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1

Foraging success of juvenile pike Esox lucius depends on visual conditions and prey pigmentation.  

PubMed

Young-of-the-year pike Esox lucius foraging on copepods experienced different foraging success depending on prey pigmentation in water visually degraded by brown colouration or algae. Both attack rate and prey consumption rate were higher for E. lucius foraging on transparent prey in brown water, whereas the opposite was true in algal turbid water. Pigments in copepod prey may have a cryptic function in brown water instead of a photo-protective function even if prey-size selectivity was stronger than selection based on pigmentation in juvenile E. lucius. PMID:21722125

Jönsson, M; Hylander, S; Ranåker, L; Nilsson, P A; Brönmark, C

2011-07-01

2

Early life migration patterns of Baltic Sea pike Esox lucius.  

PubMed

This study investigated the movement patterns of Baltic Sea pike Esox lucius in Matsalu Bay, Estonia, using otolith microchemistry. Migration patterns of E. lucius were remarkably diverse, but distinct groups were evident. Of the E. lucius analysed (n = 28), 82% hatched in fresh water and 74% of them left this biotope during the first growth season. PMID:22471807

Rohtla, M; Vetemaa, M; Urtson, K; Soesoo, A

2012-04-01

3

Prey capture of pike Esox lucius larvae in turbid water.  

PubMed

Pike Esox lucius larvae captured fewer calanoid and cyclopoid copepods in turbid than in clear water, whereas no differences were detected in feeding rates on Daphnia longispina. Decreased capture of copepods may lead to lower growth and survival of E. lucius larvae in turbid areas, in particular, if cladocerans are scarce. PMID:20557612

Salonen, M; Engström-Ost, J

2010-06-01

4

Northern pike (Esox lucius) are common sport fish in the northern United States and Canada. In  

E-print Network

6 Northern pike (Esox lucius) are common sport fish in the northern United States and Canada Regulations in North America Northern pike (Esox lucius) is a popular sport fish in the United States, Madison, WI 53707-7921. Northern pike (Esox lucius) is a popular sport fish in the United States

5

MICROSATELLITE LETTERS EST-based microsatellites for northern pike (Esox lucius)  

E-print Network

MICROSATELLITE LETTERS EST-based microsatellites for northern pike (Esox lucius) and cross novel microsatellite markers in North American northern pike, Esox lucius, and tested cross out of 17 loci were successfully cross-amplified on all species. Keywords Esox lucius Á Northern pike

Bernatchez, Louis

6

Cytological identification of cell types in the testis of Esox lucius and E. niger  

Microsoft Academic Search

Testes of Esox lucius and Esox niger were investigated histologically, cytochemically, and ultrastructurally in reproductive fish. Intralobular Sertoli cells possessed numerous lipid droplets in Esox lucius, but not in Esox niger. In both species, interlobular cell types included myoid cells and lipid-negative Leydig cells within the extravascular space. Evidence is presented for a contractile network of myoid cells within the

H. J. Grier; R. Hurk; R. Billard

1989-01-01

7

Standard Weight Equation for Tiger Muskellunge (Esox lucius x Esox masquinongy)  

Microsoft Academic Search

Weight and length data for tiger muskellunge Esox lucius x Esox masquinongy were solicited from biologists across the continent to develop a 75th-percentile standard weight (Ws) equation for the hybrid. Only 27 populations (N = 1,124 fish) from 9 states yielded adequate data sets for this process. We used a bootstrap technique to demonstrate that the limited number of populations

Kevin B. Rogers; Keith D. Koupal

1997-01-01

8

Behaviour and survival of pike, Esox lucius, with a retained lure in the lower jaw  

E-print Network

Behaviour and survival of pike, Esox lucius, with a retained lure in the lower jaw R . A R L I N G The behaviour and survival of pike, Esox lucius L., released with a retained lure in the mouth was studied-and-release, fish welfare, lure, recreational fishing. Introduction Esocids such as muskellunge, Esox masquinongy

Cooke, Steven J.

9

L'organe pinal du Brochet (Esox lucius, L.). I. Etude anatomique et cytologique  

E-print Network

L'organe pinéal du Brochet (Esox lucius, L.). I. Etude anatomique et cytologique J. FALCON Pineau, 86022 Poitiers Cedex, France. Summary. The pineal organ of the pike, Esox lucius L., I. A light ; Plecoglossus : Omura et al.,1969 ; Omura et Oguri, 1971 ; Esox : Owman et Rüdeberg, 1970; Anguilla et Lebistes

Boyer, Edmond

10

L'organe pinal du Brochet (Esox lucius, L.) V. Etude radioautographique de l'incorporation in vivo  

E-print Network

L'organe pinéal du Brochet (Esox lucius, L.) V. Etude radioautographique de l'incorporation in vivo Poitiers Cedex, France. Summary. The pineal organ of the pike (Esox lucius, L.). V. Radioautographic study

Paris-Sud XI, Université de

11

Spatial behaviour of young-of-the-year northern pike (Esox lucius L.) in a temporarily flooded  

E-print Network

Spatial behaviour of young-of-the-year northern pike (Esox lucius L.) in a temporarily flooded nursery area Introduction Northern pike (Esox lucius L.) is a species particularly adapted to shallow of young-of-the-year northern pike (Esox lucius L.) in a temporarily flooded nursery area. Ecology

Cucherousset, Julien

12

L'organe pinal du Brochet (Esox lucius L.) III. Voies intrapinales de conduction  

E-print Network

; bipolar neurons were seen in the distal and proximal pineal. At the level of the subcommissural organL'organe pinéal du Brochet (Esox lucius L.) III. Voies intrapinéales de conduction des messages organ of the pike (Esox lucius, L.). II1. lntrapineal pathways for conduction of photosensory messages

Paris-Sud XI, Université de

13

Morphological study of the northern pike (Esox lucius) tongue.  

PubMed

The northern pike (Esox lucius) is a fresh water species belonging to the Esocidae family. It is a carnivorous fish feeding mostly on invertebrates and fishes. Due to the scantiness of relevant literature regarding the morphology of the tongue in fish we carried out this study with the aim of providing information on the dorsal surface morphology and histological structures of the tongue in E. lucius. The tongues of five E. lucius were examined using light- and scanning electron- microscopy (SEM) techniques. The SEM studies revealed the presence of numerous teeth, longitudinal mucosal strands and scattered taste buds spread on the tongue surface. Histological studies using hematoxylin and eosin and Masson's trichrome staining showed that the musculature was not visible in the tongue of E. lucius. The tongue is composed of mucosa, and submucosa supported by osteocartilagionous skeleton. The mucosa consists of several layers of unicellular mucous cells interrupted by numerous teeth. The derivation of teeth from the underlying bronchial skeleton was visible in longitudinal section. The scattered taste buds with a typical onion shape were also present. Overall, the morphological features of the E. lucius tongue together suggested its mechanical and sensory roles. The findings of this study together with morphological and physiological data from other fishes contribute to the knowledge of the nutrition and feeding behavior in aquaculture species. PMID:25205560

Sadeghinezhad, Javad; Rahmati-Holasoo, Hooman; Fayyaz, Sahel; Zargar, Ashkan

2014-09-10

14

Landscape variability explains spatial pattern of population structure of northern pike (Esox lucius) in a large fluvial  

E-print Network

-Foy, Quebec, Quebec G1S 4X4, Canada Keywords Conservation, environmental variation, Esox lucius, habitat. In this study, we document the landscape genetics of northern pike (Esox lucius), based on the analysisLandscape variability explains spatial pattern of population structure of northern pike (Esox

Bernatchez, Louis

15

Ovarian alterations in wild northern pike Esox lucius females.  

PubMed

The aim of the present study was to analyse the occurrence of macroscopically visible ovary alterations in 2 populations of northern pike Esox lucius L. originating from lakes in the Mazurian Lake District (NE Poland). The alterations were characterised by ovary tissue that was morphologically malformed, in part or in whole, and contained immature oocytes, i.e. trophoplastic or previtellogenic oocytes instead of vitellogenic oocytes. These alterations were found only in the ovaries, and no morphological alterations of the testes were noted. Macroscopic and histological analyses were carried out in order to classify the observed alterations in the ovaries. Three types of alterations were identified in which morphological malformations as well as histological investigation of the ovaries were considered. An analysis of the size and age of the fish in relation to the occurrence of alterations as well as of the macroscopic and histological nature of the alteration types was made. The data obtained revealed no lake or age dependency of the observed alterations. Based on the results obtained, we suggest that the presence of endocrine disruptors in the environment or/and genetic factors could be responsible for these kinds of gonad anomalies. However, our results did not allow us to determine the aetiology of the alterations. PMID:24062552

Zarski, Daniel; Rechulicz, Jacek; Krejszeff, S?awomir; Czarkowski, Tomasz K; Sta?czak, Katarzyna; Pali?ska, Katarzyna; Gryzi?ska, Magdalena; Targo?ska, Katarzyna; Koz?owski, Krzysztof; Mamcarz, Andrzej; Hliwa, Piotr

2013-09-24

16

Mercury elimination by a top predator, Esox lucius.  

PubMed

Top-level piscivores are highly sought after for consumption in freshwater fisheries, yet these species contain the highest levels of the neurotoxin monomethylmercury (MMHg) and therefore present the greatest concern for MMHg exposure to humans. The slow elimination of MMHg is one factor that contributes to high levels of this contaminant in fish; however, little quantitative information exists on elimination rates by top predators in nature. We determined rates of MMHg elimination in northern pike (Esox lucius) by transferring fish that had naturally accumulated isotope-enriched MMHg (spike MMHg) through a whole-lake Hg loading study to a different lake. Over a period of ~7 y, pike were periodically recaptured and a small amount of muscle tissue was extracted using a nonlethal biopsy. Spike total mercury (THg) persisted in muscle tissue throughout the entire study despite discontinuing exposure upon transfer to the new lake. Spike THg burdens increased for the first ~460 d, followed by a decline to 65% of original burden levels over the next 200 d, and subsequently reached a plateau near original burden levels for the remainder of the study. We estimated the half-life of muscle THg to be 3.3 y (1193 d), roughly 1.2- to 2.7-fold slower than predicted by current elimination models. We advocate for further long-term field studies that examine kinetics of MMHg in fish to better inform predictive models estimating the recovery of MMHg-contaminated fisheries. PMID:23566175

Van Walleghem, Jillian L A; Blanchfield, Paul J; Hrenchuk, Lee E; Hintelmann, Holger

2013-05-01

17

Habitat utilisation by pike Esox lucius L. during winter floods in a southern English chalk river  

Microsoft Academic Search

Seven pike Esox lucius L., implanted with radio-transmitters, were tracked throughout autumn and winter in the River Frome, a southern English chalk river. During the first flood events of the year, pike remained within the main river channel but during subsequent flood events, pike could also be found in flooded fields, in drainage ditches or in a millstream. Eighty percent

J. E. G. Masters; J. S. Welton; W. R. C. Beaumont; K. H. Hodder; A. C. Pinder; R. E. Gozlan; M. Ladle

2002-01-01

18

An experimental breakage of Reissner's fibre in the central canal of the pike ( Esox lucius )  

Microsoft Academic Search

Summary  The spinal cords of newly hatched pike (Esox lucius) fry were divided into two pieces by transverse cuts. After periods of different lengths, the appearances of the brokenReissner's fibres were investigated anatomically. The fibre normally terminates in the caudal end as a secretory accumulation, a caudal mass. After the operation this mass gradually disappears, apparently through the spinal cord wall

Ragnar Olsson

1957-01-01

19

Individual specialization and trophic adaptability of northern pike (Esox lucius): an isotope and dietary analysis  

Microsoft Academic Search

Northern pike (Esox lucius) are often considered to be specialist piscivores, but under some circumstances will continue to eat invertebrates as adults. To examine effects of fish assemblage composition on the trophic ecology of pike, we combined stable isotope analysis (SIA) of carbon and nitrogen and stomach content analysis (SCA) on pike from five lakes in northern Alberta, three of

Catherine P. Beaudoin; William M. Tonn; Ellie E. Prepas; Leonard I. Wassenaar

1999-01-01

20

Analysis of sibling cannibalism among pike, Esox lucius , juveniles reared under semi-natural conditions  

Microsoft Academic Search

Synopsis Sibling cannibalism in pike, Esox lucius, larvae and juveniles living in outdoor rearing ponds was studied using stomach contents analysis. For the two initial densities tested (6 and 18 larvae m?2, equivalent to 12 and 36 larvae m?3), cannibalism was non-existent during the larval period (13 to 35 mm total length) and was observed only during the juvenile stages.

Christian Bry; Edgar Basset; Xavier Rognon; François Bonamy

1992-01-01

21

Biomarkers of Contaminant Exposure in Northern Pike ( Esox lucius ) from the Yukon River Basin, Alaska  

Microsoft Academic Search

As part of a larger investigation, northern pike (n = 158; Esox lucius) were collected from ten sites in the Yukon River Basin (YRB), Alaska, to document biomarkers and their correlations with\\u000a organochlorine pesticide (total p,p’-DDT, total chlordane, dieldrin, and toxaphene), total polychlorinated biphenyls (PCBs), and elemental contaminant (arsenic,\\u000a cadmium, copper, lead, total mercury, selenium, and zinc) concentrations. A suite

J. E. Hinck; V. S. Blazer; N. D. Denslow; M. S. Myers; T. S. Gross; D. E. Tillitt

2007-01-01

22

General morphology and axonal ultrastructure of the olfactory nerve of the pike, Esox lucius  

Microsoft Academic Search

The olfactory nerve of the European pike (Esox lucius) contains 5.1 × 106 axons with an average diameter of 0.20 ± 0,04 µm and a length of 5.5 cm in 1 meter long pike. Each axon contains an average of 4 microtubules as well as neurofilaments, smooth endoplasmic reticulum and about 500 mitochondria per centimeter. The number of neurofilaments ranges

Georg W. Kreutzberg; Guenter W. Gross

1977-01-01

23

Mercury concentrations in northern pike, Esox lucius L., in small lakes of Evo area, southern Finland  

Microsoft Academic Search

We measured Hg concentrations in northern pike (Esox lucius) from 17 small lakes in Evo forest area, Lammi, southern Finland. The mean Hg concentration in muscle tissue of a 1 kg pike\\u000a ranged from 0.15 to 1.36 ?g g?1 (ww) in the lakes. There was a trend towards higher concentrations in acidic and humic lakes than in circumneutral and clear-water

M. Rask; T.-R. Metsälä

1991-01-01

24

THE MECHANICAL POWER OUTPUT AND HYDROMECHANICAL EFFICIENCY OF NORTHERN PIKE (ESOX LUCIUS) FAST-STARTS  

Microsoft Academic Search

The mechanical power output and hydrodynamic efficiency of northern pike, Esox lucius, during acceleration from rest (fast-start) are calculated from hydrodynamic theory for two kinematic patterns, C-starts (used in escape) and S-starts (used in prey capture). The Weihs model is employed and modified to calculate the mechanical power produced by a fish during a fast-start. A term is included for

H. RUSS FRITH; ROBERT W. BLAKE

25

New series of fatty acids in Northern Pike ( Esox lucius )  

Microsoft Academic Search

The presence in Northern Pike (Esox locius) liver and testes lipids of a group of eight homologous fatty acids of as yet unknown structure is reported. They occur esterified\\u000a to cholesterol and to glycerol as triglycerides but are absent from the phospholipids. They contain three oxygens and are\\u000a characterized further by being more resistant to hydrogenation than normal unsaturated fatty

R. L. Glass; Thomas P. Krick; Allen E. Eckhardt

1974-01-01

26

Rhipidocotyle fennica (Digenea: Bucephalidae) from Anodonta anatina and pike Esox lucius in Lithuania.  

PubMed

Ribosomal DNA sequences of Rhipidocotyle sp. adults from Esox lucius were shown to be identical to sequences of larval Rhipidocotyle fennica, occurring in Anodonta anatina in Lake Vilkokšnis, Lithuania. Morphological features and host specificity of this adult worm correspond with that, determinate in the first description of R. fennica in Finland. These data give the first evidence that a viable population of R. fennica exists in east central Europe. Bucephalus polymorphus which was reported in unionids in all previous publications is probably R. fennica. PMID:25190013

Stunž?nas, Virmantas; Petkevi?i?t?, Romualda; Stanevi?i?t?, Gražina; Binkien?, Rasa

2014-10-01

27

Genetic characterization of 18 novel microsatellite loci in northern pike (Esox lucius L.).  

PubMed

The northern pike (Esox lucius L.), an important predatory freshwater species, is undergoing significant population decline. In this study, 18 novel polymorphic microsatellite loci were isolated and used for assessing genetic variation in the Chinese Ulungur and Hungarian Balaton populations of the species. The number of alleles ranged from 2 to 13, observed heterozygosity from 0.154 to 0.920 and expected heterozygosity from 0.145 to 0.921, thereby indicating the specific usefulness of these suites of markers for investigating genetic variability. PMID:21637562

Wang, Jun; Wang, Chenghui; Qian, Long; Ma, Yuqing; Yang, Xinxin; Jeney, Zsigmond; Li, Sifa

2011-01-01

28

Physiological ecology of larval muskellunge and norlunge: temperature tolerance and growth rates under hatchery conditions. [Esox masquinongy, E. lucius  

Microsoft Academic Search

Critical Thermal Maxima (CTM) and growth rates of larval muskellunge (Esox masquinongy) and norlunge (E. masquinongy female x E. lucius male) were determined under hatchery conditions. Two groups of fish were maintained at ambient water temperatures with natural photoperiod. Weekly water samples were collected to monitor the troughs. Parameters measured were dissolved oxygen, pH, and ammonia which were within normal

Bonin

1976-01-01

29

Adrenergic neurons in the spinal cord of the pike ( Esox lucius ) and their relation to the caudal neurosecretory system  

Microsoft Academic Search

The lower spinal cord including the caudal neurosecretory system of the pike (Esox lucius) was investigated by means of light and electron microscopy and also with the fluorescence histochemical method of Falck and Hillarp for the visualization of monoamines. A system of perikarya displaying a specific green fluorescence of remarkably high intensity is disclosed in the basal part of the

H. G. Baumgarten; B. Falck; H. Wartenberg

1970-01-01

30

Dietary uptake in pike (Esox lucius) of some polychlorinated biphenyls, polychlorinated naphthalenes and polybrominated diphenyl ethers administered in natural diet  

Microsoft Academic Search

The dietary uptake of 12 halogenated diaromatic compounds was studied using northern pike (Esox lucius L.) fed with rainbow trout (Oncorhynchus mykiss (Walbaum)). Before the trout were fed to the pike, they had been injected with a cocktail of five polychlorinated biphenyls, four polychlorinated naphthalenes, and three polybrominated diphenyl ethers, dissolved in rainbow trout lipid. The reported uptake efficiencies (E)

Sven Burreau; Johan Axelman; Dag Broman; Eva Jakobsson

1997-01-01

31

The photosensory function of the pineal organ of the pike ( Esox lucius L.) Correlation between structure and function  

Microsoft Academic Search

Electrical recordings from the exposed pineal organ of the pike (Esox lucius L.) were performed in order to localize the photoreceptive structures. Extracellular recordings showed a maintained activity of nerve fibers from the pineal tract and of single neurons from the distal region of the pineal organ. At increasing levels of steady exposure to white light, the impulse frequency decreased.

Jacky Falcón; Hilmar Meissl

1981-01-01

32

The population dynamics of pike, Esox lucius , and perch, Perca fluviatilis , in a simple predator-prey system  

Microsoft Academic Search

The population dynamics and predator-prey relationship of pike, Esox lucius, and perch, Perca fluviatilis, were examined in simple fish communities in two adjacent shallow lakes, Lochs Kinord and Davan, Deeside, Scotland. Few perch survive to age 3 but Z is low for fish > 3 years and perch live up to 17 years. Population fecundity remained relatively high and constant

James W. Treasurer; Roger Owen; Eric Bowers

1992-01-01

33

A quantitative comparison between diet and body fatty acid composition in wild northern pike ( Esox lucius L.)  

Microsoft Academic Search

The fatty acid compositions of wild female northern pike (Esox lucius L.) and their principle prey species were compared to assess the extent to which pike modify the relative abundance of dietary fatty acids during assimilation and to indicate the optimum dietary content of essential fatty acids (EFAs) for pike. Only minor differences existed between the estimated whole body fatty

Karl Schwalmel

1992-01-01

34

Behavioral variation in pelvic phenotypes of brook stickleback, Culaea inconstans , in response to predation by northern pike, Esox lucius  

Microsoft Academic Search

Populations ofCulaea inconstans, from Alberta and Saskatchewan, Canada exhibit phenotypic variation in expression of the pelvic skeleton and associated spines, from complete presence (with) through intermediate forms to complete absence (without). Such variation influences predation byEsox lucius which prefer the least spiny prey. Behavioral differences were investigated before and during pike predation. These differences may be associated either with the

James D. Reist

1983-01-01

35

Mercury elimination rates for adult northern pike Esox lucius: evidence for a sex effect  

USGS Publications Warehouse

We examined the effect of sex on mercury elimination in fish by monitoring isotope-enriched mercury concentrations in the muscle tissue of three adult female and three adult male northern pike Esox lucius, which had accumulated the isotope-enriched mercury via a whole-lake manipulation and were subsequently moved to a clean lake. Mercury elimination rates for female and male northern pike were estimated to be 0.00034 and 0.00073 day?1, respectively. Thus, males were capable of eliminating mercury at more than double the rate than that of females. To the best of our knowledge, our study represents the first documentation of mercury elimination rates varying between the sexes of fish. This sex difference in elimination rates should be taken into account when comparing mercury accumulation between the sexes of fish from the same population. Further, our findings should eventually lead to an improved understanding of mechanisms responsible for mercury elimination in vertebrates.

Madenjian, Charles P.; Blanchfield, Paul J.; Hrenchuk, Lee E.; Van Walleghem, Jillian L. A.

2014-01-01

36

Mechanical suppression of northern pike (Esox lucius) populations in small Arizona reservoirs  

USGS Publications Warehouse

Introduced populations of northern pike Esox lucius have provided angling opportunities in the western United States (McMahon and Bennett 1996). However, the northern pike is a voracious piscivore and its large size, high fecundity, and broad physiological tolerance make it capable of drastically altering ecosystems it invades (Marchetti et al. 2004). Indeed, predation by northern pike has been shown to significantly alter fish community structure and put native fishes at a higher extinction risk (He and Kitchell 1990, Findlay et al. 2000). Predation by northern pike is viewed as a significant threat to native stocks of salmonids in Washington, British Columbia, and California (McMahon and Bennett 1996, California Department of Fish and Game [CDFG] 2003).

Kuzmenko, Yuliya; Spesiviy, Timofy; Bonar, Scott A.

2010-01-01

37

Biogenic amines formation in high-pressure processed pike flesh (Esox lucius) during storage.  

PubMed

The effects of vacuum packaging followed by high pressure processing on the shelf-life of fillets of pike (Esox lucius) were examined. Samples were pressure-treated at 300 and 500 MPa and stored at 3.5 and 12 °C for up to 70 days. The content of eight biogenic amines (putrescine, cadaverine, spermidine, spermine, histamine, tyramine, tryptamine and phenylethylamine) were determined. Putrescine showed very good correspondence with the level of applied pressure and organoleptic properties. Polyamines spermidine and spermine did not show statistically significant changes with the level of applied pressure and the time of storage. Increased cadaverine and tyramine contents were found in samples with good sensory signs, stored for longer time and/or kept at 12 °C, thus indicating the loss of freshness. Tryptamine and phenylethylamine were not detected in pressure-treated samples kept at 3.5 °C. Histamine was not detected in samples of good quality. PMID:24423558

K?ížek, Martin; Mat?jková, Kate?ina; Vácha, František; Dadáková, Eva

2014-05-15

38

Assessment of natal origin of pike ( Esox lucius ) in the Baltic Sea using Sr:Ca in otoliths  

Microsoft Academic Search

Spawning habitat of pike (Esox lucius) in the Baltic Sea include brackish water bays, brooks and rivers. Elevated salinity concentrations are one of several stressors\\u000a that might increase the use and importance of freshwater habitats for spawning. In the Baltic Sea, one of the largest brackish\\u000a seas in the world, freshwater species like pike, perch (Perca fluviatilis), whitefish (Coregonus sp),

Olof Engstedt; Patrik Stenroth; Per Larsson; Lars Ljunggren; Mikael Elfman

2010-01-01

39

The desaturation and elongation of 14 C-labelled polyunsaturated fatty acids by pike ( Esox lucius L.) in vivo  

Microsoft Academic Search

To examine the ability of pike (Esox lucius L.) to modify exogenous PUFA by desaturation and elongation, 14C-labelled 18:2(n-6), 18:3(n-3), 20:4(n-6) and 20:5(n-3) were injected intraperitoneally and the distribution of radioactivity in tissue lipid classes and liver PUFA measured. In all tissues examined, radioactivity from all 14C-PUFA was recovered in many classes of acyl lipids and the level of recovery

R. James Henderson; Moira T. Park; John R. Sargent

1995-01-01

40

Susceptibility of pike Esox lucius to a panel of Ranavirus isolates.  

PubMed

In order to study the pathogenicity of ranaviruses to a wild European freshwater fish species, pike Esox lucius fry were challenged with the following Ranavirus isolates: epizootic haematopoietic necrosis virus (EHNV), European sheatfish virus (ESV), European catfish virus (ECV), pike-perch iridovirus (PPIV), New Zealand eel virus (NZeelV) and frog virus 3 (FV3). The fry were infected using bath challenge at 12 and 22 degrees C. Significant mortalities were observed at 12 degrees C for EHNV, ESV, PPIV and NZeelV. Background mortality was too high in the experiments performed at 22 degrees C for any conclusions about viral pathogenicity at this temperature to be drawn. Viruses could be re-isolated from samples from all challenged groups, and their presence in infected tissue was demonstrated using immunohistochemistry. The findings suggest that pike fry are susceptible to EHNV, ESV, PPIV and NZeelV and can be a vector for ECV and FV3. Statistical analysis of the factors associated with positive virus re-isolation showed that the number of fish in the sample influenced the outcome of virus re-isolation. Moreover, the likelihood of positive virus re-isolation significantly differed among the 6 viral isolates. The temperature from where the sample was taken and the number of days after infection were not associated with the probability of a positive virus re-isolation. PMID:19402450

Jensen, Britt Bang; Ersbøll, Annette Kjaer; Ariel, Ellen

2009-02-25

41

Temporal change estimation of mercury concentrations in northern pike (Esox lucius L.) in Swedish lakes.  

PubMed

Adequate temporal trend analysis of mercury (Hg) in freshwater ecosystems is critical to evaluate if actions from the human society have affected Hg concentrations ([Hg]) in fresh water biota. This study examined temporal change in [Hg] in Northern pike (Esox lucius L.) in Swedish freshwater lakes between 1994 and 2006. To achieve this were lake-specific, multiple-linear-regression models used to estimate pike [Hg], including indicator variables representing time and fish weight and their interactions. This approach permitted estimation of the direction and magnitude of temporal changes in 25 lakes selected from the Swedish national database on Hg in freshwater biota. A significant increase was found in 36% of the studied lakes with an average increase in pike [Hg] of 3.7±6.7% per year that was found to be positively correlated with total organic carbon. For lakes with a significant temporal change the dataset was based on a mean of 30 fish, while for lakes with no temporal change it was based on a mean of 13 fish. PMID:22014468

Åkerblom, Staffan; Nilsson, Mats; Yu, Jun; Ranneby, Bo; Johansson, Kjell

2012-02-01

42

Visibility conditions and diel period affect small-scale spatio-temporal behaviour of pike Esox lucius in the absence of prey and conspecifics.  

PubMed

Pike Esox lucius in the absence of prey and conspecifics were shown to have the highest habitat-change activity during dusk and to decrease preference for complex habitats in turbid water. As the behaviours indicate routine responses in the absence of behavioural interactions, E. lucius spatio-temporal distributions should be directly affected and thereby more easily assessed and avoided by prey, with potential consequences for encounter rates. PMID:22551189

Nilsson, P A; Baktoft, H; Boel, M; Meier, K; Jacobsen, L; Rokkjaer, E M; Clausen, T; Skov, C

2012-05-01

43

Larval deformities associated with selenium accumulation in northern pike (Esox lucius) exposed to metal mining effluent.  

PubMed

The objective of this study was to investigate selenium toxicosis in larval northern pike (Esox lucius) originating from reproductively mature pike collected downstream of a uranium milling operation in northern Saskatchewan, Canada. Eggs were obtained from female pike collected from a reference site and three sites representing an exposure gradient (approximately 2, 10, and 15 km downstream of effluent discharge). Embryos were incubated following a two-way (crossover) analysis of variance experimental design that allowed discrimination between effects due to maternal transfer to eggs and effects due to site water exposure in the developing embryos. The major finding of this study was a significant increase in the frequencies of individual deformities (skeletal curvatures, craniofacial deformities, and fin deformities) and edema in fry originating from high and medium exposure site females (mean selenium concentrations of 48.23 and 31.28 microg/g egg dry weight and 38.27 and 16.58 microg/g muscle dry weight, respectively) compared to reference site females. Selenium concentrations resulting in a 20% increase in total deformities above background levels (EC20S) were 33.55 and 21.54 micro/g dry weight in eggs and muscle, respectively. Mathematical conversion of the egg- and muscle-derived relationships to whole body selenium levels resulted in similar EC20S of 15.56 and 17.72 microg/g dry weight, respectively. These relationships between tissue selenium levels and larval deformities suggest that northern pike are within the same range of sensitivity to selenium as the majority of warm water (e.g., centrarchids and cyprinids) and cold water (e.g., salmonids) fish species studied to date. PMID:17120587

Muscatello, Jorgelina R; Bennett, Pamela M; Himbeault, Kevin T; Belknap, Andrew M; Janz, David M

2006-10-15

44

Light, fluorescence, and electron microscopic studies on the pineal organ of the pike, Esox lucius L., with special regard to 5-hydroxytryptamine  

Microsoft Academic Search

The pineal organ of adult pikes, Esox lucius L., maintained under normal diurnal conditions, was studied with a combination of light microscopy, fluorescence histochemistry of certain arylethylamines, and electron microscopy.1.The pineal parenchyma consists of sensory cells, supporting cells, and a third cell type which may be identical with previously described ganglion cells. The nerve fibres constituting the pineal tract were

Christer Owman; Claes Rüdeberg

1970-01-01

45

Bioenergetics and growth of young-of the-year northern pike ( Esox lucius) and burbot ( Lota lota) exposed to metal mining effluent  

Microsoft Academic Search

We hypothesized that exposure to metal mining effluent would reduce the ability of young-of-the-year fishes to accumulate energy reserves to survive the overwinter period (known as “winter stress syndrome”) in a Canadian boreal forest watershed. Northern pike (Esox lucius) and burbot (Lota lota) were collected immediately before and after winter from a reference lake and two lakes receiving effluent. Unexpectedly,

Pamela M. Bennett; David M. Janz

2007-01-01

46

Biomarkers of contaminant exposure in Northern Pike (Esox lucius) from the Yukon River Basin, Alaska.  

PubMed

As part of a larger investigation, northern pike (n = 158; Esox lucius) were collected from ten sites in the Yukon River Basin (YRB), Alaska, to document biomarkers and their correlations with organochlorine pesticide (total p,p'-DDT, total chlordane, dieldrin, and toxaphene), total polychlorinated biphenyls (PCBs), and elemental contaminant (arsenic, cadmium, copper, lead, total mercury, selenium, and zinc) concentrations. A suite of biomarkers including somatic indices, hepatic 7-ethoxyresorufin O-deethylase (EROD) activity, vitellogenin concentrations, steroid hormone (17B- ustradiol and 16-kebtestosteront) concentrations, splenic macrophage aggregates (MAs), oocyte atresia, and other microscopic anomalies in various tissues were documented in YRB pike. Mean condition factor (0.50 to 0.68), hepatosomatic index (1.00% to 3.56%), and splenosomatic index (0.09% to 0.18%) were not anomalous at any site nor correlated with any contaminant concentration. Mean EROD activity (0.71 to 17.51 pmol/min/mg protein) was similar to basal activity levels previously measured in pike and was positively correlated with selenium concentrations (r = 0.88, P < 0.01). Vitellogenin concentrations in female (0.09 to 5.32 mg/mL) and male (<0.0005 to 0.097 mg/mL) pike were not correlated with any contaminant, but vitellogenin concentrations >0.01 mg/mL in male pike from multiple sites indicated exposure to estrogenic compounds. Mean steroid hormone concentrations and percent oocyte atresia were not anomalous in pike from any YRB site. Few site differences were significant for mean MA density (1.86 to 6.42 MA/mm(2)), size (812 to 1481 microm(2)), and tissue occupied (MA-%; 0.24% to 0.75%). A linear regression between MA-% and total PCBs was significant, although PCB concentrations were generally low in YRB pike (< or =63 ng/g), and MA-% values in female pike (0.24% to 0.54%) were lower than in male pike (0.32% to 0.75%) at similar PCB concentrations. Greater numbers of MAs were found as zinc concentrations increased in YRB female pike, but it is unlikely that this is a causative relationship. Histological abnormalities observed in gill, liver, spleen, and kidney tissues were not likely a result of contaminant exposure but provide information on the general health of YRB pike. The most common histologic anomalies were parasitic infestations in various organs and developing nephrons and nephrocalcinosis in posterior kidney tissues. Overall, few biomarker responses in YRB pike were correlated with chemical contaminant concentrations, and YRB pike generally appeared to be healthy with no site having multiple anomalous biomarker responses. PMID:17396212

Hinck, J E; Blazer, V S; Denslow, N D; Myers, M S; Gross, T S; Tillitt, D E

2007-05-01

47

Changes in mercury levels in lake whitefish ( Coregonus clupeaformis ) and northern pike ( Esox lucius ) in the LG2 reservoir since flooding  

Microsoft Academic Search

After flooding of the LG-2 reservoir in 1978–1979, it was noticed that Hg levels in fish rose dramatically. In this study the Hg data have been examined on the basis of fish age for lake whitefish (Coregonus clupeaformis) and northern pike (Esox lucius), representing two different trophic levels. Data were fit to Von Bertalanffy functions using non-linear regression analyses. Reductions

K. A. Morrison; N. Thérien

1995-01-01

48

Side-aspect target strength of Atlantic salmon ( Salmo salar ), brown trout ( Salmo trutta ), whitefish ( Coregonus lavaretus ), and pike ( Esox lucius )  

Microsoft Academic Search

The side-aspect acoustic target strengths (TS) of 19 Atlantic salmons (Salmo salar), 16 brown trouts (Salmo trutta), 10 whitefish (Coregonus lavaretus) and 9 pikes (Esox lucius) were measured using a 200 kHz split-beam echosounder, in order to study the relationship between TS and fish size indices (length, weight and side area). The effect of side aspect angle on TS was also

Juha Lilja; Timo J Marjomäki; Raimo Riikonen; Juha Jurvelius

2000-01-01

49

The mast cell nature of granule cells in the digestive tract of the pike, Esox lucius : similarity to mammalian mucosal mast cells and globule leucocytes  

Microsoft Academic Search

Observations were made on sections of intestinal tissue from the pike,Esox lucius, fixed in a solution containing 4% formaldehyde and 5% acetic acid in methanol. Four staining procedures, using May-Grünwald Giemsa combi-nation dye, hematoxylin and eosin, toluidine blue, and alcian blue in sequence with safranin, were applied. Numerous granule cells were found in the area of stratum compactum and in

OLA B. REITE

1996-01-01

50

[Taxonomic characteristics and physiological properties of microorganisms from the gut of pike (Esox lucius)].  

PubMed

The taxonomic composition and distribution of microorganisms differing in the degree of association with the intestinal mucosa of the pike (Lucius lucius) has been studied. Microorgansism of the families Enterobacteriaceae, Aeromonadaceae, and Vibrionaceae dominate in the gut microflora. Numerically prevailing bacterial species are characterized by high proteolytic and amylolytic enzyme activities as well as by high persistence accounted for by antilysozyme and antihistone activities. The results of this study show that Hafnia alvei, Yersinia ruckeri, Vibrio vulnificus, V. furnissii, Aeromonas salmonicida, and Shewanella putrefaciens may be regarded as normal components of the pike gut microflora. PMID:19198074

Izveskova, G I; Nemtseva, N V; Plotnikov, A O

2008-01-01

51

Fish Community Responses to the Establishment of a Piscivore, Northern Pike (Esox lucius), in a Nebraska Sandhill Lake  

USGS Publications Warehouse

Northern pike (Esox lucius) was first documented in West Long Lake, Nebraska, in 1998 when two pike <380 mm were collected. In 2002, a Peterson mark-recapture population estimate on northern pike revealed density and standing stock (i.e., biomass) estimates of 35.8 fish/ha (95% CI= ?? 8.8) and 22.0 kg/ha (95% CI= ?? 5.4), respectively. Consequently, West Long Lake was sampled in 2002 to compare relative abundance, size structure, and growth of bluegill (Lepomis macrochirus), largemouth bass (Micropterus salmoides), and yellow perch (Perca flavescens) prior to and after the establishment of a high-density northern pike population. Bluegill, largemouth bass, and yellow perch relative abundances were significantly lower in 2002 than 1998. Similarly, size structures of all three species were significantly different between years. Size structure declined for both bluegill and yellow perch, and increased for largemouth bass. Growth was significantly higher for bluegill, largemouth bass, and yellow perch in 2002 than 1998. While the fish community changes were expected with the establishment of northern pike, they occurred in a relatively short time period (i.e., four years).

DeBates, T.J.; Paukert, C.P.; Willis, D.W.

2003-01-01

52

Between-population similarity in intestinal parasite community structure of pike (Esox lucius)--effects of distance and historical connections.  

PubMed

The effect of geographical distance on similarity in parasite communities of freshwater fish has received considerable attention in recent years, and it has become evident that these apparently simple relationships are influenced by, among other things, colonization ability of parasites and degree of connectivity between the populations. In the present paper, we explored qualitative and quantitative similarity in the intestinal parasite communities of pike (Esox lucius) in a particular system where previously interconnected groups of lakes became isolated ca. 8,400 yr ago. Contrary to our expectations, we did not find differences in similarity between the lake groups or a negative effect of distance among the populations. This supports the role of common ancestral colonization events and shows that no significant loss of species has occurred during the past 8,000 yr. However, the communities were dominated by a single parasite species, the cestode Triaenophorus nodulosus. The exclusion of this species from the data had a significant negative impact on the community similarities and also revealed a negative relationship between distance and quantitative similarity. This suggests that patterns of community organization may be obscured by a single dominant species. We also highlight the need for further studies in different systems and host species, as well as detailed reanalysis of existing data sets, to unravel the controversy in the relationship between distance and similarity in parasite communities. PMID:18925789

Karvonen, Anssi; Valtonen, E Tellervo

2009-06-01

53

{sup 32}P-postlabeling analysis of DNA adducts in wild perch (Perca fluviatilis) and northern pike (Esox lucius)  

SciTech Connect

Several previous studies have demonstrated a correlation between high concentrations of sediment-associated contaminants and elevated levels of aromatic/hydrophobic DNA adduct levels in the liver of benthic fish species. In the present study DNA adducts was analyzed in coastal populations of perch (Perca fluviatilis) and northern pike (Esox lucius). Fish were sampled from four different sites in a gradient from a heavily industrialized area at the Swedish Baltic coast. For comparison, fish were also caught in a reference area with no main industries and comparatively low levels of contaminants of anthropogenic origin. DNA was extracted from liver and several extrahepatic tissues and DNA adducts were analyzed by the nuclease PI version of the {sup 32}P-postlabeling assay. The autoradiograms derived from DNA of fish from the contaminated sites showed several adduct spots not visible on the autoradiograms derived from fish from the reference area. Total adduct levels were significantly elevated in several tissues in fish from contaminated sites compared to the reference area. Species and tissue-specific differences in adduct levels and the use of {sup 32}P-postlabeling analysis of DNA adducts as a biomarker to monitor the presence and effects of genotoxic chemicals in the aquatic environment are discussed.

Ericson, G.; Liewenborg, B.; Balk, L. [Stockholm Univ., Nykoeping (Sweden)

1995-12-31

54

Dietary uptake in pike (Esox lucius) of some polychlorinated biphenyls, polychlorinated naphthalenes and polybrominated diphenyl ethers administered in natural diet  

SciTech Connect

The dietary uptake of 12 halogenated diaromatic compounds was studied using northern pike (Esox lucius L.) fed with rainbow trout (Oncorhynchus mykiss (Walbaum)). Before the trout were fed to the pike, they had been injected with a cocktail of five polychlorinated biphenyls, four polychlorinated naphthalenes, and three polybrominated diphenyl ethers, dissolved in rainbow trout lipid. The reported uptake efficiencies (E) were in the range 35 to 90% and differ in some respect from earlier studies. The E-values for those substances with effective cross sections (ECS) >9.5 {angstrom} were considerably higher than expected if the membrane permeation at dietary uptake was restricted as proposed previously in the literature. There was no hydrophobicity dependency of the total dietary uptake efficiency as suggested by an earlier proposed empirical model. The difference between the results presented here and earlier studies is likely to depend on cotransport with lipids and/or proteins through a mediated, possibly active uptake of hydrophobic organic compounds (HOC) in the gastrointestinal tract enabled by the actual exposure method. For the proposed mediated/active uptake of HOCs, the uptake efficiency varied with molecular weight and was greatest for a molecular weight of approximately 450.

