western Atlantic were examined. Results The concatenated analysis of five mitochondrial regions (COI, 16S rRNA, ND2, and ND3-ND6) recovered two major coralliid clades. One clade is composed of two subgroups, the first including Corallium rubrum, the type species of the genus, together with a small group of Paracorallium species (P. japonicum and P. tortuosum) and C. medea (clade I-A); the other subgroup includes a poorly-resolved assemblage of six Corallium species (C. abyssale, C. ducale, C. imperiale, C. laauense, C. niobe, and C. sulcatum; clade I-B). The second major clade is well resolved and includes species of Corallium and Paracorallium (C. elatius, C. kishinouyei, C. konojoi, C. niveum, C. secundum, Corallium sp., Paracorallium nix, Paracorallium thrinax and Paracorallium spp.). A traditional taxonomic study of this clade delineated 11 morphospecies that

  4. An attempt for understanding the history of the Istanbul Palaeozoic on a structural basis during the assembly of the Pangaea

    NASA Astrophysics Data System (ADS)

    Ülgen, Semih Can; Lom, Nalan; Özgül, Necdet; Sunal, Gürsel; Celãl Şengör, A. M.

    2014-05-01

    unlikely occurrence of much volume loss and strike-slip faulting along the orogen allow us to balance the cross-sections. By the help of two WNW-ESE detailed, 1:10,000-scale strip maps, two balanced-cross sections are currently under construction. The Istanbul Palaezoic sequence has been correlated on the stratigraphic basis with similar Hercynian zones in Europe in the past years. Despite these studies it is still controversial that the Istanbul Palaeozoic belongs to Gondwana or Laurasia. To solve these problems, correlation on structural basis and rewinding the deformation phases that Istanbul has suffered (post-Eocene, pre-Eocene and pre-Cretaceous) should be done. By detecting traces of these deformation phases and rewinding them, deformation story of the region will be revealed. By the help of these studies and application of Cuvier's law of correlation of parts, it will be determined where this part of "Hercynian Orogenic Belt" belongs to.