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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

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

10

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

11

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

12

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

13

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

14

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

15

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

16

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

E-print Network

associée au CNRS n! 230 40, Avenue du Recteur Pineau 86022 Poitiers Cédex, France. Summary. The pineal. In order to elucidate the sensory function of the pineal organ of the pike, Esox lucius, the acetylcholinesterase (AChE) reaction of Karnovsky and Roots (1964) was used to demonstrate the pineal neurons. Thirty

Paris-Sud XI, Université de

17

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

E-print Network

du Recteur-Pineau, 86022 Poitiers Cedex, France. Summary. The pineal organ of the pike (Esox lucius L and pharmacological study The pineal organ of the pike was studied in natural conditions in autumn and winter (short fluorophores varied quantitatively, depending on the pineal region and the light-dark cycle. The distal part

Paris-Sud XI, Université de

18

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

E-print Network

Pineau, 86022 Poitiers Cedex, France. Summary. The pineal organ of the pike, Esox lucius L., I. A light and electron microscopic study. This report presents a study of the pineal organ of pike using light and electron micros- copy. Light microscopy showed a clear regional differentiation. The pineal end

Boyer, Edmond

19

Chemical labeling of northern pike ( Esox lucius ) by the alarm pheromone of fathead minnows ( Pimephales promelas )  

Microsoft Academic Search

In previous experiments, chemical stimuli from northern pike (Esox lucius) elicited fright responses from pike-naive fathead minnows (Pimephales promelas) only if the pike had recently eaten conspecific minnows. We used a behavioral assay to determine if the fright response is the result of the incorporation of the minnow alarm pheromone into the chemical signature of the pike. Because the alarm

Alicia Mathis; R. Jan F. Smith

1993-01-01

20

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

21

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

22

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

23

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

24

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

25

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

26

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

27

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

28

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

29

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

30

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

31

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

32

The inf luence of the invasive black bullhead Ameiurus melas on the predatory efficiency of pike Esox lucius L  

Microsoft Academic Search

The influence of the invasive black bullhead Ameiurus melas on the predatory efficiency of the pike Esox lucius was investigated using an additive experimental design. Pike predatory success on 0þ years roach Rutilus rutilus was significantly reduced in the presence of black bullhead. Among the different hypotheses that may explain such a pattern, the hypothesis of direct competition between pike

K. KREUTZENBERGER; F. L EPRIEUR; S. BROSSE

2008-01-01

33

The conservation and fishery benefits of protecting large pike (Esox lucius L.) by harvest regulations in recreational fishing  

E-print Network

The conservation and fishery benefits of protecting large pike (Esox lucius L.) by harvest regulations in recreational fishing Robert Arlinghaus a,b,*, Shuichi Matsumura a,c,1 , Ulf Dieckmann c a Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries

Dieckmann, Ulf

34

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

35

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

E-print Network

Poitiers Cedex, France. Summary. The pineal organ of the pike (Esox lucius, L.). V. Radioautographic study investigation is to characterize the sites of indole meta- bolism in the pike pineal organ using, the pineal organs were incubated for 10 to 20 min in four dif- ferent physiological media containing 3H-5-HTP

Paris-Sud XI, Université de

36

ENDOCRINE (SEXUAL) DISRUPTION IS NOT A PROMINENT FEATURE IN THE PIKE (ESOX LUCIUS), A TOP PREDATOR, LIVING IN ENGLISH WATERS  

Microsoft Academic Search

The high incidence of intersex roach ( Rutilus rutilus) in some United Kingdom rivers that has been associated with exposure to sewage treatment works (STWs) effluent led us to hypothesize that top predator fish also may be affected by estrogenic chemicals, because they are likely to bioaccumulate lipophilic compounds through a predator-prey relationship. To investigate this possibility, pike (Esox lucius)

Emma Vine; Jan Shears; Ronny van Aerle; Charles R. Tyler; John P. Sumpter

2005-01-01

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

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

PubMed

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. PMID:24667854

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

2014-08-01

39

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

40

Altered energetics and parasitism in juvenile northern pike (Esox lucius) inhabiting metal-mining contaminated lakes.  