Burreau, S.; Axelman, J.; Broman, D.; Jakobsson, E. [Stockholm Univ. (Sweden)

1997-12-01

55

Induction of gene responses in St. Lawrence River northern pike (Esox lucius) environmentally exposed to perfluorinated compounds.  

PubMed

Municipal waste water effluents (MWWEs) are important sources of chemical contamination for aquatic environments. This study investigated the presence and effects of perfluorinated compounds (PFCs) in environmentally exposed northern pike (Esox lucius) collected upstream and downstream a major municipal waste water treatment plant (WWTP) in the St. Lawrence River, Canada. Twelve PFCs, including the newly detected perfluoroethylcyclohexane sulfonate (PFECHS), were quantified in fish muscle, liver, and plasma. Additionally, the expression of eight genes and the activity of three biomarkers were analyzed in fish tissues at both sites. Mean ?PFC concentration in fish plasma collected upstream the WWTP was 185ng/g w.w. compared to 545ng/g w.w. downstream the point of release. PFECHS was quantified for the first time in St. Lawrence River fish (mean plasma concentration in MWWE fish: 5.07±4.72ng/g w.w.). Results of transcriptomic responses were tissue-specific and indicated significant up-regulation for metallothionein (MT) in blood and MT, glutathion-S-transferase (GST), superoxide dismutase (SOD), and cytochromes P450 1A1 (CYP1A1) in gill tissue of fish collected in the MWWE suggesting greater stress responses for organisms at this location. Significant relationships were found between vitellogenin (Vtg) gene expression in liver, Vtg activity in plasma and perfluorotridecanoic acid (PFTrA), perfluorotetradecanoic acid (PFTeA), and perfluorodecane sulfonate (PFDS) plasma concentrations. The possible endocrine effects of these PFCs should be further investigated. PMID:23453599

Houde, Magali; Douville, Mélanie; Despatie, Simon-Pierre; De Silva, Amila O; Spencer, Christine

2013-08-01

56

Spatial analysis of Cd and Pb in the Pike (Esox lucius) from Western Anzali wetlands of Iran.  

PubMed

Geostatistical studies are used to estimate pollution burden in aquatic ecosystems and to plan large-scale control programs to protect these environments. Geostatistical studies allow us to predicted pollutant concentrations for areas that have not been sampled. This is done by taking into account the spatial correlations between estimated and sampled points and by minimizing the variance of estimation error. The use of geostatistical techniques in biomonitoring of fish species can illuminate extent and source of pollution, thereby providing an effective tool for developing intervention strategies to protect such environments. This study investigates the spatial distribution patterns of cadmium and lead in the Pike (Esox lucius). Fish were captured in the western parts of the Anzali wetlands located on the Caspian Sea in Iran. The muscle tissue of Anzali Pike had 5 ± 0.25 and 168 ± 18.4 (ng/g dw) cadmium and lead, respectively. Positive relationships were detected between Pike's length and weight (r = 0.85, p < 0.05), length and age (r = 0.35, p < 0.05), and muscle cadmium and lead (r = 0.45, p < 0.05). By contrast, there was a negative relationship between lead levels and weight in Pike (r = -0.36, p < 0.05). For both metals, the resulting metal concentration maps indicated higher pollutant concentrations in the southeast parts of the study area. Considerable boat traffic activity and agricultural activity contribute to the pollution in these areas, undermining the integrity of local habitat for fish survival and reproduction. PMID:23292487

Zamani-Ahmadmahmoodi, R; Esmaili-Sari, A; Mohammadi, J; Riyahi Bakhtiari, A; Savabieasfahani, M

2013-04-01

57

Assessment of oxidative stress and histopathology in juvenile northern pike (Esox lucius) inhabiting lakes downstream of a uranium mill.  

PubMed

Lakes receiving effluent from the Key Lake uranium mill in northern Saskatchewan contain elevated trace metals, some of which are associated with increased reactive oxygen species (ROS) in cells and tissues causing oxidative stress. The potential for oxidative stress was assessed in juvenile (age 1+) northern pike (Esox lucius) collected from two exposure (high and low) and one reference lake near the Key Lake operation. The concentrations of total, reduced and oxidized glutathione and the ratio of oxidized to reduced glutathione in liver and kidney did not differ significantly among pike collected from exposure and reference lakes, with the exception of low exposure pike kidney that had significantly greater oxidized glutathione and ratio of oxidized to reduced glutathione. The concentrations of by-products of lipid peroxidation (malondialdehyde and 4-hydroxyalkenal) were significantly greater in kidney of pike collected from the reference lake compared to both exposure lakes. The activity of the antioxidant enzyme glutathione peroxidase in liver was greater in pike collected from the high exposure lake compared to the reference lake. Histopathological evaluations revealed greater pathology in reference lake pike as indicated by a greater number of pyknotic and fragmented nuclei and dilated tubules as well as a thickening of Bowman's capsule in kidney, and as a thickening of the primary filament epithelial padding in gills. In liver, hepatocyte morphology, including transsectional area and degree of vacuolation, differed among lakes without any clear signs of pathology. Trace metal analyses of muscle showed that eight elements (arsenic, cobalt, copper, iron, molybdenum, selenium, thallium, and uranium) were significantly elevated in pike collected from both exposure lakes compared to reference. These results provide only limited evidence of oxidative stress in exposure pike tissues and no evidence of histopathology despite indications that trace metals, most notably arsenic and selenium, were bioaccumulating in tissue. PMID:19304330

Kelly, Jocelyn M; Janz, David M

2009-05-17

58

Landscape variability explains spatial pattern of population structure of northern pike (Esox lucius) in a large fluvial system  

PubMed Central

A growing number of studies have been investigating the influence of contemporary environmental factors on population genetic structure, but few have addressed the issue of spatial patterns in the variable intensity of factors influencing the extent of population structure, and particularly so in aquatic ecosystems. In this study, we document the landscape genetics of northern pike (Esox lucius), based on the analysis of nearly 3000 individuals from 40 sampling sites using 22 microsatellites along the Lake Ontario – St. Lawrence River system (750 km) that locally presents diverse degrees of interannual water level variation. Genetic structure was globally very weak (FST = 0.0208) but spatially variable with mean level of differentiation in the upstream section of the studied area being threefold higher (FST = 0.0297) than observed in the downstream sector (FST = 0.0100). Beside interannual water level fluctuation, 19 additional variables were considered and a multiple regression on distance matrices model (R2 = 0.6397, P < 0.001) revealed that water masses (b = 0.3617, P < 0.001) and man-made dams (b = 0.4852, P < 0.005) reduced genetic connectivity. Local level of interannual water level stability was positively associated to the extent of genetic differentiation (b = 0.3499, P < 0.05). As water level variation impacts on yearly quality and localization of spawning habitats, our study illustrates how temporal variation in local habitat availability, caused by interannual water level fluctuations, may locally decrease population genetic structure by forcing fish to move over longer distances to find suitable habitat. This study thus represents one of the rare examples of how environmental fluctuations may influence spatial variation in the extent of population genetic structure within a given species.

Ouellet-Cauchon, Geneviève; Mingelbier, Marc; Lecomte, Frédéric; Bernatchez, Louis

2014-01-01

59

Effects of osmolality on sperm morphology, motility and flagellar wave parameters in Northern pike (Esox lucius L.).  

PubMed

Northern pike (Esox lucius L.) spermatozoa are uniflagellated cells differentiated into a head without acrosome, a midpiece and a flagellar tail region flanked by a fin structure. Total, flagellar, head and midpiece lengths of spermatozoa were measured and show mean values of 34.5, 32.0, 1.32, 1.17 microm, respectively, with anterior and posterior widths of the midpiece measuring 0.8 and 0.6 microm, respectively. The osmolality of seminal plasma ranged from 228 to 350 mOsmol kg(-1) (average: 283.88+/-33.05). After triggering of sperm motility in very low osmolality medium (distilled water), blebs appeared along the flagellum. At later periods in the motility phase, the tip of the flagellum became curled into a loop shape which resulted in a shortening of the flagellum and a restriction of wave development to the proximal part (close to head). Spermatozoa velocity and percentage of motile spermatozoa decreased rapidly as a function of time postactivation and depended on the osmolality of activation media (P<0.05). In general, the greatest percentage of motile spermatozoa and highest spermatozoa velocity were observed between 125 and 235 mOsmol kg(-1). Osmolality above 375 mOsmol kg(-1) inhibited the motility of spermatozoa. After triggering of sperm motility in activation media, beating waves propagated along the full length of flagella, while waves appeared dampened during later periods in the motility phase, and were absent at the end of the motility phase. By increasing osmolality, the velocity of spermatozoa reached the highest value while wave length, amplitude, number of waves and curvatures also were at their highest values. This study showed that sperm morphology can be used for fish classification. Sperm morphology, in particular, the flagellar part showed several changes during activation in distilled water. Sperm motility of pike is inhibited due to high osmolality in the seminal plasma. Osmolality of activation medium affects the percentage of motile sperm and spermatozoa velocity due to changes in flagellar wave parameters. PMID:19269024

Alavi, S M Hadi; Rodina, Marek; Viveiros, Ana T M; Cosson, Jacky; Gela, David; Boryshpolets, Sergei; Linhart, Otomar

2009-07-01

60

Investigation of first year biotic and abiotic influences on the recruitment of pike Esox lucius over 48 years in Windermere, UK.  

PubMed

Estimated pike Esox lucius recruitment varied by a factor of 16 for females from 1944 to 1991 and by a factor of 27 for males from 1943 to 1990 in Windermere, a temperate, mesotrophic U.K. lake. No significant stock-recruitment relationships were found, but analysis with general additive models (GAMs) revealed that early autumnal water temperature, strength and direction of the North Atlantic Oscillation displacement (corresponding to different climatic conditions in winter) and zooplankton abundance but above all, late summer water temperature were important explanatory variables over the entire time series. Female recruitment was also influenced by young-of-the-year winter temperature. There was no evidence that perch Perca fluviatilis year-class strength, lake level or the summer position of the Gulf Stream influenced recruitment. The fitted models explained up to c. 65% of the overall observed variation between years. PMID:20735553

Paxton, C G M; Winfield, I J; Fletcher, J M; George, D G; Hewitt, D P

2009-07-01

61

Environmental factors regulate the effects of roach Rutilus rutilus and pike Esox lucius on perch Perca fluviatilis populations in small boreal forest lakes.  

PubMed

In this study of 18 small boreal forest lakes, the effects of abiotic and biotic factors (roach Rutilus rutilus and pike Esox lucius) on various population variables of perch Perca fluviatilis were examined. As a single variable, the gillnet catch per unit effort (CPUE) of R. rutilus was negatively related to the mean mass of small (< 200 mm) and the growth rate of young (1-2 years) P. fluviatilis. The mean mass of large (> or = 200 mm) P. fluviatilis was the highest at intermediate CPUE of R. rutilus. Redundancy analysis including environmental factors and P. fluviatilis population variables suggested that 'predation-productivity-humus' gradient affected P. fluviatilis populations by decreasing the CPUE and mean mass of small individuals but increasing these variables of large individuals. The CPUE of R. rutilus and lake area had a negative effect on small and a positive effect on large P. fluviatilis growth rate. In small boreal forest lakes, P. fluviatilis populations are affected by the partially opposite forces of competition by R. rutilus and predation by E. lucius, and the intensity of these interactions is regulated by several environmental factors. PMID:20537014

Olin, M; Vinni, M; Lehtonen, H; Rask, M; Ruuhijärvi, J; Saulamo, K; Ala-Opas, P

2010-04-01

62

Uptake and distribution of (/sup 3/H)benzo(a)pyrene in the Northern pike (Esox lucius). Examination by whole-body autoradiography and scintillation counting  

SciTech Connect

The uptake and distribution of the polyaromatic hydrocarbon benzo(a)pyrene in Northern pike (Esox lucius) were investigated by whole body autoradiography and scintillation counting. (/sup 3/H)Benzo(a)pyrene was administered either in the diet or in the water. The uptake and distribution of this compound and its metabolites were followed from 10 hr to 21 days after the initial exposure. The autoradiography patterns observed here with both routes of administration suggest, as expected, that benzo(a)pyrene is taken up through the gastrointestinal system and the gills, metabolized in the liver, and excreted in the urine and bile. Other findings indicate that the gills may not be a major route of excretion for benzo(a)pyrene and its metabolites in the Northern pike; that benzo(a)pyrene may be taken up from the water directly into the skin of this fish; that benzo(a)pyrene and its metabolites are heterogeneously distributed in the kidney of the Northern pike; and that very little radioactivity accumulates in the adipose tissue. With scintillation counting, uptake of radioactivity from the water was found to occur rapidly in all organs, reaching a plateau in most cases after about 0.8 days. The concentrations of radioactivity in different organs ranged between 50 (many organs) and 80,000 (gallbladder + bile) times that found in the surrounding water.

Balk, L.; Meijer, J.; DePierre, J.W.; Appelgren, L.E.

1984-07-01

63

Bioenergetics and growth of young-of the-year northern pike (Esox lucius) and burbot (Lota lota) exposed to metal mining effluent.  

PubMed

We hypothesized that exposure to metal mining effluent would reduce the ability of young-of-the-year fishes to accumulate energy reserves to survive the overwinter period (known as "winter stress syndrome") in a Canadian boreal forest watershed. Northern pike (Esox lucius) and burbot (Lota lota) were collected immediately before and after winter from a reference lake and two lakes receiving effluent. Unexpectedly, total body lipid and triglyceride, and liver triglyceride levels were greater in effluent-exposed pike and burbot in both fall and spring. However, there were no lake or season differences in growth indices of length, weight, muscle RNA/DNA ratio, or muscle protein levels in pike. In addition, total lipids and triglycerides in burbot were greater in spring compared to fall, while no seasonal differences were observed in pike, suggesting that burbot continued to feed during winter. Findings do not support the winter stress syndrome hypothesis and suggest possible direct and indirect effects of metal mining effluent on lipid dynamics of juvenile fishes. PMID:17368537

Bennett, Pamela M; Janz, David M

2007-09-01

64

Assessment of larval deformities and selenium accumulation in northern pike (Esox lucius) and white sucker (Catostomus commersoni) exposed to metal mining effluent.  

PubMed

Uranium mining and milling operations in northern Saskatchewan (Canada) release effluents with elevated levels of certain trace metals and metalloids, including selenium. The goal of the present study was to evaluate the presence of selenium-induced deformities in northern pike (Esox lucius) and white sucker (Catostomus commersoni) larvae originating from adults collected downstream of a uranium mine. Eggs were fertilized in the field and incubated in the laboratory following a two-way (crossover) analysis-of-variance experimental design to discriminate effects from maternal transfer versus those from exposure to site water in the developing embryos. Selenium concentrations in northern pike and white sucker eggs (8.02 and 4.89 microg/g dry wt, respectively; mean +/- standard error throughout) from the exposure site were approximately two- to threefold higher than reference (2.35 +/- 0.20 and 1.94 +/- 0.25 microg/g dry wt, respectively). Among all evaluated deformities (skeletal curvatures, craniofacial deformities, fin deformities, and edema), only edema in white sucker fry from the exposure site was slightly elevated ( approximately 3%) compared to reference. The occurrence of edema, however, can be associated with factors other than selenium (e.g., other metals and organic compounds). Both fish species displayed strong linear relationships between the selenium concentrations in eggs and other tissues (muscle, liver, kidney, and bone), suggesting that selenium concentrations in eggs could be predicted from selenium concentrations in adult tissues. The lack of a clear, toxic response in the present study is in agreement with selenium thresholds for early life-stage deformities reported in other studies, with egg selenium concentrations in northern pike and white sucker collected at the exposure site being less than the 10 microg/g (dry wt) threshold associated with the presence of deformities. PMID:18939891

Muscatello, Jorgelina R; Janz, David M

2009-03-01

65

2008. Transactions of the Nebraska Academy of Sciences 31: 43-49 NORTHERN PIKE (ESDX LUCIUS) POPULATION CHARACTERISTICS AND RELATIONS TO  

E-print Network

Knowledge of the population structure of northern pike (Esox lucius), an important recreational and top t t t The northern pike (Esox lucius) is an important recreational fish in North America, including the Nebraska2008. Transactions of the Nebraska Academy of Sciences 31: 43-49 NORTHERN PIKE (ESDX LUCIUS

66

Gill Reaction to Pollutants from the Tamiš River in Three Freshwater Fish Species, Esox lucius L. 1758, Sander lucioperca (L. 1758) and Silurus glanis L. 1758: A Comparative Study.  

PubMed

The study evaluated the effects of waterborne pollutants from the Tamiš River on gill histology and possible differences in gill reaction patterns between three freshwater fish species, pike Esox lucius L. 1758, pike-perch Sander lucioperca (L. 1758) and wels catfish Silurus glanis L. 1758 from the Tamiš River. Gills from analysed fish species showed moderate to intense histopathological alterations. The most frequent progressive alteration was hyperplasia of epithelium, whereas the most frequent regressive alteration was epithelial lifting. Circulatory disturbances were most often manifested in the form of hyperaemia. During comparative analysis, differences in gill indices, reaction and alteration indices, as well as in gill and filament prevalence between analysed species, were observed. Although all analysed fish species did show both progressive and regressive alterations, there was a significant difference in the level of expression of these reaction patterns. Gill index obtained for pike clearly stands out as the lowest. Wels catfish showed the highest progressive reaction index, significantly higher in comparison with the other two species (P < 0.05), while pike-perch showed the highest regressive reaction index, also significantly higher in comparison with the other species (P < 0.001). These results may implicate species-specific gill reactions and thus present a useful tool for better understanding toxic mechanisms of various pollutants. PMID:24809962

Luji?, J; Matavulj, M; Poleksi?, V; Raškovi?, B; Marinovi?, Z; Kosti?, D; Miljanovi?, B

2014-05-01

67

Development of new microsatellite loci and multiplex reactions for muskellunge (Esox masquinongy).  

PubMed

The muskellunge (Esox masquinongy) is a valued fisheries species throughout its native range. Numerous studies have documented performance and phenotypic differences among muskellunge populations, but genetic markers for assessment have been lacking. We characterized 14 microsatellite loci and developed five multiplex polymerase chain reactions. Successful amplification of northern pike (Esox lucius) was observed for seven loci. These microsatellites will be useful for analysing population structure, performance characteristics of propagated strains, and helping to develop and monitor hatchery management guidelines for muskellunge. PMID:21585899

Sloss, Brian L; Franckowiak, Ryan P; Murphy, Edward L

2008-07-01

68

Development of microsatellite markers for muskellunge ( Esox masquinongy ) and cross-species amplification in two other esocids  

Microsoft Academic Search

We report the development of seven polymorphic microsatellite loci in muskellunge ( Esox masquinongy ) using an unenriched subgenomic library. Polymorphic loci exhibited 2-11 alleles with observed heterozygosities ranging from 0.190 to 0.917 ( n = 24). All seven loci amplified by their respective primer pairs resulted in monomorphic products in northern pike ( E. lucius ) whereas three loci

Benjamin J. Reading; Paul S. Wills; Roy C. Heidinger; Edward J. Heist

2003-01-01

69

Development of new microsatellite loci and multiplex reactions for muskellunge (Esox masquinongy)  

USGS Publications Warehouse

The muskellunge (Esox masquinongy) is a valued fisheries species throughout its native range. Numerous studies have documented performance and phenotypic differences among muskellunge populations, but genetic markers for assessment have been lacking. We characterized 14 microsatellite loci and developed five multiplex polymerase chain reactions. Successful amplification of northern pike (Esox lucius) was observed for seven loci. These microsatellites will be useful for analysing population structure, performance characteristics of propagated strains, and helping to develop and monitor hatchery management guidelines for muskellunge. ?? 2008 Blackwell Publishing Ltd.

Sloss, B.L.; Franckowiak, R.P.; Murphy, E.L.

2008-01-01

70

Temporal changes in mercury bioaccumulation by predatory fishes of boreal lakes following the invasion of an exotic forage fish.  

PubMed

We evaluated the prediction that mercury concentrations of predatory fishes in boreal lakes would rise following the invasion of an exotic forage fish species (rainbow smelt, Osmerus mordax) that was believed to feed at a higher trophic position than native forage fishes. We compared temporal trends (postinvasion minus preinvasion values) in fish mercury bioaccumulation between lakes experiencing recent smelt invasions and reference lakes of central Canada. Piscivore mercury concentrations in this region have remained stable or declined during approximately the last 20 years. These trends were not strongly influenced by the smelt invasion, despite the fact that smelt were a major prey item for all piscivore species examined. The effect of smelt invasion on mercury bioaccumulation in the predator species reflected the importance of smelt in their respective diets (lake trout, Salvelinus namaycush > walleye, Stizostedion vitreum > northern pike, Esox lucius). However, these effects were not statistically significant for any piscivore species. The impact of rainbow smelt invasion on mercury bioaccumulation in native piscivores of this region has been much less than previous food-web studies have predicted. PMID:12959531

Johnston, Thomas A; Leggett, William C; Bodaly, Richard A; Swanson, Heidi K

2003-09-01

71

Molecular and phenotypic evidence of a new species of genus Esox (Esocidae, Esociformes, Actinopterygii): the southern pike, Esox flaviae.  

PubMed

We address the taxonomic position of the southern European individuals of pike, performing a series of tests and comparisons from morphology, DNA taxonomy and population genetics parameters, in order to support the hypothesis that two species of pike, and not only one, exist in Europe. A strong relationship emerged between a northern genotype supported by COI, Cytb, AFLP and specific fragments, and a phenotype with round spot skin colour pattern and a large number of scales in the lateral line, clearly separated from a southern genotype with other skin colour pattern and a low number of scales in the lateral line. DNA taxonomy, based on a coalescent approach (GMYC) from phylogenetic reconstructions on COI and Cytb together with AFLP admixture analysis, supported the existence of two independently evolving entities. Such differences are not simply due to geographic distances, as northern European samples are more similar to Canadian and Chinese samples than the southern Europe ones. Thus, given that the differences between the two groups of European pike are significant at the phenotypic, genotypic and geographical levels, we propose the identification of two pike species: the already known northern pike (Esox lucius) and the southern pike (E. flaviae n.sp.). The correct identification of these two lineages as independent species should give rise to a ban on the introduction of northern pikes in southern Europe for recreational fishing, due to potential problems of hybridisation. PMID:22164201

Lucentini, Livia; Puletti, Maria Elena; Ricciolini, Claudia; Gigliarelli, Lilia; Fontaneto, Diego; Lanfaloni, Luisa; Bilò, Fabiana; Natali, Mauro; Panara, Fausto

2011-01-01

72

L'organe pinal du Brochet (Esox lucius, L.). IV. Srotonine endogne et activit monoamine oxydasique ;  

E-print Network

-hydroxytryptophan and/or 5-hydroxytryptamine), the melatonin precursor, was found in different receptor line cells envelope and the plasma membrane. The reaction product, indicative of MAO activity, was comple- tely absent

Paris-Sud XI, Université de

73

Length-weight relationship of northern pike, Esox lucius, from East Harbor, Ohio  

USGS Publications Warehouse

The northern pike is one of Ohio's largest game fish but is well known to comparatively few anglers. Large numbers of the big fish spawn in the Ohio marshes adjacent to Lake Erie. Movements related to spawning reach a peak in late March or early April. Later the spawning population disperses and is seldom represented in catches by experimental gear or by anglers. The short period of availability was used to obtain life history information in March of 1951 through 1953. No comprehensive length-weight data for this species have previously been published from this area. East Harbor is a sandspit pond separated from Lake Erie by a large sand bar. Waters and fish populations of the harbor and lake can mix freely through a permanent connecting channel. The larger part of the 850 surface acres of the harbor is normally less than 8 feet deep. The male northern pike averaged 20.5 inches in length and ranged from 13.5 to 28.5 inches. The conspicuously larger females averaged 26.0 inches and ranged from 15.5 to 37.5 inches.

Brown, Edward H., Jr.; Clark, Clarence F.

1965-01-01

74

Effects of environmental mercury on gonadal function in Lake Champlain northern pike (Esox lucius)  

SciTech Connect

Levels of mercury in the environment have increased steadily over the past two centuries, primarily because of human activity. Common point sources of this heavy metal include industrial waste discharge from chloralkali and paper pulp plants. More diffuse emissions, which become widely distributed by global wind currents, result from the combustion of fossil fuels and incineration of municipal wastes. Stricter laws in the United States have decreased the amount of pollution from point sources. In contrast, mercury from diffuse atmospheric origins has been increasing, causing a rise in rainwater concentrations and aquatic environments frequently distant from the source of pollution. Once in aquatic systems, mercury is readily converted to the more toxic methylated form and is the only heavy metal that indisputably biomagnifies through the food web. Acid rain compounds the environmental impact of anthropogenic mercury because aquatic organisms concentrate more mercury when living in waters with lower alkalinity. The persistence of this heavy metal in teleosts is illustrated by the finding that mercury, unlike cadmium, arsenic, and lead, did not decrease in North American freshwater fish between 1976 and 1984.

Friedmann, A.S.; Leiter, J.C. [Dartmouth Medical School, Lebanon, NH (United States)] [Dartmouth Medical School, Lebanon, NH (United States); Watzin, M.C. [Univ. of Vermont, Burlington, VT (United States)] [and others] [Univ. of Vermont, Burlington, VT (United States); and others

1996-03-01

75

Effects of Environmental Mercury on Gonadal Function in Lake Champlain Northern Pike ( Esox lucius )  

Microsoft Academic Search

Levels of mercury in the environment have increased steadily over the past two centuries, primarily because of human activity. Common point sources of this heavy metal include industrial waste discharge from chloralkali and paper pulp plants. More diffuse emissions, which become widely distributed by global wind currents, result from the combustion of fossil fuels and incineration of municipal wastes. Stricter

A. S. Friedmann; M. C. Watzin; J. C. Leiter; T. Brinck-Johnsen

1996-01-01

76

Food of Young Pike, Esox Lucius L., and Associated Fishes in Peterson's Ditches, Houghton Lake, Michigan  

Microsoft Academic Search

Stomach contents of 551 young pike (11–152 millimeters in length), 345 small yellow perch, and 431 other fish representing 18 species were examined. All specimens were collected from an area widely used by spawning pike from Houghton Lake, Michigan. Organisms utilized for food by young pike included Entomostraca, insects (chiefly Chironomidae), tadpoles, minnows, darters, and other pike. As pike increased

Burton P. Hunt; William F. Carbine

1951-01-01

77

Fine-scale oscillatory banding in otoliths from arctic charr (Salveninus alpinus) and pike (Esox lucius)  

SciTech Connect

Transmission electron microscopy of otoliths from the inner ear of arctic charr and pike has revealed the presence of fine banding on the scale of several nanometers. The thickness of the bands was observed to vary in different portions of the sample, and some areas were not banded. EDS analysis could not detect chemical differences within the bands, but electron diffraction showed that the crystallographic orientation of the bands is related by a lattice mismatch. Previously, banding on the scale of 50 to 100 microns was observed by SEM in otoliths from arctic charr and was attributed to seasonal variations in growth. The fine-scale banding observed in this study, however, is unlikely to represent a daily variation. Electron diffraction from the pike samples shows that the material is composed of CaCO{sub 3} having the both the vaterite and aragonite structure, and hydrous CaCO{sub 3} was also observed. The large-scale banding previously identified by SEM was not observed in the TEM despite attempts to intersect the boundaries of the micron-sized layers. The interaction of the electron beam with the sample material was investigated by conducting several electron-irradiation experiments. The electron beam was observed to interact strongly with the sample and caused the precipitation of cubic CaO from the calcium carbonate matrix. Bright-field imaging showed the development of fine grained ({approximately} 5 nm) randomly oriented crystallites which accumulated with increasing electron dose. These initial results suggest that the precipitation of CaO is not driven by electron-beam beating. Previously, a similar phase-change phenomenon has been observed in hydroxyapatite from dental enamel. Other Ca-bearing biominerals may therefore also be expected to be sensitive to electron irradiation.

Meldrum, A. [Oak Ridge National Lab., TN (United States); Halden, N.M. [Univ. of Manitoba, Winnipeg (Canada). Dept. of Geological Sciences

1997-12-31

78

Effects of predator species, vegetation and prey assemblage on prey preferences of predators with  

E-print Network

); largemouth bass, Micropterus salmoides (Lacepe` de); smallmouth bass, M. dolomieu Lacepe` de; walleye, Sander vitreus (Mitchill); and northern pike, Esox lucius L.) foraging on juvenile common carp and two

79

A toxicological examination of whitefish ( Coregonus clupeaformis ) and northern pike ( Esox lucius ) exposed to uranium mine tailings  

Microsoft Academic Search

Operation of the Gunnar uranium mine, in northern Saskatchewan, Canada, from 1955 to 1964, resulted in the deposition of radioactive tailings in Langley Bay, a small bay connected to Lake Athabasca. Previous publications have described the contamination of the sediments, water, macrophytes and fish of this area. The present study compares the parasite infestations, blood hematocrit, histopathology and condition factor

D. T. Waite; S. R. Joshi; H. Sommerstad; G. Wobeser; A. A. Gajadhart

1990-01-01

80

A toxicological examination of whitefish (Coregonus clupeaformis) and northern pike (Esox lucius) exposed to uranium mine tailings.  

PubMed

Operation of the Gunnar uranium mine, in nothern Saskatchewan, Canada, from 1955 to 1964, resulted in the deposition of radioactive tailings in Langley Bay, a small bay connected to Lake Athabasca. Previous publications have described the contamination of the sediments, water, macrophytes and fish of this area. The present study compares the parasite infestations, blood hematocrit, histopathology and condition factor (K) of the Langley Bay whitefish and northern pike populations with these factors measured for control populations from Lake Athabasca. No significant differences could be found, in any of the physiological parameters measured, between the contaminated and control populations. PMID:2386411

Waite, D T; Joshi, S R; Sommerstad, H; Wobeser, G; Gajadhar, A A

1990-01-01

81

Historical analysis of genetic variation reveals low effective population size in a northern pike (Esox lucius) population.  

PubMed

Effective population size (Ne) of a natural fish population was estimated from temporal changes in allele frequencies at seven microsatellite loci. Use of a historical collection of fish scales made it possible to increase the precision of estimates by increasing the time interval between samples and to use an equation developed for discrete generations without correcting for demographic parameters. Estimates of Ne for the time intervals 1961-1977 and 1977-1993 were 35 and 72, respectively. For the entire interval, 1961-1993, the estimate of Ne was 48 when based on a weighted mean derived from the above two estimates or 125 when calculated from 1961 and 1993 samples only. Corresponding ratios of effective size to adult census size ranged from 0.03 to 0.14. An Ne of 48 over a 32-year period would imply that this population lost as much as 8% of its heterozygosity in that time. Results suggest the potential for using genetic methods based on microsatellite loci data to compare historical trends in Ne with population dynamic parameters. Such comparisons will help to evaluate the relationship between genetic diversity and long-term persistence of natural populations. PMID:9383067

Miller, L M; Kapuscinski, A R

1997-11-01

82

Historical Analysis of Genetic Variation Reveals Low Effective Population Size in a Northern Pike (Esox Lucius) Population  

PubMed Central

Effective population size (N(e)) of a natural fish population was estimated from temporal changes in allele frequencies at seven microsatellite loci. Use of a historical collection of fish scales made it possible to increase the precision of estimates by increasing the time interval between samples and to use an equation developed for discrete generations without correcting for demographic parameters. Estimates of N(e) for the time intervals 1961-1977 and 1977-1993 were 35 and 72, respectively. For the entire interval, 1961-1993, the estimate of N(e) was 48 when based on a weighted mean derived from the above two estimates or 125 when calculated from 1961 and 1993 samples only. Corresponding ratios of effective size to adult census size ranged from 0.03 to 0.14. An N(e) of 48 over a 32-year period would imply that this population lost as much as 8% of its heterozygosity in that time. Results suggest the potential for using genetic methods based on microsatellite loci data to compare historical trends in N(e) with population dynamic parameters. Such comparisons will help to evaluate the relationship between genetic diversity and long-term persistence of natural populations. PMID:9383067

Miller, L. M.; Kapuscinski, A. R.

1997-01-01

83

Pineal-retinal relationships: rhythmic biosynthesis and immunocytochemical localization of melatonin in the retina of the pike ( Esox lucius )  

Microsoft Academic Search

The levels of melatonin and the activities of two enzymes of the melatonin biosynthetic pathway, serotonin N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT), were measured throughout the light-dark cycle in the retina of a teleost fish, the pike. HIOMT activity did not display significant variations, whereas NAT activity and melatonin content showed a daily rhythm, high levels occurring during the night. The

Jacky Falcón; Jean-Pierre Collin

1991-01-01

84

Ultrastructure of atrial and ventricular myocardium in the pike Esox lucius L. and mackerel Scomber scombrus L. (Pisces)  

Microsoft Academic Search

Atrial and ventricular muscle in the pike and mackerel hearts consists of narrow, branching cells. The atrial cells in the two species are similar whereas the ventricular cells differ. The sarcolemma is attached to the Z and M lines of the sarcomere. Intercalated discs are common, and the transverse parts display desmosomes and intermediate junctions. Nexuses are uncommon and only

Bjørn Midttun

1980-01-01

85

The influence of angling-induced exercise on the carbohydrate metabolism of northern pike ( Esox lucius L.)  

Microsoft Academic Search

Summary  Capture by angling was used to induce burst exercise in northern pike. By 3 h after exercise blood lactate had risen to levels\\u000a of 15.2 mmol l?1 (Fig. 2), which greatly exceeded the maximum post-exercise levels (4.0 mmol l?1) previously reported for muskellunge, a close relative of pike. White muscle lactate level was high, 41.8 mmol kg?1, immediately after capture

K. Schwalme; W. C. Mackay

1985-01-01

86

Northern pike ( Esox lucius L.) and aquatic vegetation, tools in the management of fisheries and water quality in shallow waters  

Microsoft Academic Search

Species and size composition of fish communities in shallow stagnant waters appear to be associated with the type, abundance and pattern of the vegetation. Man-induced impacts as eutrophication, and suppression of vegetation for reasons of water quantity management or angling pleasure may induce irreversible changes in the aquatic ecosystem. Water quality management should aim at restoring former pike habitat. Submerged

M. P. Grimm

1989-01-01

87

Pike (Esox lucius L.) stocking as a biomanipulation tool 2. Effects on lower trophic levels in Lake Lyng, Denmark  

Microsoft Academic Search

In order to study how pike stocking affects trophic structurepikefingerlings (0–3600 ha-1) were stocked during six yearsineutrophic Lake Lyng (lake area 10 ha), Denmark. Subsequently,marked changes were recorded in the abundance ofzooplanktivorousfish, catch per unit effort of roach, which was the dominantfishspecies, thus varied from 17 to 272. Simultaneously, markedchangeswere recorded in the abundance and relative composition ofzooplankton. Daphnia abundance

Martin Søndergaard; Erik Jeppesen; Søren Berg

1997-01-01

88

Four decades of opposing natural and human-induced artificial selection acting on Windermere pike (Esox lucius)  

Microsoft Academic Search

The ability of natural selection to drive local adaptation has been appreciated ever since Darwin. Whether human impacts can impede the adaptive process has received less attention. We tested this hypothesis by quantifying natural selection and harvest selection acting on a freshwater fish (pike) over four decades. Across the time series, directional natural selection tended to favour large individuals whereas

Stephanie M. Carlson; Eric Edeline; L. Asbjørn Vøllestad; Thrond. O. Haugen; Ian J. Winfield; Janice M. Fletcher; J. Ben James; Nils Chr. Stenseth

2007-01-01

89

PILOT EVALUATION OF ENHANCED E-SOX PROCESS  

EPA Science Inventory

The paper discusses pilot-plant tests with a 28 cu m/min (1000 cfm)electrostatic precipitator (ESP) to evaluate techniques that havea potential for enhancing the S02 removal of the E-SOx process forretrofit application. he techniques investigated includedmass-transfer additives, ...

90

Transactions of the American Fisheries Society 129:186193, 2000 Copyright by the American Fisheries Society 2000  

E-print Network

fit between predicted and observed food consumption for northern pike Esox lucius. Similarly, poor, 1999 kellunge Esox masquinongy and tiger muskellunge Esox masquinongy E. lucius (Wahl and Stein 1991

91

Forage Budgeting  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pasture management in tropical agro-ecosystems is challenging because of unique soil, climate, and animal interactions. Budgeting forage as part of the grazing system can be difficult because of the strong seasonality of forage production and rapidly changing forage quality. Planning, measuring, and...

92

The Genome and Linkage Map of the Northern Pike (Esox lucius): Conserved Synteny Revealed between the Salmonid Sister Group and the Neoteleostei  

PubMed Central

The northern pike is the most frequently studied member of the Esociformes, the closest order to the diverse and economically important Salmoniformes. The ancestor of all salmonids purportedly experienced a whole-genome duplication (WGD) event, making salmonid species ideal for studying the early impacts of genome duplication while complicating their use in wider analyses of teleost evolution. Studies suggest that the Esociformes diverged from the salmonid lineage prior to the WGD, supporting the use of northern pike as a pre-duplication outgroup. Here we present the first genome assembly, reference transcriptome and linkage map for northern pike, and evaluate the suitability of this species to provide a representative pre-duplication genome for future studies of salmonid and teleost evolution. The northern pike genome sequence is composed of 94,267 contigs (N50?=?16,909 bp) contained in 5,688 scaffolds (N50?=?700,535 bp); the total scaffolded genome size is 878 million bases. Multiple lines of evidence suggest that over 96% of the protein-coding genome is present in the genome assembly. The reference transcriptome was constructed from 13 tissues and contains 38,696 transcripts, which are accompanied by normalized expression data in all tissues. Gene-prediction analysis produced a total of 19,601 northern pike-specific gene models. The first-generation linkage map identifies 25 linkage groups, in agreement with northern pike's diploid karyotype of 2N?=?50, and facilitates the placement of 46% of assembled bases onto linkage groups. Analyses reveal a high degree of conserved synteny between northern pike and other model teleost genomes. While conservation of gene order is limited to smaller syntenic blocks, the wider conservation of genome organization implies the northern pike exhibits a suitable approximation of a non-duplicated Protacanthopterygiian genome. This dataset will facilitate future studies of esocid biology and empower ongoing examinations of the Atlantic salmon and rainbow trout genomes by facilitating their comparison with other major teleost groups. PMID:25069045

Rondeau, Eric B.; Minkley, David R.; Leong, Jong S.; Messmer, Amber M.; Jantzen, Johanna R.; von Schalburg, Kristian R.; Lemon, Craig; Bird, Nathan H.; Koop, Ben F.

2014-01-01

93

Spatial relations of mercury contents in Pike (Esox lucius) and sediments concentration of the Anzali wetland, along the southern shores of the Caspian Sea, Iran.  

PubMed

In recent decades, the Anzali wetland has been threatened and destroyed by environmental pollution from several sources. The purpose of this study was to determine the possible relationships between mercury concentrations in Pike and their respective sediments within the assumed multiple activity center scales of Pike (100, 250 and 500 m in radius). To gain a better understanding spatial distribution pattern of Hg in sediments and to pursue the main purpose of this study, kriging (geostatistic spatial interpolation method) was applied. Poor relationships were found between mercury concentrations of Pike and sediments within the assumed multiple activity center scales of Pike. The mercury sediment influence diminished with the increasing radii of assumed activity centers. The results of the present study indicate that fish and sediment mercury concentrations in western parts of the Anzali wetland were low in comparison with the concentrations reported in the literature from other regions. PMID:24933165

Zamani-Ahmadmahmoodi, Rasool; Bakhtiari, Alireza Riyahi; Rodríguez Martín, José Antonio

2014-07-15

94

Stocking impact and temporal stability of genetic composition in a brackish northern pike population (Esox lucius L.), assessed using microsatellite DNA analysis of historical and contemporary samples.  

PubMed

During the last decade, brackish northern pike populations in Denmark have been subject to stocking programmes, using nonindigenous pike from freshwater lakes, in order to compensate for drastic population declines. The present study was designed to investigate the genetic impact of stocking freshwater pike into a brackish pike population in Stege Nor, Denmark. We analysed polymorphism at eight microsatellite loci in samples representing the indigenous Stege Nor population prior to stocking (ie from 1956 to 1957), along with a sample of the contemporary Stege Nor population and samples from the three populations used for stocking. Despite large numbers of stocked fry, the results from both individual and population level admixture analyses demonstrated extremely poor performance and <1% introgression of stocked freshwater pike into the brackish pike population. Furthermore, pairwise F(ST) estimates between samples demonstrated close genetic relationship among temporal samples from Stege Nor, indicating temporal stability over the last 45 years. We also estimated the effective population size (N(e)) of pike in Stege Nor and applied a test for recent population bottlenecks. The harmonic mean of N(e) was relatively high (>250), but there were indications of bottlenecks in all samples and populations. We ascribe this finding to historical rather than recent bottlenecks, possibly dating back to founder events associated with postglacial recolonisation. PMID:15999144

Larsen, P F; Hansen, M M; Nielsen, E E; Jensen, L F; Loeschcke, V

2005-08-01

95

The effects of season on fatty acid composition and ?3/?6 ratios of northern pike ( Esox lucius L., 1758) muscle lipids  

NASA Astrophysics Data System (ADS)

In the present study, the effects of season on fatty acid composition, total lipids, and ?3/?6 ratios of northern pike muscle lipids in Kizilirmak River (Kirikkale, Turkey) were investigated. A total of 35 different fatty acids were determined in gas chromatography. Among these, palmitic, oleic, and palmitoleic acids had the highest proportion. The main polyunsaturated fatty acids (PUFAs) were found to be docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid. There were more PUFAs than monounsaturated fatty acids (MUFA) in all seasons. Similarly, the percentages of ?3 fatty acids were higher than those of total ?6 fatty acids in the fatty acid composition. ?3/?6 ratios were calculated as 1.53, 1.32, 1.97, and 1.71 in spring, summer, autumn and winter, respectively. Overall, we found that the fatty acid composition and ?3/?6 fatty acid ratio in the muscle of northern pike were significantly influenced by season.

Mert, Ramazan; Bulut, Sait; Konuk, Muhsin

2015-01-01

96

A survey of the spawning of perch (Perca fluviatilis), pike (Esox lucius), and roach (Rutilus rutilus), using artificial spawning substrates in lakes  

Microsoft Academic Search

The development of spawning in perch, pike and roach in Lake Geneva has been studied by means of artificial spawning substrates, laid at different depths, from 1984 to 1993. In Lake Geneva, perch spawned in May. A rise of surface water temperature up to 14 °C stimulated spawning activity while bad weather (surface temperature at 10 °C) induced a spread

C. Gillet; J. P. Dubois

1995-01-01

97

The contribution of ventricular apicobasal and transmural repolarization patterns to the development of the T wave body surface potentials in frogs (Rana temporaria) and pike (Esox lucius).  

PubMed

The study aimed at the simultaneous determination of the transmural and apicobasal differences in the repolarization timing and the comparison of the contributions of these two repolarization gradients to the development of the body surface T wave potentials in animals with the single heart ventricle (fishes and amphibians). Unipolar potentials were measured on the body surface, epicardium and in the intramural (subepicardial, Epi; midmyocardial; and subendocardial, Endo) ventricular layers of 9 pike and 8 frogs. Activation times, repolarization times and activation-recovery intervals were determined. A transmural gradient in repolarization durations in frogs (Endo>Epi, P<0.024) corresponds to the gradient in repolarization times. No significant transmural difference in repolarization duration is observed in pike that produces a repolarization sequence from Endo to Epi (Endo

Vaykshnorayte, Marina A; Azarov, Jan E; Tsvetkova, Alena S; Vityazev, Vladimir A; Ovechkin, Alexey O; Shmakov, Dmitry N

2011-05-01

98

Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on early life stages of the pike (Esox lucius L.)  

Microsoft Academic Search

Freshly fertilized pike eggs were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) at concentrations of 0.1, 1.0 and 10 ppt (ng\\/liter) for 96 hours. At all concentrations examined egg development was retarded by 23%, and the growth of fry was also significantly retarded for a long period after exposure. A dose-related mortality was observed. Highest mortality rates occurred during resorption of the yolk

T. Helder

1980-01-01

99

Production, consumption and prey availability of northern pike ( Esox lucius ), pikeperch ( Stizostedion lucioperca ) and European catfish ( Silurus glanis ): a bioenergetics approach  

Microsoft Academic Search

Bioenergetics models were applied for the assessment of food consumption of northern pike, pikeperch and European catfish\\u000a in drainable ponds of 0.4 ha. The ponds were stocked with known numbers of the 0+ predators. The prey fish consisted of naturally recruited 0+ cyprinids (rudd, roach and bream). The study shows that the impact of the three 0+ piscivores on the

Alexander J. P. Raat

1990-01-01

100

Early Life History of the Northern Pike, Esox lucius L., with Special Reference to the Factors Influencing the Numerical Strength of Year Classes  

Microsoft Academic Search

The early life history of northern pike was studied to determine the relationship of adult pike abundance to the strength of resulting year classes and the existence and chronology of critical survival periods, along with the nature and origin of the mortality mechanisms involved. Adult abundance and the strength of the resulting year classes were not directly related. Two critical

Donald R. Franklin; Lloyd L. Smith Jr

1963-01-01

101

The genome and linkage map of the northern pike (Esox lucius): conserved synteny revealed between the salmonid sister group and the Neoteleostei.  

PubMed

The northern pike is the most frequently studied member of the Esociformes, the closest order to the diverse and economically important Salmoniformes. The ancestor of all salmonids purportedly experienced a whole-genome duplication (WGD) event, making salmonid species ideal for studying the early impacts of genome duplication while complicating their use in wider analyses of teleost evolution. Studies suggest that the Esociformes diverged from the salmonid lineage prior to the WGD, supporting the use of northern pike as a pre-duplication outgroup. Here we present the first genome assembly, reference transcriptome and linkage map for northern pike, and evaluate the suitability of this species to provide a representative pre-duplication genome for future studies of salmonid and teleost evolution. The northern pike genome sequence is composed of 94,267 contigs (N50 = 16,909 bp) contained in 5,688 scaffolds (N50 = 700,535 bp); the total scaffolded genome size is 878 million bases. Multiple lines of evidence suggest that over 96% of the protein-coding genome is present in the genome assembly. The reference transcriptome was constructed from 13 tissues and contains 38,696 transcripts, which are accompanied by normalized expression data in all tissues. Gene-prediction analysis produced a total of 19,601 northern pike-specific gene models. The first-generation linkage map identifies 25 linkage groups, in agreement with northern pike's diploid karyotype of 2N = 50, and facilitates the placement of 46% of assembled bases onto linkage groups. Analyses reveal a high degree of conserved synteny between northern pike and other model teleost genomes. While conservation of gene order is limited to smaller syntenic blocks, the wider conservation of genome organization implies the northern pike exhibits a suitable approximation of a non-duplicated Protacanthopterygiian genome. This dataset will facilitate future studies of esocid biology and empower ongoing examinations of the Atlantic salmon and rainbow trout genomes by facilitating their comparison with other major teleost groups. PMID:25069045

Rondeau, Eric B; Minkley, David R; Leong, Jong S; Messmer, Amber M; Jantzen, Johanna R; von Schalburg, Kristian R; Lemon, Craig; Bird, Nathan H; Koop, Ben F

2014-01-01

102

Biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) studied in pike ( Esox lucius), perch ( Perca fluviatilis) and roach ( Rutilus rutilus) from the Baltic Sea  

Microsoft Academic Search

Pike, perch and roach from rural waters of the Baltic Sea were investigated for possible biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). For this we used data on ?15N, weight and sex of the fish. We were able to separate body size effects from trophic position effects on biomagnification. Both these parameters lead to biomagnification of PCBs

Sven Burreau; Yngve Zebühr; Dag Broman; Rasha Ishaq

2004-01-01

103

Reproductive status and lipid content as factors in PCB, DDT and HCH contamination of a population of pike (Esox lucius L. )  

Microsoft Academic Search

Levels of persistent pollutants, including PCBs, [Sigma]DDT, and [gamma]-hexachlorocyclohexane, were examined in a pike population inhabiting a eutrophic lake in southern Scandinavia. For females, levels of persistent pollutants decreased linearly with age, weight, or length. This decline was ascribed to the seasonal elimination of the lipophilic pollutants in roe, which contained up to 10 times higher fat levels compared to

Per Larsson; Lennart Okla; Lars Collvin

1993-01-01

104

Reproductive status and lipid content as factors in PCB, DDT and HCH contamination of a population of pike (Esox lucius L. )  

SciTech Connect

Levels of persistent pollutants, including PCBs, [Sigma]DDT, and [gamma]-hexachlorocyclohexane, were examined in a pike population inhabiting a eutrophic lake in southern Scandinavia. For females, levels of persistent pollutants decreased linearly with age, weight, or length. This decline was ascribed to the seasonal elimination of the lipophilic pollutants in roe, which contained up to 10 times higher fat levels compared to muscle and over 10 times the amounts of pollutants. Male pike contained higher levels of pollutants than females, probably due to the lower elimination via gonadal products, as germinal tissue constitutes only 2% of the male total body weight and has a lower fat content than ovaries. Female germinal tissue can account for as much as 15% of the body weight. No major fat deposits other than those in germinal tissue were found in pike, which also had a low muscle fat content, suggesting that the importance of roe elimination in removing pollutants may be greater in pike than in salmonids. Uptake of persistent pollutants can vary greatly within a species, owing to differences in sex, age, and so forth, as well as between species, owing to differences in fat deposition strategies.

Larsson, P.; Okla, L.; Collvin, L. (Dept. of Ecology, Lund (Sweden))

1993-05-01

105

The effects of season on fatty acid composition and ?3/?6 ratios of northern pike (Esox lucius L., 1758) muscle lipids  

NASA Astrophysics Data System (ADS)

In the present study, the effects of season on fatty acid composition, total lipids, and ?3/?6 ratios of northern pike muscle lipids in K?z?l?rmak River (K?r?kkale, Turkey) were investigated. A total of 35 different fatty acids were determined in gas chromatography. Among these, palmitic, oleic, and palmitoleic acids had the highest proportion. The main polyunsaturated fatty acids (PUFAs) were found to be docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid. There were more PUFAs than monounsaturated fatty acids (MUFA) in all seasons. Similarly, the percentages of ?3 fatty acids were higher than those of total ?6 fatty acids in the fatty acid composition. ?3/?6 ratios were calculated as 1.53, 1.32, 1.97, and 1.71 in spring, summer, autumn and winter, respectively. Overall, we found that the fatty acid composition and ?3/?6 fatty acid ratio in the muscle of northern pike were significantly influenced by season.

Mert, Ramazan; Bulut, Sait; Konuk, Muhsin

2014-10-01

106

ORIGINAL PAPER Assessing evolutionary consequences of size-selective  

E-print Network

on multiple life-history traits, with an application to northern pike (Esox lucius) Shuichi Matsumura · Robert- selective exploitation of northern pike (Esox lucius L.) with recreational-fishing gear. An age

Dieckmann, Ulf

107

North American Journal of Fisheries Management 15 :838-844, 1995 Copyright by the American Fisheries Society 1995  

E-print Network

pike Esox lucius in 416 gill-net sets on 17 monthly oc- casions from July 1991 to June 1993 to examine of northern pike Esox lucius (Fisheries Techniques Standardization Committee 1992) . Seasonal variations

108

ORIGINAL ARTICLE Quantifying selection differentials caused by recreational  

E-print Network

of modeling framework and application to reproductive investment in pike (Esox lucius) Robert Arlinghaus,1-selective exploitation in a highly demanded freshwater recreational fish species, northern pike (Esox lucius L.). We find

Dieckmann, Ulf

109

Journal of Aquatic Ecosystem Stress and Recovery 9: 137147, 2002. 2002 Kluwer Academic Publishers. Printed in the Netherlands.  

E-print Network

salmoides) and northern pike (Esox lucius). We compared simulations using field data to hypothetical taken. For instance, northern pike (Esox lucius) are more strict piscivores compared to largemouth bass

110

Fisheries Research 97 (2009) 223233 Contents lists available at ScienceDirect  

E-print Network

-and-release angling on northern pike (Esox lucius L.) Robert Arlinghausa,b, , Thomas Klefotha , Steven J. Cookec stressors using a combined laboratory and field study in northern pike (Esox lucius L.). A labora- tory

Suski, Cory David

111

Walleye and Northern Pike: Boost or Bane to Northwest Fisheries?  

E-print Network

(Esox lucius) have created popular recreational fisheries in many Northwestern waters. Rising demand popularity of nonnative walleye (Stizostedion vit- reum) and northern pike (Esox lucius) as sport fishes has

McMahon, Thomas E.

112

Trait changes in a harvested population are driven by a dynamic tug-of-war between  

E-print Network

-based data on Windermere pike (Esox lucius), we show that trait changes tracked the adaptive peak, which populations. We performed this task in pike (Esox lucius) from Windermere, U.K. This system is particu- larly

Carlson, Stephanie

113

Diet and Growth of Northern Pike in the Absence of Prey Fishes: Initial Consequences for Persisting in Disturbance-Prone Lakes  

E-print Network

of Alberta, Edmonton, Alberta T6G 2E9, Canada Abstract.--The northern pike Esox lucius is a renowned to stunting. The northern pike Esox lucius is considered to be piscivorous throughout most of its circumpolar

Venturelli, Paul

114

This article was originally published in a journal published by Elsevier, and the attached copy is provided by Elsevier for the  

E-print Network

-tagged hatchery-reared young-of-the-year northern pike Esox lucius (mean fork length FL 51.0 mm ± 5.3 S: Passive integrated transponder; Portable detector; Esox lucius; Survival; Stocking program 1. Introduction Northern pike (Esox lucius) is a predatory keystone species that tolerates a broad range of environmental

Cucherousset, Julien

115

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research  

E-print Network

pike (Esox lucius L.) S.M. Hadi Alavi a,*, Marek Rodina a , Ana T.M. Viveiros b , Jacky Cosson c; received in revised form 23 January 2009; accepted 25 January 2009 Abstract Northern pike (Esox lucius L reserved. Keywords: Esox lucius; Sperm; SEM; Flagella; Osmolality 1. Introduction

Villefranche sur mer

116

Effects of E-SOx technology on ESP performance. Final report, Aug-Nov 90  

SciTech Connect

The report gives results of an evaluation of the E-SOx process at Ohio Edison's Burger Station. Adequate sulfur dioxide (SO2) removal and acceptable particulate emission levels from the electrostatic precipitator (ESP) were the prime objectives of the investigation. The report describes limited ESP performance testing under both baseline and E-SOx conditions. The ESP data collected under E-SOx conditions, which give the required 50% SO2 removal, show evidence of ESP performance dominated by factors not represented in existing versions of ESP performance models. These analyses and other considerations indicate that the factors which dominate under the conditions tested are a combination of instantaneous reentrainment of low resistivity ash/sorbent particles and deagglomeration of slurry residues within the ESP. These observations may be important to other sorbent injection processes as well as to E-SOx. Improvement of the gas velocity and temperature distributions at the ESP inlet improved the ESP performance, but performance was still dominated by the reentrainment process and was therefore lower than mathematical model predictions.

Marchant, G.H.; Gooch, J.P.; Faulkner, M.G.

1992-10-01

117

EVALUATION OF THE E-SOX PROCESS ON THE EPA PILOT ELECTROSTATIC PRECIPITATOR  

EPA Science Inventory

The report gives results of a small pilot-scale evaluation of the E-SOx process, undertaken to obtain information needed to conduct a planned 5 MWe field pilot demonstration. he process uses an electrostatic precipitator (ESP) for combined sulfur dioxide (SO2) removal and particu...

118

Information Foraging  

E-print Network

Information foraging theory is an approach to understanding how strategies and technologies for information seeking, gathering, and consumption are adapted to the flux of information in the environment. The theory assumes that people, when possible, will modify their strategies or the structure of the environment to maximize their rate of gaining valuable information. The theory is developed by (a) adaptation (rational) analysis of information foraging problems and (b) a detailed process model (adaptive control of thought in information foraging [ACT-IF]). The adaptation analysis develops (a) information patch models, which deal with time allocation and information filtering and enrichment activities in environments in which information is encountered in clusters; (b) information scent models, which address the identification of information value from proximal cues; and (c) information diet models, which address decisions about the selection and pursuit of information items. ACT-IF is instantiated as a production system model of people interacting with complex information technology. Humans actively seek, gather, share, and consume information to a degree unapproached by other organisms. Ours might properly be characterized as a species of informavores (Dennett, 1991). Our adaptive success depends to a large extent on a vast and complex

Peter Pirolli; Stuart Card

1999-01-01

119

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

PubMed

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

Tan, W B; Lim, L H S

2009-09-01

120

Uptake and depletion of plasma 17?-methyltestosterone during induction of masculinization in muskellunge, Esox masquinongy  

Microsoft Academic Search

Oral administration of 17?-methyltestosterone (MT) was used to induce masculinization of sexually undifferentiated muskellunge, Esox masquinongy. Three groups of muskellunge (mean weight, 2.5 ± 0.6 g) were submitted to MT treatment (15 mg of MT\\/kg) for 60 days. An additional one group was used as a control (hormone-free diet). Food was distributed over a 10-h period by using automatic belt

Jacques Rinchard; Konrad Dabrowski; Joseph Ottobre

1999-01-01

121

Interactions of multiple predators with different foraging modes in an aquatic food web.  

PubMed

Top predators can have different foraging modes that may alter their interactions and effects on food webs. Interactions between predators may be non-additive resulting from facilitation or interference, whereas their combined effects on a shared prey may result in emergent effects that are risk enhanced or risk reduced. To test the importance of multiple predators with different foraging modes, we examined the interaction between a cruising predator (largemouth bass, Micropterus salmoides) and an ambush predator (muskellunge, Esox masquinongy) foraging on a shared prey (bluegill sunfish, Lepomis macrochirus) with strong anti-predator defense behaviors. Additive and substitution designs were used to compare individual to combined predator treatments in experimental ponds. The multiple predator interaction facilitated growth of the cruising predator in the combined predator treatments, whereas predator species had substitutable effects on the growth of the ambush predator. The combined predator treatments created an emergent effect on the prey; however, the direction was dependent on the experimental design. The additive design found a risk-reducing effect, whereas the substitution design found a risk-enhancing effect for prey fish. Indirect effects from the predators weakly extended to lower trophic levels (i.e., zooplankton community). Our results highlight the need to consider differences in foraging mode of top predators, interactions between predators, and emergent effects on prey to understand food webs. PMID:19777265

Carey, Michael P; Wahl, David H

2010-02-01

122

Communiqu de presse 10 septembre 2014 Un brochet en France peut en cacher deux autres  

E-print Network

Esox lucius est un poisson emblématique en France, où il fait l'objet d'un fort intérêt pour la pêche qu'il n'existait qu'une seule espèce de brochet (Esox lucius) en Europe. Or en 2011, une nouvelle aquitanicus (a), et le brochet commun Esox lucius (b). 1 Onema : Office national de l'eau et des milieux

123

This is an author-deposited version published in: http://oatao.univ-toulouse.fr/ Eprints ID: 6158  

E-print Network

roach (Rutilus rutilus L.), perch (Perca fluviatilis L.), and pike (Esox lucius L.). The two methods vegetation. It is likely microhabitat; scuba diving; lake; Rutilus rutilus; Perca fluviatilis; Esox

Paris-Sud XI, Université de

124

North American Journal of Fisheries Management 9:488-492, 1989 Copyright by the American Fisheries Society 1989  

E-print Network

) is an index used to quantify length-frequency data. The PSD of populations ofnorthern pike Esox lucius- son and Weithman (1978) suggested that walleyes Stizostedion vitreum and northern pike Esox lu- cius

125

Trophic ecology of largemouth bass and northern pike in allopatric and sympatric assemblages in  

E-print Network

(Mieropferus salmoides) and northern pike (Esox lucius) are top predators in the food chain in most aquatic overlap. Resume: L'Achigan it grande bouche (Mieropferus salmoides) et Ie Brochet du Nord (Esox lucills

126

FORAGES - CHAPTER 19  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water use by forage crops is an important component of water management in the western United States where it constitutes a significant proportion of the irrigated land. Forage crops account for 57 percent of the total irrigated area in the eight western states of Colorado, Idaho, Montana, Nevada, ...

127

Understanding Forage Quality Analysis  

E-print Network

Understanding Forage Quality Analysis Sandra R. Stokes and Eric P. Prostko* L-5198 3-98 M any dairy producers in Texas do not have the land to grow their own forages. Consequent- ly, they rely on both local and out-of-state farmers for supplies...

Stokes, Sandra R.; Prostko, Eric P.

1998-03-23

128

Forages for Beef Cattle  

E-print Network

in energy content of various forages relative to the requirements of various classes of cattle. Forages for Beef Cattle David Bade and Donald J. Dorsett* Warm-season perennial grasses respond well to fertil- ization and, with heavy fertilization, can produce...

Bade, David H.; Dorsett, Donald J.

2002-09-05

129

Time trends of chlordane, DDT, and PCB concentrations in pike ( Esox lucius ) and Baltic herring ( Clupea harengus ) in the Turku archipelago, northern Baltic sea for the period 1971–1982  

Microsoft Academic Search

The concentrations of PCB- and DDT-compounds in Baltic wildlife have been extensively studied during the last decade. Since the use of DDT was banned in the early 70's in many countries, including those in Baltic area, the level of DDT-compounds has decreased in the Baltic environment by PAASIVIRTA and LINKO (198o)o The use of PCBcompounds is now banned in Sweden

Raija Moilanen; Heikki Pyysalo; Kim Wickström; Reino Linko

1982-01-01

130

Redefining Honeybee Foraging Cognition  

E-print Network

The research in this manuscript was designed to investigate all of the facets of current honeybee foraging knowledge. In order to do so, we constructed new methodologies to provide more accurate data for a finer level of analysis. Specifically, we...

Najera, Daniel Arnulfo

2009-04-28

131

Forage Quality Photo Guide  

E-print Network

The relationship between forage quality and the physical appearance of feces of grazing cattle is explained. Four photographs provide a quick and easy visual reference for evaluating the diet quality of grazing beef cattle....

Lyons, Robert K.; Machen, Richard V.; Stuth, Jerry W.

2000-08-18

132

Foraging Experiences with Children  

ERIC Educational Resources Information Center

Provided are foraging experiences and wild foods information for utilization in the urban school curriculum. Food uses are detailed for roses, dandelions, wild onions, acorns, cattails, violets and mints. (BT)

Russell, Helen Ross

1976-01-01

133

Foraging search: Prototypical intelligence  

NASA Astrophysics Data System (ADS)

We think because we eat. Or as Descartes might have said, on a little more reflection, "I need to eat, therefore I think." Animals that forage for a living repeatedly face the problem of searching for a sparsely distributed resource in a vast space. Furthermore, the resource may occur sporadically and episodically under conditions of true uncertainty (nonstationary, complex and non-linear dynamics). I assert that this problem is the canonical problem solved by intelligence. It's solution is the basis for the evolution of more advanced intelligence in which the space of search includes that of concepts (objects and relations) encoded in cortical structures. In humans the conscious experience of searching through concept space we call thinking. The foraging search model is based upon a higher-order autopoeitic system (the forager) employing anticipatory processing to enhance its success at finding food while avoiding becoming food or having accidents in a hostile world. I present a semi-formal description of the general foraging search problem and an approach to its solution. The latter is a brain-like structure employing dynamically adaptive neurons. A physical robot, MAVRIC, embodies some principles of foraging. It learns cues that lead to improvements in finding targets in a dynamic and nonstationary environment. This capability is based on a unique learning mechanism that encodes causal relations in the neural-like processing element. An argument is advanced that searching for resources in the physical world, as per the foraging model, is a prototype for generalized search for conceptual resources as when we think. A problem represents a conceptual disturbance in a homeostatic sense. The finding of a solution restores the homeostatic balance. The establishment of links between conceptual cues and solutions (resources) and the later use of those cues to think through to solutions of quasi-isomorphic problems is, essentially, foraging for ideas. It is a quite natural extension of the fundamental foraging model.

Mobus, George

2000-05-01

134

7 CFR 1437.401 - Forage.  

Code of Federal Regulations, 2014 CFR

...of determining a payment factor. (e) Small grain forage is the specific acreage of wheat, barley, oats, triticale, or rye intended for use as forage. Small grain forage shall be considered separate crops and distinct from any other forage...

2014-01-01

135

7 CFR 1437.401 - Forage.  

Code of Federal Regulations, 2011 CFR

...of determining a payment factor. (e) Small grain forage is the specific acreage of wheat, barley, oats, triticale, or rye intended for use as forage. Small grain forage shall be considered separate crops and distinct from any other forage...

2011-01-01

136

Computer-Aided Evaluation of Forage Management: Forage Manager.  

ERIC Educational Resources Information Center

Presents the Forage Manager spreadsheet, developed as a forage management teaching tool to integrate agronomic, livestock, and cost data to demonstrate the impact of forage management on livestock production costs. Teaching applications, examples involving agronomic data and conventional agronomic evaluation, and limitations of the program are…

Panciera, M. T.; And Others

1993-01-01

137

Nearshore fish assemblages associated with introduced predatory fishes in lakes  

E-print Network

Micropterus salmoides, pike Esox lucius, rock bass Ambloplites rupestris, smallmouth bass Micropterus dolomieu piscivores introduced outside their native ranges (e.g. largemouth bass Micropterus salmoides, pike Esox lucius, rock bass Ambloplites rupestris, smallmouth bass Micropterus dolomieu, and walleye Sander vitreus

Ricciardi, Anthony

138

C. R. Biologies 332 (2009) 741746 Ecology / cologie  

E-print Network

± SE = 4.2 ± 0.1) compared to other predatory fish such as the native pike (Esox lucius, TP = 3.7 ± 0 brochet (Esox lucius, TP = 3,7 ± 0,1) ou le silure (Silurus glanis, TP = 3,8 ± 0,1). La plupart des études

Cucherousset, Julien

139

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research  

E-print Network

of catch-and-release angling on northern pike (Esox lucius L.) Robert Arlinghausa,b, , Thomas Klefotha, catch-and-release related stressors using a combined laboratory and field study in northern pike (Esox lucius L.). A labora- tory experiment was conducted to investigate the recovery dynamics of physiological

Cooke, Steven J.

140

Optimal Foraging in Semantic Memory  

ERIC Educational Resources Information Center

Do humans search in memory using dynamic local-to-global search strategies similar to those that animals use to forage between patches in space? If so, do their dynamic memory search policies correspond to optimal foraging strategies seen for spatial foraging? Results from a number of fields suggest these possibilities, including the shared…

Hills, Thomas T.; Jones, Michael N.; Todd, Peter M.

2012-01-01

141

Muskie Lunacy: Does the Lunar Cycle Influence Angler Catch of Muskellunge (Esox masquinongy)?  

PubMed Central

We analyzed angling catch records for 341,959 muskellunge (Esox masquinongy) from North America to test for a cyclic lunar influence on the catch. Using periodic regression, we showed that the number caught was strongly related to the 29-day lunar cycle, and the effect was consistent across most fisheries. More muskellunge were caught around the full and new moon than at other times. At night, more muskellunge were caught around the full moon than the new moon. The predicted maximum relative effect was ?5% overall. Anglers fishing exclusively on the peak lunar day would, on average, catch 5% more muskellunge than anglers fishing on random days. On some lakes and at night, the maximum relative effect was higher. We obtained angler effort data for Wisconsin, Mille Lacs (MN), and Lake Vermilion (MN). For Lake Vermilion there was a significant effect of the lunar cycle on angler effort. We could therefore not conclude that the lunar effect on catch was due to an effect on fish behavior alone. Several factors affected the amount of variation explained by the lunar cycle. The lunar effect was stronger for larger muskellunge (>102 cm) than for smaller fish, stronger in midsummer than in June or October, and stronger for fish caught at high latitudes (>48°N) than for fish caught further south. There was no difference in the lunar effect between expert and novice muskellunge anglers. We argue that this variation is evidence that the effect of the lunar cycle on catch is mediated by biological factors and is not due solely to angler effort and reflects lunar synchronization in feeding. This effect has been attributed to variation among moon phases in lunar illumination, but our results do not support that hypothesis for angler-caught muskellunge. PMID:24871329

Vinson, Mark R.; Angradi, Ted R.

2014-01-01

142

Foraging bats avoid noise  

Microsoft Academic Search

SUMMARY Ambient noise influences the availability and use of acoustic information in animals in many ways. While much research has focused on the effects of noise on acoustic communication, here, we present the first study concerned with anthropogenic noise and foraging behaviour. We chose the greater mouse-eared bat (Myotis myotis) as a model species because it represents the especially vulnerable

Andrea Schaub; Joachim Ostwald; Björn M. Siemers

2008-01-01

143

Foraging & Optimality ... economic decisions  

E-print Network

&physiologicalecol ogy 1 Cost-benefit Model · Most often applied to foraging decisions · This type of analysis could 12 #12;· What size should be taken? · Crabs (Carcinus maenas) eating mussels · Profitability (energy profitability · Very large mussels - long h · Very small mussels - low E Prey choice Elner & Hughes. 1978. J

Blouin-Demers, Gabriel

144

Alfalfa for Forage.  

E-print Network

. :lvoid soils inrestet1 with cotton root rot and those with a high population of root knot nematodes. Highly saline soils (those with excessive soluble salts) pre~ent satisfactory alfalfa protluction unless proper internal soil drainage is maintained... alfalfa. Root dis- eases may kill the plants, causing reduced stands and yields. Foliage diseases attack the leaves and stems, lo~trering yield and quality of the forage. Root Diseases Cotto?? root rot. Probably the most destructive alfalfa disease...

Metzer, Robert B.; Lindsay, Kenneth E.; Pratt, J. Neal; Novosad, Albert C.

1972-01-01

145

Learning foraging thresholds for lizards  

SciTech Connect

This work gives a proof of convergence for a randomized learning algorithm that describes how anoles (lizards found in the Carribean) learn a foraging threshold distance. This model assumes that an anole will pursue a prey if and only if it is within this threshold of the anole`s perch. This learning algorithm was proposed by the biologist Roughgarden and his colleagues. They experimentally confirmed that this algorithm quickly converges to the foraging threshold that is predicted by optimal foraging theory our analysis provides an analytic confirmation that the learning algorithm converses to this optimal foraging threshold with high probability.

Goldberg, L.A. [Univ. of Warwick, Coventry (United Kingdom). Dept. of Computer Science; Hart, W.E. [Sandia National Labs., Albuquerque, NM (United States); Wilson, D.B. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

1996-01-12

146

Forage Sorghums in Texas.  

E-print Network

White -4frican Gooseneck Saccaline Saccaline Straight-neck Sourless McLean Atlas Red Amber* Dakota Amber Collier Clubhead 2.15 Leoti 3.12 White African x Sumac White African x Sumac White African .x Sumac White African x Honey White..., and less of both forage and grain at Big Spring. Colman originated as a selection from the progeny of a natural hybrid grom in 1887, whose parents were thought to have been Kansas Orange and Early Amber. Selection by A. A. Denton at the sugar sorghum...

Quinby, John Roy

1934-01-01

147

Forage Breeding and New Varieties  

Technology Transfer Automated Retrieval System (TEKTRAN)

At Agriculture and Agri-Food Canada, the focus of the forage breeding program is to identify and develop novel germplasm and cultivars. The main objective is to produce cultivars with superior persistence, nutritive value and forage yield. This program also emphasizes two other objectives, namely:...

148

What do foraging hummingbirds maximize?  

Microsoft Academic Search

Hainsworth and Wolf (1976) reported that under certain conditions hummingbirds made food choices which did not maximize their net rate of energy intake while foraging. They concluded that the birds were not foraging optimally. We show here that their birds probably maximized a different utility function, the net energy per unit volume consumed (NEVC), which appears to be an optimal

Robert D. Montgomerie; John Mc A. Eadie; Lawrence D. Harder

1984-01-01

149

Forage breeding and new varieties  

Technology Transfer Automated Retrieval System (TEKTRAN)

At Agriculture and Agri-Food Canada, the focus of the forage breeding program is to identify and develop novel germplasm and cultivars. The main objective is to produce cultivars with superior persistence, nutritive value and forage yield. This program also emphasizes two other objectives, namely:...

150

Rainfall Effects on Wilting Forages  

Technology Transfer Automated Retrieval System (TEKTRAN)

Given the uncertainty of the weather and inherent differences between forage crops, specific recommendations for managing potential rain damage to wilting forages are difficult. However, there are a number of principles that can be applied to best manage the potential for rain damage. These science-...

151

Life History of the Colorado Squawfish, Ptychocheilus lucius, and the Colorado Chub, Gila robusta, in the Green River in Dinosaur National Monument, 1964–1966  

Microsoft Academic Search

Investigations of the ecology and life history of the Colorado squawfish, Ptychocheilus lucius, and the Colorado chub, Gila robusta, in the Green River in Dinosaur National Monument, Colorado-Utah, were conducted from May 1964, to October 1966. A total of 1,469 squawfish and 2,393 chubs was collected with gill nets, seines, fry gear, and an electric shocker. The operation of Flaming

C. David Vanicek; Robert H. Kramer

1969-01-01

152

RED-COCKADED WOODPECKER FORAGING BEHAVIOR  

Microsoft Academic Search

We studied Red-cockaded Woodpeckers (Picoides borealis) to examine the effect of status and gender on foraging behavior. Foraging behavior of breeding pairs extended beyond separation by foraging height to include zones (bole, trunk in crown, primary limb, secondary limb) of the tree used and foraging methods (scaling, probing, excavating). Helper males and juvenile females maintained partial spatial separation from breeding

D. CRAIG RUDOLPH; RICHARD N. CONNER; RICHARD R. SCHAEFER; NANCY E. KOERTH

2007-01-01

153

Morphological and molecular evidence of three species of pikes Esox spp. (Actinopterygii, Esocidae) in France, including the description of a new species.  

PubMed

This integrative taxonomy study of French pikes compares morphological characters and molecular sequence data (mitochondrial COI and nuclear Plagl2 genes). In addition to the expected E. lucius, DNA sequences and morphology both support a new species in France, E. aquitanicus sp. nov. from the Charente to the Adour drainages. It is characterized by a color pattern of sides with narrow 1-1.5-scale-wide oblique vertical bands, conferring it a marbled coat, a snout only 0.9 times larger than the postorbital length, an anal fin basis 1.1-1.2 times larger than the caudal peduncle length, 101 to 121 lateral scales, 53 to 57 vertebrae, as well as 24 diagnostic sites in the COI gene and 3 in the Plagl2 gene. Partial COI sequences (131 bp) from modern and historical specimens indicate also the presence of E. cisalpinus and E. lucius during the 19th century in Lake Geneva. Morphological and molecular data points to a possible hybridization between E. lucius with both other local pike species, representing a risk for them. Their endangerment status should be evaluated rapidly in order to take conservation measures. PMID:25242691

Denys, Gaël Pierre Julien; Dettai, Agnès; Persat, Henri; Hautecœur, Mélyne; Keith, Philippe

2014-09-01

154

CROP & SOIL SCIENCES Forage Breeding  

E-print Network

CROP & SOIL SCIENCES Forage Breeding Committee Membership Dr. Joseph Bouton - committee chair Dr. Brian Schwartz Department of Crop & Soil Sciences Department of Crop & Soil Sciences University & Soil Sciences Department of Crop & Soil Sciences University of Georgia University of Georgia Center

Arnold, Jonathan

155

FLOCK SIZE AND FORAGING DECISIONS IN CENTRAL PLACE FORAGING WHITE STORKS, CICONIA CICONIA  

E-print Network

FLOCK SIZE AND FORAGING DECISIONS IN CENTRAL PLACE FORAGING WHITE STORKS, CICONIA CICONIA by JAVIER) Summary We studied the foraging decisions of six individually marked white storks at a breeding colony in central Spain. Storks behaved as central place foragers, gathering in flocks to feed. Travel distance

Carrascal, Luis M.

156

Assessing the benefits of cooperation in honeybee foraging: search costs, forage quality, and competitive ability  

Microsoft Academic Search

The foragers in honeybee colonies cooperate by sharing information about rich sources of food. This study examines three hypotheses about the benefits of this cooperation: (H1) it decreases foragers' costs in finding new food sources, (H2) it increases the quality of the food sources located by foragers, and (H3) it increases the ability of a colony's foragers to compete for

Thomas D. Seeley; P. Kirk Visscher

1988-01-01

157

Ant Foraging Revisited Liviu Alexandru Panait1  

E-print Network

Ant Foraging Revisited Liviu Alexandru Panait1 and Sean Luke1 1. Department of Computer Science: lpanait@cs.gmu.edu Abstract Previous artificial (non-biological) ant foraging models have to date relied ants with the knowledge of the nest direction. In contrast, the work presented solves ant foraging

Luke, Sean

158

Nocturnal foraging in the American White Pelican  

Microsoft Academic Search

Nocturnal foraging was examined in American White Pelicans (Pelecanus erythrorhynchos) at the Dauphin River, about 50 km from a breeding colony on Lake Winnipeg, Manitoba, Canada. From two to three times as many pelicans foraged at night as in the daytime, with foraging flocks being larger at night. In contrast, more pelicans were present at adjacent loafing sites during the

BLAIR F. MCMAHON; ROGER M. EVANS

1992-01-01

159

Spring Cereal Forages By David Wichman  

E-print Network

higher dryland forage yields compared to oats, emmer and spelt (Table 2). Also, barley forage is generally higher in feed value than emmer, oats, spelt and wheat (Table 3). Using oats as cereal forage is discouraged because oats typically has higher nitrate content. Plus oats have higher ADF and NDF values than

Maxwell, Bruce D.

160

Foraging task specialisation and foraging labour allocation in stingless bees  

Microsoft Academic Search

Social bees collect nectar and pollen from flowering plants for energy of the adult bees and for feeding the larvae in the colony. The flowering patterns of plants imply that periods of high food availability are often followed by periods of meagre foraging conditions. Being dependent on such a dynamic food source may have serious implications for the survival of

Frouke Elisabeth Hofstede

2006-01-01

161

An important facet of species interactions is communication through sensory signals, which can be mechanical, electrical,  

E-print Network

present in the damaged tissue of conspecifics cause salamanders, Ambystoma macrodactylum, to avoid areas (northern pike, Esox lucius) or an injured conspecific cause odonate larvae, Enallagma boreale, to change

Moore, Paul A.

162

Retention of Floy FD-94 Anchor Tags and Effect on Growth and Condition of Northern Pike and Largemouth Bass  

E-print Network

and October 1995.315 largemouth bass (Micropterus salmoides) and 170 northern pike (Esox lucius) were captured on growth and condition have been estimated for largemouth bass (Micropterus sa/moides; Wilbur and Duchrow

163

Selective Predation by Three Esocids: The Role of Prey Behavior and Morphology  

Microsoft Academic Search

We documented differential vulnerability of fathead minnows Pimephales promelas, gizzard shad Dorosoma cepedianum. and bluegills Lepomis macrochirus to predation by muskel- lunge Esox masquinongy. northern pike E. lucius. and tiger muskellunge £\\

DAVID H. WAHL; ROY A. STEIN

1988-01-01

164

This article was downloaded by: [University of Wisconsin -Madison] On: 28 May 2013, At: 05:28  

E-print Network

Wisconsin. Muskellunge Esox masquinongy, black bass (i.e., Smallmouth Bass Micropterus dolomieu and Largemouth Bass M. salmoides), Northern Pike E. lucius, Walleye Sander vitreus, and panfish were released

165

I. Fish..........................................................................................................................................2 A) Fish native to both Europe and North America (not analyzed) ........................................2  

E-print Network

autumnalis 2. Esox lucius 3. Gasterosteus aculeatus 4. Lampetra richardsoni 5. Lethenteron japonicum 6. Lota lota 7. Petromyzon marinus 8. Pungitius pungitius 9. Salmo salar 10. Salvelinus alpinus 11. Stenodus

Jeschke, Jonathan

166

DISSOLVED OXYGEN, TEMPERATURE, SURVIVAL OF YOUNG AT FISH SPAWNING SITES  

EPA Science Inventory

Fluctuations of dissolved oxygen concentrations and water temperatures in their natural spawning sites were measured during embryo through larva stages of northern pike (Esox lucius), and during embryo and sac larva stages of bluegills (Lepomis macrochirus) and pumpkinseeds (Lepo...

167

Breeding for increased forage quality  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage crops have a large number of benefits to society, including ecosystem services such as soil and water conservation, wildlife habitat, and diversification of the agricultural landscape. However, their principal function can only be realized when they are processed through livestock to produce ...

168

Squirrel Foraging Preferences: Gone Nuts?  

ERIC Educational Resources Information Center

This field exercise examines the feeding preferences of Gray Squirrels ("Sciurus carolinensis"). Students present squirrels with a variety of food types in a cafeteria-style arrangement in order to test hypotheses about foraging preferences. This exercise, which is appropriate for introductory biology, ecology, and animal behavior classes, is…

Darling, Randi A.

2007-01-01

169

Hazardous duty pay and the foraging cost of predation  

Microsoft Academic Search

We review the concepts and research associated with measuring fear and its consequences for foraging. When foraging, animals should and do demand hazardous duty pay. They assess a foraging cost of predation to compensate for the risk of predation or the risk of catastrophic injury. Similarly, in weighing foraging options, animals tradeoff food and safety. The foraging cost of predation

Joel S. Brown; Burt P. Kotler

2004-01-01

170

BREEDING SOYBEANS FOR FORAGE PRODUCTION  

Technology Transfer Automated Retrieval System (TEKTRAN)

At Chazy, NY yields of forage soybeans varied from 14.3 Mg ha-1 to 5.6 Mg ha-1 over three years with CP ranging from 169 g kg-1 to 116 g kg-1 and NDF ranging from 513 g kg-1 to 445 g kg-1. At Ames, IA, IVDMD declined from 700 g kg-1 46 days after planting then increased at seasons end as seed incre...

171

Alfalfa… for Forage and Seed.  

E-print Network

' ........................................................... Alfalfa Cultivation II 1 ; ........................................................................ Weed Control Il i ALFALFA . . . for Forage and Seed ~ E. M. TREW, Extension Agronomist TEXAS A. & M. COLLEGE SYSTEM u*r AND SEED are the most important... may be seeded into a dead stubble of sorghum, Sudan- grass or small grain. If cultivation is necessary to control weeds, use implements that allow shal- low, subsurface tillage with the stubble left on the soil surface. Weedy growth also may...