PubMed

The objective of this study was to evaluate possible factors that could be contributing to altered bioenergetics of juvenile northern pike (Esox lucius) living in lakes receiving effluent from the Key Lake uranium mill in northern Saskatchewan, Canada. Although glycogen and triglycerides stores in liver and muscle were significantly greater in pike from exposure lakes compared to the reference, triglycerides stores of aquatic insects and spottail shiners that are prey items of juvenile pike showed no overall differences among lakes. Measures of parasitism, on the other hand, were negatively correlated with pike bioenergetics thereby reflecting a possible energetic cost of parasitism on reference lake fishes. The degree of infection, as measured by the abundance and biomass of intestinal parasites and the abundance of monogeneans on pike gills, was greatest in reference fishes and intermediate in low-exposure pike, whereas high-exposure fishes harbored no parasites. PMID:18329711

Kelly, Jocelyn M; Janz, David M

2008-07-01

41

'Soft' harness for external attachment of large radio transmitters to northern pike (Esox lucius)  

USGS Publications Warehouse

We developed a 'soft' harness for dorsally attaching large, external radio transmitters to northern pike (Esox lucius). The key harness component was a soft, flexible, thick-walled tubing that prevented tissue abrasion by the attachment lines which passed through the tubing. Six field-tagged fish (1.5-7.5 kg) were monitored for 45-115 days before tracking was terminated. Tracking patterns of fish indicated no apparent effect of these large, external transmitters on movement behavior; further, the transmitters did not appear to entangle the fish in vegetation. One fish with its transmitter still secure was recaptured after 54 days, and there was minimal tissue erosion under the transmitter. With minor improvements for the attachment lines and the transmitter saddle, the method is suitable for externally attaching large telemetry transmitters to fish.

Herke, S.W.; Moring, J.R.

1999-01-01

42

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

43

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

44

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

45

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

46

Age and growth of pike (Esox lucius) in Chivyrkui Bay, Lake Baikal  

USGS Publications Warehouse

The purpose of this study was to describe age and growth of pike (Esox lucius) in Lake Baikal. Pike were collected with gill nets and by angling in Chivyrkui Bay in late July-early August 1993 and by gill nets in June 1995. Total length (mm), weight (g), and sex were recorded and scales and cleithra were collected for aging. In 1993, pike, ages 1 to 3, ranged in length from 331 to 810 mm and in 1995 , pike, ages 2 to 10, ranged in length from 365 to 1,111 mm but only three percent were age 7 or older. Most growth in length occurred during the first two years of life. The length-weight relation for pike from Chivyrkui Bay was similar to that of pike from the St. Lawrence River. Calculated total length of pike from Lake Baikal equalled or exceeded the lengths of pike from lakes Erie or Ontario. Good agreement was found between ages from cleithra and from scales. Lengths at age in June 1995 (N=108) varied widely among pike. Females were generally larger than males at a given age among fish age-3 and older. When compared with the circumpolar growth standard, based on the von Bertalanffy growth curve, growth of Lake Baikal pike exceeded all other Asian populations, and equalled or exceeded many other northern hemisphere populations.

Owens, Randall W.; Pronin, Nikolai M.

2000-01-01

47

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

48

Genetic structure of pike (Esox lucius) reveals a complex and previously unrecognized colonization history of Ireland  