Trew, E. M.

1957-01-01

172

Geographic profiling and animal foraging.  

PubMed

Geographic profiling was originally developed as a statistical tool for use in criminal cases, particularly those involving serial killers and rapists. It is designed to help police forces prioritize lists of suspects by using the location of crime scenes to identify the areas in which the criminal is most likely to live. Two important concepts are the buffer zone (criminals are less likely to commit crimes in the immediate vicinity of their home) and distance decay (criminals commit fewer crimes as the distance from their home increases). In this study, we show how the techniques of geographic profiling may be applied to animal data, using as an example foraging patterns in two sympatric colonies of pipistrelle bats, Pipistrellus pipistrellus and P. pygmaeus, in the northeast of Scotland. We show that if model variables are fitted to known roost locations, these variables may be used as numerical descriptors of foraging patterns. We go on to show that these variables can be used to differentiate patterns of foraging in these two species. PMID:16263134

Le Comber, Steven C; Nicholls, Barry; Rossmo, D Kim; Racey, Paul A

2006-05-21

173

Social foraging by honeybees: how colonies allocate foragers among patches of flowers  

Microsoft Academic Search

To understand how a colony of honeybees keeps its forager force focussed on rich sources of food, and analysis was made of how the individual foragers within a colony decide to abandon or continue working (and perhaps even recruit to) patches of flowers. A nectar forager grades her behavior toward a patch in response to both the nectar intake rate

Thomas D. Seeley

1986-01-01

174

Living Mulch Forage Yield and Botanical Composition in a Corn-Soybean-Forage Rotation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Managing forages as living mulches during row crop production requires suppressing the forages to produce economical crop yields. The objective of this research was to identify forage plants with varied growth habit, persistence, and yield potential to provide desirable ecosystem functions and high ...

175

Boa constrictor (Boa constrictor): foraging behavior  

USGS Publications Warehouse

Boa constrictor is often referred to as a sit-and-wait or ambush forager that chooses locations to maximize the likelihood of prey encounters (Greene 1983. In Janzen [ed.], Costa Rica Natural History, pp. 380-382. Univ. Chicago Press, Illinois). However, as more is learned about the natural history of snakes in general, the dichotomy between active versus ambush foraging is becoming blurred. Herein, we describe an instance of diurnal active foraging by a B. constrictor, illustrating that this species exhibits a range of foraging behaviors.

Sorrell, G.G.; Boback, M.S.; Reed, R.N.; Green, S.; Montgomery, C.E.; DeSouza, L.S.; Chiaraviglio, M.

2011-01-01

176

The short-term regulation of foraging in harvester ants  

E-print Network

adjust to a decline in the rate of forager return, and thus to a decline in food availability, by slowing a honeybee forager leaves the nest for its next foraging trip is influenced by a variety of interactions

Gordon, Deborah

177

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2011 CFR

...than air-dry forage, the production to count will be adjusted to...forage. (e) Any harvested production from plants growing in the forage will be...the provisions of section 15 (Production Included in Determining...

2011-01-01

178

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2013 CFR

...than air-dry forage, the production to count will be adjusted to...forage. (e) Any harvested production from plants growing in the forage will be...the provisions of section 15 (Production Included in Determining...

2013-01-01

179

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2012 CFR

...than air-dry forage, the production to count will be adjusted to...forage. (e) Any harvested production from plants growing in the forage will be...the provisions of section 15 (Production Included in Determining...

2012-01-01

180

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2010 CFR

...than air-dry forage, the production to count will be adjusted to...forage. (e) Any harvested production from plants growing in the forage will be...the provisions of section 15 (Production Included in Determining...

2010-01-01

181

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2014 CFR

...than air-dry forage, the production to count will be adjusted to...forage. (e) Any harvested production from plants growing in the forage will be...the provisions of section 15 (Production Included in Determining...

2014-01-01

182

BREEDING AND EVALUATION OF FORAGE SOYBEANS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Introduction. The principal use of soybean in the US in the early 1900 was as livestock forage. Soybeans are less expensive to establish than small seeded perennial legume forages and can provide legume protein after winter killing of perennial legumes. Soybean can improve production distribution ...

183

Heating effects on the quality of forage  

Technology Transfer Automated Retrieval System (TEKTRAN)

The negative consequences of baling forages before they are dried adequately are widely known to hay producers. Generally, these responses include molding, spontaneous heating, losses of DM, and other changes in forage quality that are usually quite undesirable. Many changes in nutritive value are r...

184

PERENNIAL FORAGES AS SECOND GENERATION BIOENERGY CROPS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The lignocellulose in forage crops represents a second generation of biomass feedstock for conversion into energy-related end products. Some of the most extensively studied species for cellulosic feedstock production include forages such as switchgrass (Panicum virgatum L.), reed canarygrass (Phalar...

185

Forager Food Sharing Economy: Transfers and Exchangesi)  

Microsoft Academic Search

African forests, and the Kalahari. Although foraging societies did not have a large number of people, foraging society and culture was and is of interest for several reasons. Here was a social and cultural form that was interesting in its own right. The apparent simpligity was an effective counter foil to a view of humans that assumed the existence of

RoBERT C. HuNT; Brandeis Univensity

186

DEMONSTRATION BULLETIN: FORAGER? SPONGE TECHNOLOGY - DYNAPHORE, INC.  

EPA Science Inventory

The Forager? Sponge is an open-celled cellulose sponge incorporating an amine-containing chelating polymer that has selective affinity for dissolved heavy metals in both cationic and anionic states. The Forager? Sponge technology can be utilized to remove and concentrate heavy me...

187

NON-TRADITIONAL FORAGES FOR CENTRAL APPALACHIA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Small ruminant forage research at AFSRC is designed to improve forage and pasture management for small ruminants, especially as related to control of gastrointestinal nematode (GIN) parasites. Alfalfa pasture produced better meat goat weight gains than orchardgrass, but red clover pasture was diff...

188

Differential effects of structural complexity on predator foraging behavior  

Microsoft Academic Search

The choice of predator foraging mode has important consequences for ecological communities. Foraging mode designations are often made on the basis of predator activity, yet activity can be affected by various environmental stimuli independent of changes in foraging mode. Structural complexity can reduce predator activity by either interfering with predator vision and mobility or as part of a foraging mode

Matt J. Michel; Melinda M. Adams

2009-01-01

189

Ungulate foraging strategies: energy maximizing or time minimizing?  

Microsoft Academic Search

Summary 1. Many classical models of ungulate foraging are premised on energy maximization, yet limited empirical evidence and untested currency assumptions make the choice of currency a non-trivial issue. The primary constraints on forage intake of ungulates are forage quality and availability. Using a model that incorporates these two constraints, we predicted the optimal biomass of forage patches for ungulate

Carita M. Bergman; John M. Fryxell; C. Cormack Gates; Daniel Fortin

2001-01-01

190

The impact of weather on kingbird foraging behavior  

Microsoft Academic Search

Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior vary with weather. Foraging characteristics of five additional kingbird species were also examined to assess Fitzpatrick's 1980 generalization that kingbirds (Tyrannus spp.) are aerial hawking specialists. In Eastern Kingbirds, total

1987-01-01

191

Gregarious foraging in barn swallows after the breeding season  

Microsoft Academic Search

Aerial vertebrate foragers, e.g. insectivorous bats, martins and swallows, often show gregarious behavior such as colonial breeding, communal roosting and aggregating behavior during foraging. Studies of gregariousness in aerial foragers have mostly focused on colonial breeding or communal roosting, and only a few intensive studies have dealt with gregariousness during foraging. Here, we report on large and stable aggregations of

Go Fujita; Hiroyoshi Higuchi

2005-01-01

192

Foraging mode, prey chemical discrimination, and phylogeny in lizards  

Microsoft Academic Search

The long-held hypothesis that active foragers should use chemical senses to detect food more than do ambush foragers is verified for lizards. In actively foraging and herbivorous families, tongue-flicking permits sampling of chemicals for detection and identification of prey, but in ambush-foraging families the tongue does not participate even in detection of prey. Because foraging mode and prey chemical discrimination

William E. Cooper

1995-01-01

193

Seasonal range selection in bighorn sheep: conflicts between forage quality, forage quantity, and predator avoidance  

Microsoft Academic Search

Summary  The migratory and foraging behavior of individually marked bighorn ewes (Ovis canadensis) was studied to test the hypothesis that forage quality determined seasonal range selection. Forage quality was monitored\\u000a through analysis of fecal crude protein. Ewes in the study population utilized two distinct ranges differing in elevation\\u000a and possibly predation risk. Pregnant ewes migrated in May from the low-elevation winter

M. Festa-Bianchet

1988-01-01

194

Foraging guilds of North American birds  

NASA Astrophysics Data System (ADS)

We propose a foraging guild classification for North American inland, coastal, and pelagic birds. This classification uses a three-part identification for each guild—major food, feeding substrate, and foraging technique—to classify 672 species of birds in both the breeding and nonbreeding seasons. We have attempted to group species that use similar resources in similar ways. Researchers have identified foraging guilds generally by examining species distributions along one or more defined environmental axes. Such studies frequently result in species with several guild designations. While the continuance of these studies is important, to accurately describe species' functional roles, managers need methods to consider many species simultaneously when trying to determine the impacts of habitat alteration. Thus, we present an avian foraging classification as a starting point for further discussion to aid those faced with the task of describing community effects of habitat change.

de Graaf, Richard M.; Tilghman, Nancy G.; Anderson, Stanley H.

1985-11-01

195

Grass management for forage and seed production  

E-print Network

GRASS MANAGEMENT FOR FORAGE AND SEED PRODUCTION A Thesis by RICHARD JOHN HENDLER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1979 Major... Subject: Agronomy GRASS MANAGEMENT FOR FORAGE AND SEED PRODUCTION A Thesis by RICHARD JOHN HENDLER Approved as to style and content by: (Chairman of Committee) (Head of Department) (Member) Member) August 1979 ABSTRACT Grass Management...

Hendler, Richard John

2012-06-07

196

Japanese Sugar Cane as a Forage Crop.  

E-print Network

BULLETIN NO. 195 AUGUST, 1916 DIVISION OF AGRONOMY JAPANESE SUGAR CANE AS A FORAGE CROP .".: . COLLEGE POSTOFFICE: COLLEGE STATION,. BRAZOS COUNTY, TEXAS AUSTIN, TEXAS VON BOECKMANN-JONES CO 1916 [Blank Page in Original Bulletin] TEXAS... AGRICULTURAL EXPERIMENT STAT10 N BULLETIN NO. 195 AUGUST, 1916 DIVISION OF AGRONOMY JAPANESE SUGAR CANE AS A FORAGE CROP BY A. H. LEIDIGH, B. S., Agronomist, IN CONSULTATION WITH G. T. McNESS, Superintendent, Substation No. 11, Nacogdoches, and H. H...

Leidigh, A. H. (Arthur Henry); McNess, George Thomas; Laude, H. H. (Hilmer Henry)

1916-01-01

197

Aggressive and Foraging Behavioral Interactions Among Ruffe  

Microsoft Academic Search

The ruffe, Gymnocephalus cernuus, is a nonindigenous percid in the Great Lakes. Ruffe are aggressive benthivores and forage over soft substrates. Laboratory studies in pools (100?cm diameter, 15?cm water depth) were conducted to determine whether fish density (low=2, medium=4, high=6 ruffe per pool) changed foraging and aggressive behaviors with a limited food supply of chironomid larvae. All fish densities demonstrated

Jacqueline F. Savino; Melissa J. Kostich

2000-01-01

198

Aggressive and foraging behavioral interactions among ruffe  

USGS Publications Warehouse

The ruffe, Gymnocephalus cernuus, is a nonindigenous percid in the Great Lakes. Ruffe are aggressive benthivores and forage over soft substrates. Laboratory studies in pools (100 cm in diameter, 15 cm water depth) were conducted to determine whether fish density (low = 2, medium = 4, high = 6 ruffe per pool) changed foraging and aggressive behaviors with a limited food supply of chironomid larvae. All fish densities demonstrated a hierarchy based on aggressive interactions, but ruffe were most aggressive at low and high fish densities. Time spent in foraging was lowest at the low fish density. The best forager at the low fish density was the most aggressive individual, but the second most aggressive fish at the medium and high fish density was the best forager and also the one chased most frequently. A medium fish density offered the best energetic benefits to ruffe by providing the lowest ratio of time spent in aggression to that spent foraging. Based on our results, ruffe should grow best at an intermediate density. With high ruffe densities, we would also expect disparity in size as the more aggressive fish are able to garner a disproportionate amount of the resources. Alternatively, as the Great Lakes are a fairly open system, ruffe could migrate out of one area to colonize another as populations exceed optimal densities.

Savino, Jacqueline F.; Kostich, Melissa J.

2000-01-01

199

Behavioural interaction between fish predators and their prey: effects of plant density  

USGS Publications Warehouse

Prey-specific anti-predatory behaviour under different degrees of structural complexity determines foraging success of predators. The behaviour of piscivorous fish (largemouth bass, Micropterus salmoides and northern pike, Esox lucius) and their prey (bluegills, Lepomis macrochirus, and fathead minnows, Pimephales promelas) were quantified in 60-min experiments in laboratory pools (2 multiplied by 4 m in diameter, 0 multiplied by 5 m deep) with artificial vegetation at densities of 0, 50, 250, and 1000 stems/m2. Largemouth bass switched predatory tactics from searching to ambushing as plant density increased whereas northern pike always used ambushing. At high plant density, both predators captured minnows, but not bluegills. Bluegills modified their behaviour more than minnows in response to predators, thereby avoiding predation at high plant densities. Structural complexity alone did not always provide refuge for prey; prey must use the structure to avoid predators. Predators may seek vegetated areas if appropriate, vulnerable prey are present.

Savino, Jacqueline F.; Stein, Roy A.

1989-01-01

200

Interactions of Forage Quality and Physiological State on Forage Intake of Grazing Beef Cows in Autumn  

Technology Transfer Automated Retrieval System (TEKTRAN)

Intake by grazing cattle is affected by quality and availability of forage and by physiological demands, such as lactation and gestation. However, limited information is available on how these factors interact. We tested the hypothesis that autumn forage intake is altered by the interaction of cow...

201

Social foragers adopt a riskier foraging mode in the centre of their groups  

PubMed Central

Foraging in groups provides many benefits that are not necessarily experienced the same way by all individuals. I explore the possibility that foraging mode, the way individuals exploit resources, varies as a function of spatial position in the group, reflecting commonly occurring spatial differences in predation risk. I show that semipalmated sandpipers (Calidris pusilla), a social foraging avian species, tended to adopt a riskier foraging mode in the central, more protected areas of their groups. Central birds effectively used the more peripheral group members as sentinels, allowing them to exploit a wider range of resources within the same group at the same time. This finding provides a novel benefit of living in groups, which may have a broad relevance given that social foraging species often exploit a large array of resources. PMID:24108674

Beauchamp, Guy

2013-01-01

202

7 CFR 407.13 - Group risk plan for forage.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Group risk plan for forage. 407.13 Section 407...CORPORATION, DEPARTMENT OF AGRICULTURE GROUP RISK PLAN OF INSURANCE REGULATIONS § 407.13 Group risk plan for forage. The provisions of...

2011-01-01

203

7 CFR 407.13 - Group risk plan for forage.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Group risk plan for forage. 407.13 Section 407...CORPORATION, DEPARTMENT OF AGRICULTURE GROUP RISK PLAN OF INSURANCE REGULATIONS § 407.13 Group risk plan for forage. The provisions of...

2013-01-01

204

7 CFR 407.13 - Group risk plan for forage.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Group risk plan for forage. 407.13 Section 407...CORPORATION, DEPARTMENT OF AGRICULTURE GROUP RISK PLAN OF INSURANCE REGULATIONS § 407.13 Group risk plan for forage. The provisions of...

2012-01-01

205

A properly adjusted forage harvester can save time and money  

Technology Transfer Automated Retrieval System (TEKTRAN)

A properly adjusted forage harvester can save fuel and increase the realizable milk per ton of your silage. This article details the adjustments necessary to minimize energy while maximizing productivity and forage quality....

206

Introduction Forager honeybees (Apis mellifera) perform complex and  

E-print Network

421 Introduction Forager honeybees (Apis mellifera) perform complex and highly controlled motor about the absolute profitability of its own source, both the probability Apis mellifera bees perform and successful foraging. Key words: Apis mellifera, dance behaviour, trophallaxis, colony's nectar influx

Menzel, Randolf - Institut für Biologie

207

Female degus ( Octodon degus ) monitor their environment while foraging socially  

Microsoft Academic Search

Vigilance or scanning involves interruptions in foraging behavior when individuals lift their heads and conduct visual monitoring\\u000a of the environment. Theoretical considerations assume that foraging with the “head down”, and scanning (“head up”) are mutually\\u000a exclusive activities, such that foraging precludes vigilance. We tested this generalization in a socially foraging, small\\u000a mammal model, the diurnal Chilean degu (Octodon degus). We

Verónica Quirici; Rodrigo A. Castro; Javiera Oyarzún; Luis A. Ebensperger

2008-01-01

208

Spatiotemporal chemotactic model for ant foraging  

NASA Astrophysics Data System (ADS)

In this paper, we present a generic theoretical chemotactic model that accounts for certain emergent behaviors observed in ant foraging. The model does not have many of the constraints and limitations of existing models for ants colony dynamics and takes into account the distinctly different behaviors exhibited in nature by ant foragers in search of food and food ferrying ants. Numerical simulations based on the model show trail formation in foraging ant colonies to be an emergent phenomenon and, in particular, replicate behavior observed in experiments involving the species P. megacephala. The results have broader implications for the study of randomness in chemotactic models. Potential applications include the developments of novel algorithms for stochastic search in engineered complex systems such as robotic swarms.

Ramakrishnan, Subramanian; Laurent, Thomas; Kumar, Manish; Bertozzi, Andrea L.

2014-12-01

209

Honeybee foraging in differentially structured landscapes.  

PubMed Central

Honeybees communicate the distance and location of resource patches by bee dances, but this spatial information has rarely been used to study their foraging ecology. We analysed, for the first time to the best of the authors' knowledge, foraging distances and dance activities of honeybees in relation to landscape structure, season and colony using a replicated experimental approach on a landscape scale. We compared three structurally simple landscapes characterized by a high proportion of arable land and large patches, with three complex landscapes with a high proportion of semi-natural perennial habitats and low mean patch size. Four observation hives were placed in the centre of the landscapes and switched at regular intervals between the six landscapes from the beginning of May to the end of July. A total of 1137 bee dances were observed and decoded. Overall mean foraging distance was 1526.1 +/- 37.2 m, the median 1181.5 m and range 62.1-10037.1 m. Mean foraging distances of all bees and foraging distances of nectar-collecting bees did not significantly differ between simple and complex landscapes, but varied between month and colonies. Foraging distances of pollen-collecting bees were significantly larger in simple (1743 +/- 95.6 m) than in complex landscapes (1543.4 +/- 71 m) and highest in June when resources were scarce. Dancing activity, i.e. the number of observed bee dances per unit time, was significantly higher in complex than in simple landscapes, presumably because of larger spatial and temporal variability of resource patches in complex landscapes. The results facilitate an understanding of how human landscape modification may change the evolutionary significance of bee dances and ecological interactions, such as pollination and competition between honeybees and other bee species. PMID:12769455

Steffan-Dewenter, Ingolf; Kuhn, Arno

2003-01-01

210

' SNAG CONDITION AND WOODPECKER FORAGING ECOLOGY IN A BOTTOMLAND  

Microsoft Academic Search

we studied woodpecker foraging behavior, snag quality, and surrounding habitat in a bottomland hardwood forest in the Stephen F. Austin Experimental Forest from December 1984 through November 1986. The amount and location of woodpecker foraging excavations indicated that woodpeckers excavated mainly at the well-decayed tops and bases of snags. Woodpeckers preferred to forage on oaks (Quercus spp.) (snags and live

Stephen F. Austin

211

Long-term foraging optimization in northern shovelers  

Microsoft Academic Search

In this paper I attempt to explain the seasonal foraging strategy employed by male northern shovelers (Anas clypeata). Through the use of dynamic-optimization modeling I demonstrate that male shovelers are optimizing total foraging time over the entire summer by foraging heavily when resources (cladocerans) are abundant and utilizing endogenous reserves during times when resources are in short supply. Additionally, I

Paul J. DuBowy

1997-01-01

212

Do cattle egrets gain information from conspecifics when foraging?  

Microsoft Academic Search

We examined whether individual cattle egrets (Bubulcus ibis) base their decisions of where to forage, and how long to stay in a patch, on the behavior of other flock members. Cattle egrets commonly forage in flocks associated with cattle and capture prey at higher rates when they do not share a cow with another egret. Foraging egrets provide cues of

Karen J. Metz; Kent A. Prior; Mark L. Mallory

1991-01-01

213

Ant Foraging Revisited Liviu A. Panait and Sean Luke  

E-print Network

Ant Foraging Revisited Liviu A. Panait and Sean Luke George Mason University, Fairfax, VA 22030 lpanait@cs.gmu.edu, sean@cs.gmu.edu Abstract Most previous artificial ant foraging algorithms have to date the artificial ants with the knowledge of the nest direction. In contrast, the work presented solves ant foraging

Turk, Greg

214

Ant Foraging Revisited Liviu A. Panait and Sean Luke  

E-print Network

Ant Foraging Revisited Liviu A. Panait and Sean Luke George Mason University, Fairfax, VA 22030 lpanait@cs.gmu.edu, sean@cs.gmu.edu Abstract Most previous artificial ant foraging models have to date re the artificial ants with the knowledge of the nest direction. In contrast, the work presented solves ant foraging

George Mason University

215

Density-dependent foraging effort of Deer Mice (Peromyscus maniculatus)  

Microsoft Academic Search

Summary 1. Little is known about how population density affects the foraging behaviour of individuals. Simple models are developed to predict the net effect of density on the quitting-harvest rates of optimal foragers. The theory was tested with experiments that measured the foraging behaviour of free-ranging Deer Mice under control and reduced densities. 2. An increased density of conspecifics may

D. L. Davidson; D. W. Morris

2001-01-01

216

VARIABILITY IN RELATIONSHIPS AMONG FORAGE INTAKE, DIGESTIBILITY, NDF, AND ADF  

Technology Transfer Automated Retrieval System (TEKTRAN)

Confusion exists about forage quality and in methods to measure or predict forage quality. The conventional wisdom is that there are close relationships between voluntary forage dry matter intake (DMI) and digestible dry matter (DDM) concentration, DMI and NDF, and DDM and ADF. Correlation coeffic...

217

Loggerhead Shrike (Lanius ludovicianus L) Foraging Patch and Perch Selection  

Microsoft Academic Search

Loggerhead shrikes have disappeared across much of their former range, most likely due to habitat loss. I studied the habitat shrikes prefer for foraging. Shrikes forage from a perch on prey that they see in the surrounding vegetation. When I mowed the vegetation on one side of selected perches, shrikes strongly preferred to forage on the mowed side even though

Miles Becker

2006-01-01

218

Information flow and organization of stingless bee foraging  

Microsoft Academic Search

Stingless bees (Hymenoptera, Apidae, Meliponini) live in populous permanent colonies and face the same problem as other foraging social insects: how to coordinate the worker's actions and respond to the spatio-temporal uncertainties of food availability in their habitat. Here we review the (social) information used by individual foragers and how organized collective foraging emerges from the individual actions. We also

Jacobus C. Biesmeijer; E. Judith Slaa

2004-01-01

219

Planting Winter Rye after Corn Silage: Managing for Forage  

E-print Network

Planting Winter Rye after Corn Silage: Managing for Forage Factors Affecting Rye Forage Yield and Quality Planting: Rye should be planted as soon after corn silage harvest as possible. In southern Wisconsin, rye planted in mid-to-late September produces higher forage yield, and tends to mature slightly

Balser, Teri C.

220

Intake and digestibility of four forages by Ilamas and sheep  

E-print Network

Intake and digestibility of four forages by Ilamas and sheep R Cordesse M Inesta, JL Gaubert ENSA of llamas to ingest and digest forages. We measured these capacities on 4 forages in comparison with sheep. The digestibility was measured by total col- lection of feces on the last 10 days of each period. Sheep had

Paris-Sud XI, Université de

221

DUSKY DOLPHIN (LAGENORHYNCHUS OBSCURUS) FORAGING IN TWO DIFFERENT  

E-print Network

groupings dusky dolphins forage. Key words: foraging strategy, scattering layer, behavior, acoustic surveyDUSKY DOLPHIN (LAGENORHYNCHUS OBSCURUS) FORAGING IN TWO DIFFERENT HABITATS: ACTIVE ACOUSTIC DETECTION OF DOLPHINS AND THEIR PREY KELLY J. BENOIT-BIRD Hawaii Institute of Marine Biology and Department

Benoit-Bird, Kelly J.

222

Original article Nectar foraging by stingless bees in Costa Rica  

E-print Network

Original article Nectar foraging by stingless bees in Costa Rica: botanical and climatological and Melipona fas- ciata, was studied in Costa Rica. In the humid forest environment M. beecheii collected more foraging / sugar concentration / pollen analysis / Costa Rica 1. INTRODUCTION The nectar foraging community

Paris-Sud XI, Université de

223

DO WINTERING HARLEQUIN DUCKS FORAGE NOCTURNALLY AT HIGH LATITUDES?  

Microsoft Academic Search

We monitored radio-tagged Harlequin Ducks (Histrionicus histrionicus) to determine whether nocturnal feeding was part of their foraging strategy during winter in south-central Alaska. Despite attri- butes of our study site (low ambient temperatures, harsh weather, short day length) and study species (small body size, high daytime foraging rates) that would be expected to favor nocturnal foraging, we found no evidence

Daniel J. Rizzolo; Daniel Esler; Daniel D. Roby; Robert L. Jarvis

2005-01-01

224

PATCH SHAPE, CONNECTIVITY, AND FORAGING BY OLDFIELD MICE (PEROMYSCUS POLIONOTUS)  

E-print Network

PATCH SHAPE, CONNECTIVITY, AND FORAGING BY OLDFIELD MICE (PEROMYSCUS POLIONOTUS) JOHN L. ORROCK, USA We examined how corridors and patch shape affect foraging by the oldfield mouse (Peromyscus: corridor, edge, foraging, giving-up density, Peromyscus polionotus, Savannah River Site Corridors

Haddad, Nick

225

MONITORING THE PRESENCE OF ERGOT ALKALOIDS IN FORAGE ANIMAL SAMPLES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Novel Aspect Initial liquid chromatography tandem mass spectrometry method development for metabolite profiling of ergot alkaloids consumed by forage animals Introduction The presence of ergot alkaloids in forages has been reported to produce acute toxicity when consumed by forage animals. A meth...

226

Original article The foraging behaviour of honey bees  

E-print Network

Original article The foraging behaviour of honey bees (Apis mellifera L) and bumble bees (Bombus — The behaviour of honey bees and bumble bees while foraging on cultivated cranberry in southeastern Massachusetts was studied. Bumble bees were much more consistent foragers than are honey bees

Paris-Sud XI, Université de

227

Predator foraging behaviour drives food-web topological structure  

Microsoft Academic Search

Summary 1. The structure and dynamics of prey populations are shaped by the foraging behaviours of their predators. Yet, there is still little documentation on how distinct predator foraging types control biodiversity, food-web architecture and ecosystem functioning. 2. We experimentally compared the effects of model fish species of two major foraging types of lake planktivores: a size-selective visual feeder (bluegill),

Xavier Lazzaro; Gérard Lacroix; Benoît Gauzens; Jacques Gignoux; Stéphane Legendre

2009-01-01

228

Metabolomics of forage plants: a review  

PubMed Central

Background Forage plant breeding is under increasing pressure to deliver new cultivars with improved yield, quality and persistence to the pastoral industry. New innovations in DNA sequencing technologies mean that quantitative trait loci analysis and marker-assisted selection approaches are becoming faster and cheaper, and are increasingly used in the breeding process with the aim to speed it up and improve its precision. High-throughput phenotyping is currently a major bottle neck and emerging technologies such as metabolomics are being developed to bridge the gap between genotype and phenotype; metabolomics studies on forages are reviewed in this article. Scope Major challenges for pasture production arise from the reduced availability of resources, mainly water, nitrogen and phosphorus, and metabolomics studies on metabolic responses to these abiotic stresses in Lolium perenne and Lotus species will be discussed here. Many forage plants can be associated with symbiotic microorganisms such as legumes with nitrogen fixing rhizobia, grasses and legumes with phosphorus-solubilizing arbuscular mycorrhizal fungi, and cool temperate grasses with fungal anti-herbivorous alkaloid-producing Neotyphodium endophytes and metabolomics studies have shown that these associations can significantly affect the metabolic composition of forage plants. The combination of genetics and metabolomics, also known as genetical metabolomics can be a powerful tool to identify genetic regions related to specific metabolites or metabolic profiles, but this approach has not been widely adopted for forages yet, and we argue here that more studies are needed to improve our chances of success in forage breeding. Conclusions Metabolomics combined with other ‘-omics’ technologies and genome sequencing can be invaluable tools for large-scale geno- and phenotyping of breeding populations, although the implementation of these approaches in forage breeding programmes still lags behind. The majority of studies using metabolomics approaches have been performed with model species or cereals and findings from these studies are not easily translated to forage species. To be most effective these approaches should be accompanied by whole-plant physiology and proof of concept (modelling) studies. Wider considerations of possible consequences of novel traits on the fitness of new cultivars and symbiotic associations need also to be taken into account. PMID:22351485

Rasmussen, Susanne; Parsons, Anthony J.; Jones, Christopher S.

2012-01-01

229

ADAPTIVENESS OF CATTLE EGRET'S (BUBULCUS IBIS) FORAGING  

Microsoft Academic Search

Cattle Egrets (Bubulcus ibis) feeding in close association with cattle catch insect prey at a significantly higher rate and expend less energy than do those foraging alone. Cattle Egrets once had a strong association with grazing cattle, but have now shifted themselves behind tractors specially in inundated agricultural fields. Captures per minute were 2.06 for the egrets feeding near the

Aeshita Mukherjee

2000-01-01

230

SWITCHGRASS FOR BIOFUEL, FORAGE, AND MUSHROOMS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Switchgrass (Panicum virgatum L.), a native perennial warm-season grass, is used as a forage and conservation plant in the eastern USA. During the last 15 years switchgrass has received much attention as a model energy crop. Attributes of switchgrass desirable for bioenergy cropping include its demo...

231

Memory dynamics and foraging strategies of honeybees  

Microsoft Academic Search

Summary The foraging behavior of a single bee in a patch of four electronic flower dummies (feeders) was studied with the aim of analyzing the informational components in the choice process. In different experimental combinations of reward rates, color marks, odors and distances of the feeders, the behavior of the test bee was monitored by a computer in real time

Uwe Greggers; Randolf Menzel

1993-01-01

232

DIEL FORAGING ACTIVITY OF AMERICAN EELS,  

E-print Network

DIEL FORAGING ACTIVITY OF AMERICAN EELS, ANGUILLA ROSTRATA (LESUEUR), IN A RHODE ISLAND ESTUARY Although the American eel, Anguilla rostrata (LeSueur), is abundant and commercially exploited along Veen et aI. 1976; Westin and Nyman 1979), that American eel locomotor activity is noc- turnal

233

Research Investment in "Other" Forage Legumes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Legumes are unique among forages in that they generally have two major advantages compared to grasses: 1) they can fix significant amounts of atmospheric N, thereby precluding the need for fossil-fuel-energy consuming synthetic N fertilizers; and 2) they allow more efficient animal production throug...

234

BLUE WHALE-SIZED MOUTHFULS MAKE FORAGING  

E-print Network

Inside JEB i BLUE WHALE-SIZED MOUTHFULS MAKE FORAGING SUPER EFFICIENT When a blue whale dives from the University of British Columbia, Canada, explains that blue whales may be able to dive, measuring the energetics of blue whale lunges at depth seemed almost impossible until Shadwick and his

Martin, Paul R.

235

EVALUATING FORAGE QUALITY OF GRAZING CATTLE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Providing mother cows with an adequate supply of high quality forage is a difficult task in much of Florida and the Gulf Coast despite the rather mild winters. Many folks in the north, including the author before he came to Florida, have the idea that cattlemen in the region have abundant green gra...

236

ALFALFA: FORAGE CROP OF THE FUTURE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alfalfa hay and silage support dairy, beef, sheep, and horse production in the U.S., as well as a growing export market. Alfalfa is relatively low in fiber and high in protein compared to other forages and typically results in high intakes and levels of milk production. In addition to its excellent...

237

Nitrates and Prussic Acid in Forages  

E-print Network

When nitrates and prussic acid accumulate in forage, the feed may not be safe for livestock consumption. Learn the symptoms of nitrate and prussic acid poisoning and which plants are most likely to pose a risk to livestock. Also learn sampling...

Provin, Tony; Pitt, John L.

2003-01-06

238

The Dynamics of Infant Visual Foraging  

ERIC Educational Resources Information Center

Human infants actively forage for visual information from the moment of birth onward. Although we know a great deal about how stimulus characteristics influence looking behavior in the first few postnatal weeks, we know much less about the intrinsic dynamics of the behavior. Here we show that a simple stochastic dynamical system acts…

Robertson, Steven S.; Guckenheimer, John; Masnick, Amy M.; Bacher, Leigh F.

2004-01-01

239

Field and Forage Crop Pests. MEP 310.  

ERIC Educational Resources Information Center

As part of a cooperative extension service series by the University of Maryland, this publication introduces the identification and control of common agricultural pests that can be found in field and forage crops. The first of the five sections defines "pest" and "weed" and generally introduces different kinds of pests in the categories of…

Morgan, Omar, D.; And Others

240

REGISTRATION OF 'ATLAS BMR-12' FORAGE SORGHUM  

Technology Transfer Automated Retrieval System (TEKTRAN)

‘Atlas bmr-12’ forage sorghum [Sorghum bicolor (L.) Moench] was developed jointly by the USDA, ARS and the University of Nebraska, and was released in January 2005. Atlas bmr-12 closely resembles Atlas. Like Atlas, it did not restore fertility in A1 cytoplasmic male-sterile lines under greenhouse co...

241

MODELING THE FORAGING HABITAT OF HUMPBACK WHALES  

E-print Network

MODELING THE FORAGING HABITAT OF HUMPBACK WHALES by Luciano Dalla Rosa B.Sc. in Oceanography of their home range by modeling encounter rates of humpback whales (Megaptera novaeangliae) in relation, and the Bransfield and Gerlache Straits, Antarctica. Humpback whales in British Columbia were strongly associated

242

Name ___________________________________________ Soil, Water and Forage Testing Laboratory  

E-print Network

Solids $28 per sample (pH, conductivity, N, P, K, Ca, Mg, S, Na, Fe, Cu, Zn, Mn, B, and % moistureName ___________________________________________ Soil, Water and Forage Testing Laboratory Department of Soil and Crop Sciences Texas AgriLife Extension Service B14 BIOSOLID SAMPLE INFORMATION FORM

243

Name ___________________________________________ Soil, Water and Forage Testing Laboratory  

E-print Network

Department of Soil and Crop Sciences Texas AgriLife Extension Service D-1116 P14 PLANT/FORAGE SAMPLE to be Fed: Requested (For Lab Use) I.D. (Bermuda, Wheat, Pecan, etc.)(Feed, Hay, Silage or Plant Tissue, Fe Cu, Mn, Zn and B) $18 per sample 4. Protein + Acid Detergent Fiber (ADF) $12 per sample (TDN

244

Diffusion of foraging innovations in the guppy  

Microsoft Academic Search

The way in which novel learned behaviour patterns spread through animal populations remains poorly understood, despite extensive field research and the recognition that such processes play an important role in the behavioural development, social interactions and evolution of many animal species. We conducted a series of controlled diffusions of foraging information in replicate experimental populations of the guppy, Poecilia reticulata.

Simon M. Reader; Kevin N. Laland

2000-01-01

245

Manure: a 'green' approach to forage fertilization  

Technology Transfer Automated Retrieval System (TEKTRAN)

On average, dairy cows excrete twice as much manure as milk. As a result, dairy farmers are faced with finding additional land for manure applications as herd size and/or productivity increase. Manure application before forage seeding is a good practice, as long as the manure is applied at appropria...

246

Forages: The Foundation for Equine Gastrointestinal Health  

Microsoft Academic Search

Horses have evolved over millions of years as grazers, with specialized digestive tracts adapted to digest and utilize diets containing high levels of plant fiber. They are capable of processing large quanti- ties of forage to meet their nutrient demands. In an attempt to maximize growth or productivity, horses are often fed diets that also contain high levels of grains

JOE D. PAGAN

247

Improving forage quality using seedhead management  

Technology Transfer Automated Retrieval System (TEKTRAN)

Controlling seedhead emergence in perennial grass pastures can extend vegetative growth and high leaf:stem ratios to avoid declines in forage quality during the reproductive development of grasses. There are various management tools for controlling the emergence of seedheads. Pastures can be mowed...

248

Regulation of ants' foraging to resource productivity.  

PubMed Central

We investigate the behavioural rule used by ant societies to adjust their foraging response to the honeydew productivity of aphids. When a scout finds a single food source, the decision to lay a recruitment trail is an all-or-none response based on the opportunity for this scout to ingest a desired volume acting as a threshold. Here, we demonstrate, through experimental and theoretical approaches, the generic value of this recruitment rule that remains valid when ants have to forage on multiple small sugar feeders to reach their desired volume. Moreover, our experiments show that when ants decide to recruit nest-mates they lay trail marks of equal intensity, whatever the number of food sources visited. A model based on the 'desired volume' rule of recruitment as well as on experimentally validated parameter values was built to investigate how ant societies adjust their foraging response to the honeydew productivity profile of aphids. Simulations predict that, with such recruiting rules, the percentage of recruiting ants is directly related to the total production of honeydew. Moreover, an optimal number of foragers exists that maximizes the strength of recruitment, this number being linearly related to the total production of honeydew by the aphid colony. The 'desired volume' recruitment rule that should be generic for all ant species is enough to explain how ants optimize trail recruitment and select aphid colonies or other liquid food resources according to their productivity profile. PMID:12908982

Mailleux, Anne-Catherine; Deneubourg, Jean-Louis; Detrain, Claire

2003-01-01

249

Social organization and foraging in emballonurid bats  

Microsoft Academic Search

1.Five species of emballonurid bats (Rhynchonycteris naso, Saccopteryx leptura, Balantiopteryx plicata, Saccopteryx bilineata, and Peropteryx kappleri), were studied in Costa Rica and Trinidad. Stomach contents suggest that prey size generally increases for bat body size, but within these species there is considerable overlap. R. naso, S. leptura, and P. kappleri each appear to be specialized for foraging in a particular

J. W. Bradbury; S. L. Vehrencamp

1976-01-01

250

Perching but not foraging networks predict the spread of novel foraging skills in starlings.  

PubMed

The directed social learning hypothesis suggests that information does not spread evenly through animal groups, but rather individual characteristics and patterns of physical proximity guide the social transmission of information along specific pathways. Network-based diffusion analysis (NBDA) allows researchers to test whether information spreads following a social network. However, the explanatory power of different social networks has rarely been compared, and current models do not easily accommodate random effects (e.g. allowing for individuals within groups to correlate in their asocial solving rates). We tested whether the spread of two novel foraging skills through captive starling groups was affected by individual- and group-level random and fixed effects (i.e. sex, age, body condition, dominance rank and demonstrator status) and perching or foraging networks. We extended NBDA to include random effects and conducted model discrimination in a Bayesian context. We found that social learning increased the rate at which birds acquired the novel foraging task solutions by 6.67 times, and acquiring one of the two novel foraging task solutions facilitated the asocial acquisition of the other. Surprisingly, the spread of task solutions followed the perching rather than the foraging social network. Upon acquiring a task solution, foraging performance was facilitated by the presence of group mates. Our results highlight the importance of considering more than one social network when predicting the spread of information through animal groups. This article is part of a Special Issue entitled: Cognition in the wild. PMID:25178191

Boogert, Neeltje J; Nightingale, Glenna F; Hoppitt, William; Laland, Kevin N

2014-11-01

251

Foraging strategy and predator avoidance behaviour: an intraspecific approach  

NASA Astrophysics Data System (ADS)

Relationships between predator avoidance behaviour (scanning and flocking) and foraging were studied in Calidris alpina, to test predictions regarding the effect of foraging techniques on such behaviours. The scanning hypothesis predicts that individuals with a tactile hunting technique and individuals with a visual hunting technique (both continuous searchers) do not differ in any variable related to scanning behaviour. The flocking hypothesis predicts that visually hunting individuals witl tend to form smaller flocks than tactile-foraging individuals. The two continuous feeding strategies did not differ among individuals in vigilance rate, nor in vigilance time or mean scan duration. However, with respect to flocking behaviour, visual foragers differed from tactile foragers in foraging flock size. The relationships between flocking behaviour and foraging strategy are discussed. The pattern found at the intraspecific level are the same as those found at interspecific level.