PubMed Central

Aim We investigated genetic variation of Irish pike populations and their relationship with European outgroups, in order to elucidate the origin of this species to the island, which is largely assumed to have occurred as a human-mediated introduction over the past few hundred years. We aimed thereby to provide new insights into population structure to improve fisheries and biodiversity management in Irish freshwaters. Location Ireland, Britain and continental Europe. Methods A total of 752 pike (Esox lucius) were sampled from 15 locations around Ireland, and 9 continental European sites, and genotyped at six polymorphic microsatellite loci. Patterns and mechanisms of population genetic structure were assessed through a diverse array of methods, including Bayesian clustering, hierarchical analysis of molecular variance, and approximate Bayesian computation. Results Varying levels of genetic diversity and a high degree of population genetic differentiation were detected. Clear substructure within Ireland was identified, with two main groups being evident. One of the Irish populations showed high similarity with British populations. The other, more widespread, Irish strain did not group with any European population examined. Approximate Bayesian computation suggested that this widespread Irish strain is older, and may have colonized Ireland independently of humans. Main conclusions Population genetic substructure in Irish pike is high and comparable to the levels observed elsewhere in Europe. A comparison of evolutionary scenarios upholds the possibility that pike may have colonized Ireland in two ‘waves’, the first of which, being independent of human colonization, would represent the first evidence for natural colonization of a non-anadromous freshwater fish to the island of Ireland. Although further investigations using comprehensive genomic techniques will be necessary to confirm this, the present results warrant a reappraisal of current management strategies for this species. PMID:25435649

Pedreschi, Debbi; Kelly-Quinn, Mary; Caffrey, Joe; O’Grady, Martin; Mariani, Stefano; Phillimore, Albert

2014-01-01

49

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

50

Biomarkers of contaminant exposure in northern pike (Esox lucius) from the Yukon River Basin, Alaska  

USGS Publications Warehouse

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 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/mm2), size (812 to 1481 ??m2), 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 (???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. ?? 2007 Springer Science+Business Media, LLC.

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

2007-01-01

51

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

52

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

53

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

54

Use of Carbopol resin for carp pituitary administration improves the fertilization percentage of northern pike ( Esox lucius Linnaeus) eggs in commercial hatcheries  

Microsoft Academic Search

The efficiency of northern pike (Esox lucius Linnaeus) fry production via hormonal treatment of wintered broodstock is, in general, relatively low due to low egg fertilization\\u000a percentage. It has been experimentally demonstrated that administration of acetone-dried carp pituitary extract in a slow-release\\u000a vehicle of aqueous dispersion of Carbopol 971 P resin (CP) resulted in a higher mean fertilization percentage, possibly

Tamás Szabó

2008-01-01

55

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

56

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

57

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

58

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

59

Quantifying selection differentials caused by recreational fishing: development of modeling framework and application to reproductive investment in pike (Esox lucius).  

PubMed

Methods for quantifying selection pressures on adaptive traits affected by size-selective fishing are still scarce, and none have as yet been developed for recreational fishing. We present an ecologically realistic age-structured model specifically tailored to recreational fishing that allows estimating selection differentials on adaptive life-history traits. The model accounts for multiple ecological feedbacks, which result in density-dependent and frequency-dependent selection. We study selection differentials on annual reproductive investment under size-selective exploitation in a highly demanded freshwater recreational fish species, northern pike (Esox lucius L.). We find that recreational angling mortality exerts positive selection differentials on annual reproductive investment, in agreement with predictions from life-history theory. The strength of selection increases with the intensity of harvesting. We also find that selection on reproductive investment can be reduced by implementing simple harvest regulations such as minimum-size limits. The general, yet computationally simple, methods introduced here allow evaluating and comparing selection pressures on adaptive traits in other fish populations and species, and thus have the potential to become a tool for evolutionary impact assessment of harvesting. PMID:25567885

Arlinghaus, Robert; Matsumura, Shuichi; Dieckmann, Ulf

2009-08-01

60

Quantifying selection differentials caused by recreational fishing: development of modeling framework and application to reproductive investment in pike (Esox lucius)  

PubMed Central

Methods for quantifying selection pressures on adaptive traits affected by size-selective fishing are still scarce, and none have as yet been developed for recreational fishing. We present an ecologically realistic age-structured model specifically tailored to recreational fishing that allows estimating selection differentials on adaptive life-history traits. The model accounts for multiple ecological feedbacks, which result in density-dependent and frequency-dependent selection. We study selection differentials on annual reproductive investment under size-selective exploitation in a highly demanded freshwater recreational fish species, northern pike (Esox lucius L.). We find that recreational angling mortality exerts positive selection differentials on annual reproductive investment, in agreement with predictions from life-history theory. The strength of selection increases with the intensity of harvesting. We also find that selection on reproductive investment can be reduced by implementing simple harvest regulations such as minimum-size limits. The general, yet computationally simple, methods introduced here allow evaluating and comparing selection pressures on adaptive traits in other fish populations and species, and thus have the potential to become a tool for evolutionary impact assessment of harvesting. PMID:25567885

Arlinghaus, Robert; Matsumura, Shuichi; Dieckmann, Ulf

2009-01-01

61

{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

62

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

63

Determination of polychlorinated biphenyls and total mercury in two fish species (Esox lucius and Carassius auratus) in Anzali Wetland, Iran.  

PubMed

The Anzali Wetland is one of the most important ecosystems in the north of Iran, and parts of it were registered as a Ramsar site in 1975. However, even though, due to many problems, including eutrophication produced by inflow of excess nutrients and organic materials, the wetland was also listed on the Montreux Record indicating the need to take urgent remedial action. This study was conducted to study the levels of polychlorinated biphenyls (PCBs) and total mercury (THg) in two fish species (Esox lucius and Carassius auratus) as bio-indicators of the ecosystem condition in eastern part of Anzali Wetland. The sampling was carried out in six different periods between years 2009 and 2010. The results showed that the amounts of PCBs in the muscle of northern pike were below the detection limit of gas chromatography, whereas the average concentration in goldfish was 0.449 mg/kg wet weight. Some possible reasons for the higher levels of PCBs in goldfish in comparison with pike have been discussed. No significant (p?

Sakizadeh, Mohammad; Esmaeili Sari, Abas; Abdoli, Asghar; Bahramifar, Nader; Hashemi, Seyed Hossein

2012-05-01

64

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. PMID:25614787

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

2014-01-01

65

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

PubMed

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 (F ST = 0.0208) but spatially variable with mean level of differentiation in the upstream section of the studied area being threefold higher (F ST = 0.0297) than observed in the downstream sector (F ST = 0.0100). Beside interannual water level fluctuation, 19 additional variables were considered and a multiple regression on distance matrices model (R (2)  = 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. PMID:25614787

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

2014-10-01

66

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

67

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

68

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

69

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

70

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

71

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

72

Metabolic enzymes activity and histomorphology in the liver of whitefish (Coregonus lavaretus L.) and pike (Esox lucius L.) inhabiting a mineral contaminated lake.  

PubMed

The effects of wastewater from a mining and ore-dressing mill on fish in Lake Kostomukshskoe, which is used as a cesspool of circulating water and for storage of industrial wastes produced by the Kostomuksha mining and ore-dressing mill in northwest Russia, were studied. The lake is characterized by heavy mineralization, high pH, elevated levels of K(+), Li(+), SO4 (2-), NO(2-), Cl(-), Li, Mn, and Ni, and the presence of a fine-dispersed mechanical suspension. To assess the impact of contamination on fish and determine the mechanisms of their adaptation, we investigated the biochemical indices and histology of the liver of whitefish (Coregonus lavaretus L.) and pike (Esox lucius L.) inhabiting Lake Kostomukshskoe, downstream Lake Koyvas (64° 47' 30° 59'), and Lake Kamennoe, which is located in a nature preserve and has not been affected by anthropogenic activity (64° 28' 30° 13'). Changes were detected in the activity of metabolic enzymes (cytochrome c oxidase (COX), lactate dehydrogenase, and glucose-6-phosphate dehydrogenase) in the liver. Specifically, the COX activity in the liver of both fish species from the contaminated lake decreased, indicating a low level of aerobic metabolism. Lipid infiltration was the most visible and widespread change observed in the liver of both fish species; therefore, it can be considered a marker of such long-term contamination. Lesions in pike liver demonstrated a wider range of severity than in those of whitefish. In summary, metabolic enzyme activity and histomorphology of the liver of whitefish and pike differed among lakes in a species-specific manner. The changes in enzyme activity and histomorphological alterations in fish that were observed can be applied for evaluation of freshwater systems that may be subjected to mineral pollution. PMID:24865502