Barbosa, Andrés

1997-11-01

252

The Regulation of Ant Colony Foraging Activity without Spatial Information  

PubMed Central

Many dynamical networks, such as the ones that produce the collective behavior of social insects, operate without any central control, instead arising from local interactions among individuals. A well-studied example is the formation of recruitment trails in ant colonies, but many ant species do not use pheromone trails. We present a model of the regulation of foraging by harvester ant (Pogonomyrmex barbatus) colonies. This species forages for scattered seeds that one ant can retrieve on its own, so there is no need for spatial information such as pheromone trails that lead ants to specific locations. Previous work shows that colony foraging activity, the rate at which ants go out to search individually for seeds, is regulated in response to current food availability throughout the colony's foraging area. Ants use the rate of brief antennal contacts inside the nest between foragers returning with food and outgoing foragers available to leave the nest on the next foraging trip. Here we present a feedback-based algorithm that captures the main features of data from field experiments in which the rate of returning foragers was manipulated. The algorithm draws on our finding that the distribution of intervals between successive ants returning to the nest is a Poisson process. We fitted the parameter that estimates the effect of each returning forager on the rate at which outgoing foragers leave the nest. We found that correlations between observed rates of returning foragers and simulated rates of outgoing foragers, using our model, were similar to those in the data. Our simple stochastic model shows how the regulation of ant colony foraging can operate without spatial information, describing a process at the level of individual ants that predicts the overall foraging activity of the colony. PMID:22927811

Prabhakar, Balaji; Dektar, Katherine N.; Gordon, Deborah M.

2012-01-01

253

Behavioural syndrome in a solitary predator is independent of body size and growth rate.  

PubMed

Models explaining behavioural syndromes often focus on state-dependency, linking behavioural variation to individual differences in other phenotypic features. Empirical studies are, however, rare. Here, we tested for a size and growth-dependent stable behavioural syndrome in the juvenile-stages of a solitary apex predator (pike, Esox lucius), shown as repeatable foraging behaviour across risk. Pike swimming activity, latency to prey attack, number of successful and unsuccessful prey attacks was measured during the presence/absence of visual contact with a competitor or predator. Foraging behaviour across risks was considered an appropriate indicator of boldness in this solitary predator where a trade-off between foraging behaviour and threat avoidance has been reported. Support was found for a behavioural syndrome, where the rank order differences in the foraging behaviour between individuals were maintained across time and risk situation. However, individual behaviour was independent of body size and growth in conditions of high food availability, showing no evidence to support the state-dependent personality hypothesis. The importance of a combination of spatial and temporal environmental variation for generating growth differences is highlighted. PMID:22363687

Nyqvist, Marina J; Gozlan, Rodolphe E; Cucherousset, Julien; Britton, J Robert

2012-01-01

254

SEASONAL VARIATION IN THE FORAGING BEHAVIOR OF SOME MIGRATORY WESTERN WOOD WARBLERS  

Microsoft Academic Search

I observed the foraging behavior of four warbler species (Dendroica petechia, Oporornis tolmiei, Geothlypis trichas, and Wilsonia pusilla) in the summer in Wyoming and in the winter in Nayarit, Mxico. Of six variables (absolute foraging height, relative foraging height, vegetation density, horizontal foraging position, feeding method, and foraging substrate) believed to be potentially important in distinguishing the warbler species ecologically,

RICHARD L. HUTTO

255

Foraging Swarms: From Biology to Engineering  

E-print Network

radially, cell-to-cell attractant signals. #12;11 OHIO STATE T . H . E UNIVERSITY Bacterial Swarm Foraging food #12;12 OHIO STATE T . H . E UNIVERSITY Set of bacteria (positions): P(j, k, ) = i (j, k, )|i = 1 Optimization and Control" [5] #12;14 OHIO STATE T . H . E UNIVERSITY 0 10 20 30 0 5 10 15 20 25 30 Bacteria

256

Do wintering Harlequin Ducks forage nocturnally at high latitudes?  

USGS Publications Warehouse

We monitored radio-tagged Harlequin Ducks (Histrionicus histrionicus) to determine whether nocturnal feeding was part of their foraging strategy during winter in south-central Alaska. Despite attributes of our study site (low ambient temperatures, harsh weather, short day length) and study species (small body size, high daytime foraging rates) that would be expected to favor nocturnal foraging, we found no evidence of nocturnal dive-feeding. Signals from eight radio-tagged Harlequin Ducks never exhibited signal loss due to diving during a total of 780 minutes of nocturnal monitoring. In contrast, the same eight birds exhibited signal loss during 62 ?? 7% (SE) of 5-minute diurnal monitoring periods (total of 365 minutes of monitoring). Our results suggest that Harlequin Ducks in south-central Alaska face a stringent time constraint on daytime foraging during midwinter. Harlequin Ducks wintering at high latitudes, therefore, may be particularly sensitive to factors that increase foraging requirements or decrease foraging efficiency.

Rizzolo, D.J.; Esler, Daniel; Roby, D.D.; Jarvis, R.L.

2005-01-01

257

Elk winter foraging at fine scale in Yellowstone National Park  

Microsoft Academic Search

The link between landscape properties and foraging decisions by herbivores remains unclear, but such knowledge is central\\u000a to the understanding of plant–herbivore dynamics. Our goal was to determine whether fine-scale foraging paths of free-ranging\\u000a elk (Cervus canadensis) respond to spatial structure of habitats in Yellowstone National Park. During winter 2002 we gathered elk-foraging information\\u000a by following snow tracks in open

Daniel Fortin; Juan M. Morales; Mark S. Boyce

2005-01-01

258

Echolocation click rates and behavior of foraging Hawaiian spinner dolphins  

Microsoft Academic Search

Groups of spinner dolphins work together to actively aggregate small animals in the deep-scattering layer that serve as their prey. Detailed information on dolphin foraging behavior, obtained with a 200-kHz multibeam sonar (Simrad MS2000), made it possible to correlate echolocation and foraging. Fifty-six groups of spinner dolphins foraging at night within a midwater micronekton sound-scattering layer were observed with the

Kelly J. Benoit-Bird; Whitlow W. L. Au

2001-01-01

259

Brood pheromone stimulates pollen foraging in honey bees ( Apis mellifera )  

Microsoft Academic Search

Foraging and the mechanisms that regulate the quantity of food collected are important evolutionary and ecological attributes\\u000a for all organisms. The decision to collect pollen by honey bee foragers depends on the number of larvae (brood), amount of\\u000a stored pollen in the colony, as well as forager genotype and available resources in the environment. Here we describe how\\u000a brood pheromone

Tanya Pankiw; Robert E. Page Jr; M. Kim Fondrk

1998-01-01

260

Are seabirds foraging for unpredictable resources?  

NASA Astrophysics Data System (ADS)

It is generally assumed that the extreme life history traits of pelagic seabirds, such as low fecundity or slow growth of chicks, result from the difficulties obtaining energy at sea from unpredictable and patchily distributed resources. However, little information on seabird prey distribution and availability exists to sustain this widely accepted hypothesis. Using tracking studies of 68 sub-populations of flying seabirds, I examine whether it is possible to gain information on the predictability of their marine resources. Because prey are clustered from fine to large scale in nested unities, from swarms to patches and concentrations of patches, it is important to take into account spatial scale. In temperate and polar regions, at large and meso-scales, seabirds appear to have a good knowledge of the location and concentrations of patches and generally use a commuting type of trip to reach foraging zones. Predictability appears to be high at large and meso-scales, with individuals from each sub-population heading in a particular direction from the colony to reach favoured habitats of known enhanced productivity such as shelf edges, frontal zones, upwellings. Within these mesoscale features, the animals use an area-restricted search behaviour to search for patches and swarms at finer scales. Using information on foraging site fidelity of individual birds, I show that differences in predictability at coarse scales are related to the distance and time spent foraging, and in particular to the specific types of foraging habitat. Some habitats appear to be more predictable than others: birds return consistently to the same coarse-scale sectors on shelf edges, whereas predictability is low in oceanic waters, even in frontal zones. Preliminary results on tropical species suggest that the environment here is less predictable in tropic than in temperate or polar zones. This review highlights that patchiness and predictability of marine resources are complex notions: predictability is dependent on the spatial and temporal scale considered, and especially on the marine habitat of foraging interest. I discuss the potential consequences of these results for the breeding success and life history of seabirds.

Weimerskirch, Henri

2007-02-01

261

Echolocation click rates and behavior of foraging Hawaiian spinner dolphins  

NASA Astrophysics Data System (ADS)

Groups of spinner dolphins work together to actively aggregate small animals in the deep-scattering layer that serve as their prey. Detailed information on dolphin foraging behavior, obtained with a 200-kHz multibeam sonar (Simrad MS2000), made it possible to correlate echolocation and foraging. Fifty-six groups of spinner dolphins foraging at night within a midwater micronekton sound-scattering layer were observed with the sonar. During sonar surveys, the rates of whistles and echolocation clicks were measured using four hydrophones at 6-m depth intervals. Significant differences in click rates were found between depths and between the different stages of foraging. Groups of foraging dolphins ranged in size from 16 to 28 dolphins. Click rates were not significantly affected by the number of dolphins in a foraging group. Contrary to initial predictions, click rates were relatively low when sonar data indicated that pairs of dolphins were actively feeding. Highest echolocation rates occurred within the scattering layer, during transitions between foraging states. Whistles were only detected when dolphins were not in a foraging formation and when animals were surfacing. This suggests clicks may be used directly or indirectly to cue group movement during foraging.

Benoit-Bird, Kelly J.; Au, Whitlow W. L.

2001-05-01

262

Zoo Biology 6:373-378 (1987) Submarine Foraging Behavior of Alcids in  

E-print Network

Zoo Biology 6:373-378 (1987) Submarine Foraging Behavior of Alcids in an Artificial Environment of the birds' submarine foraging behavior are needed. We report here an initial study of foraging by seven

Duffy, David Cameron

263

Assessing Habitat for Avian Species in Assessing Habitat for Avian Species in an Integrated Forage/Biofuels an Integrated Forage/Biofuels  

E-print Network

in an Integrated Forage/Biofuels an Integrated Forage/Biofuels Management System Management System in the Midin NWSG mixes beneficial to forage, biofuels production, and wildlife habitatp , 3. identify wildlife habitat benefits associated with varying forage and biofuels management strategies 4. identify optimum

Gray, Matthew

264

The impact of weather on kingbird foraging behavior  

SciTech Connect

Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior vary with weather. Foraging characteristics of five additional kingbird species were also examined to assess Fitzpatrick's 1980 generalization that kingbirds (Tyrannus spp.) are aerial hawking specialists. In Eastern Kingbirds, total foraging rate was independent of air temperature, cloud cover, wind speed, and time of day, but the rate of aerial hawking varied directly with air temperature and inversely with cloud cover (both P < 0.05). Effects of the two variables were additive. The percentage of foraging movements that were aerial hawks also increased with temperature and declined with cloud cover, and hover-gleaning and perch-to-ground sallying were observed mainly during cloudy weather. Sally (i.e., foraging flight) distance correlated directly with perch height and air temperature, and large insects were captured almost exclusively in long upward or horizontal flights. I interpret these data to indicate that foraging behavior and the capture of large, flying insects depends on weather because of how it affects the activity of insect prey. Foraging data on kingbirds support Fitzpatrick's generalization, but the relative use of aerial hawking varies considerably among species. Resident Tropical Kingbirds (T. melancholicus) are the most specialized foragers, whereas the migrant and widely distributed Eastern Kingbird appears to be the most generalized. Certain habitats also appear to favor the use of particular foraging methods (e.g., outward striking in grasslands, and perch-to-ground sallying in drier, open habitats).

Murphy, M.T. (Museum of Natural History, The University of Kansas, Lawrence, KS 66045)

1987-01-01

265

Downy woodpecker foraging behavior: foraging by expectation and energy intake rate  

Microsoft Academic Search

I describe an artificial patch system that was used to study the foraging behavior of free-roaming downy woodpeckers (Picoides pubescens) in a woodlot in southeastern Michigan. The artificial “patches” used were thin logs into which were drilled small holes to hold food items (bits of sunflower seed kernels). Downy woodpeckers would systematically search the holes of a patch for food

Steven L. Lima

1983-01-01

266

Perceptual constraints on optimal foraging: The effects of variation among foragers  

Microsoft Academic Search

Summary We present a simple model of habitat selection in which individuals differ in their ability to discriminate between resource sites' profitabilities. The model investigates the effects of violating the ‘ideal’ assumption of the well-known ideal free distribution (IFD). We show that (1) variability in perceptual limits within a population can significantly change the distribution of foraging animals even though

Hamish G. Spencer; Martyn Kennedy; Russell D. Gray

1996-01-01

267

DAFOSYM: A Dairy Forage System Model for Evaluating Alternatives in Forage Conservation1  

Microsoft Academic Search

The dairy forage system model, DAFOSYM, is a simulation model designed to evaluate technologies and management strategies on representa- tive dairy farms. The model integrates crop growth, harvest, storage, feeding, animal utilization, and economic analy- sis. Corn and alfalfa growth are simu- lated using historical weather data. Alfalfa harvest includes mowing, field curing, raking, baling, and chopping; losses and quality

C. Alan Rotz; Dennis R. Buckmaster; David R. Mertens; J. Roy Black

1989-01-01

268

Social foraging in honey bees: how nectar foragers assess their colony's nutritional status  

Microsoft Academic Search

A honey bee colony operates as a tightly integrated unit of behavioral action. One manifestation of this in the context of foraging is a colony's ability to adjust its selectivity among nectar sources in relation to its nutritional status. When a colony's food situation is good, it exploits only highly profitable patches of flowers, but when its situation is poor,

Thomas D. Seeley

1989-01-01

269

Multimodal Floral Signals and Moth Foraging Decisions  

PubMed Central

Background Combinations of floral traits – which operate as attractive signals to pollinators – act on multiple sensory modalities. For Manduca sexta hawkmoths, how learning modifies foraging decisions in response to those traits remains untested, and the contribution of visual and olfactory floral displays on behavior remains unclear. Methodology/Principal Findings Using M. sexta and the floral traits of two important nectar resources in southwestern USA, Datura wrightii and Agave palmeri, we examined the relative importance of olfactory and visual signals. Natural visual and olfactory cues from D. wrightii and A. palmeri flowers permits testing the cues at their native intensities and composition – a contrast to many studies that have used artificial stimuli (essential oils, single odorants) that are less ecologically relevant. Results from a series of two-choice assays where the olfactory and visual floral displays were manipulated showed that naïve hawkmoths preferred flowers displaying both olfactory and visual cues. Furthermore, experiments using A. palmeri flowers – a species that is not very attractive to hawkmoths – showed that the visual and olfactory displays did not have synergistic effects. The combination of olfactory and visual display of D. wrightii, however – a flower that is highly attractive to naïve hawkmoths – did influence the time moths spent feeding from the flowers. The importance of the olfactory and visual signals were further demonstrated in learning experiments in which experienced moths, when exposed to uncoupled floral displays, ultimately chose flowers based on the previously experienced olfactory, and not visual, signals. These moths, however, had significantly longer decision times than moths exposed to coupled floral displays. Conclusions/Significance These results highlight the importance of specific sensory modalities for foraging hawkmoths while also suggesting that they learn the floral displays as combinatorial signals and use the integrated floral traits from their memory traces to mediate future foraging decisions. PMID:23991154

Riffell, Jeffrey A.; Alarcón, Ruben

2013-01-01

270

Complex scaling behavior in animal foraging patterns  

NASA Astrophysics Data System (ADS)

This dissertation attempts to answer questions from two different areas of biology, ecology and neuroscience, using physics-based techniques. In Section 2, suitability of three competing random walk models is tested to describe the emergent movement patterns of two species of primates. The truncated power law (power law with exponential cut off) is the most suitable random walk model that characterizes the emergent movement patterns of these primates. In Section 3, an agent-based model is used to simulate search behavior in different environments (landscapes) to investigate the impact of the resource landscape on the optimal foraging movement patterns of deterministic foragers. It should be noted that this model goes beyond previous work in that it includes parameters such as spatial memory and satiation, which have received little consideration to date in the field of movement ecology. When the food availability is scarce in a tropical forest-like environment with feeding trees distributed in a clumped fashion and the size of those trees are distributed according to a lognormal distribution, the optimal foraging pattern of a generalist who can consume various and abundant food types indeed reaches the Levy range, and hence, show evidence for Levy-flight-like (power law distribution with exponent between 1 and 3) behavior. Section 4 of the dissertation presents an investigation of phase transition behavior in a network of locally coupled self-sustained oscillators as the system passes through various bursting states. The results suggest that a phase transition does not occur for this locally coupled neuronal network. The data analysis in the dissertation adopts a model selection approach and relies on methods based on information theory and maximum likelihood.

Premachandra, Prabhavi Kaushalya

271

Forage polyphenol oxidase and ruminant livestock nutrition  

PubMed Central

Polyphenol oxidase (PPO) is predominately associated with the detrimental effect of browning fruit and vegetables, however, interest within PPO containing forage crops (crops to be fed to animals) has grown since the browning reaction was associated with reduced nitrogen (N) losses in silo and the rumen. The reduction in protein breakdown in silo of red clover (high PPO forage) increased the quality of protein, improving N-use efficiency [feed N into product N (e.g., Milk): NUE] when fed to ruminants. A further benefit of red clover silage feeding is a significant reduction in lipolysis (cleaving of glycerol-based lipid) in silo and an increase in the deposition of beneficial C18 polyunsaturated fatty acid (PUFA) in animal products, which has also been linked to PPO activity. PPOs protection of plant protein and glycerol based-PUFA in silo is related to the deactivation of plant proteases and lipases. This deactivation occurs through PPO catalyzing the conversion of diphenols to quinones which bind with cellular nucleophiles such as protein reforming a protein-bound phenol (PBP). If the protein is an enzyme (e.g., protease or lipase) the complexing denatures the enzyme. However, PPO is inactive in the anaerobic rumen and therefore any subsequent protection of plant protein and glycerol based-PUFA in the rumen must be as a result of events that occurred to the forage pre-ingestion. Reduced activity of plant proteases and lipases would have little effect on NUE and glycerol based-PUFA in the rumen due to the greater concentration of rumen microbial proteases and lipases. The mechanism for PPOs protection of plant protein in the rumen is a consequence of complexing plant protein, rather than protease deactivation per se. These complexed proteins reduce protein digestibility in the rumen and subsequently increase undegraded dietary protein flow to the small intestine. The mechanism for protecting glycerol-based PUFA has yet to be fully elucidated but may be associated with entrapment within PBP reducing access to microbial lipases or differences in rumen digestion kinetics of the forage and therefore not related to PPO activity.

Lee, Michael R. F.

2014-01-01

272

FLIGHT STRATEGIES OF MIGRATING OSPREY: FASTING VS. FORAGING  

Microsoft Academic Search

We developed energetics models to predict migration times and fat consumption rates of osprey (Pandion haliaetus) migrating south from their breeding grounds in the Intermountain West of North America. In these models we simulated three migration strategies: fasting, foraging at several mid-migration stopovers (jump strategy) and frequent foraging at stopovers (hop strategy). Because these piscivores appear to migrate predominantly over

GRADY L. CANDLERAND; PATRICIA L. KENNEDY

273

Original article Lignin-carbohydrate complexes in forages  

E-print Network

Original article Lignin-carbohydrate complexes in forages: structure and consequences in the ruminal degradation of cell-wall carbohydrates A Cornu JM Besle P Mosoni, E Grenet INRA-Theix, Unité) Summary ― Lignin-carbohydrate complexes (LCCS) are recognised as key structures in forage

Boyer, Edmond

274

Estimating the energetic cost of abiotic conditions using foraging behaviour  

E-print Network

Estimating the energetic cost of abiotic conditions using foraging behaviour Sandra J. Webster tshawytscha. Methods: We quantified energetic costs by estimating the quitting harvest rate of juvenile salmon temperatures is very similar. Conclusion: Foraging behaviour can be used to estimate the energetic costs paid

Dill, Lawrence M.

275

Group size and foraging efficiency in yellow baboons  

Microsoft Academic Search

I studied the foraging behaviour of adults in three different-sized groups of yellow baboons (Papio cynocephalus) at Amboseli National Park in Kenya to assess the relationship between group size and foraging efficiency in this species. Study groups ranged in size from 8 to 44 members; within each group, I collected feeding data for the dominant adult male, the highest ranking

Peter B. Stacey

1986-01-01

276

Optimal foraging: Random movement by pollen collecting bumblebees  

Microsoft Academic Search

Two bumblebee species, Bombus bifarius and B. flavifrons, forage randomly with respect to direction when gathering pollen on Potentilla gracilis. Bees avoid revisiting flowers by being able to differentiate recently visited from unvisited flowers. This recognition occurs while bees are flying over open flowers and appears to be a response to the amount of available pollen within flowers. Random foraging

Michael Zimmerman

1982-01-01

277

SHORT COMMUNICATION White Storks, Ciconia ciconia, forage on rubbish dumps  

E-print Network

SHORT COMMUNICATION White Storks, Ciconia ciconia, forage on rubbish dumps in Poland--a novel on the foraging of White Storks on rubbish dumps, a novel behaviour in Central European populations, is presented one to 348 White Storks (median=2, N=116) were observed on rubbish dumps, and most of the records (86

Boyer, Edmond

278

Optimization, conflict, and nonoverlapping foraging ranges in ants.  

PubMed

An organism's foraging range depends on the behavior of neighbors, the dynamics of resources, and the availability of information. We use a well-studied population of the red harvester ant Pogonomyrmex barbatus to develop and independently parameterize models that include these three factors. The models solve for an allocation of foraging ants in the area around the nest in response to other colonies. We compare formulations that optimize at the colony or individual level and those that do or do not include costs of conflict. Model predictions were compared with data collected on ant time budgets and ant density. The strategy that optimizes at the colony level but neglects costs of conflict predicts unrealistic levels of overlap. In contrast, the strategy that optimizes at the individual level predicts realistic foraging ranges with or without inclusion of conflict costs. Both the individual model and the colony model that includes conflict costs show good quantitative agreement with data. Thus, an optimal foraging response to a combination of exploitation and interference competition can largely explain how individual foraging behavior creates the foraging range of a colony. Deviations between model predictions and data indicate that colonies might allocate a larger than optimal number of foragers to areas near boundaries between foraging ranges. PMID:14618533

Adler, Frederick R; Gordon, Deborah M

2003-11-01

279

Testing Optimal Foraging Theory Using Bird Predation on Goldenrod Galls  

ERIC Educational Resources Information Center

All animals must make choices regarding what foods to eat, where to eat, and how much time to spend feeding. Optimal foraging theory explains these behaviors in terms of costs and benefits. This laboratory exercise focuses on optimal foraging theory by investigating the winter feeding behavior of birds on the goldenrod gall fly by comparing…

Yahnke, Christopher J.

2006-01-01

280

Alfalfa forage and seed crop tolerance to flumioxazin  

Technology Transfer Automated Retrieval System (TEKTRAN)

Weed control is an important component of producing high quality and high yielding alfalfa seed and forage. Flumioxazin was evaluated for weed control in alfalfa forage and seed production in 2007 and 2008 in Washington State. Flumioxazin applied at 0.14 and 0.28 kg ai/ha plus paraquat in February t...

281

Factors Affecting Fatty Acid Composition in Forage and Milk  

E-print Network

Factors Affecting Fatty Acid Composition in Forage and Milk Katarina Arvidsson Faculty of Natural in Forage and Milk Abstract The aims of the studies underlying this thesis were to evaluate variations on the FA contents of the milk. Initially, samples of timothy (Phleum pratense L.) were subjected

282

7 CFR 457.151 - Forage seeding crop insurance provisions.  

Code of Federal Regulations, 2010 CFR

...land for replacing of the forage seed and then replacing the forage seed in the insured acreage with the...a normal stand. Replacing new seed into an existing damaged stand...considered replanting. Sales closing date —In lieu of the...

2010-01-01

283

7 CFR 457.151 - Forage seeding crop insurance provisions.  

Code of Federal Regulations, 2011 CFR

...land for replacing of the forage seed and then replacing the forage seed in the insured acreage with the...a normal stand. Replacing new seed into an existing damaged stand...considered replanting. Sales closing date —In lieu of the...

2011-01-01

284

ANIMAL RESPONSES TO CIRCADIAN RHYTHMS IN FORAGE QUALITY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Net photosynthesis and respiration in growing plants cause a circadian rhythm in forage quality. Soluble sugar concentrations increase in plants during the day causing a dilution in ADF and NDF. Herbivores show a strong preference for afternoon (PM) vs morning (AM) harvested forage. Cattle, sheep, g...

285

A Hybrid, Multi-Agent Model of Foraging Bottlenose Dolphins  

E-print Network

replicating foraging dolphin behavior will herd a group of agents replicating fish behavior. The work by MusadA Hybrid, Multi-Agent Model of Foraging Bottlenose Dolphins Musad Haque Amir Rahmani Magnus.rahmani, magnus}@ece.gatech.edu) Abstract: Social behavior of animals can offer solution models for missions

Egerstedt, Magnus

286

Group foraging by a stream minnow: shoals or aggregations?  

USGS Publications Warehouse

The importance of social attraction in the formation of foraging groups was examined for a stream-dwelling cyprinid, the rosyside dace, Clinostomus funduloides. Dace arrivals and departures at natural foraging sites were monitored and tested for (1) tendency of dace to travel in groups, and (2) dependency of arrival and departure rates on group size. Dace usually entered and departed foraging sites independently of each other. Group size usually affected neither arrival rate nor departure probability. Thus, attraction among dace appeared weak; foraging groups most often resulted from dace aggregating in preferred foraging sites. The strongest evidence of social attraction was during autumn, when dace departure probability often decreased with increasing group size, possibly in response to increased threat of predation by a seasonally occurring predator. Dace also rarely avoided conspecifics, except when an aggressive individual defended a foraging site. Otherwise, there was little evidence of exploitative competition among dace for drifting prey or of foraging benefits in groups, because group size usually did not affect individual feeding rates. These results suggest that the benefits of group foraging demonstrated under laboratory conditions in other studies may not always apply to field conditions.

Freeman, M.C.; Grossman, G.D.

1992-01-01

287

Testing Dispersal Hypotheses in Foraging Green Sea Turtles (Chelonia  

E-print Network

with a model of juvenile natal homing impacted by other factors. Effective protection of turtles foraging alongTesting Dispersal Hypotheses in Foraging Green Sea Turtles (Chelonia mydas) of Brazil EUGENIA NARO@amnh.org. Abstract Testing theories of dispersal is challenging in highly migratory species. In sea turtles

DeSalle, Rob

288

ORIGINAL PAPER Time stress, predation risk and diurnalnocturnal foraging  

E-print Network

time stress. Here we test if size-dependent risk and time constraints on feeding affect the foraging stress. Keywords Predation risk . Growth rate . Life history theory. Body size . Seasonal constraintsORIGINAL PAPER Time stress, predation risk and diurnal­nocturnal foraging trade-offs in larval prey

Gotthard, Karl

289

Comparative Sucrose Responsiveness in Apis mellifera and A. cerana Foragers  

PubMed Central

In the European honey bee, Apis mellifera, pollen foragers have a higher sucrose responsiveness than nectar foragers when tested using a proboscis extension response (PER) assay. In addition, Africanized honey bees have a higher sucrose responsiveness than European honey bees. Based on the biology of the Eastern honey bee, A. cerana, we hypothesized that A. cerana should also have a higher responsiveness to sucrose than A. mellifera. To test this hypothesis, we compared the sucrose thresholds of pollen foragers and nectar foragers in both A. cerana and A. mellifera in Fujian Province, China. Pollen foragers were more responsive to sucrose than nectar foragers in both species, consistent with previous studies. However, contrary to our hypothesis, A. mellifera was more responsive than A. cerana. We also demonstrated that this higher sucrose responsiveness in A. mellifera was not due to differences in the colony environment by co-fostering two species of bees in the same mixed-species colonies. Because A. mellifera foragers were more responsive to sucrose, we predicted that their nectar foragers should bring in less concentrated nectar compared to that of A. cerana. However, we found no differences between the two species. We conclude that A. cerana shows a different pattern in sucrose responsiveness from that of Africanized bees. There may be other mechanisms that enable A. cerana to perform well in areas with sparse nectar resources. PMID:24194958

Yang, Wenchao; Kuang, Haiou; Wang, Shanshan; Wang, Jie; Liu, Wei; Wu, Zhenhong; Tian, Yuanyuan; Huang, Zachary Y.; Miao, Xiaoqing

2013-01-01

290

Use of Active Acoustics to Study Fish and its Forage  

E-print Network

Use of Active Acoustics to Study Fish and its Forage Pacific Islands Fisheries Science Center Acoustics · Fisheries Independent ­ Unbiased by fishing location gear type catchability · Predetermined · Schooling patterns and aggregative behavior · Simultaneous data on fish and its forage #12;Active Acoustics

Hawai'i at Manoa, University of

291

A variable-response model for parasitoid foraging behavior  

Microsoft Academic Search

An important factor inducing variability in foraging behavior in parasitic wasps is experience gained by the insect. Together with the insect's genetic constitution and physiological state, experience ultimately defines the behavioral repertoire under specified environmental circumstances. We present a conceptual variable-response model based on several major observations of a foraging parasitoid's responses to stimuli involved in the hostfinding process. These

L. E. M. Vet; W. J. Lewis; D. R. Papaj; J. C. van Lenteren

1990-01-01

292

Coordinating Beef Cattle Management with the Range Forage Resource  

Microsoft Academic Search

Highlight: Seasonal changes in forage production and quality occur due to climatic factors, principally precipitation. Increased eficiency of livestock production could occur if livestock management were coordinated to the changes that occur in forage quality. Traditionally, calves are born in the spring in much of the western United States. Weaning then occurs sometime in late fall. Manage- ment practices of

MARTIN VAVRA; ROBERT J. RALEIGH

293

Animal Foraging and the Evolution of Goal-Directed Cognition  

ERIC Educational Resources Information Center

Foraging-and feeding-related behaviors across eumetazoans share similar molecular mechanisms, suggesting the early evolution of an optimal foraging behavior called area-restricted search (ARS), involving mechanisms of dopamine and glutamate in the modulation of behavioral focus. Similar mechanisms in the vertebrate basal ganglia control motor…

Hills, Thomas T.

2006-01-01

294

Forages for Grazing Animal Health AGRICULTURE IN 2008  

E-print Network

for the enhancement of animal health through natural and ge- netically modified (GM) compounds produced by forage; and isoflavones to mimic estrogenic activity. Genetic transformation of forage plants to express novel bio-active proteins also has potential to impact animal health issues. One exciting possibility is the genetic

295

The hunting handicap: costly signaling in human foraging strategies  

Microsoft Academic Search

Humans sometimes forage or distribute the products of foraging in ways that do not maximize individual energetic return rates. As an alternative to hypotheses that rely on reciprocal altruism to counter the costs of inefficiency, we suggest that the cost itself could be recouped through signal benefit. Costly signaling theory predicts that signals can provide fitness benefits when costs are

Rebecca Bliege Bird; Eric Alden Smith; Douglas W. Bird

2001-01-01

296

ORIGINAL PAPER The effect of ambient temperature on forager sound  

E-print Network

ORIGINAL PAPER The effect of ambient temperature on forager sound production and thoracic­25°C) conditions. We recorded forager sounds under both conditions and tested the effect of temperature 2000; Cameron and Mardulyn 2001), are also able to regulate nest temperature (Kerr and Laidlaw 1956

Nieh, James

297

FUZZY MODEL OF BIRD FLOCK FORAGING Miha Moskon1  

E-print Network

FUZZY MODEL OF BIRD FLOCK FORAGING BEHAVIOR Miha Moskon1 , Frank H. Heppner2 , Miha Mraz1 , Nikolaj for the simulation of bird foraging behavior. The core of the model is based on the fuzzy model for the computer simulation of bird flocking presented by Lebar Bajec et al. The later was extended in such way that allows

Bajec, Iztok Lebar

298

Schooling tendency and foraging benefit in the ocean surgeonfish  

Microsoft Academic Search

Field observations of individuallytagged ocean surgeonfish (Acanthurus bahianus) indicated that schooling provided a foraging benefit: an increase in relative forging time. The magnitude of this increase differed among individuals, primarily due to time budgets of the fish when they were not in schools. The proportion of nonschooling time devoted to foraging was positively correlated with fish size, while the proportion

Nancy G. Wolf

1987-01-01

299

River otter foraging opportunities at a coastal wetland  

E-print Network

River otter foraging opportunities at a coastal wetland Results DiscussionIntroduction River otters that otter activity is probably driven by foraging opportunities, i.e. visiting sites where potential prey are vulnerable and found in abundance. River otters may also readily switch their attention from fish

Johnson, Matthew

300

Protein quality of cottontail rabbit forages following range- land disturbance  

Microsoft Academic Search

Seasonal changes in the botanical composition of diets and pro- tein quality of forages consumed by cottontail rabbits (Sylvilagus floridanus) were monitored on disturbed and undisturbed upland hardwood forest-tallgrass prairies in central Oklahoma Our pri- mary objective was to evaluate the seasonal dynamics of levels of selected amino acid nutrients in forages required for mainte- nance, growth, or reproduction, and

D. G. PEITZ; R. L. LOCHMILLER; D. M. LESLIE; D. M. ENGLE

1997-01-01

301

The development of foraging microhabitat preferences in meerkats  

Microsoft Academic Search

Animals of many species tend to target their foraging attempts toward particular microhabitats within their habitat. Although these preferences are critical determinants of the foraging niche and have important ecological and evolutionary implications, we know little about how they develop. Here, we use detailed longitudinal data from meerkats (Suricata suricatta) to examine how individual learning and the use of social

Alex Thornton; Sarah J. Hodge

2008-01-01

302

Mapping of wood stork foraging habitat with satellite data  

SciTech Connect

Potential foraging sites for an endangered species, the wood stork, were identified using Landsat thematic mapper data for a section of north central Georgia and the Savannah River floodplain swamp in South Carolina. This was accomplished using innovative clustering techniques applied to known wood stork foraging sites around the Birdsville Colony in Georgia. The signatures for known sites were then geographically extended to a 1520-square-kilometer region surrounding the Birdsville Colony. Thematic maps were produced and foraging area acreages computed providing a regional assessment of existing and potential wood stork foraging sites. Approximately 1744 hectarea of potential shallow water and macrophyte foraging habitat were identified in the area surroundings the Birdsville Colony. 14 refs., 3 figs.

Jensen, J.R.; Coulter, M.; Mackey, H.E. Jr.; Hodgson, M.E.

1985-01-01

303

A Constraint Condition for Foraging Strategy in Subterranean Termites  

PubMed Central

Previous studies have explored the relationship between termite branch tunnel geometry and foraging efficiency in a model simulation in which foraging efficiency, ?, for two termite species, Coptotermes formosanus Shiraki and Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), was investigated in response to two variables, the probability of tunnel branching (Pbranch) and the probability of tunnel branch termination (Pterm). It was found that simulated tunnel patterns based on empirical data did not have maximum foraging efficiency. We hypothesized that termites could increase their foraging efficiency in response to landscape heterogeneity. The present study investigated how termites could control the two variables, Pbranch and Pterm, in response to the external environment in terms of tunnel network connectivity. It was found that the best simulated strategy for C. formosanus and R. flavipes termites would occur if both Pbranch and Pterm were increased together. This study provides possible mechanisms for foraging strategies in subterranean termites and a baseline for future empirical work. PMID:21070178

Jeon, Wonju; Kang, Sheon-Young; Su, Nan-Yao; Lee, Sang-Hee

2010-01-01

304

Wood bison population recovery and forage availability in northwestern Canada.  

PubMed

Forage availability was assessed to determine sustainable stocking rates for eight broadly defined vegetation types (Treed Uplands, Treed Lowlands, Mixed Tall Shrub/Sedge, Closed-canopied Willow, and Open-canopied Willow, Meadow, Wetland Grass, Wetland Sedge) for use by wood bison (Bison bison athabascae), a threatened subspecies, in the Canadian boreal forest of northern Alberta. Clip plots (n=108) were used to sample peak availability of herbs and current annual growth of Salix spp. in late summer. Graminoid wetlands dominated by Carex atherodes, Carex aquatilis, Carex utriculata, Scolochloa festucacea, or Calamagrostis stricta produced 1975-4575 kg ha(-1) of fair to good quality forage, whereas treed stands produced < 250 kg ha(-1) of forb-dominated forage (>85% content), which was below a published 25% foraging efficiency threshold of 263 kg ha(-1) for bison. Upland forests that dominate the region produced < or = 1 animal unit day (AUD) of forage per hectare in summer. Most forest understory plants were of poor forage value, suggesting the potential sustainable stocking rate of such areas was actually < or = 0.3 AUD ha(-1), with even lower rates during winter due to snow cover. Herbaceous wetlands contained approximately 78 AUD ha(-1) of forage, but were considered largely unavailable in summer because of flooding and soft organic soils that make access difficult. Conversion of prime foraging habitat to agricultural land, forest expansion due to fire control, and a warmer and wetter climatic regime after the mid-1900s likely contributed to a regional reduction in carrying capacity. It is hypothesized that substantial recovery of the wood bison population toward historical levels will be constrained in northern Alberta by the availability of summer forage, and the limited extent of graminoid wetlands that provide winter foraging habitat. PMID:18191321

Strong, Wayne L; Gates, C Cormack

2009-01-01

305

Field energetics and foraging mode of Kalahari lacertid lizards  

SciTech Connect

The authors examined the energetic costs associated with foraging mode in the widely foraging lizard Eremias lugubris (mean mass 3.83 g) and the sit-and-wait lizard Eremias lineoocellata (3.27 g). These lizards are broadly sympatric in the Kalahari desert. The widely foraging species had significantly higher field metabolic rates (800 vs. 544 J/d, as measured with doubly labeled water), feeding rates (metabolizable energy of 1165 vs. 739 J/d), production rates (365 vs. 195 J/d) and water influx rates (0.285 vs. 0.156 mL/d). Measurements were made before the reproductive season began; there were no significant differences in these measures between sexes within either species. Resting metabolic rates (measured as O/sub 2/ consumed) were similar at 37/sup 0/C (0.240 vs. 0.252 mL g/sup -1/ H/sup -1/) and 26/sup 0/ (0.094 vs. 0.103 mL g/sup -1/ h/sup -1/), the field active and nocturnal burrow temperatures respectively, of both species. Field metabolic rates, on a 24-h basis, were 3.1 x resting in E. lugubris and 2.2 x resting in E. lineoocellata. Energy expenditures during the activity period were 12.0 x resting in the wide forager and 2.8 x resting in the sit-and-wait predator. Foraging efficiency (metabolizable energy gained while foraging/total energy spent while foraging) was higher in the wide forager (2.0 than in the sit-and-wait predator. The wide forager grew nearly twice as fast as did the sit-and-wait predator during this study. On an annual basis, variation in food availability or differences in predation rate may alter the relative fitness of these foraging modes.

Nagy, K.A.; Huey, R.B.; Bennett, A.F.

1984-04-01

306

Diet Composition, Forage Selection, and Potential for Forage Competition Among Elk, Deer, and Livestock on Aspen–Sagebrush Summer Range  

Microsoft Academic Search

We evaluated elk (Cervus elaphus), mule deer (Odocoileus hemionus), cattle (Bos taurus), and domestic sheep (Ovis aries) diet composition, diet overlap, and forage selection on aspen (Populus tremuloides Michaux)-sagebrush (Artemisia spp. L.) summer range in northeastern Nevada to understand potential for forage competition to provide better information for managing these communities. Diets were determined through microhistological fecal analysis from 1998

Jeffrey L. Beck; James M. Peek

2005-01-01

307

Foraging Patch Selection and Departure by Non-Omniscient Foragers: A Field Example in White-Fronted Geese  

Microsoft Academic Search

Animals often face great uncertainty as to the quality of foraging pat- ches. There have been a number of theoretical studies investigating how non-omniscient predators, i.e. predators that are unable to assess for- aging patch quality prior to patch exploitation, should forage in a het- erogeneous environment, but empirical studies, especially in the field, are scarce. This paper describes the

Tatsuya Amano; Katsumi Ushiyama; Go Fujita; Hiroyoshi Higuchi

2006-01-01

308

NOCTURNAL FORAGING BEHAVIOR OF WINTERING SURF SCOTERS AND WHITE-WINGED SCOTERS  

Microsoft Academic Search

We studied the nocturnal foraging behavior of Surf Scoters (Melanitta perspi- cillata) and White-winged Scoters (Melanitta fusca) during winter in coastal British Colum- bia, Canada. Using radio telemetry, we collected nocturnal and diurnal data documenting the frequency of foraging dives and the location of scoters in relation to their intertidal foraging grounds. We found that dive foraging rarely occurred during

Tyler L. Lewis; Daniel Esler; W. Sean Boyd

2005-01-01

309

FOOD AND PREDATION RISK AS FACTORS RELATED TO FORAGING LOCATIONS OF NORTHERN FLICKERS  

Microsoft Academic Search

Foraging site selection by birds may be related to foraging efficiency, food availability and abundance, and predation risk. We identified selectively used foraging habitat within home ranges of 29 adult radio-tagged Northern Flickers (Colaptes auratus) in British Columbia during the nestling period. We compared habitat characteristics of flicker foraging locations to randomly selected locations in their home range using discriminant

CANDACE L. ELCHUK; KAREN L. WIEBE

2002-01-01

310

Foraging behaviour of Nuthatches (Sitta europaea) in relation to the presence of mates and mixed flocks  

Microsoft Academic Search

Summary Nuthatches (Sitta europaea) usually forage in pairs outside the breeding season. I investigated whether foraging site selection in winter (tree species, height, substrate size) differed between sexes and whether this difference was related to the presence of mixed-species flocks. Foraging sites of pair members foraging together were highly correlated. In the rare cases when each used different tree species,

Erik Matthysen

1999-01-01

311

The Effect of Conversion of Cropland to Forage Legumes on Soil Quality in a Semiarid Agroecosystem  

Microsoft Academic Search

This study explores the ecological restoration effects of the conversion of cropland to forage legumes on soil characteristics in the semi-arid Loess Plateau of China. Four types of treatments: fallow (F); alfalfa (Medicago sativa) forage legume (A); sweetclover (Melilotus officinalis) forage legume followed by fallow (SF) and erect milkvetch (Astragalus adsurgens) forage legume (E) were used to substitute for spring

Zhao-Xia Zeng; Xiao-Li Liu; Yu Jia; Feng-Min Li

2008-01-01

312

Proposed Use of Adjusted Intake Based on Forage Particle Length for Calculation of Roughage Indexes1  

Microsoft Academic Search

Effects of forage intake and particle length on chewing time were investigated. Two ratios of forage to concentrate, 33:67 and 50:50, and three lengths of forage particles were compared in two 3 x 3 Latin squares repeated a second year. Distribution of forage particle length was determined with an oscillating screen particle separator. Weighted mean particle lengths, .31, .43, and

F. J. Santini; A. R. Hardie; N. A. Jorgensen; M. F. Finner

1983-01-01

313

Biomimicry of Social Foraging Bacteria for Distributed Optimization: Models, Principles, and Emergent Behaviors1  

Microsoft Academic Search

In this paper, we explain the social foraging behavior of E. coli and M. xanthus bacteria and develop simulation models based on the principles of foraging theory that view foraging as optimization. This provides us with novel models of their foraging behavior and with new methods for distributed nongradient optimization. Moreover, we show that the models of both species of

Y. LIU; K. M. PASSINO

2002-01-01

314

Biomimicry of Social Foraging Bacteria for Distributed Optimization: Models, Principles, and Emergent Behaviors  

Microsoft Academic Search

In this paper, we explain the social foraging behavior of E. coli and M. xanthus bacteria and develop simulation models based on the principles of foraging theory that view foraging as optimization. This provides us with novel models of their foraging behavior and with new methods for distributed nongradient optimization. Moreover, we show that the models of both species of

Y. Liu; K. M. Passino

2002-01-01

315

Lambs fed protein or energy imbalanced diets forage in locations and on foods that rectify imbalances  

Microsoft Academic Search

Ruminants eat a variety of foods from different locations in the environment. While water, cover, social interactions, and predators are all likely to influence choice of foraging location, differences in macronutrient content among forages may also cause ruminants to forage in different locations even during a meal. We hypothesized that lambs forage at locations containing foods that complement their basal

Lindsey L Scott; Frederick D Provenza

2000-01-01

316

Group size, foraging, and antipredator ploys: An analysis of bighorn sheep decisions  

Microsoft Academic Search

1.Several aspects of the foraging behavior of California bighorn sheep (Ovis canadensis californiana) were studied in homogeneous habitats in the interior of British Columbia, Canada. The manner in which an individual sheep foraged was based upon the size of group within which it was found.2.In small groups (five or less individuals) sheep foraging efficiency was poor and interruptions of foraging

Joel Berger

1978-01-01

317

The effect of reproductive condition on the foraging behavior of female hoary bats, Lasiurus cinereus  

Microsoft Academic Search

Female mammals experience larg changes in time and energy budgets associated with reproduction and these may influence the foraging strategies of individuals. I studied the changes in foraging behavior associated with reproduction in female hoary bats, Lasiurus cinereus. As lactation progressed, individuals departed to forage earlier in the evening and spent more time foraging per night and less time roosting

R. M. R. Barclay

1989-01-01

318

Foraging methods can affect patch choice: an experimental study in Mallard ( Anas platyrhynchos)  

Microsoft Academic Search

Animals can adapt to changes in feeding conditions by switching between foraging methods. Dabbling ducks use different foraging methods, including dabbling in deep water with the head and neck submerged, and grubbing in the mud (or shallow water) where the eyes are above the surface, so the bird can visually monitor its environment while foraging. Deep foraging is considered to

Matthieu Guillemain; Hervé Fritz; Sandra Blais

2000-01-01

319

Foraging differences between cross-fostered honeybee workers ( Apis mellifera ) of European and Africanized races  

Microsoft Academic Search

Foraging differences between cross-fostered honeybee workers of European and Africanized races in South America are described. Africanized workers began foraging at earlier ages than European workers in colonies of their own races, but cross-fostered workers began foraging at the same age as workers in the colonies in which they were placed. Some differences in the mean time spent foraging per

Mark L. Winston; Susan J. Katz

1982-01-01

320

Floral odor learning within the hive affects honeybees' foraging decisions  

NASA Astrophysics Data System (ADS)

Honeybees learn odor cues quickly and efficiently when visiting rewarding flowers. Memorization of these cues facilitates the localization and recognition of food sources during foraging flights. Bees can also use information gained inside the hive during social interactions with successful foragers. An important information cue that can be learned during these interactions is food odor. However, little is known about how floral odors learned in the hive affect later decisions of foragers in the field. We studied the effect of food scent on foraging preferences when this learning is acquired directly inside the hive. By using in-hive feeders that were removed 24 h before the test, we showed that foragers use the odor information acquired during a 3-day stimulation period with a scented solution during a food-choice situation outside the nest. This bias in food preference is maintained even 24 h after the replacement of all the hive combs. Thus, without being previously collected outside by foragers, food odors learned within the hive can be used during short-range foraging flights. Moreover, correct landings at a dual-choice device after replacing the storing combs suggests that long-term memories formed within the colony can be retrieved while bees search for food in the field.

Arenas, Andrés; Fernández, Vanesa M.; Farina, Walter M.

2007-03-01

321

Personality, Foraging and Fitness Consequences in a Long Lived Seabird  

PubMed Central

While personality differences in animals are defined as consistent behavioural variation between individuals, the widely studied field of foraging specialisation in marine vertebrates has rarely been addressed within this framework. However there is much overlap between the two fields, both aiming to measure the causes and consequences of consistent individual behaviour. Here for the first time we use both a classic measure of personality, the response to a novel object, and an estimate of foraging strategy, derived from GPS data, to examine individual personality differences in black browed albatross and their consequences for fitness. First, we examine the repeatability of personality scores and link these to variation in foraging habitat. Bolder individuals forage nearer the colony, in shallower regions, whereas shyer birds travel further from the colony, and fed in deeper oceanic waters. Interestingly, neither personality score predicted a bird’s overlap with fisheries. Second, we show that both personality scores are correlated with fitness consequences, dependent on sex and year quality. Our data suggest that shyer males and bolder females have higher fitness, but the strength of this relationship depends on year quality. Females who forage further from the colony have higher breeding success in poor quality years, whereas males foraging close to the colony always have higher fitness. Together these results highlight the potential importance of personality variation in seabirds and that the fitness consequences of boldness and foraging strategy may be highly sex dependent. PMID:24504180

Patrick, Samantha C.; Weimerskirch, Henri

2014-01-01

322

Individual Foraging Strategies Reveal Niche Overlap between Endangered Galapagos Pinnipeds  

PubMed Central

Most competition studies between species are conducted from a population-level approach. Few studies have examined inter-specific competition in conjunction with intra-specific competition, with an individual-based approach. To our knowledge, none has been conducted on marine top predators. Sympatric Galapagos fur seals (Arctocephalus galapagoensis) and sea lions (Zalophus wollebaeki) share similar geographic habitats and potentially compete. We studied their foraging niche overlap at Cabo Douglas, Fernandina Island from simultaneously collected dive and movement data to examine spatial and temporal inter- and intra-specific competition. Sea lions exhibited 3 foraging strategies (shallow, intermediate and deep) indicating intra-specific competition. Fur seals exhibited one foraging strategy, diving predominantly at night, between 0–80 m depth and mostly at 19–22 h. Most sea lion dives also occurred at night (63%), between 0–40 m, within fur seals' diving depth range. 34% of sea lions night dives occurred at 19–22 h, when fur seals dived the most, but most of them occurred at dawn and dusk, when fur seals exhibited the least amount of dives. Fur seals and sea lions foraging behavior overlapped at 19 and 21 h between 0–30 m depths. Sea lions from the deep diving strategy exhibited the greatest foraging overlap with fur seals, in time (19 h), depth during overlapping time (21–24 m), and foraging range (37.7%). Fur seals foraging range was larger. Cabo Douglas northwest coastal area, region of highest diving density, is a foraging “hot spot” for both species. Fur seals and sea lions foraging niche overlap occurred, but segregation also occurred; fur seals primarily dived at night, while sea lions exhibited night and day diving. Both species exploited depths and areas exclusive to their species. Niche breadth generally increases with environmental uncertainty and decreased productivity. Potential competition between these species could be greater during warmer periods when prey availability is reduced. PMID:23967096

Villegas-Amtmann, Stella; Jeglinski, Jana W. E.; Costa, Daniel P.; Robinson, Patrick W.; Trillmich, Fritz

2013-01-01

323

The Organization of Foraging in the Fire Ant, Solenopsis invicta  

PubMed Central

Although natural selection in ants acts most strongly at the colony, or superorganismal level, foraging patterns have rarely been studied at that level, focusing instead on the behavior of individual foragers or groups of foragers. The experiments and observations in this paper reveal in broad strokes how colonies of the fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), allocate their available labor to foraging, how they disperse that force within their territory, and how this force changes with colony size, season and worker age. Territory area is positively related to colony size and the number of foragers, more so during the spring than fall. Changes of colony size and territory area are driven by seasonal variation of sexual and worker production, which in turn drive seasonal variation of worker age-distribution. During spring sexual production, colonies shrink because worker production falls below replacement. This loss is proportional to colony size, causing forager density in the spring to be negatively related to colony and territory size. In the fall, colonies emphasize worker production, bringing colony size back up. However, because smaller colonies curtailed spring worker production less than larger ones, their fall forager populations are proportionally greater, causing them to gain territory at the expense of large colonies. Much variation of territory area remains unexplained and can probably be attributed to pressure from neighboring colonies. Boundaries between territories are characterized by “no ants' zones” mostly devoid of fire ants. The forager population can be divided into a younger group of recruitable workers that wait for scouts to activate them to help retrieve large food finds. About one-third of the recruits wait near openings in the foraging tunnels that underlie the entire territory, while two-thirds wait in the nest. Recruitment to food is initially very rapid and local from the foraging tunnels, while sustained recruitment gradually involves the recruits waiting in the nest. As recruits age, they become scouts searching for food on the surface, and die about two weeks later. Foraging tunnels decrease in cross-sectional area with distance from the nest, in keeping with the gradual bleeding off of workers to the surface with distance. Foragers lack route-faithfulness, and having been marked and released at one point within the territory, they can be recaptured at any other point a day later. The size of the territory actually occupied may be limited during dry weather, resulting in very large no-ants' zones. PMID:21529150

Tschinkel, Walter R.

2011-01-01

324

Space use by foragers consuming renewable resources  

NASA Astrophysics Data System (ADS)

We study a simple model of a forager as a walk that modifies a relaxing substrate. Within it simplicity, this provides an insight on a number of relevant and non-intuitive facts. Even without memory of the good places to feed and no explicit cost of moving, we observe the emergence of a finite home range. We characterize the walks and the use of resources in several statistical ways, involving the behavior of the average used fraction of the system, the length of the cycles followed by the walkers, and the frequency of visits to plants. Preliminary results on population effects are explored by means of a system of two non directly interacting animals. Properties of the overlap of home ranges show the existence of a set of parameters that provides the best utilization of the shared resource.

Abramson, Guillermo; Kuperman, Marcelo N.; Morales, Juan M.; Miller, Joel C.

2014-05-01

325

Perceptions of livestock producers, forage producers, wildlife managers, and forage-based service providers concerning extension and technology-transfer activities in south Texas and northeast Mexico  

E-print Network

for increased effectiveness and collaboration among forage-based service providers. Data were collected from two samples in Spring and Summer 2001 using questionnaires. A sample of 92 livestock producers, forage producers, and wildlife managers was selected...

Folsom, Wendy Ann

2001-01-01

326

Managing forage and grazing lands for multiple ecosystem services  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage and grazing land systems are increasingly expected to provide services beyond food, feed, and fiber. The concept of multifunctionality in grassland agriculture recognizes ecosystem services beyond these traditional functions to include emerging services such as carbon sequestration, greenhous...

327

Quantifying rhizosphere respiration for two cool-season perennial forages  

Technology Transfer Automated Retrieval System (TEKTRAN)

Understanding the regulation of ecosystem carbon dioxide flux from forage production systems requires knowledge of component fluxes, including photosynthetic uptake and respiratory loss. Experimental separation of soil respiration into its heterotrophic (free-living soil organisms) and rhizosphere c...

328

Red Knots Forage for Horseshoe Crab Eggs at Delaware Bay  

USGS Multimedia Gallery

Red knots forage for horseshoe crab eggs and other invertebrates on the beaches of Delaware Bay. The bird in the center has an orange leg flag indicating it was captured and flagged in the past in Argentina....

329

Endophytic Fungi in Meadow Fescue and Other Forage Grasses  

E-print Network

Endophytic Fungi in Meadow Fescue and Other Forage Grasses Anja Bylin Faculty of Natural Resources uncinata (photo 3 and 4 from left) (photo: A. Bylin photo 1-3, S. Card photo 4 ) #12;Endophytic Fungi

330

Optimizing light availability for forages in silvopastoral systems: Modeled results  

Technology Transfer Automated Retrieval System (TEKTRAN)

Silvopastoral management optimizes the biophysical interactions between pasture species, trees, and grazing animals to increase the production efficiency and sustainability of the entire system. Synchronizing light availability for forage production with grazing animal production requirements requi...

331

Specialist Osmia bees forage indiscriminately among hybridizing Balsamorhiza floral hosts  

Technology Transfer Automated Retrieval System (TEKTRAN)

Even generalist pollinators are typically taxonomic specialists during individual foraging bouts. Such floral constancy restricts pollen flow, and thereby gene flow, between otherwise inter-fertile flowering species, thus serving as an ethological mating barrier. Among incipient species, however, ...

332

Pasture, Rangeland and Forage Risk Management Insurance Pilot Program Continues  

E-print Network

A new insurance program is available from USDA to protect producers from the loss of forage produced for grazing or harvested for hay. Insurance polices may be purchased through local crop insurance agents until November 30, 2007. This publication...

Pena, Jose G.; Bevers, Stan; Thompson, Bill

2007-10-29

333

Specialist Osmia Bees Forage Indiscriminately Among Hybridizing Balsamorhiza Floral Hosts  

Technology Transfer Automated Retrieval System (TEKTRAN)

Even generalist pollinators are typically taxonomic specialists during individual foraging bouts. Such floral constancy restricts pollen flow, and thereby gene flow, between otherwise inter-fertile flowering species, thus serving as an ethological mating barrier. Among incipient species, however, ...

334

DYNAPHORE, INC., FORAGER SPONGE TECHNOLOGY - INNOVATIVE TECHNOLOGY EVALUATION REPORT  

EPA Science Inventory

The Forager Sponge is a volume reduction technology in which heavy metal contaminants from an aqueous medium are selectively concentrated into a smaller volume for facilitated disposal. he technology treats contaminated groundwater, surface voters and porous waters by absorbing d...

335

Socially learned foraging behaviour in wild black bears, Ursus americanus  

Microsoft Academic Search

To date, research on social learning has been limited mainly to only a few taxa in captive or seminatural settings. We undertook a quantitative study of social learning in free-ranging black bears at Sequoia and Yosemite National Parks, U.S.A. from 1995 to 2006. We tested the hypothesis that food-conditioned forag- ing behaviour (foraging on human food in developed areas) by

Rachel Mazur; Victoria Seher

2008-01-01

336

Prescribed Fire Effects on Wintering, Bark-Foraging Birds  

Microsoft Academic Search

We examined effects of prescribed fire on 3 wintering, bark-foraging birds, hairy woodpeckers (Picoides villosus), pygmy nuthatches (Sitta pygmaea), and white-breasted nuthatches (S. carolinensis), in ponderosa pine (Pinus ponderosa) forests of northern Arizona, USA. During winters of 2004-2006, we compared bird density, foraging behavior, and bark beetle activity among burned treatment and unburned control units. Hairy woodpecker density was 5

THERESA L. POPE; WILLIAM M. BLOCK; PAUL BEIER

337

Oxidative phenols in forage crops containing polyphenol oxidase enzymes.  

PubMed

Polyphenol oxidases (PPOs) are copper-containing enzymes that catalyze oxidation of endogenous monophenols to ortho-dihydroxyaryl compounds and of ortho-dihydroxyaryl compounds to ortho-quinones. Subsequent nucleophilic addition reactions of phenols, amino acids, and proteins with the electrophilic ortho-quinones form brown-, black-, or red-colored secondary products associated with the undesired discolouration of fruit and vegetables. Several important forage plants also exhibit significant PPO activity, and a link with improved efficiency of ruminant production has been established. In ruminant animals, extensive degradation of forage proteins, following consumption, can result in high rates of excretion of nitrogen, which contributes to point-source and diffuse pollution. Reaction of quinones with forage proteins leads to the formation of protein-phenol complexes that are resistant to proteolytic activity during ensilage and during rumen fermentation. Thus, PPO in red clover (Trifolium pratense) has been shown to improve protein utilization by ruminants. While PPO activity has been demonstrated in a number of forage crops, little work has been carried out to identify substrates of PPO, knowledge of which would be beneficial for characterizing this trait in these forages. In general, a wide range of 1,2-dihydroxyarenes can serve as PPO substrates because these are readily oxidized because of the ortho positioning of the hydroxy groups. Naturally occurring phenols isolated from forage crops with PPO activity are reviewed. A large number of phenols, which may be directly or indirectly oxidized as a consequence of PPO activity, have been identified in several forage grass, legume, cereal, and brassica species; these include hydroxybenzoic acids, hydroxycinnamates, and flavonoids. In conclusion, a number of compounds are known or postulated to enable PPO activity in important PPO-expressing forage crops. Targeting the matching of these compounds with PPO activity would be a useful plant breeding approach to improve the utilization of feed nitrogen by ruminant livestock and help reduce the environmental impact of livestock agriculture in temperate countries. PMID:20078064

Parveen, Ifat; Threadgill, Michael D; Moorby, Jon M; Winters, Ana

2010-02-10

338

Foragers of the harvester ant, Pogonomyrmex owyheei : a disposable caste?  

Microsoft Academic Search

1.Exterior workers of the harvester ant, Pogonomyrmex owyheei, were subdivided into forager, defender and refuse worker behavior roles (Fig. 2). Exterior workers comprised approximately 16% of the total colony population with interior workers comprising the remainder.2.An average of less than 10% of the total worker population foraged (Table 1). Studies of role changes comfirmed a general one-way progression from interior

Sanford D. Porter; Clive D. Jorgensen

1981-01-01

339

Vision and Foraging in Cormorants: More like Herons than Hawks?  

Microsoft Academic Search

BackgroundGreat cormorants (Phalacrocorax carbo L.) show the highest known foraging yield for a marine predator and they are often perceived to be in conflict with human economic interests. They are generally regarded as visually-guided, pursuit-dive foragers, so it would be expected that cormorants have excellent vision much like aerial predators, such as hawks which detect and pursue prey from a

Craig R. White; Norman Day; Patrick J. Butler; Graham R. Martin; Peter Bennett

2007-01-01

340

The forager oral tradition and the evolution of prolonged juvenility.  

PubMed

The foraging niche is characterized by the exploitation of nutrient-rich resources using complex extraction techniques that take a long time to acquire. This costly period of development is supported by intensive parental investment. Although human life history theory tends to characterize this investment in terms of food and care, ethnographic research on foraging skill transmission suggests that the flow of resources from old-to-young also includes knowledge. Given the adaptive value of information, parents may have been under selection pressure to invest knowledge - e.g., warnings, advice - in children: proactive provisioning of reliable information would have increased offspring survival rates and, hence, parental fitness. One way that foragers acquire subsistence knowledge is through symbolic communication, including narrative. Tellingly, oral traditions are characterized by an old-to-young transmission pattern, which suggests that, in forager groups, storytelling might be an important means by which adults transfer knowledge to juveniles. In particular, by providing juveniles with vicarious experience, storytelling may expand episodic memory, which is believed to be integral to the generation of possible future scenarios (i.e., planning). In support of this hypothesis, this essay reviews evidence that: mastery of foraging knowledge and skill sets takes a long time to acquire; foraging knowledge is transmitted from parent to child; the human mind contains adaptations specific to social learning; full assembly of learning mechanisms is not complete in early childhood; and forager oral traditions contain a wide range of information integral to occupation of the foraging niche. It concludes with suggestions for tests of the proposed hypothesis. PMID:21897825

Scalise Sugiyama, Michelle

2011-01-01

341

The Forager Oral Tradition and the Evolution of Prolonged Juvenility  

PubMed Central

The foraging niche is characterized by the exploitation of nutrient-rich resources using complex extraction techniques that take a long time to acquire. This costly period of development is supported by intensive parental investment. Although human life history theory tends to characterize this investment in terms of food and care, ethnographic research on foraging skill transmission suggests that the flow of resources from old-to-young also includes knowledge. Given the adaptive value of information, parents may have been under selection pressure to invest knowledge – e.g., warnings, advice – in children: proactive provisioning of reliable information would have increased offspring survival rates and, hence, parental fitness. One way that foragers acquire subsistence knowledge is through symbolic communication, including narrative. Tellingly, oral traditions are characterized by an old-to-young transmission pattern, which suggests that, in forager groups, storytelling might be an important means by which adults transfer knowledge to juveniles. In particular, by providing juveniles with vicarious experience, storytelling may expand episodic memory, which is believed to be integral to the generation of possible future scenarios (i.e., planning). In support of this hypothesis, this essay reviews evidence that: mastery of foraging knowledge and skill sets takes a long time to acquire; foraging knowledge is transmitted from parent to child; the human mind contains adaptations specific to social learning; full assembly of learning mechanisms is not complete in early childhood; and forager oral traditions contain a wide range of information integral to occupation of the foraging niche. It concludes with suggestions for tests of the proposed hypothesis. PMID:21897825

Scalise Sugiyama, Michelle

2011-01-01

342

Impacts of Batrachochytrium dendrobatidis Infection on Tadpole Foraging Performance  

Microsoft Academic Search

Pathogen-induced modifications in host behavior, including alterations in foraging behavior or foraging efficiency, can compromise\\u000a host fitness by reducing growth and development. Chytridiomycosis is an infectious disease of amphibians caused by the fungus\\u000a Batrachochytrium dendrobatidis (Bd), and it has played an important role in the worldwide decline of amphibians. In larval anurans, Bd infections commonly result in reduced developmental rates,

Matthew D. Venesky; Matthew J. Parris; Andrew Storfer

2009-01-01

343

Do naive juvenile seabirds forage differently from adults?  

PubMed Central

Foraging skills of young individuals are assumed to be inferior to those of adults. The reduced efficiency of naive individuals may be the primary cause of the high juvenile mortality and explain the deferment of maturity in long-lived species. However, the study of juvenile and immature foraging behaviour has been limited so far. We used satellite telemetry to compare the foraging movements of juveniles, immatures and breeding adult wandering albatrosses Diomedea exulans, a species where foraging success is positively influenced by the distance covered daily. We showed that juveniles are able to use favourable winds as soon as the first month of independence, but cover shorter distances daily and spend more time sitting on water than adults during the first two months after fledging. These reduced movement capacities do not seem to be the cause of higher juvenile mortality. Moreover, juveniles almost never restrict their movement to specific areas, as adults and immatures frequently do over shelf edges or oceanic zones, which suggest that the location of appropriate areas is learned through experience. Immatures and adults have equivalent movement capacities, but when they are central place foragers, i.e. when adults breed or immatures come to the colony to display and pair, immatures make shorter trips than adults. The long duration of immaturity in this species seems to be related to a long period of learning to integrate the foraging constraints associated with reproduction and central place foraging. Our results indicate that foraging behaviour of young albatrosses is partly innate and partly learned progressively over immaturity. The first months of learning appear critical in terms of survival, whereas the long period of immaturity is necessary for young birds to attain the skills necessary for efficient breeding without fitness costs. PMID:23926153

Riotte-Lambert, Louise; Weimerskirch, Henri

2013-01-01

344

Animation 1. Top view of data from a multibeam sonar observations of dolphin foraging. This animation is a composite of three observations overlapping in foraging  

E-print Network

1 Animation 1. Top view of data from a multibeam sonar observations of dolphin foraging of a complete foraging bout. Each frame is the composite of six successive sonar echoes, providing higher a multibeam sonar observation of a foraging dolphins. This animation is a composite of three observations

Benoit-Bird, Kelly J.

345

Central place foraging by beavers ( Castor canadensis ): a test of foraging predictions and the impact of selective feeding on the growth form of cottonwoods ( Populus fremontii )  

Microsoft Academic Search

Several predictions of central place foraging theory were tested. As predicted, beavers foraged more selectively at increasing distance from the central place. With increasing distance from the river's edge, beavers cut fewer branches and deleted small branches from their diet. Large branches were favored at all distances, which differs from patterns observed in previous studies of beaver foraging. This difference,

Mark A. McGinley; Thomas G. Whitham

1985-01-01

346

Chaos–order transition in foraging behavior of ants  

PubMed Central

The study of the foraging behavior of group animals (especially ants) is of practical ecological importance, but it also contributes to the development of widely applicable optimization problem-solving techniques. Biologists have discovered that single ants exhibit low-dimensional deterministic-chaotic activities. However, the influences of the nest, ants’ physical abilities, and ants’ knowledge (or experience) on foraging behavior have received relatively little attention in studies of the collective behavior of ants. This paper provides new insights into basic mechanisms of effective foraging for social insects or group animals that have a home. We propose that the whole foraging process of ants is controlled by three successive strategies: hunting, homing, and path building. A mathematical model is developed to study this complex scheme. We show that the transition from chaotic to periodic regimes observed in our model results from an optimization scheme for group animals with a home. According to our investigation, the behavior of such insects is not represented by random but rather deterministic walks (as generated by deterministic dynamical systems, e.g., by maps) in a random environment: the animals use their intelligence and experience to guide them. The more knowledge an ant has, the higher its foraging efficiency is. When young insects join the collective to forage with old and middle-aged ants, it benefits the whole colony in the long run. The resulting strategy can even be optimal. PMID:24912159

Li, Lixiang; Peng, Haipeng; Kurths, Jürgen; Yang, Yixian; Schellnhuber, Hans Joachim

2014-01-01

347

Waggle Dance Distances as Integrative Indicators of Seasonal Foraging Challenges  

PubMed Central

Even as demand for their services increases, honey bees (Apis mellifera) and other pollinating insects continue to decline in Europe and North America. Honey bees face many challenges, including an issue generally affecting wildlife: landscape changes have reduced flower-rich areas. One way to help is therefore to supplement with flowers, but when would this be most beneficial? We use the waggle dance, a unique behaviour in which a successful forager communicates to nestmates the location of visited flowers, to make a 2-year survey of food availability. We “eavesdropped” on 5097 dances to track seasonal changes in foraging, as indicated by the distance to which the bees as economic foragers will recruit, over a representative rural-urban landscape. In year 3, we determined nectar sugar concentration. We found that mean foraging distance/area significantly increase from springs (493 m, 0.8 km2) to summers (2156 m, 15.2 km2), even though nectar is not better quality, before decreasing in autumns (1275 m, 5.1 km2). As bees will not forage at long distances unnecessarily, this suggests summer is the most challenging season, with bees utilizing an area 22 and 6 times greater than spring or autumn. Our study demonstrates that dancing bees as indicators can provide information relevant to helping them, and, in particular, can show the months when additional forage would be most valuable. PMID:24695678

Couvillon, Margaret J.; Schürch, Roger; Ratnieks, Francis L. W.

2014-01-01

348

Foraging Ecology Predicts Learning Performance in Insectivorous Bats  

PubMed Central

Bats are unusual among mammals in showing great ecological diversity even among closely related species and are thus well suited for studies of adaptation to the ecological background. Here we investigate whether behavioral flexibility and simple- and complex-rule learning performance can be predicted by foraging ecology. We predict faster learning and higher flexibility in animals hunting in more complex, variable environments than in animals hunting in more simple, stable environments. To test this hypothesis, we studied three closely related insectivorous European bat species of the genus Myotis that belong to three different functional groups based on foraging habitats: M. capaccinii, an open water forager, M. myotis, a passive listening gleaner, and M. emarginatus, a clutter specialist. We predicted that M. capaccinii would show the least flexibility and slowest learning reflecting its relatively unstructured foraging habitat and the stereotypy of its natural foraging behavior, while the other two species would show greater flexibility and more rapid learning reflecting the complexity of their natural foraging tasks. We used a purposefully unnatural and thus species-fair crawling maze to test simple- and complex-rule learning, flexibility and re-learning performance. We found that M. capaccinii learned a simple rule as fast as the other species, but was slower in complex rule learning and was less flexible in response to changes in reward location. We found no differences in re-learning ability among species. Our results corroborate the hypothesis that animals’ cognitive skills reflect the demands of their ecological niche. PMID:23755146

Clarin, Theresa M. A.; Ruczy?ski, Ireneusz; Page, Rachel A.

2013-01-01

349

Information Foraging in Nuclear Power Plant Control Rooms  

SciTech Connect

nformation foraging theory articulates the role of the human as an 'informavore' that seeks information and follows optimal foraging strategies (i.e., the 'information scent') to find meaningful information. This paper briefly reviews the findings from information foraging theory outside the nuclear domain and then discusses the types of information foraging strategies operators employ for normal and off-normal operations in the control room. For example, operators may employ a predatory 'wolf' strategy of hunting for information in the face of a plant upset. However, during routine operations, the operators may employ a trapping 'spider' strategy of waiting for relevant indicators to appear. This delineation corresponds to information pull and push strategies, respectively. No studies have been conducted to determine explicitly the characteristics of a control room interface that is optimized for both push and pull information foraging strategies, nor has there been empirical work to validate operator performance when transitioning between push and pull strategies. This paper explores examples of control room operators as wolves vs. spiders and con- cludes by proposing a set of research questions to investigate information foraging in control room settings.

R.L. Boring

2011-09-01

350

Attenuation and reacquisition of foraging behavior in a patchy environment.  

PubMed

The present experiment examined the attenuation and reacquisition of foraging behavior of pigeons on a restricted diet. Using the procedure of Roberts (1988), thirty-two feeders were arranged in four circular patches of eight feeders each. The feeders were baited so that each patch contained a different density of food. Pigeons learned to forage among the patches. During this initial acquisition phase, visits to the patches by the pigeons differed as a function of the food density of the patches. After this initial foraging training phase, each pigeon received one of two response elimination procedures. For half of the subjects, food was not present during the response elimination phase. For the remaining subjects, food was placed exclusively outside the patches during this phase. Foraging behavior decreased quickly and somewhat similarly for both conditions. During a final phase in which the retraining of the original foraging behavior occurred, the group given food outside the patches during response elimination provided evidence of superior foraging with respect to sensitivity to the different patch food densities. The results are discussed with regard to previously published response elimination effects. PMID:24896873

Mitchell, K G; Calton, J L; Threlkeld, R C; Schachtman, T R

1996-06-01

351

Sex-specific foraging behaviour in a monomorphic seabird.  

PubMed Central

Sexual differences in the foraging behaviour of parents have been observed in a number of sexually sizedimorphic birds, particularly seabirds, and the usual inference has been that these sex-specific differences are mediated primarily by differences in body size. To test this explanation, we compared the foraging behaviour of parents in a monomorphic seabird species, the northern gannet Morus bassanus. Using specially designed instruments and radio telemetry we found that individuals of both sexes were consistent in the directions and durations of their foraging trips. However, there were significant differences in the foraging behaviour of males and females. Female gannets were not only more selective than males in the areas where they foraged, but they also made longer, deeper dives and spent more time on the sea surface than males. As the sexes are morphologically similar in this species, then these differences are unlikely to have been mediated by body size. Our work highlights the need to investigate sexual differences in the foraging behaviour of seabirds and other species more closely, in order to test alternative theories that do not rely on differences in body size. PMID:12204129

Lewis, S; Benvenuti, S; Dall'Antonia, L; Griffiths, R; Money, L; Sherratt, T N; Wanless, S; Hamer, K C

2002-01-01

352

Foraging decisions, patch use, and seasonality in egrets (Aves: ciconiiformes)  

USGS Publications Warehouse

Feeding snowy (Egretta thula) and great (Casmerodius albus) egrets were observed during 2 breeding seasons in coastal New Jersey and 2 brief winter periods in northeast Florida (USA). A number of tests based on assumptions of foraging models, predictions from foraging theory, and earlier empirical tests concerning time allocation and movement in foraging patches was made. Few of the expectations based on foraging theory and/or assumptions were supported by the empirical evidence. Snowy egrets fed with greater intensity and efficiency during the breeding season (when young were being fed) than during winter. They also showed some tendency to leave patches when their capture rate declined, and they spent more time foraging in patches when other birds were present nearby. Great egrets showed few of these tendencies, although they did leave patches when their intercapture intervals increased. Satiation differences had some influence on feeding rates in snowy egrets, but only at the end of feeding bouts. Some individuals of both species revisited areas in patches that had recently been exploited, and success rates were usually higher after the 2nd visit. Apparently, for predators of active prey, short-term changes in resource availability ('resource depression') may be more important than resource depletion, a common assumption in most optimal foraging theory models.

Erwin, R.M.

1985-01-01

353

Trends in Abundance and Mean Size of Fish Captured in Gill Nets from Minnesota Lakes, 1983–1997  

Microsoft Academic Search

We investigated seasonal and 15-year trends in catch per unit effort (CPUE) and mean weight of black crappies Pomoxis nigromaculatus, ciscoes Coregonus artedi, northern pike Esox lucius, walleyes Sander vitreus (formerly Stizostedion vitreum), white suckers Catostomus commersoni, and yellow perch Perca flavescens captured in gill nets from 433 Minnesota lakes between 1983 and 1997. Seasonal trends were modeled using least-squares

Gerold C. Grant; Yaniv Schwartz; Sanford Weisberg; Dennis H. Schupp

2004-01-01

354

Fish Community Responses to the Introduction of Muskellunge in Minnesota Lakes  

Microsoft Academic Search

Abstract—We evaluated responses of seven ,fish species to muskellunge ,by comparing catch per unit effort (CPUE) before and after muskellunge ,were stocked in 41 Minnesota lakes composed of 12 lake classes. The species examined were: northern pike Esox lucius, walleye Sander vitreus, yellow perch Perca flavescens, bluegill Lepomis macrochirus, black crappie Pomoxis nigromaculatus, white sucker Catostomus commersoni, and tullibee Core-

Michael L. Knapp; Steven W. Mero; David J. Bohlander; David F. Staples; E. Hwy; Grand Rapids

355

Some Factors Influencing Seasonal Changes in Angler Catch in a Minnesota Lake  

Microsoft Academic Search

An investigation was undertaken in a small Minnesota lake to determine the relationship between angler success for northern pike (Esox lucius), bluegill (Lepomis macrochirus), and crappie (Pomoxis nigromaculatus) and food availability and food selectivity by these species. Fishing success was determined by creel census and food selectivity by stomach analysis of angler-caught fish. Food availability was determined by bottom sampling

Fred E. Lux; Lloyd L. Smith Jr

1960-01-01

356

Seasonal Variation in Catch Rate and Body Condition for Four Fish Species in a South Dakota Natural Lake  

Microsoft Academic Search

Seasonal variation in catch rate (catch per unit effort, CPUE) and body condition (relative weight, Wr) for northern pike Esox lucius, black crappie Pomoxis nigromaculatus, yellow perch Perca flavescens, and walleye Stizostedion vitreum sampled with trap (modified fyke) nets was evaluated in Lake Madison, a natural lake in eastern South Dakota, from March through October, 1990. Seasonal variation in CPUE

Christopher S. Guy; David W. Willis

1991-01-01

357

Relation between trophic position and mercury accumulation among fishes from the Tongue River Reservoir, Montana  

Microsoft Academic Search

Concentrations of total mercury were determined in muscle tissue from northern pike (Esox lucius), sauger (Stizostedion canadense), walleye (S. vitreum), black crappie (Pomoxis nigromaculatus), and white crappie (P. annularis) collected from the Tongue River Reservoir, Montana, prior to extensive surface coal-mine development in the region. Mercury concentrations in fish flesh increased with fish size and age; larger individuals of all

Glenn R. Phillips; Thomas E. Lenhart; Richard W. Gregory

1980-01-01

358

The Length-Weight Relationship, Factors for Conversions between Standard and Total Lengths, and Coefficients of Condition for Seven Michigan Fishes  

Microsoft Academic Search

The factors for conversions between standard and total lengths are presented for the following Michigan fishes: bluegill (Lepomis m. macrochirus), yellow perch (Perca flavescens), pumpkinseed (Lepomis gibbosus), smallmouth black bass (Micropterus d. dolomicu), largemouth black bass (Huro salmoides), rock bass (Ambloplites r. rupestris), and the northern pike (Esox lucius). The ratio of standard to total length was found to increase

William C. Beckman

1948-01-01

359

Evaluation of the toxicity and efficacy of hydrogen peroxide treatments on eggs of warm- and coolwater fishes  

Microsoft Academic Search

The use of hydrogen peroxide in aquaculture is growing and there is a need to develop fundamental guidelines to effectively treat diseased fish. The safety (toxicity) of hydrogen peroxide treatments was determined on eggs of representative warm- and coolwater fish species. Eggs of northern pike (Esox lucius), walleye (Stizostedion vitreum), yellow perch (Perca flavescens), white sucker (Catostomus commersoni), lake sturgeon

Jeff J Rach; Mark P Gaikowski; George E Howe; Theresa M Schreier

1998-01-01

360

A BroadScale Approach to Management of Ontario's Recreational Fisheries  

Microsoft Academic Search

Sustainable exploitation of Ontario's aquatic resources calls for a new management approach. This vast resource includes more than 250,000 lakes and offers angling opportunities for many popular species (e.g., walleye Sander vitreus (formerly Stizostedion vitreum), lake trout Salvelinus namaycush, brook trout S. fontinalis, northern pike Esox lucius, smallmouth bass Micropterus dolomieu, largemouth bass M. salmoides, and muskellunge E. masquinongy). In

Nigel P. Lester; Terry R. Marshall; Kim Armstrong; Warren I. Dunlop; Bev Ritchie

2003-01-01

361

Interactions between Walleyes and Four Fish Species with Implications for Walleye Stocking  

Microsoft Academic Search

We used a number of different data sets and four criteria to evaluate evidence of competition and predation between walleye Sander vitreus and northern pike Esox lucius, muskellunge E. masquinongy, smallmouth bass Micropterus dolomieu, and largemouth bass M. salmoides in northern Wisconsin lakes. The four criteria were as follows: (1) indices of population abundance were inversely related, (2) two species

Andrew H. Fayram; Michael J. Hansen; Timothy J. Ehlinger

2005-01-01

362

Biological Methylation of Mercury in Aquatic Organisms  

Microsoft Academic Search

FRESHWATER fish, especially pike (Esox lucius), from Sweden sometimes contain abnormally large amounts of mercury1. It was initially concluded to be either inorganic mercury or phenyl mercury, which are known to be released as industrial wastes, but later it was shown that the mercury was present almost entirely as methyl mercury (CH3Hg+)2. A possible explanation is that living organisms have

S. Jensen; A. JERNELÖV

1969-01-01

363

INTERNATIONAL PROSPECTUS 20152016 STUDY AT SLU  

E-print Network

, such as global warming, the food crisis, and our dependence on non- renewable energy. Students are encouragedEsox lucius (x - x1)² + (y - y CONTENT 2 WELCOME TO SLU AND SWEDEN! 4 SLU in brief 6 Why study in Sweden? 8

364

Qualitative indices of edible and inedible products obtained from fish in the lower Yenisei River basin  

Microsoft Academic Search

The results of biochemical investigations of samples of products obtained from burbot (Lota lota L.), perch (Perca fluviatilis L.), and pike (Esox lucius L.) inhabiting the lower reaches of the Yenisei River basin are given. Biologically active substances—macro- and microelements,\\u000a fatty acids, amino acids, and vitamins—are analyzed.

A. A. Gnedov; A. A. Kaizer

2010-01-01

365

Alexander Creek in the Susitna Basin  

USGS Multimedia Gallery

Researchers with the Alaska Fish and Game travel along Alexander Creek in the Susitna Basin of south-central Alaska. The team is on their way to a back country base-camp for a study examining the preferred diet of invasive northern pike (Esox lucius).  ...