Churova, Maria V; Murzina, Svetlana A; Meshcheryakova, Olga V; Nemova, Nina N

2014-12-01

73

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

74

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

2015-04-01

75

Diplostomatid Eye Flukes in Young-of-the-Year and Forage Fishes in the St. Lawrence River, Quebec  

Microsoft Academic Search

Sixteen species of young-of-the year and forage fishes (alewife Alosa pseudoharengus, northern pike Esox lucius, common carp Cyprinus carpio, emerald shiner Notropis atherinoides, rosyface shiner Notropis rubellus, white sucker Catostomus commersoni, silver redhorse Moxostoma anisurum, brown bullhead Ameirurus nebulosus, trout-perch Percopsis omiscomaycus, rock bass Ambloplitis rupestris, pumpkinseed Lepomis gibbosus, smallmouth bass Micropterus dolomieu, largemouth bass Micropterus salmoides, black crappie Pomoxis

David J. Marcogliese; Sacha Compagna

1999-01-01

76

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

77

Molecular and Phenotypic Evidence of a New Species of Genus Esox (Esocidae, Esociformes, Actinopterygii): The Southern Pike, Esox flaviae  

PubMed Central

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

78

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

79

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

80

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

81

Esox lucius k = (y2 -y1) / (x2 -x1)  

E-print Network

"SLU develops the understanding and sustainable use and management of biological natural resources of Forest Sciences The Faculty of Natural Resources and Agricultural Sciences The Faculty of Veterinary, Sweden's capital city, and took over the training of veterinary students from Skara. The institute

82

Seasonal dynamics of fatty acid composition in female northern pike ( Esox lucius L.)  

Microsoft Academic Search

Seasonal changes in the fatty acid composition of neutral and polar lipids were measured in the ovary, liver, white muscle, and adipopancreatic tissue of northern pike. The role of environmental and physiological factors underlying these changes was evaluated. From late summer (August–September) to winter (January–March), the weight percentage of n-3 polyunsaturated fatty acids (especially 22:6n3) declined significantly in the neutral

K. Schwalme; W. C. Mackay; M. T. Clandinin

1993-01-01

83

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

84

Precocious induction of maturation and ovulation in northern pike (Esox lucius)  

E-print Network

PPSG/kg gave satisfactory ovulation (89 p. 100) and fertilization (83 p. 100) rates ; a minimum dose or no ovulation. In all the above cases using the combined treatment or 17a-20p P alone, fertilization rates were and ovulation in pike. Since another salmon gonadotropic preparation (SG-G100) was found active on in vitro

Paris-Sud XI, Université de

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

UV-B exposure causes DNA damage and changes in protein expression in northern pike (Esox lucius) posthatched embryos.  

PubMed

The ongoing anthropogenically caused ozone depletion and climate change has increased the amount of biologically harmful UV-B radiation, which is detrimental to fish in embryonal stages. The effects of UV-B radiation on the levels and locations of DNA damage manifested as cyclobutane pyrimidine dimers (CPDs), heat shock protein 70 (HSP70) and p53 protein in newly hatched embryos of pike were examined. Pike larvae were exposed in the laboratory to current and enhanced doses of UV-B radiation. UV-B exposure caused the formation of CPDs in a fluence rate-dependent manner, and the CPDs were found deeper in the tissues with increasing fluence rates. UV-B radiation induced HSP70 in epidermis, and caused plausible p53 activation in the brain and epidermis of some individuals. Also at a fluence rate occurring in nature, the DNA damage in the brain and eyes of pike and changes in protein expression were followed by severe behavioral disorders, suggesting that neural molecular changes were associated with functional consequences. PMID:22145705

Vehniäinen, Eeva-Riikka; Vähäkangas, Kirsi; Oikari, Aimo

2012-01-01

87

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

88

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

89

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

90

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

91

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

92

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

93

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

94

L'organe pinal du Brochet (Esox lucius, L.) II. Etude en microscopie lectronique de la diffrenciation  

E-print Network

associé au CNRS n° 290, 40, Avenue du Recteur Pineau, 86022 Poitiers Cedex, France. Summary. The pineal differentiation and regression and variations of the photoreceptive potential in different pineal regions. Photoreceptor cells (P) of the pike pineal organ were examined by electron microscopy. They showed the usual

Boyer, Edmond

95

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

96

Prey capture in the chain pickerel, Esox niger: correlations between feeding and locomotor behavior  

E-print Network

Prey capture in the chain pickerel, Esox niger: correlations between feeding and locomotor behavior in the chain pickerel, Esox niger: correlations between feeding and locomotor behavior. Can. J. Zool. 59: 1072-1078. The predatory behavior of the chain pickerel Esox niger was studiedby high-speed cinematography to correlate

Lauder, George V.

97

OCCURRENCE OF 'ESOX NIGER' IN SANTA ROSA SOUND, FLORIDA  

EPA Science Inventory

This is the first report of Esox niger collected from the normally saline portion of the lower Pensacola estuary. A 109 mm standard length chain pickerel was seined on 7 August 1975 from Santa Rosa Sound, in Santa Rosa County, Florida, from Thalassia beds about 300 m W. of the N....

98

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

99

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...

100

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 lucius, rock bass Ambloplites rupestris, smallmouth bass Micropterus dolomieu, and walleye Sander vitreus

Ricciardi, Anthony

101

U.S. Department of the Interior U.S. Geological Survey  

E-print Network

(APHIS, 2006). Species affected by the APHIS rule included muskellunge, northern pike, Esox lucius isolated from 25 fish species (for example, muskellunge, Esox masuqinongy, and freshwater drum, Aplodinotus

Torgersen, Christian

102

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

103

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

104

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

105

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

106

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

107

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

108

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

109

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

110

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

111

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

112

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.  

PubMed

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 delta15N, 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 and PBDEs. All investigated PCBs (tri- to deca-CBs) biomagnify and the biomagnification potential is positively correlated with hydrophobicity up to log Kow 8.18. Tri- to hepta-BDEs also biomagnify but showed a maximum biomagnification for the penta-BDEs (log Kow 6.46-6.97). The biomagnification of hexa- to hepta-PBDEs was negatively correlated with degree of bromination, likely due to large molecular size or high molecular weight (644-959 Da). Octa-, nona- and deca-BDEs did not biomagnify but were found in two (octa-BDE) and three (nona- and deca-BDEs) of the species, respectively. Increased size of pike is correlated with increased lipid weight based PCB and PBDE concentrations in males but not in females and mean PCB and PBDE concentrations in males are generally higher than in females. For the least hydrophobic PCBs, no sex difference is observed, probably as a consequence of faster clearance of these substances over the gills, making the spawning clearance of PCBs and PBDEs of lesser relative importance. PMID:15051373

Burreau, Sven; Zebühr, Yngve; Broman, Dag; Ishaq, Rasha

2004-05-01

113

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

114

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

115

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

116

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

117

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

118

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

119

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.

120

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

121

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

122

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...

123

Forage Storage Systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forages are a major component of the diet for cattle and other livestock. In most parts of the world, forage production is seasonal so that some forage must be harvested by the farmer and stored. The two main systems for storing forage are as hay and silage. With hay, the forage is dried to approxim...