366

Mercury and selenium concentrations in muscle tissue of different species of predatory freshwater fish and correlation between these elements  

Microsoft Academic Search

Concentrations of total mercury and selenium were determined in 49 and 42 muscle tissue samples, respectively, of six species of predatory freshwater fish, dace (Leuciscus leuciscus), pike perch (Sander lucioperca), pike (Esox lucius), European catfish (Silurus glanis), rainbow trout (Oncorhynchus mykiss) and asp (Aspius aspius). Muscle selenium concentration did not correlate with the corresponding total mercury concentration (R

Imrich Strapá?; Jozef Sokol; Daniel Žatko; Mária Baranová

2012-01-01

367

Assessing Organic Contaminants in Fish: Comparison of a Nonlethal  

E-print Network

) in flathead catfish (Pylodictis olivaris), relative to those found in muscle fillets of the same fish. We also) attached directly to wild flathead catfish for assessing location-specific exposure of the fish lake whitefish (Coregonus clupeaformis) and northern pike (Esox lucius) for the analysis of mercury (Hg

Cope, W. Gregory

368

Effects of exposure to seismic airgun use on hearing of three fish species  

Microsoft Academic Search

Seismic airguns produce considerable amounts of acoustic energy that have the potential to affect marine life. This study investigates the effects of exposure to a 730 in.3 airgun array on hearing of three fish species in the Mackenzie River Delta, the northern pike (Esox lucius), broad whitefish (Coregonus nasus), and lake chub (Couesius plumbeus). Fish were placed in cages in

Arthur N. Popper; Michael E. Smith; Peter A. Cott; Bruce W. Hanna; Alexander O. MacGillivray; Melanie E. Austin; David A. Mann

2005-01-01

369

Comparison of mercury and methylmercury in northern pike and Arctic grayling from western Alaska rivers  

Microsoft Academic Search

In western Alaska, mercury (Hg) could be a potential health risk to people whose diet is primarily fish-based. In 2000, total Hg (THg) and methylmercury (MeHg) were examined in northern pike (Esox lucius) and Arctic grayling (Thymallus arcticus) from two watersheds in western Alaska, the Yukon and Kuskokwim rivers. Whitefish (Coregonus sp.) were also examined from the Kuskokwim River. Pike

Stephen C. Jewett; Xiaoming Zhang; A. Sathy Naidu; John J. Kelley; Doug Dasher; Lawrence K. Duffy

2003-01-01

370

Largemouth Bass Predation on Stocked Tiger Muskellunge  

Microsoft Academic Search

To better understand why stocked esocids survive poorly, we estimated mortality rates of tiger muskellunge (F1 hybrid of female muskellunge Esox masquinongy x male northern pike E. lucius) that were placed into two Ohio reservoirs (mean fish total lengths, 171 and 179 mm; 62 fish per hectare). Because pond experiments showed that hybrids stocked at night experienced mortality rates as

Roy A. Stein; Robert F. Carline; Robert S. Hayward

1981-01-01

371

Nutritional Requirements and Feeding of Selected Coolwater Fishes: A Review  

Microsoft Academic Search

A review was made of published and unpublished studies on nutritional requirements, diets, and feeding of selected coolwater species of fishes: yellow perch (Perca flavescens), European perch (P. fluviatilis), walleye (Stizostedion vitreum), smallmouth bass (Micropterus dolomieui), northern pike (Esox lucius), muskellunge (E. masquinongy), and the northern pike x muskellunge hybrid. The published information on nutritional requirements was meager, including only

H. George Ketola

1978-01-01

372

Predation by Pellet-Reared Tiger Muskellunge on Minnows and Bluegills in Experimental Systems  

Microsoft Academic Search

Studies in Wisconsin lakes have shown that stocked tiger muskellunge (F1 hybrids of female muskellunge, Esox masquinongy x male northern pike, E. lucius) reared on live food survive better than those reared entirely on dry pellet food. We evaluated the ability of pellet-reared hybrids to convert to a minnow (Notropis spp. and Pimephales promelas) or bluegill (Lepomis macrochirus) diet in

Alan L. Gillen; Roy A. Stein; Robert F. Carline

1981-01-01

373

Application of Liquid Oxytetracycline in Formulated Feeds to Mark and Treat Tiger Muskellunge (Northern Pike X Muskellunge)  

Microsoft Academic Search

When added to pelleted diets, liquid oxytetracycline (500 mg\\/kg of fish per day) was effective in marking (after 12 d) and disease treatment (after 3 d) of tiger muskellunge (the hybrid of northern pike, Esox lucius, and muskellunge, E. masquinongy). Liquid oxytetracycline is more easily applied and costs less than traditional methods for these purposes.

David H. Wahl; Roy A. Stein

1987-01-01

374

Growth of Tiger Muskellunge Fed Different Amounts of Protein at Three Water Temperatures  

Microsoft Academic Search

Growth rates of tiger muskellunge (muskellunge Esox masquinongy ? x northern pike E. lucius ?) fed diets containing 35, 45, or 55% crude protein for 5 weeks at 17, 20, or 23°C were compared. Fish fed diets containing 45 or 55% protein grew faster at all temperatures than those fed 35% protein. Growth of tiger muskellunge fed a diet containing

Carol A. Lemm; Donald V. Rottiers

1986-01-01

375

Effects of exposure to predatory cues on territorial behaviour of male fathead minnows  

Microsoft Academic Search

We conducted a laboratory study to determine if male fathead minnows, Pimephales promelas, altered their territorial behaviour associated with reproduction in response to combinations of visual and chemical cues from northern pike, Esox lucius. We introduced the following stimuli to a territorial male: a brick (control), fathead minnow alarm pheromone, a pike fed brook stickleback, Culea inconstans, or a pike

Hilary M. Jones; Cynthia A. Paszkowski

1997-01-01

376

Genetic Divergence among Northern Pike from Spawning Locations in the Upper St. Lawrence River  

Microsoft Academic Search

To assess the ecological consequences associated with the degradation of riparian wetlands that historically provided spawning and rearing habitat for northern pike Esox lucius, annual spawning migrations and genetic structure were used to examine this species' dependence on four specific spawning areas in the Thousand Islands region of the Saint Lawrence River. Tagging and recapture over three consecutive spawning seasons

Aaron Bosworth; John M. Farrell

2006-01-01

377

Structures to Prevent the Spread of Nuisance Fish from Lake Davis, California  

Microsoft Academic Search

Methods to contain the spread of nuisance or otherwise undesirable fish species are relatively limited. I describe an unconventional method used to help restrict the movement of northern pike Esox lucius from a mountain reservoir into downstream waters. Reservoir managers designed, installed, and monitored steel structures (“graters”) that served to increase the likelihood that fish entrained in discharge from Lake

Douglas B. C. Rischbieter

2000-01-01

378

WINTER MOVEMENTS OF FOUR FISH SPECIES NEAR A THERMAL PLUME IN NORTHERN MINNESOTA (JOURNAL VERSION)  

EPA Science Inventory

During winter 1975, 17 yellow perch (Perca flavescens), 6 northern pike (Esox lucius), 3 walleyes (Stizostedion vitreum), and 2 largemouth bass (Micropterus salmoides) were equipped with radio frequency transmitters to compare their winter movements near the thermal plume of a po...

379

SPATIAL DISTRIBUTION AND TEMPERATURE SELECTION OF FISH NEAR THE THERMAL OUTFALL OF A POWER PLANT DURING FALL, WINTER, AND SPRING  

EPA Science Inventory

The movement patterns of 4 fish species: yellow perch (Perca flavescens), northern pike (Esox lucius), largemouth bass (Micropterus salmoides) and walleye (Stizostedion vitreum) were monitored by radio telemetry near the thermal discharge of a power plant (delta T 15C nominal). F...

380

Damselfly larvae learn to recognize predators from chemical cues in the predator's diet  

Microsoft Academic Search

Chemosensory recognition of predators by naive prey may be facilitated if the predator's diet chemically ‘labels’ the predator. In a laboratory experiment, behaviour patterns were quantified in individual damselfly larvae,Enallagmaspp., that had never been exposed to pike,Esox lucius, before and after exposing the damselflies to one of three chemical stimuli: water from a tank that held pike fed a diet

DOUGLAS P. CHIVERS; BRIAN D. WISENDEN; R. JAN F. SMITH

1996-01-01

381

Persistence of forage fish ‘hot spots’ and its association with foraging Steller sea lions (Eumetopias jubatus) in southeast Alaska  

NASA Astrophysics Data System (ADS)

Whereas primary and secondary productivity at oceanic 'hotspots' may be a function of upwelling and temperature fronts, the aggregation of higher-order vertebrates is a function of their ability to search for and locate these areas. Thus, understanding how predators aggregate at these productive foraging areas is germane to the study of oceanic hot spots. We examined the spatial distribution of forage fish in southeast Alaska for three years to better understand Steller sea lion ( Eumetopias jubatus) aggregations and foraging behavior. Energy densities (millions KJ/km 2) of forage fish were orders of magnitude greater during the winter months (November-February), due to the presence of schools of overwintering Pacific herring ( Clupea pallasi). Within the winter months, herring consistently aggregated at a few areas, and these areas persisted throughout the season and among years. Thus, our study area was characterized by seasonally variable, highly abundant but highly patchily distributed forage fish hot spots. More importantly, the persistence of these forage fish hot spots was an important characteristic in determining whether foraging sea lions utilized them. Over 40% of the variation in the distribution of sea lions on our surveys was explained by the persistence of forage fish hot spots. Using a simple spatial model, we demonstrate that when the density of these hot spots is low, effort necessary to locate these spots is minimized when those spots persist through time. In contrast, under similar prey densities but lower persistence, effort increases dramatically. Thus an important characteristic of pelagic hot spots is their persistence, allowing predators to predict their locations and concentrate search efforts accordingly.

Gende, Scott M.; Sigler, Michael F.

2006-02-01

382

Eye structure and amphibious foraging in albatrosses  

PubMed Central

Anterior eye structure and retinal visual fields were determined in grey-headed and black-browed albatrosses, Diomedea melanophris and D. chrysostoma (Procellariiformes, Diomedeidae), using keratometry and an ophthalmoscopic reflex technique. Results for the two species were very similar and indicate that the eyes are of an amphibious optical design suggesting that albatross vision is well suited to the visual pursuit of active prey both on and below the ocean surface. The corneas are relatively flat (radius ca. 14.5 mm) and hence of low absolute refractive power (ca. 23 dioptres). In air the binocular fields are relatively long (vertical extent ca. 70 degrees) and narrow (maximum width in the plane of the optic axes 26–32 degrees), a topography found in a range of bird species that employ visual guidance of bill position when foraging. The cyclopean fields measure approximately 270 degrees in the horizontal plane, but there is a 60 degrees blind sector above the head owing to the positioning of the eyes below the protruding supraorbital ridges. Upon immersion the monocular fields decrease in width such that the binocular fields are abolished. Anterior eye structure, and visual field topography in both air and water, show marked similarity with those of the Humboldt penguin.

Martin, G. R.

1998-01-01

383

Color and polarization vision in foraging Papilio.  

PubMed

This paper gives an overview of behavioral studies on the color and polarization vision of the Japanese yellow swallowtail butterfly, Papilio xuthus. We focus on indoor experiments on foraging individuals. Butterflies trained to visit a disk of certain color correctly select that color among various other colors and/or shades of gray. Correct selection persists under colored illumination, but is systematically shifted by background colors, indicating color constancy and simultaneous color contrast. While their eyes contain six classes of spectral receptors, their wavelength discrimination performance indicates that their color vision is tetrachromatic. P. xuthus innately prefers brighter targets, but can be trained to select dimmer ones under certain conditions. Butterflies trained to a dark red stimulus select an orange disk presented on a bright gray background over one on dark gray. The former probably appears darker to them, indicating brightness contrast. P. xuthus has a strong innate preference for vertically polarized light, but the selection of polarized light changes depending on the intensity of simultaneously presented unpolarized light. Discrimination of polarization also depends on background intensity. Similarities between brightness and polarization vision suggest that P. xuthus perceive polarization angle as brightness, such that vertical polarization appears brighter than horizontal polarization. PMID:24722674

Kinoshita, Michiyo; Arikawa, Kentaro

2014-06-01

384

Specialist Osmia bees forage indiscriminately among hybridizing Balsamorhiza floral hosts.  

PubMed

Pollinators, even floral generalists (=polyleges), typically specialize during individual foraging bouts, infrequently switching between floral hosts. Such transient floral constancy restricts pollen flow, and thereby gene flow, to conspecific flowers in mixed plant communities. Where incipient flowering species meet, however, weak cross-fertility and often similar floral traits can yield mixed reproductive outcomes among pollinator-dependent species. In these cases, floral constancy by polyleges sometimes serves as an ethological mating barrier. More often, their foraging infidelities instead facilitate host introgression and hybridization. Many other bee species are oligolectic (taxonomic specialists for pollen). Oligoleges could be more discriminating connoisseurs than polyleges when foraging among their limited set of related floral hosts. If true, greater foraging constancy might ensue, contributing to positive assortative mating and disruptive selection, thereby facilitating speciation among their interfertile floral hosts. To test this Connoisseur Hypothesis, nesting females of two species of oligolectic Osmia bees were presented with randomized mixed arrays of flowers of two sympatric species of their pollen host, Balsamorhiza, a genus known for hybridization. In a closely spaced grid, the females of both species preferred the larger flowered B. macrophylla, evidence for discrimination. However, both species' females showed no floral constancy whatsoever during their individual foraging bouts, switching randomly between species proportional to their floral preference. In a wider spaced array in which the bouquets reflected natural plant spacing, foraging oligolectic bees often transferred pollen surrogates (fluorescent powders) both between conspecific flowers (geitonogamy and xenogamy) and between the two Balsamorhiza species. The Connoisseur Hypothesis was therefore rejected. Foraging infidelity by these oligolectic Osmia bees will contribute to introgression and hybridization where interfertile species of Balsamorhiza meet and flower together. A literature review reveals that other plant genera whose species hybridize also attract numerous oligolectic bees, providing independent opportunities to test the generality of this conclusion. PMID:21468665

Cane, James H

2011-09-01

385

Insect prey foraging strategies in Callicebus oenanthe in northern Peru.  

PubMed

Titi monkeys (genus Callicebus) are small-bodied platyrrhines that supplement their predominantly frugivorous diet with variable amounts of leaves, seeds, and/or arthropod prey. Notable interspecific variation in the amount of insect prey in the diet has been observed in Callicebus, ranging from 0% to 20%. In this study, I investigate the degree and type of prey foraging in a little-known species, Callicebus oenanthe inhabiting a fragmented, secondary forest on the foothills of the Andes in northern Peru. I present data on prey type, prey search and capture techniques, substrate/vegetation use, foraging height, prey capture efficiency, and seasonal variation of insect prey foraging in one group of C. oenanthe observed from January to August 2005. Insect prey accounted for 22% of the diet, the highest amount reported for any Callicebus species to date, and insects from at least six different orders were included. C. oenanthe was mainly an investigative forager of hidden prey, manipulating easy-to-open substrates such as rolled up leaves, and hunted ant swarms and larger insects opportunistically. Insect foraging was predominant during the dry season (26%) and decreased during the wet season (13%). The study group foraged mostly in the understory (2-6 m) within vine-laden shrubs and trees, which may conform to an anti-predator strategy of crypticity. Overall the group had an 83% insect capture success rate. These data suggest that insect prey is an important part of the diet of C. oenanthe and may be especially notable during periods of resource scarcity. This study adds to the knowledge concerning insect prey foraging in Callicebus, which can have an important role in defining ecological strategies in the selection of secondary protein food resources within a given ecosystem. PMID:22311736

Deluycker, Anneke M

2012-05-01

386

Modelling foraging movements of diving predators: a theoretical study exploring the effect of heterogeneous landscapes on foraging efficiency  

PubMed Central

Foraging in the marine environment presents particular challenges for air-breathing predators. Information about prey capture rates, the strategies that diving predators use to maximise prey encounter rates and foraging success are still largely unknown and difficult to observe. As well, with the growing awareness of potential climate change impacts and the increasing interest in the development of renewable sources it is unknown how the foraging activity of diving predators such as seabirds will respond to both the presence of underwater structures and the potential corresponding changes in prey distributions. Motivated by this issue we developed a theoretical model to gain general understanding of how the foraging efficiency of diving predators may vary according to landscape structure and foraging strategy. Our theoretical model highlights that animal movements, intervals between prey capture and foraging efficiency are likely to critically depend on the distribution of the prey resource and the size and distribution of introduced underwater structures. For multiple prey loaders, changes in prey distribution affected the searching time necessary to catch a set amount of prey which in turn affected the foraging efficiency. The spatial aggregation of prey around small devices (? 9 × 9 m) created a valuable habitat for a successful foraging activity resulting in shorter intervals between prey captures and higher foraging efficiency. The presence of large devices (? 24 × 24 m) however represented an obstacle for predator movement, thus increasing the intervals between prey captures. In contrast, for single prey loaders the introduction of spatial aggregation of the resources did not represent an advantage suggesting that their foraging efficiency is more strongly affected by other factors such as the timing to find the first prey item which was found to occur faster in the presence of large devices. The development of this theoretical model represents a useful starting point to understand the energetic reasons for a range of potential predator responses to spatial heterogeneity and environmental uncertainties in terms of search behaviour and predator–prey interactions. We highlight future directions that integrated empirical and modelling studies should take to improve our ability to predict how diving predators will be impacted by the deployment of manmade structures in the marine environment. PMID:25250211

Barto?, Kamil A.; Scott, Beth E.; Travis, Justin M.J.

2014-01-01

387

Subjective costs drive overly patient foraging strategies in rats on an intertemporal foraging task  

PubMed Central

Laboratory studies of decision making often take the form of two-alternative, forced-choice paradigms. In natural settings, however, many decision problems arise as stay/go choices. We designed a foraging task to test intertemporal decision making in rats via stay/go decisions. Subjects did not follow the rate-maximizing strategy of choosing only food items associated with short delays. Instead, rats were often willing to wait for surprisingly long periods, and consequently earned a lower rate of food intake than they might have by ignoring long-delay options. We tested whether foraging theory or delay discounting models predicted the behavior we observed but found that these models could not account for the strategies subjects selected. Subjects’ behavior was well accounted for by a model that incorporated a cost for rejecting potential food items. Interestingly, subjects’ cost sensitivity was proportional to environmental richness. These findings are at odds with traditional normative accounts of decision making but are consistent with retrospective considerations having a deleterious influence on decisions (as in the “sunk-cost” effect). More broadly, these findings highlight the utility of complementing existing assays of decision making with tasks that mimic more natural decision topologies. PMID:23630289

Wikenheiser, Andrew M.; Stephens, David W.; Redish, A. David

2013-01-01

388

Foraging area fidelity for Kemp's ridleys in the Gulf of Mexico.  

PubMed

For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998-2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their "final" foraging sites. We identified new foraging "hotspots" where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water <68 m deep and a mean distance of 33.2 km (±25.3 SD) from the nearest mainland coast. Distance to release site, distance to mainland shore, annual mean sea surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13-year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at-sea foraging habitats for this imperiled species. PMID:23919146

Shaver, Donna J; Hart, Kristen M; Fujisaki, Ikuko; Rubio, Cynthia; Sartain, Autumn R; Peña, Jaime; Burchfield, Patrick M; Gamez, Daniel Gomez; Ortiz, Jaime

2013-07-01

389

Foraging area fidelity for Kemp's ridleys in the Gulf of Mexico  

PubMed Central

For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998–2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their “final” foraging sites. We identified new foraging “hotspots” where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water <68 m deep and a mean distance of 33.2 km (±25.3 SD) from the nearest mainland coast. Distance to release site, distance to mainland shore, annual mean sea surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13-year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at-sea foraging habitats for this imperiled species. PMID:23919146

Shaver, Donna J; Hart, Kristen M; Fujisaki, Ikuko; Rubio, Cynthia; Sartain, Autumn R; Peña, Jaime; Burchfield, Patrick M; Gamez, Daniel Gomez; Ortiz, Jaime

2013-01-01

390

Foraging depths of sea otters and implications to coastal marine communities  

USGS Publications Warehouse

We visually observed 1,251 dives, of 14 sea otters instrumented with TDRs in southeast Alaska, and used attribute values from observed dives to classify 180,848 recorded dives as foraging (0.64), or traveling (0.36). Foraging dives were significantly deeper, with longer durations, bottom times, and postdive surface intervals, and greater descent and ascent rates, compared to traveling dives. Most foraging occurred in depths between 2 and 30 m (0.84), although 0.16 of all foraging was between 30 and 100 m. Nine animals, including all five males, demonstrated bimodal patterns in foraging depths, with peaks between 5 and 15 m and 30 and 60 m, whereas five of nine females foraged at an average depth of 10 m. Mean shallow foraging depth was 8 m, and mean deep foraging depth was 44 m. Maximum foraging depths averaged 61 m (54 and 82 for females and males, respectively) and ranged from 35 to 100 m. Female sea otters dove to depths 20 m on 0.85 of their foraging dives while male sea otters dove to depths 45 m on 0.50 of their foraging dives. Less than 0.02 of all foraging dives were >55 m, suggesting that effects of sea otter foraging on nearshore marine communities should diminish at greater depths. However, recolonization of vacant habitat by high densities of adult male sea otters may result in initial reductions of some prey species at depths >55 m.

Bodkin, J.L.; Esslinger, G.G.; Monson, D.H.

2004-01-01

391

[Cytochemical characteristics of the labrocyte-like cells in the capsule of the plerocercoids of Triaenophorus nodulosus (Pallas, 1781) and Diphyllobothrium dendriticum (Nitzsch, 1824) cestodes].  

PubMed

Out of six fish species examined (Esox lucius, Paracottus kessleri, Perca fluviatilis, Leuciscus leuciscus baicalensis, Coregonus autumnalis migratorius, Thymallus arcticus baicalensis) labrocyte-like cells were detected in Esox lucius, Leuciscus leuciscus baicalensis, Coregonus autumnalis migratotius. The cells contain large metachromatic granules. Histochemical methods revealed in them sulfated and carboxylic acid mucopolysacharides. The amount of labrocyte-like cells in the capsules around plerocercoids of Triaenophrus nodulosis from Esox lucits liver depends on the age of the capsule and that of the plerocercoid. It increases when the connective tissue papsule is forming and decreases again under aging and degeneration of the capsule containing plerocercoid. The amount of labrocyte-like cells in the cestodes capsules of Raillietina increases sharply when they locate in an accidental organ (liver). This demonstrates the acuteness of organ reactivity to a nonspecific helminth. PMID:143258

Pronina, S V

1977-07-01

392

Foraging in corallivorous butterflyfish varies with wave exposure  

NASA Astrophysics Data System (ADS)

Understanding the foraging patterns of reef fishes is crucial for determining patterns of resource use and the sensitivity of species to environmental change. While changes in prey availability and interspecific competition have been linked to patterns of prey selection, body condition, and survival in coral reef fishes, rarely has the influence of abiotic environmental conditions on foraging been considered. We used underwater digital video to explore how prey availability and wave exposure influence the behavioural time budgets and prey selectivity of four species of obligate coral-feeding butterflyfishes. All four species displayed high selectivity towards live hard corals, both in terms of time invested and frequency of searching and feeding events. However, our novel analysis revealed that such selectivity was sensitive to wave exposure in some species, despite there being no significant differences in the availability of each prey category across exposures. In most cases, these obligate corallivores increased their selectivity towards their most favoured prey types at sites of high wave exposure. This suggests there are costs to foraging under different wave environments that can shape the foraging patterns of butterflyfishes in concert with other conditions such as prey availability, interspecific competition, and territoriality. Given that energy acquisition is crucial to the survival and fitness of fishes, we highlight how such environmental forcing of foraging behaviour may influence the ecological response of species to the ubiquitous and highly variable wave climates of shallow coral reefs.

Noble, Mae M.; Pratchett, Morgan S.; Coker, Darren J.; Cvitanovic, Christopher; Fulton, Christopher J.

2014-06-01

393

Fermentation patterns of forage sorghum ensiled under different environmental conditions.  

PubMed

The effects of temperature, aerobic and anaerobic conditions in the silo and plant characteristics [water-soluble carbohydrate (WSC) contents, growing season] on the fermentation characteristics of a tropical forage species, Sorghum bicolor cv. sugar-drip, were investigated. Silages fermented in oxygen-impermeable bags were well preserved and had low pH (3.7), high lactic acid [72 g kg(-1) dry matter (DM) ? 80% of total acids], and low butyric acid (0.12 g kg(-1) DM) and ammonia nitrogen (NH3-N) (57 g kg(-1) total nitrogen contents. Conversely, the use of oxygen-permeable bags as silos allowed aerobic decomposition of the ensiled forages. Increasing the incubation temperature lowered the population of lactic acid bacteria, reduced lactic acid production and caused the pH to rise. The heterofermentative Leuconostoc spp. predominated on fresh forages but homofermentative Lactobacillus plantarum began to dominate after 5 and 8 days of fermentation. Heterofermentative lactobacilli, notably Lactobacillus brevis, were dominant among the isolates obtained from 100-day silages. Varying the WSC contents, by crushing and/or chopping the forage, and growing season did not significantly affect the fermentation quality of the resulting silages. It was concluded that the maintenance of anaerobic conditions is essential if good quality silage is to be produced from tropical forage species. PMID:24424934

Tjandraatmadja, M; Norton, B W; Macrae, I C

1991-03-01

394

Perchlorate accumulation in forage and edible vegetation.  

PubMed

The accumulation of perchlorate in vegetation is becoming a concern, with increasing numbers of sites reporting the presence of perchlorate in groundwater and surface water. This study investigated potential perchlorate uptake and distribution by a variety of forage and edible crops in both the laboratory and the field. Perchlorate concentrations in soybean leaves grown in the greenhouse were significantly higher than perchlorate concentrations in soybean seeds and pods. Perchlorate concentrations in alfalfa grown in sand were significantly lower than those in alfalfa grown in soil. The concentration of perchlorate in tomato was lower in the fruit than the leaves. Commercially grown wheat and alfalfa samples all contained perchlorate, 0.72-8.6 mg/kg of fresh weight (FW) in the wheat stems, 0.71-4.4 mg/kg of FW in the wheat heads, and 2.9 mg/kg of FW in alfalfa. All field garden samples tested (including cucumber, cantaloupe, and tomato) that were irrigated with perchlorate-tainted water contained perchlorate at various concentrations ranging from 0.040 to 1.65 mg/kg of FW. Bioconcentration factors (BCF), ratios of plant fresh weight concentrations to estimated or measured groundwater concentrations [(microg/kg of FW)/microg/L], were all in the same order of magnitude ranging from 215 +/- 126 for wheat stems to 233 +/- 264 for wheat heads and to 380 +/- 89 for alfalfa. BCF for garden fruit samples were much lower (0.5-20). Results from this study highlight the potential for perchlorate exposure by routes other than drinking water. PMID:15656674

Jackson, W Andrew; Joseph, Preethi; Laxman, Patil; Tan, Kui; Smith, Philip N; Yu, Lu; Anderson, Todd A

2005-01-26

395

Chapter 7 Other Groundfish, Other Prohibited Species & Forage Fish Bering Sea Chinook Salmon Bycatch 411  

E-print Network

Bycatch 411 Final EIS ­ December 2009 7.0 OTHER GROUNDFISH, OTHER PROHIBITED SPECIES & FORAGE FISH & Forage Fish 412 Bering Sea Chinook Salmon Bycatch EIS Final EIS ­ December 2009 Incidental catch of some

396

7 CFR 407.13 - Area risk protection insurance for forage.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Area risk protection insurance for forage. 407...CORPORATION, DEPARTMENT OF AGRICULTURE AREA RISK PROTECTION INSURANCE REGULATIONS § 407.13 Area risk protection insurance for forage. The...

2014-01-01

397

Flower size preferences of the honeybee (Apis mellifera) foraging on Mimulus guttatus (Scrophulariaceae)  

E-print Network

Flower size preferences of the honeybee (Apis mellifera) foraging on Mimulus guttatus to differences in floral morphologies. I examined foraging preferences by the bee Apis mellifera (Apidae of M. guttatus. Keywords: Apis mellifera, flower size, Mimulus guttatus, pollination biology

Aspbury, Andrea S. - Department of Biology, Texas State University

398

Foraging reactivation in the honeybee Apis mellifera L.: factors affecting the return to known nectar sources  

NASA Astrophysics Data System (ADS)

This paper addresses, what determines that experienced forager honeybees return to places where they have previously exploited nectar. Although there was already some evidence that dance and trophallaxis can cause bees to return to feed, the fraction of unemployed foragers that follow dance or receive food from employed foragers before revisiting the feeder was unknown. We found that 27% of the experienced foragers had no contact with the returning foragers inside the hive. The most common interactions were dance following (64%) and trophallaxis (21%). The great variability found in the amount of interactions suggests that individual bees require different stimulation before changing to the foraging mode. This broad disparity negatively correlated with the number of days after marking at the feeder, a variable that is closely related to the foraging experience, suggesting that a temporal variable might affect the decision-making in reactivated foragers.

Gil, Mariana; Farina, Walter Marcelo

2002-05-01

399

Evidence of hypoxic foraging forays by yellow perch (Perca flavescens) and potential consequences for prey consumption  

E-print Network

Evidence of hypoxic foraging forays by yellow perch (Perca flavescens) and potential consequences and foraging patterns. For example, Lake Erie yellow perch (Perca flavescens) continue to consume benthic prey

400

The choice of foraging methods of the Brown Dipper, Cinclus pallasii (Aves: Cinclidae)  

Microsoft Academic Search

The Brown Dipper,Cinclus pallasii, forages for large prey by diving deeply among submerged rocks, and for small prey in shallow water by wading and pecking\\u000a on the bottom. Foraging by diving entailed a higher energy cost but resulted in taking larger prey than foraging by wading-and-pecking.\\u000a Foraging by diving was seldom observed from May to October, but increased from December

Kazuhiro Eguchi

1990-01-01

401

The effect of foraging specialization on various learning tasks in the honey bee ( Apis mellifera )  

Microsoft Academic Search

Honey bee foragers may collect nectar, pollen, water, or propolis, and their foraging specialization has been associated with\\u000a several behavioral traits. By conditioning of the proboscis extension response (PER), we compared the performance of foragers\\u000a that collected nectar, pollen, both nectar and pollen, or water in several learning and choice assays. Foragers were first\\u000a tested in a three-trial olfactory associative

Tamar Drezner-Levy; Brian H. Smith; Sharoni Shafir

2009-01-01

402

Acoustics as a tool for the assessment of Great Lakes forage fishes  

USGS Publications Warehouse

Sharp reductions in forage fish populations in Lake Michigan have raised concerns about the continued ability of the forage stocks to support large populations of lake trout and other salmonid predators. There was a need for a more comprehensive and accurate estimate of forage fish abundance and distribution to evaluate these concerns. In response, cooperative diel surveys of the Lake Michigan forage species were conducted in late summer 1987 and spring 1989 with acoustics, midwater and bottom trawls.

Argyle, Ray L.

1992-01-01

403

Spatio-temporal ranging behaviour and its relevance to foraging strategies in wide-ranging wolverines  

Microsoft Academic Search

Conservation of carnivores in an increasingly changing environment is greatly helped by understanding the decision-making processes underlying habitat patch choice. Foraging theory may give us insight into spatio-temporal search patterns and consequent foraging decisions that carnivores make in heterogeneous and fluctuating environments. Constraints placed on central-place foragers in particular are likely to influence both foraging decisions and related spatio-temporal movement

Roel May; Jiska van Dijk; Arild Landa; Roy Andersen; Reidar Andersen

2010-01-01

404

Long distance foraging and recruitment by a stingless bee, Melipona mandacaia  

Microsoft Academic Search

Body size is hypothesized to play a major role in animal foraging, particularly in pollinators. In general, species with larger\\u000a bodies forage over greater distances. Studies have found support for this body size-foraging range hypothesis across a wide\\u000a variety of pollinator species, but have not investigated the possibility that this effect also applies within a pollinator\\u000a species. We trained foragers

Brunno Kuhn-Neto; Felipe A. L. Contrera; Marina S. Castro; James C. Nieh

2009-01-01

405

Neuronal mechanism for acute mechanosensitivity in tactile-foraging waterfowl.  

PubMed

Relying almost exclusively on their acute sense of touch, tactile-foraging birds can feed in murky water, but the cellular mechanism is unknown. Mechanical stimuli activate specialized cutaneous end organs in the bill, innervated by trigeminal afferents. We report that trigeminal ganglia (TG) of domestic and wild tactile-foraging ducks exhibit numerical expansion of large-diameter mechanoreceptive neurons expressing the mechano-gated ion channel Piezo2. These features are not found in visually foraging birds. Moreover, in the duck, the expansion of mechanoreceptors occurs at the expense of thermosensors. Direct mechanical stimulation of duck TG neurons evokes high-amplitude depolarizing current with a low threshold of activation, high signal amplification gain, and slow kinetics of inactivation. Together, these factors contribute to efficient conversion of light mechanical stimuli into neuronal excitation. Our results reveal an evolutionary strategy to hone tactile perception in vertebrates at the level of primary afferents. PMID:25246547

Schneider, Eve R; Mastrotto, Marco; Laursen, Willem J; Schulz, Vincent P; Goodman, Jena B; Funk, Owen H; Gallagher, Patrick G; Gracheva, Elena O; Bagriantsev, Sviatoslav N

2014-10-14

406

The Müller-Lyer Illusion in Ant Foraging  

PubMed Central

The Müller-Lyer illusion is a classical geometric illusion in which the apparent (perceived) length of a line depends on whether the line terminates in an arrow tail or arrowhead. This effect may be caused by economic compensation for the gap between the physical stimulus and visual fields. Here, we show that the Müller-Lyer illusion can also be produced by the foraging patterns of garden ants (Lasius niger) and that the pattern obtained can be explained by a simple, asynchronously updated foraging ant model. Our results suggest that the geometric illusion may be a byproduct of the foraging process, in which local interactions underlying efficient exploitation can also give rise to global exploration, and that visual information processing in human could implement similar modulation between local efficient processing and widespread computation. PMID:24349117

Sakiyama, Tomoko; Gunji, Yukio-Pegio

2013-01-01

407

Elk winter foraging at fine scale in Yellowstone National Park.  

PubMed

The link between landscape properties and foraging decisions by herbivores remains unclear, but such knowledge is central to the understanding of plant-herbivore dynamics. Our goal was to determine whether fine-scale foraging paths of free-ranging elk (Cervus canadensis) respond to spatial structure of habitats in Yellowstone National Park. During winter 2002 we gathered elk-foraging information by following snow tracks in open habitats located on hillsides and flat terrain. The 21 snow paths surveyed were comprised on average of 15 discrete snow craters connected to each other by relatively straight-line movements. Our analyses revealed two levels of selection: elk chose where to dig, and how much search effort to allocate at digging sites based on habitat characteristics. On hillsides, elk preferentially dug in areas of greater biomass of grasses and forbs, and simply walked through poorer sites without digging. Individuals also searched more intensively, creating larger craters, where food biomass was higher. On flat terrain, crater size decreased with snow depth and increased with snow density. Correlated random walk models usually were adequate to characterize elk movement on flat terrain, but not on hillsides. First, as the number of movements between local foraging areas increased, elk displacements on hillsides became shorter than expected from random patterns. This trend on hillsides was strongly influenced by interindividual variation in movement behavior. Second, elk tended to forage perpendicularly to aspect, resulting in horizontal displacements. Our study demonstrates that free-ranging elk adjust their foraging to fine-scale habitat structure. PMID:15965755

Fortin, Daniel; Morales, Juan M; Boyce, Mark S

2005-09-01

408

The Lévy flight foraging hypothesis in a pelagic seabird.  

PubMed

1.Lévy flight foraging represents an innovative paradigm for the analysis of animal random search by including models of heavy-tailed distribution of move length which complements the correlated random walk paradigm that is founded on Brownian walks. Theory shows that the efficiency of the different foraging tactics is a function of prey abundance and dynamics with Lévy flight being especially efficient in poor prey fields. 2.Lévy flights have been controversial in some quarters, because they previously have been wrongly ascribed to many species through the employment of inappropriate statistical techniques and by misunderstanding movement pattern data. More recent studies using state-of-the-art statistical tools have, however, provided seemingly compelling evidence for Lévy flights. In this study, we employ these maximum-likelihood methods and their Bayesian equivalents by analysing both turning angles and move length distributions. 3.We tested, for compliance with Levy flight foraging, a set of 77 independent foraging trajectories of Cory's shearwaters Calonectris diomedea diomedea. Birds were tagged with high-resolution GPS loggers in two Mediterranean colonies (Linosa and Tremiti) during both incubation and chick-rearing. 4.We found that the behaviour of 6 birds was fitted by a correlated random walk, the movement of 32 birds was better represented by adaptive correlated random walks by switching from intensive to extensive searches, and the trajectories of 36 birds were fitted by a Lévy flight pattern of movement. The probability of performing Lévy flights was higher for trips during chick-provisioning when shearwaters were forced to forage in sub-optimal areas. This paper supports Levy flight foraging as an appropriate framework to analyze search tactics in this pelagic bird species and highlights that the adoption of a given search strategy is a function of biological and ecological constraints. This article is protected by copyright. All rights reserved. PMID:24102157

Focardi, Stefano; Cecere, Jacopo G

2013-09-18

409

Research Note Winter Forage Selection in White-Tailed Deer at High  

E-print Network

Research Note Winter Forage Selection in White-Tailed Deer at High Density: Balsam Fir is the Best forage selection by white-tailed deer (Odocoileus virginianus) on Anticosti Island, Quebec, Canada, using spruce, white-tailed deer, winter diet. Forage selection by wild herbivores may be determined

Laval, Université

410

Cold tolerance of forage legumes growing in controlled continental Mediterranean conditions  

Microsoft Academic Search

Summary - The growth of forage crops in Mediterranean areas is seriously limited by the dry summer but also by the cold winter. Potential forage species should be tested to improve the forage availability in these periods in which herbage production is limited. The objectives of this study were to compare seedling survival and viability in response to cold conditions

M. Sánchez-Díaz; M. Hekneby; M. C. Antolín

411

A Lightweight Secure Cyber Foraging Infrastructure for Resource-Constrained Sachin Goyal and John Carter  

E-print Network

A Lightweight Secure Cyber Foraging Infrastructure for Resource-Constrained Devices Sachin Goyal-constrained embedded and mobile devices are becoming increasingly common. Cyber foraging, which al- lows such devices the resources of less resource-constrained computers, a concept called surrogate computing or cyber foraging [15

Carter, John B.

412

OVERSEEDED FORAGE BRASSICA YIELD AND SUBSEQUENT GRASS SWARD RECOVERY IN APPALACHIAN HILL PASTURES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage brassicas can provide high-quality forage for small ruminants, but yields are affected by time of planting and sod-suppression may damage swards. We evaluated brassica yield and grass sward recovery in the subsequent year for forage rape (Brassica napus L.) and turnip (B. rapa L.) overseede...

413

Spatial arrangement, population density and legume species effect of yield of forage sorghum-legume intercropping  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sorghum (Sorghum bicolor) is a stress tolerant forage crop grown extensively in the Southern High Plains. However, sorghum forage quality is lower than that of corn. Intercropping sorghum with legumes can improve quality and productivity of forage. However, tall statured sorghum limits the resources...

414

NEW YORK FORAGE LEGUME AND GRASS VARIETY YIELD TRIALS SUMMARY FOR 2008 SEASON TOTALS  

E-print Network

NEW YORK FORAGE LEGUME AND GRASS VARIETY YIELD TRIALS SUMMARY FOR 2008 ­ SEASON TOTALS J. Hansen than in 2007), and perennial forage grass yields averaged 5.0 tons per acre dry matter (0.4 tons per should always be planted in combination with other forages like perennial grasses. Also, birdsfoot

Pawlowski, Wojtek

415

Foraging behavior predicts age at independence in juvenile Eurasian dippers ( Cinclus cinclus )  

Microsoft Academic Search

Timing of foraging independence may be controlled by parents, offspring, or both and may have consequences for dispersal, reproduction, and survival. In a study of juvenile Eurasian dippers {Cinclus cinclus), I examined the relationship between individual differences in parental provisioning, the development of foraging, and the liming of independence. Young dippers forage very differently from adults, specializing on small, stationary

Sonja I. Yoerg

1998-01-01

416

Short- and Long-Term Economic Analysis of Forage Mixtures and Grazing Strategies  

Technology Transfer Automated Retrieval System (TEKTRAN)

The use of complex forage mixtures (mixtures of more than three species) has been researched as a means to increase yield and sustain forage production in pastures of the northeastern USA. However, little research has focused on the economic impact of forage mixture complexity and grazing strategy o...

417

A distance-dependent estimation of foraging ranges of neighbouring bird colonies  

Microsoft Academic Search

A reliable estimation of foraging ranges is often an indispensable prerequisite of research in animal ecology and in species conservation. In colonial species, home ranges of members of one colony are frequently overlapping and for practical and theoretical reasons, it can be necessary to assess the foraging areas of whole colonies. Here, we show a method to calculate foraging areas

Erwin Nemeth; Peter Bossew; Christoph Plutzar

2005-01-01

418

Optimal Resource Allocation to Survival and Reproduction in Parasitic Wasps Foraging in  

E-print Network

Optimal Resource Allocation to Survival and Reproduction in Parasitic Wasps Foraging in Fragmented and environmental variability affect the optimal reproductive strategies of parasitic wasps foraging for hosts in Parasitic Wasps Foraging in Fragmented Habitats. PLoS ONE 7(6): e38227. doi:10.1371/journal.pone.0038227

Paris-Sud XI, Université de

419

Daily foraging schedule of field colonies of the eastern tent caterpillar Malacosoma americanum  

Microsoft Academic Search

The daily foraging patterns of seven colonies of the eastern tent caterpillar, Malacosoma americanum, were monitored photoelectronically during the last three larval stadia to provide the first detailed record of the foraging behavior of a gregarious caterpillar under field conditions. Colonies were active an average of 49.3% of each day. Three bouts of foraging, centered about 0600 h, 1500 h

T. D. Fitzgerald; Tim Casey; Barbara Joos

1988-01-01

420

Foraging pattern of pine siskins and its influence on winter moth survival in an apple orchard  

Microsoft Academic Search

Foraging by migratory pine siskins in an apple orchard infested with varying densities of winter moth was observed, and winter moth mortality in the presence and absence of birds was recorded. Time spent foraging in a tree and number of birds foraging per tree was positively related to larval density but number of larvae removed per leaf cluster or per

Jens Roland; Susan J. Hannon; M. Angela Smith

1986-01-01

421

Nonconsumptive effects in a multiple predator system reduce the foraging efficiency of a keystone predator  

E-print Network

of experiments with larval dragonflies, adult newts (a known keystone predator), and their tadpole prey. We tadpoles to hide under leaf litter (a NCE), where newts spend less time foraging, which reduced the forag- ing success (CE) of newts. Newts altered tadpole behavior but not in a way that altered the foraging

Chalcraft, David R.

422

Patches of Bare Ground as a Staple Commodity for Declining Ground-Foraging Insectivorous Farmland Birds  

E-print Network

Patches of Bare Ground as a Staple Commodity for Declining Ground-Foraging Insectivorous Farmland is the status of insectivorous farmland birds that forage on the ground. We modelled the foraging habitat preferences of four declining insectivorous bird species (hoopoe, wryneck, woodlark, common redstart

Richner, Heinz

423

FORAGING ECOLOGY OF EPIPHYTE-SEARCHING INSECTIVOROUS BIRDS IN COSTA RICA1  

Microsoft Academic Search

Foraging ecology and diet of eight species of epiphyte-searching insectivorous birds were studied in the Talamanca mountains of Costa Rica to determine degree of epiphyte specialization. To measure species' selectivity for epiphytic substrates, quantitative data on epiphyte availability was compared to actual bird use of epiphytes. Associations between each species and its foraging substrates, foraging maneuvers, and diets suggested a

T. SCOTT SILLETT

424

The use and misuse of public information by foraging red crossbills  

Microsoft Academic Search

Group foragers may assess patch quality more efficiently by paying attention to the sampling behavior of group members foraging in the same patch (i.e., using ''public information''). To determine whether red crossbills (Loxia curvirostra) use public infor- mation to aid their patch departure decisions, we conducted experiments that compared the sampling behavior of crossbills foraging on a two-patch system (one

Julie W. Smith; Craig W. Benkman; Kimberly Coffey

1999-01-01

425

Diurnal and individual variability in the foraging behavior of American redstarts ( Setophaga ruticilla )  

Microsoft Academic Search

The foraging behavior of American redstarts, Setophaga ruticilla (Aves: Parulidae), was examined from dawn to dusk in the nestling phase of their breeding cycle in a northern hardwoods forest in New Hampshire, USA. Based on a sample size of nearly 3000 foraging acts, we found that redstarts hawked more and foraged lower at midday than early in the morning, coincident

R. T. Holmes; T. W. Sherry; S. E. Bennett

1978-01-01

426

Rodent foraging is affected by indirect, but not by direct, cues of predation risk  

Microsoft Academic Search

We used foraging trays to determine whether oldfield mice, Peromyscus polionotus, altered foraging in response to direct cues of predation risk (urine of native and nonnative predators) and indirect cues of predation risk (foraging microhabitat, precipitation, and moon illumination). The proportion of seeds remaining in each tray (a measure of the giving-up density [GUD]) was used to measure risk perceived

John L. Orrock; Brent J. Danielson; R. Jory Brinkerhoffb; R. Brinkerhoff; Jory

2004-01-01

427

Specialization and development of beach hunting, a rare foraging behavior, by wild bottlenose dolphins ( Tursiops sp.)  

Microsoft Academic Search

Foraging behaviors of bottlenose dolphins vary within and among populations, but few studies attempt to ad- dress the causes of individual variation in foraging behavior. We examined how ecological, social, and developmental factors relate to the use of a rare foraging tactic by wild bottlenose dolphins (Tursiops sp. Gervais, 1855) in Shark Bay, Western Australia. Beach hunting involves partial and

B. L. Sargeant; J. Mann; P. Berggren; M. Krützen

2005-01-01

428

[Study on foraging behaviors of honeybee Apis mellifera based on RFID technology].  

PubMed

Honeybee foragers can flexibly adjust their out-hive activities to ensure growth and reproduction of the colony. In order to explore the characteristics of honey bees foraging behaviors, in this study, their flight activities were monitored 24 hours per day for a duration of 38 days, using an radio frequency identification (RFID) system designed and manufactured by the Honeybee Research Institute of Jiangxi Agricultural University in cooperation with the Guangzhou Invengo Information Technology Co., Ltd. Our results indicated that 63.4% and 64.5% of foragers were found rotating more than one day off during the foraging period in two colonies, and 22.5% and 26.4% of the total foraging days were used for rest respectively. Further, although the total foraging time between rotating day-off foragers and continuously working foragers was equal, the former had a significant longer lifespan than the latter. Additionally, the lifespan of the early developed foragers was significantly lower than that of the normally developed foragers. This study enriched the content of foraging behaviors of honey bees, and it could be used as the basis for the further explorations on evolutionary mechanism of foraging behaviors of eusocial insects. PMID:24984504

Tian, Liu-Qing; He, Xu-Jiang; Wu, Xiao-Bo; Gan, Hai-Yan; Han, Xu; Liu, Hao; Zeng, Zhi-Jiang

2014-03-01

429

Effects of human activity on the foraging behavior of sanderlings Calidris alba  

Microsoft Academic Search

Urbanization and coastal development has dramatically reduced the beach habitat available for foraging shorebirds worldwide. This study tested the general hypothesis that recreational use of shorebird foraging areas adversely affects the foraging behavior of sanderlings Calidris alba. Observations conducted on two central California beaches from January through May and September through December of 1999 showed that number and activity of

Kate Thomas; Rikk G Kvitek; Carrie Bretz

2003-01-01

430

Research article Bumble bee olfactory information flow and contact-based foraging activation  

E-print Network

Research article Bumble bee olfactory information flow and contact-based foraging activation M in foraging activation is poorly understood in bumble bees, as compared to honey bees and stingless bees. We therefore investigated olfactory information flow and foraging activation in the New World bumble bee

Nieh, James

431

Resource diversity and landscape-level homogeneity drive native bee foraging  

E-print Network

Resource diversity and landscape-level homogeneity drive native bee foraging Shalene Jhaa,b,1 of a critical native pollinator, Bombus vosnesenskii. Our findings demonstrate that native bee foraging is far strat- egy. Rather, bumble bees forage further in pursuit of species-rich floral patches

432

FORAGING BEHAVIOR AND MONETARY IMPACT OF WADING BIRDS AT ARKANSAS BAITFISH FARMS  

Technology Transfer Automated Retrieval System (TEKTRAN)

We conducted foraging observations, food habits studies, and producer surveys to determine the foraging behavior and monetary impact of great blue herons Ardea herodias, great egrets A. alba, and little blue herons Egretta caerulea foraging at Arkansas baitfish farms. Although great egrets captured...

433

Foraging behaviour of western sandpipers changes with sediment temperature: implications for their hemispheric distribution  

Microsoft Academic Search

Migratory shorebirds need to replenish their energy reserves by foraging at stop-over sites en route. Adjusting their foraging behaviour to accommodate variation in local prey availability would therefore be advantageous. We test whether western sandpipers (Calidris mauri), a sexually dimorphic shorebird, adjust their foraging behaviour in response to local changes in prey availability, as inferred by changes in diurnal time

Silke Nebel; Graham J. Thompson

2005-01-01

434

Foraging time and dietary intake by breeding Ross's and Lesser Snow Geese  

Microsoft Academic Search

We compared foraging times of female Ross's (Chen rossii) and Lesser Snow Geese (Chen caerulescens caerulescens) breeding at Karrak Lake, NT, Canada and examined variation due to time of day and reproductive stage. We subsequently collected female geese that had foraged for known duration and we estimated mass of foods consumed during foraging bouts. Female Ross's Geese spent more time

Mark L. Gloutney; Ray T. Alisauskas; Alan D. Afton; Stuart M. Slattery

2001-01-01

435

Foraging modes of stream benthic fishes in relation to their predation effects on local prey density  

Microsoft Academic Search

Habitat use and foraging behavior of two benthic insectivorous gobies, Rhinogobius sp. CO (cobalt type) and Rhinogobius sp. DA (dark type), were examined in relation to their predation effects on local prey density in a small coastal stream in southwestern Shikoku, Japan. Correlations among the foraging range, frequency of foraging attempts and current velocity indicated that individuals using fast-current habitats

Mikio Inoue; Masanobu Miyayoshi; Shin Sone

2005-01-01

436

FORBEEF: A Forage-Livestock System Computer Model Used as a Teaching Aid for Decision Making.  

ERIC Educational Resources Information Center

Describes the development of a computer simulation model of forage-beef production systems, which is intended to incorporate soil, forage, and animal decisions into an enterprise scenario. Produces a summary of forage production and livestock needs. Cites positive assessment of the program's value by participants in inservice training workshops.…

Stringer, W. C.; And Others

1987-01-01

437

A Preliminary Investigation into Forage Quality Attributes of Several Native Eastern Savanna Species  

Technology Transfer Automated Retrieval System (TEKTRAN)

Introduction: Nutritive attributes of traditional forages are well documented, and benefits of forage condensed tannins (CT) for ruminants have been the subject of numerous investigations. The number of tanniferous forage species that are adapted to humid, temperate climates is limited, and the ro...

438

Mathematical Model of Foraging in a Group of Robots: Effect of Interference  

Microsoft Academic Search

In multi-robot applications, such as foraging or collection tasks, interference, which results from com- petition for space between spatially extended robots, can significantly affect the performance of the group. We present a mathematical model of foraging in a homogeneous multi-robot system, with the goal of understanding quantitatively the effects of interference. We examine two foraging scenarios: a simplified collection task

Kristina Lerman; Aram Galstyan

2002-01-01

439

Colony state and regulation of pollen foraging in the honey bee, Apis mellifera L  

Microsoft Academic Search

To place social insect foraging behavior within an evolutionary context, it is necessary to establish relationships between individual foraging decisions and parameters influencing colony fitness. To address this problem, we examined interactions between individual foraging behavior and pollen storage levels in the honey bee, Apis mellifera L. Colonies responded to low pollen storage conditions by increasing pollen intake rates 54%

Jennifer H. Fewell; Mark L. Winston

1992-01-01

440

RESEARCH ARTICLE Individual forager profits in Apis mellifera unaffected by a range  

E-print Network

RESEARCH ARTICLE Individual forager profits in Apis mellifera unaffected by a range of colony foraging time. We conclude that individual forager profits in Apis mellifera are unaffected by the range Apis mellifera, the ectoparasitic mite Varroa destructor Anderson and Trueman is distinctively virulent

Delaplane, Keith S.

441

Differences in foraging and broodnest temperature in the honey bees Apis cerana and A. mellifera  

E-print Network

Differences in foraging and broodnest temperature in the honey bees Apis cerana and A. mellifera Abstract ­ This study aims to explore the effect of ambient temperature on foraging the activity of Apis cerana and Apis mellifera colonies. We recorded ambient temperature, the time at which foraging commenced

442

PLECTRANTHUS AS FORAGE FOR APIS CERANA INDICA F. AND APIS MELLIFERA L.  

E-print Network

PLECTRANTHUS AS FORAGE FOR APIS CERANA INDICA F. AND APIS MELLIFERA L. J.K. GUPTA, R.C. MISHRA.c. inclica foragers worked for longer hours than A. mellifera. A single A.c. indica forager visited 17 an apiary with both Apis cerana indica F. and A, mellijera L. colonies. (The number of A.c. indica and A

Boyer, Edmond

443

GENETIC VARIABILITY FOR MINERAL CONCENTRATION IN THE FORAGE OF JERUSALEM ARTICHOKE CULTIVARS  

Technology Transfer Automated Retrieval System (TEKTRAN)

One of the potential uses of Jerusalem artichoke (Helianthus tuberosus L.) is as a forage crop. Information on inherent differences in forage nutritional quality is essential if the quality of the forage is to be improved through breeding. The objectives of this study were to determine the genotypic...

444

GENETIC VARIABILITY FOR MINERAL ELEMENT CONCENTRATIONS OF WILD JERUSALEM ARTICHOKE FORAGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

One of the potential uses of Jerusalem artichoke (Helianthus tuberosus L.) is as a forage crop. Information on inherent differences in forage nutritional quality is essential if the quality of the forage is to be improved through breeding. The objectives of this study were to determine the genotypic...

445

POLLEN MAKES BEES HOT Forager bees like nothing more than a  

E-print Network

Inside JEB iii POLLEN MAKES BEES HOT Forager bees like nothing more than a sweet supply of nectar. But bees do not live by nectar alone. One of their main sources of protein is pollen. Knowing that bees% pollen protein samples and offered them to a bee colony in an isolated foraging arena. Measuring foraging

Nieh, James

446

Bumble bee pollen foraging regulation: role of pollen quality, storage levels, and odor  

E-print Network

ERRATUM Bumble bee pollen foraging regulation: role of pollen quality, storage levels, and odor T was made to the article title. The correct title should read: Bumble bee pollen foraging regulation: role for Behavioral Ecology and Sociobiology Bumble bee pollen foraging regulation: role of pollen quality, storage

Nieh, James

447

Fatty Acid Composition of Mixed-Rumen Bacteria: Effect of Concentration and Type of Forage  

Microsoft Academic Search

The effects of concentration and type of forage in the diet on lipid content and fatty acid (FA) composition of rumen bacteria were studied in 14 goats fitted with duodenal cannulas. The goats were fed a complete maintenance diet containing 40, 70, or 100% chopped forage (dry matter basis) in two equal meals. Forage was either corn stover or alfalfa

P. Bas; H. Archimède; A. Rouzeau; D. Sauvant

2003-01-01

448

Auto-Clustering Using Particle Swarm Optimization and Bacterial Foraging  

NASA Astrophysics Data System (ADS)

This paper presents a hybrid approach for clustering based on particle swarm optimization (PSO) and bacteria foraging algorithms (BFA). The new method AutoCPB (Auto-Clustering based on particle bacterial foraging) makes use of autonomous agents whose primary objective is to cluster chunks of data by using simplistic collaboration. Inspired by the advances in clustering using particle swarm optimization, we suggest further improvements. Moreover, we gathered standard benchmark datasets and compared our new approach against the standard K-means algorithm, obtaining promising results. Our hybrid mechanism outperforms earlier PSO-based approaches by using simplistic communication between agents.

Olesen, Jakob R.; Cordero H., Jorge; Zeng, Yifeng

449

Effects of ardacin on grazed forage utilization by calves  

E-print Network

and . 59, P=. 06) and ruminal microbial protein synthesis efficiency (MPE, 20. 4, 21. 1 and 18. 8 g of microbial protein per 100 g of OM digested in the rumen, P=. 09). The greater gain responses to DA in LP vs HP (Exp. 2) and on pastures of lower... of protein. The occurrence of nutritional deficiencies in calves grazing high quality forages may be explained as the result of inefficient digestive utilization. Since proteins of freshly grazed forage are extensively fermented in the rumen...

Ysunza Bren?a, Francisco Juan

2012-06-07

450

Forage production and animal performance from Kenhy tall fescue  

E-print Network

ava1lable under grazing. Crude protein of the forage with1n the cages (Appendix Table A2) was the same as forage available during the fall and winter periods but rose to higher levels during the spr1ng growth period. Crude protein ranged from 5. 3K... but somewhat static IVDOM level was observed throughout the fall and winter per1od with a rap1d rise as spr1ng growth started. Grab samples made at each cl1pping interval were higher in CP and IVDOM than other samples w1thin the same pasture during...

Dorsett, D. J

2012-06-07

451

The effects of drought on Ngatatjara plant use: An evaluation of optimal foraging theory  

SciTech Connect

The different responses of plants to drought conditions are examined in the Western Desert of Australia to demonstrate the necessity of considering plant food availability prior to optimal foraging applications involving human hunter-gatherers. The correspondence of Ngatatjara dietary breadth changes to optimal foraging predictions is explained as an adaptive response to the unpredictable Western Desert reinfall. By minimizing the time allocated to food procurement, energy-efficient foraging reduces the risk involved in the exploitation of scattered, ephemeral water sources. Futher applications of optimal foraging models to hunter-gatherers is one line of promising investigation to address behavioral variability among human foragers.

Pate D.

1986-03-01

452

Age and hunting success in the brown pelican: influences of skill and patch choice on foraging efficiency  

Microsoft Academic Search

Age-related differences in the foraging efficiency of piscivorous birds may be the results of differences in foraging skill, patch usage, or both. Brown pelicans were observed while foraging around a small Caribbean island. Areas where the birds fed were subdivided into small, homogeneous subunits (patches), and the bird's foraging success and patch use were noted and analyzed using multivariate techniques.

C. A. Brandt

1984-01-01

453

Foraging by bats in cleared, thinned and unharvested boreal forest  

Microsoft Academic Search

Summary 1. Modern silvicultural methods employ various styles of selective harvesting in addi- tion to traditional clear-cutting. This can create a mosaic of patches with different tree densities that may influence habitat use by foraging bats. Use of forest patches may also vary among bat species due to variation in their manoeuvrability. Apart from studies investigating use of clear-cuts, few

Krista J. Patriquin; Robert M. R. Barclay

2003-01-01

454

FORAGE ENERGY CROPS AS FEEDSTOCKS FOR PRODUCTION OF FUEL ETHANOL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alfalfa, reed canarygrass, and switchgrass are perennial herbaceous species that have potential as biomass energy crops in temperate regions. Each forage species was harvested at two or three maturity stages and analyzed for carbohydrates, lignin, protein, lipid, organic acids, and mineral composit...

455

ORIGINAL ARTICLE Collective decisions in ants when foraging  

E-print Network

ORIGINAL ARTICLE Collective decisions in ants when foraging under crowded conditions Audrey-recruiting ant Lasius niger. In our experiment, ants had to go from their nest to a food source by crossing underlying the choice of route in ants. A mathematical model was developed to evaluate the impor- tance

Nicolis, Stamatios C.

456

Nutritive value response of forage chicory cultivars to phosphorus fertility  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage chicory (Cichorium intybus L.) is a productive plant that appears particularly well suited to improving summer yield of pastures in the USA. Poor palatability of some chicory cultivars in locations with low soil phosphorus fertility has been linked to high levels of sesquiterpene lactones, b...

457

Response of Forage Chicory Seedlings to Available Soil Phosphorus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Phosphorus fertility may be responsible for observed differences in chemical composition of forage chicory (Cichorium intybus L.) on West Virginia and Pennsylvania soils, but P effects on chicory growth on these soils are unclear. We evaluated the effect of available soil P (ASP) on ‘Puna’, ‘Lacert...

458

POLYPHENOL AND CONDITIONING EFFECTS ON FORAGE PROTEIN SOLUBILITY AND DEGRADABILITY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Increasing the degree of tissue disruption during mechanical harvesting of forages may augment protein interactions with polyphenols and other cellular constituents, enhancing protein utilization by reducing protein solubility and shifting its degradation from the rumen to the intestine. In 2002 and...

459

Potential energetic effects of mountain climbers on foraging grizzly bears  

USGS Publications Warehouse

Most studies of the effects of human disturbance on grizzly bears (Ursus arctos horribilis) have not quantified the energetic effects of such interactions. In this study, we characterized activity budgets of adult grizzly bears as they foraged on aggregations of adult army cutworm moths (Euxoa auxiliaris) in the alpine of Glacier National Park, Montana, during 1992, 1994, and 1995. We compared the activity budgets of climber-disturbed bears to those of undisturbed bears to estimate the energetic impact of climber disturbance. When bears detected climbers, they subsequently spent 53% less time foraging on moths, 52% more time moving within the foraging area, and 23% more time behaving aggressively, compared to when they were not disturbed. We estimated that grizzly bears could consume approximately 40,000 moths/day or 1,700 moths/hour. At 0.44 kcal/moth, disruption of moth feeding cost bears approximately 12 kcal/minute in addition to the energy expended in evasive maneuvers and defensive behaviors. To reduce both climber interruption of bear foraging and the potential for aggressive bear-human encounters, we recommend routing climbers around moth sites used by bears or limiting access to these sites during bear-use periods.

White, D., Jr.; Kendall, K.C.; Picton, H.D.

1999-01-01

460

Efficiency Evaluation of Two Competing Foraging Modes under Different Conditions  

Microsoft Academic Search

Various foraging modes are employed by predators in nature, ranging from ambush to active predation. Although the for- aging mode may be limited by physiological constraints, other factors, such as prey behavior and distribution, may come into play. Using a simulation model, we tested to what extent the relative success of an ambush and an active predator changes as a

Inon Scharf; Einat Nulman; Ofer Ovadia; Amos Bouskila

2006-01-01

461

Nitrogen fixation in six forage legumes in Mediterranean central Chile  

Microsoft Academic Search

The contribution of biological nitrogen fixation (BNF) to the N nutrition of six annual forage legumes, subterranean clover (Trifolium subterraneum), burr medic (Medicago polymorpha), balansa clover (Trifolium michelianum), Persian clover (Trifolium resupinatum), yellow serradela (Ornithopus compressus), and pink serradela (Ornithopus sativus) was evaluated by the N natural abundance technique, using four grass species (Briza máxima, Bromus mollis, Hordeum berteroanum,Avena barbata)

C. Ovalle; S. Urquiaga; A. Del Pozo; E. Zagal; S. Arredondo

2006-01-01

462

The Value of Uncropped Field Margins For Foraging Bumblebees  

Microsoft Academic Search

The intensification of agriculture has led to declines in species diversity and abundance within groups of certain flora and fauna. Bumblebees (Bombus spp.) are one group where a decline has been documented, and it is thought to be attributable to a decrease in forage resources and potential nest sites. As bumblebees play an important role in the pollination of many

Andrea R. Kells; John M. Holland; Dave Goulson

2001-01-01

463

Forage subsurface drip irrigation using treated swine effluent  

Technology Transfer Automated Retrieval System (TEKTRAN)

An experimental subsurface drip irrigation (SDI) system was initiated to evaluate the use of treated swine effluent on a bermuda grass forage crop. The SDI system was installed in Duplin County, North Carolina, at the location of an innovative swine wastewater treatment system. The effluent from the...

464

FORAGE SUBSURFACE DRIP IRRIGATION USING TREATED SWINE EFFLUENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

An experimental subsurface drip irrigation (SDI) system was initiated to evaluate the use of treated swine effluent on a bermuda grass forage crop. The SDI system was installed in Duplin County, North Carolina, at the location of an innovative swine wastewater treatment system. The effluent from the...

465

FORAGE YIELD AND PERSISTENCE OF CHICORY AND ENGLISH PLANTAIN  

Technology Transfer Automated Retrieval System (TEKTRAN)

Graziers in the northeast often face forage shortages in midsummer. Chicory (Cichorium intybus L.) and English plantain (Plantago lanceolata L.) have been introduced in the USA as perennial herbs for pastures and have been touted as drought tolerant. We conducted two field-plot experiments at Rock S...

466

Individual Cognitive Parameter Setting Based on Black Stork Foraging Process  

Microsoft Academic Search

Abstract—Cognitive learning factor is an important param- eter in particle swarm optimization algorithm(PSO). Although many selection strategies have been proposed, there is still much work need to do. Inspired by the black stork foraging process, this paper designs a new cognitive selection strategy, in which the whole swarm is divided into adult and infant particle, and each kind particle has

Zhihua Cui

2009-01-01

467

A new modified PSO based on black stork foraging process  

Microsoft Academic Search

Cognitive parameter plays an important role in particle swarm optimization. Although many cognitive parameter selection strategies are proposed, there is still much work need to do. This paper proposes an individual cognitive parameter setting method by simulating the black stork foraging process. It chooses the cognitive value of each particle associated with its age dominated by its performance. For particles

Xingjuan Cai

2009-01-01

468

ORGANOCHLORINE CONTAMINANTS OF WINTERING DUCKS FORAGING ON DETROIT RIVER SEDIMENTS  

EPA Science Inventory

Organochlorine analysis was performed on carcasses of 13 diving ducks from a 1981 wintering population that foraged on contaminated sediments in the lower Detroit River. Mean total PCB concentrations were 10 mg/kg for seven lesser scaups (Aythya affinis), 11 mg/kg for three great...

469

Adaptive foraging and flexible food web topology Vlastimil Krivan  

E-print Network

modelling shows that single systems of predators, adaptive herbivores and resources can display food chain, adaptive omnivory causes the exploitative competition, linear food chain and multi-trophic level omnivory be confounded by topological shifts in the system itself. Keywords: adaptive foraging, food chain, food web

Krivan, Vlastimil

470

Effect of Precipitation During Key Months on Forage Growth Potential  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ranchers and range managers find themselves at the mercy of Mother Nature when making stocking decisions early in the spring. Most forage growth potential is determined by precipitation during key months in the spring (Heitschmidt et al., 1999) – often multiple spring months are important with resp...

471

Nutritional Toxicology of Tannins and Related Polyphenols in Forage Legumes  

Microsoft Academic Search

Proanthocyanidins (PA) (condensed tannins) and hydrolyzable tannins (HT) are the two major classes of tannins. Proanthocyanidins are flavo- noid polymers. Hydrolyzable tannins are polymers of gallic or ellagic acid esterified to a core molecule, commonly glucose or a polyphenol such as catechin. Proanthocyanidins are the most common type of tannin found in forage legumes. Problems in the analysis of tannins

Jess D. Reed

2010-01-01

472

Allocating Great Lakes forage bases in response to multiple demand  

USGS Publications Warehouse

Forage base allocation, which has become an important issue because of major changes in the fish communities and fisheries of the Great Lakes since the 1950s is examined and documented in this chapter. Management initiatives that were used to address the issue, and supporting research and development that provided new or improved methods of field sampling and analysis are also highlighted.

Brown, Edward H., Jr.; Busiahn, Thomas R.; Jones, Michael L.; Argyle, Ray L.

1999-01-01

473

OPTIMAL FORAGING BY LARGEMOUTH BASS IN STRUCTURED ENVIRONMENTS  

EPA Science Inventory

The effects of different densities of vegetation on the foraging behavior of largemouth bass, Micropterus salmoides, were examined in the laboratory. Prey encounter rates and handling times and the swimming velocities of the bass while searching for and handling prey were signifi...

474

ORIGINAL PAPER Foraging habitats of Myotis emarginatus in Central Europe  

E-print Network

% of the total forest area, but only 10% of the foraging areas were located in this forest type. Deciduous, the availability of native deciduous forest and of fly-infested stables within a radius of 6 km around the colony . Deciduous forests . Spruce monoculture . Behaviour. Cow shed Introduction Myotis emarginatus is regarded

Paris-Sud XI, Université de

475

Effects of humic acid on forage digestibility in ruminants  

E-print Network

Three experiments were conducted to determine the effects of purified humic acid (HA) on rate and extent of microbial digestion of various forages in ruminants. In Exp. 1 the in vitro dry matter disappearance (DMD) of Coastal Bermuda grass hay (CBH...

Faulkenbery, James Marcus

1995-01-01

476

Marker Selection Strategies for Forage, Turf, and Biofuels  

Technology Transfer Automated Retrieval System (TEKTRAN)

Genetic improvement of forage, turf, and biofuel crops requires rapid, inexpensive, and repeatable measurement of plant phenotypes. For many important traits, such as biomass yield, abiotic stress tolerances, resistance to some disease pathogens, and long-term persistence, inability to accurately m...

477

Relay seeding forage species in rice systems in Bhutan  

Microsoft Academic Search

Integrating forage legumes into existing rice production systems in the Himalayas could contribute towards sustaining soil fertility and diversifying production. Technologies need to be refined, especially species selection and estab- lishment, before they can be recommended to farmers. From 1996-99 various studies were carried out across a range of conditions (eleva- tion 300-2500 m) to evaluate effects of species, establishment

W. RODER; P. WANGCHUK; S. THSERING

478

Genomic selection in forage breeding: accuracy and methods  

Technology Transfer Automated Retrieval System (TEKTRAN)

The main benefits expected from genomic selection in forage grasses and legumes are to increase selection accuracy, reduce evaluation costs per genotype, and reduce cycle time. Aiming at designing a training population and first generations of selection, deterministic equations were used to compare ...

479

Foraging Ecology Predicts Learning Performance in Insectivorous Bats  

E-print Network

Foraging Ecology Predicts Learning Performance in Insectivorous Bats Theresa M. A. Clarin1 insectivorous European bat species of the genus Myotis that belong to three different functional groups based Ecology Predicts Learning Performance in Insectivorous Bats. PLoS ONE 8(6): e64823. doi:10.1371/journal

Page, Rachel

480

Relationships between digestibility and cell wall structure of forage maize  

E-print Network

Relationships between digestibility and cell wall structure of forage maize JM Besle V Serre MP studied in maize whole crop. Whole plants of normal maize were collected at six stages after flowering (1 by the heterogeneity and complexity of whole maize, but the phenylpropanoid components can be utilized to predict

Paris-Sud XI, Université de

481

In Vitro Digestion Rate of Forage Cell Wall Components  

Microsoft Academic Search

Linearity of the semilog plots of remain- ing digestible fiber on time and their corre- lations (r = .98 approximately) indicated first order digestion kinetics for each of the six forages even though composition and observed rates of fiber digestion were markedly different. Immature rye cell walls digested fastest (27.03 ± .81%\\/ hour, r 2 -- .999) and mature timothy

L. W. Smith; H. K. Goering; D. R. Waldo; C. H. Gordon

1971-01-01

482

Sampling requirements for forage quality characterization of rectangular hay bales  

SciTech Connect

Commercial lots of alfalfa (Medicago sativa L.) hay are often bought and sold on the basis of forage quality. Proper sampling is essential to obtain accurate forage quality results for pricing of alfalfa hay, but information about sampling is limited to small, 20- to 40-kg rectangular bales. Their objectives were to determine the within-bale variation in 400-kg rectangular bales and to determine the number and distribution of core samples required to represent the crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), and dry matter (DM) concentration in commercial lots of alfalfa hay. Four bales were selected from each of three hay lots and core sampled nine times per side for a total of 54 cores per bale. There was no consistent pattern of forage quality variation within bales. Averaged across lots, any portion of a bale was highly correlated with bale grand means for CP, ADF, NDF, and DM. Three lots of hay were probed six times per bale, one core per bale side from 55, 14, and 14 bales per lot. For determination of CP, ADF, NDF, and DM concentration, total core numbers required to achieve an acceptable standard error (SE) were minimized by sampling once per bale. Bootstrap analysis of data from the most variable hay lot suggested that forage quality of any lot of 400-kg alfalfa hay bales should be adequately represented by 12 bales sampled once per bale.

Sheaffer, C.C.; Martin, N.P.; Jewett, J.G.; Halgerson, J.; Moon, R.D.; Cuomo, G.R.

2000-02-01

483

Using glycerin as a supplement for forage-fed ruminants.  

Technology Transfer Automated Retrieval System (TEKTRAN)

The utility of crude glycerin as a feed additive for forage–fed ruminants depends largely on how well the animals are able to utilize the glycerol and other dietary components when crude glycerin is added to the diet. Several studies have demonstrated that ruminal fermentation of pure glycerol resul...

484

IMPACT OF ALFALFA GROWTH AND DEVELOPMENT ON FORAGE QUALITY TRAITS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alfalfa is generally considered to be among the highest quality forages for feeding ruminant livestock. Among the positive quality attributes of alfalfa are high protein and calcium concentrations, low cell wall concentration, and rapidly digested cell wall material. These cell wall traits contrib...

485

Optimal foraging, not biogenetic law, predicts spider orb web allometry  

NASA Astrophysics Data System (ADS)

The biogenetic law posits that the ontogeny of an organism recapitulates the pattern of evolutionary changes. Morphological evidence has offered some support for, but also considerable evidence against, the hypothesis. However, biogenetic law in behavior remains underexplored. As physical manifestation of behavior, spider webs offer an interesting model for the study of ontogenetic behavioral changes. In orb-weaving spiders, web symmetry often gets distorted through ontogeny, and these changes have been interpreted to reflect the biogenetic law. Here, we test the biogenetic law hypothesis against the alternative, the optimal foraging hypothesis, by studying the allometry in Leucauge venusta orb webs. These webs range in inclination from vertical through tilted to horizontal; biogenetic law predicts that allometry relates to ontogenetic stage, whereas optimal foraging predicts that allometry relates to gravity. Specifically, pronounced asymmetry should only be seen in vertical webs under optimal foraging theory. We show that, through ontogeny, vertical webs in L. venusta become more asymmetrical in contrast to tilted and horizontal webs. Biogenetic law thus cannot explain L. venusta web allometry, but our results instead support optimization of foraging area in response to spider size.

Gregori?, Matjaž; Kiesbüy, Heine C.; Quiñones Lebrón, Shakira G.; Rozman, Alenka; Agnarsson, Ingi; Kuntner, Matjaž

2013-03-01

486

HABITAT USE BY FORAGING NORTHERN HARRIERS ON NANTUCKET ISLAND, MASSACHUSETTS  

E-print Network

,2 CURTICE R. GRIFFIN,1 AND KEVIN MCGARIGAL1 ABSTRACT.--The Northern Harrier (Circus cyaneus) is of major reduces foraging habitat. Received 26 January 2009. Accepted 9 July 2009. Northern Harriers (Circus cyaneus) have been identified as a species of national concern by the U.S. Fish and Wildlife Service (USDI

McGarigal, Kevin

487

Diet niches of major forage fish in Lake Michigan  

USGS Publications Warehouse

A large complex of coregonine species historically dominated the fish community of Lake Michigan. The current species complex is simplified with one remaining coregonine, bloater (Coregonus hoyi), deepwater sculpin (Myoxocephalus thompsoni), slimy sculpin (Cottus cognatus), and two dominant invaders, alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax). To better understand the diet relationships of the major offshore forage fishes now in Lake Michigan, diets of bloater, alewife, rainbow smelt, deepwater sculpin, and slimy sculpin were compared. The three sites, chosen to represent northern, central, and southern components of the lake, were sampled during spring, summer, and fall in 1994, and spring and fall in 1995. Forage fishes had diverse and variable diets, with niches differentiated by prey type or location. Diporeia hoyi, Mysis relicta, and zooplankton were the major diet items. The index of relative importance showed benthic (slimy and deepwater sculpins) and pelagic (alewife, rainbow smelt) feeding strategies with opportunistic bloaters incorporating both feeding strategies. Highest diet overlaps were between species of sculpin, and between large and small bloaters; both groups partitioned food by size. Though competition for food may be minimized by spatial segregation of potential competitors, the forage fish in Lake Michigan apparently partition food resources. Fishery management models incorporating food habits of pelagic forage fish would need to take into account diet variation associated with location and season. ?? 2007 E. Schweizerbart'sche Verlagsbuchhandlung.

Davis, B.M.; Savino, J.F.; Ogilvie, L.M.

2007-01-01

488

Quest for Nutritional and Medicinal Forages for Meat Goats  

Technology Transfer Automated Retrieval System (TEKTRAN)

Appalachian meat goat producers are encountering animal nutritional and health problems for which research-based solutions are limited. Goats prefer to eat weeds and browse, selecting the highest quality herbage available. Foraging on traditional pastures not only limits the variety of plant speci...

489

Imidacloprid Alters Foraging and Decreases Bee Avoidance of Predators  

E-print Network

of neonicotinoid pesticides, which can impair honey bee cognition. We provide the first demonstration on bees [8]. However, neonicotinoids remain widely used around the world [9]. Continued researchImidacloprid Alters Foraging and Decreases Bee Avoidance of Predators Ken Tan1,2 *, Weiwen Chen2

Nieh, James

490

Foraging Ecology of Pileated Woodpeckers in Coastal Forests of Washington  

Microsoft Academic Search

In the Pacific Northwest, providing adequate habitat forpileated woodpeckers (Dryocopus pileatus) has been a key component Of federal forest management strategies for over 20 years. Although their nesting and roosting ecology has been well studied, information on their foraging ecology is limited. From 1990 to 1995, we studied food habits of pileated woodpeckers in coastal forests (with scat analysis); estimated

CATHERINE M. RALEY; KEITH B. AUBRY

2006-01-01

491

Estimating Forage Quality of Grazing Ruminants (Part 2)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Meeting the nutritional needs of a mother cow through the different physiological stages of reproduction, lactation and recovery from parturition is very important to sustained productivity. Having a calf and nursing it to weaning every year is quite a task. Consuming sufficient high quality forag...

492

FLOCKING AND FORAGING BEHAVIOR OF WINTERING PROTHONOTARY WARBLERS  

Microsoft Academic Search

We quantified flocking behavior and examined the impact of social context (solitary, single- species flocks, and mixed-species flocks) on the foraging behavior of Prothonotary Warblers ( Protonotaria citrea) wintering in a Costa Rican mangrove forest and surrounding habitats. Based on observations collected over two winters during 70 visits to four sites, 87% (483) of the 555 Prothonotary Warblers encountered moved

Ian G. Warkentin; Eugene S. Morton

2000-01-01

493

Analyses of Two Parasitoids with Convergent Foraging Strategies  

Microsoft Academic Search

We compared the foraging strategies of two key braconid endoparasitoids of the tobacco budworm (Heliothis virescens Fab.), Cardiochiles nigriceps Vier. and Microplitis croceipes Cresson, that differ in host and habitat range but otherwise share comparable, overlapping niches. The most important host-location cues by far for both species were materials associated with damaged plants. Both species demonstrated a significant preference for

Consuelo M. De Moraes; W. J. Lewis

1999-01-01

494

AGE AND FORAGING ABILITY RELATIONSHIPS OF OLIVACEOUS CORMORANTS  

Microsoft Academic Search

The gradual development of food capturing abilities by young birds has been documented in several species that exhibit marked differences in forag- ing methods and sites. The young of Brown Pelicans (Pelecanus occidentalis; Orians 1969)) Little Blue Herons (Florida caerulea; Recher and Recher 1969)) Sandwich Terns (Sterna sanduicensis; Dunn 1972)) and Adelie Penguins (Pygoscelis adeliae; Ainley and Schlatter 1972) all

MICHAEL L. MORRISON; R. DOUGLAS SLACK; EDWIN SHANLEY

1978-01-01

495

FORAGING SITE SELECTION BY NONBREEDING WHITE-FACED IBIS  

Microsoft Academic Search

We examined foraging site selection by White-faced Ibis (Plegadis chihi) wintering in the Grasslands Ecological Area, which contains the second largest population of nonbreeding ibis in California. We compared habitat variables at White-faced Ibis for- aging sites with paired, random locations in managed wetlands of the Grasslands. We contrasted the density and biomass of benthic macroinvertebrates between a subsample of

Rebecca J. Safran; Mark A. Colwell; Craig R. Isola; Oriane E. Taft

2000-01-01

496

Estimating Shrub Forage Yield and Utilization Using a Photographic Technique  

Microsoft Academic Search

We assessed a photographic technique to estimate shrub yield and utilization of common snowberry (Symphoricarpos albus (L.) Blake), snowbrush (Ceanothus velutinus Douglas ex Hook.), and firmleaf willow ( Salix rigida Muhl.) found in mixed-conifer rangelands. We determined the correlation between green leaf area size (LA) and forage yield (Y) and compared plant utilization estimated by photographic technique (ULA) to actual

Daalkhaijav Damiran; Timothy DelCurto; Douglas E. Johnson; Scott L. Findholt; Bruce K. Johnson

2006-01-01

497

Fact Sheet: Accurately measuring forage yield in pastures  

Technology Transfer Automated Retrieval System (TEKTRAN)

Farmers have a few options for measuring pasture yield. These include pasture rulers, plate meters, and electronic gauges. Pasture rulers simply measure canopy height and assume that forage yield is directly related to height. Plate meters improve accuracy by measuring compressed height. Electronic ...

498

Forage quality of red clover intercropped in winter cereal grains  

Technology Transfer Automated Retrieval System (TEKTRAN)

Incorporating winter cereal grains into North Central U.S. corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotations requires recommendations for optimizing cropping systems. The addition of a red clover (Trifolium pratense L.) intercrop to winter cereal grains can provide forage; however, the ...

499

Utilization of Pasture and Forages by Ruminants: A Historical Perspective  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pastures, forages and grasslands dominate the landscape across the United States and support a large ruminant population that supplies the nation with value-added animal products. An historical perspective is presented of the innovations as they occurred in the Journal of Animal Science over the pas...

500

The Self-Construction and -Repair of a Foraging  

E-print Network

The Self-Construction and -Repair of a Foraging Organism by Explicitly Specified Development from¨rich, Switzerland rjd@ini.phys.ethz.ch Keywords Self-construction, self-repair, behaving organism, stigmergy need for novel engineering methods that offer self-construction, adaptation to the environment

Siegelmann , Hava T