124

United States Department of the Interior, Fred A. Seaton, Secretary  

E-print Network

) . In North America the~e are five specie s: Esox masquinongy (muskellunge) , Esox lucius (northern #12;pike confused as pike and pickerel. The true pikes a ll belong to one fam- ily (Esocidae) and to one genus (Esox, pike, pickerel, jack), Esox niger (chain or eastern picker el) ) Esox vermiculatus (grass, mud

125

United States Department of the Interior, Douglas McKay, Secretary Fish and Wildlife Service, John L. Farley, Director  

E-print Network

). In North America there are five species: Esox masquinongy (muskellunge), Esox lucius (north- ern pike, pike confused as pike and pickerel. The true pikes all belong to one family (Esocidae) and to one genus (Esox, pickerel, jack), Esox nig)r (chain-or-eastern pickerel), Esox vermiculatus (mUd or little pickerel

126

Heat Damaged Forages: Effects on Forage Quality  

Technology Transfer Automated Retrieval System (TEKTRAN)

Traditionally, heat damage in forages has been associated with alterations in forage protein quality as a result of Maillard reactions, and most producers and nutritionists are familiar with this concept. However, this is not necessarily the most important negative consequence of spontaneous heating...

127

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

128

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

129

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

130

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

131

Defining Forage Quality  

E-print Network

&M University Research and Extension Cen- ter, respectively, The Texas A&M University System. L-5481 01/07 Yoana C. Newman, Barry Lambert and James P. Muir* #24; animal production of forage-based diets depends on the nutritive value of forage consumed...

Muir, James; Lambert, Barry; Newman, Yoana

2007-01-18

132

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

133

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, ...

134

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

135

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

136

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

137

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

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

INTERNATIONAL PROSPECTUS 20152016 STUDY AT SLU  

E-print Network

is at your fingertips. Lisa Sennerby-Forsse Vice-Chancellor, SLU #12;3 Esox lucius (x - x1)² + (y - yEsox lucius (x - x1)² + (y - y CONTENT 2 WELCOME TO SLU AND SWEDEN! 4 SLU in brief 6 Why study in Sweden? 8

140

Do You Have Enough Forage?  

E-print Network

To limit the impact of a forage crisis, a rancher must be able to recognize forage shortfalls and make timely decisions for the good of the livestock and the enterprise. This publication discusses strategies that help ranchers determine exactly how...

White, Larry D.

1999-02-12

141

FORAGE QUALITY AND THE ENVIRONMENT  

Microsoft Academic Search

The influence of environmental factors on forage quality of temperate and tropical grasses has been reviewed by several authors, who summarized how light, temperature, drought and soil nutrients influence chemical composition, and digestibility of forages grown in contrasting areas of the world. The effects of season of the year on forage growth, grazing behavior and animal performance have also been

C. E. Lascano; A. Schmidt; R. Barahona

142

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

143

Muskie lunacy: does the lunar cycle influence angler catch of muskellunge (Esox masquinongy)?  

USGS Publications Warehouse

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.

Vinson, Mark R.; Angradi, Ted R.

2014-01-01

144

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

145

Muskie Lunacy: does the lunar cycle influence angler catch of muskellunge (Esox masquinongy)?  

PubMed

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

146

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

147

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

148

Wide home ranges for widely foraging lizards  

Microsoft Academic Search

Space usage by animals may be influenced by a range of factors. In this study we investigate whether foraging behaviour affects the home range size of lizards. Two distinct tactics of foraging have been recognized in predators: sit-and-wait foraging (SW) and active foraging (AF). Foraging activity level of a data set of lizard species, mainly compiled from literature, is compared

Dave Verwaijen; Raoul Van Damme

2008-01-01

149

2010 Forage Variety Yield2010 Forage Variety Yield SummarySummary  

E-print Network

2010 Forage Variety Yield2010 Forage Variety Yield SummarySummary Cornell University J. Hansen, 1 E C T I O N #12;2010 Forage Variety Yield Summary Cornell University Dept. of Plant Tool www.forages.org/ Forage yield trial results for NY Cornell Published results of forage trials http

Pawlowski, Wojtek

150

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

151

ORIGINAL PAPER Evolutionary Foraging Models in Zooarchaeological  

E-print Network

ORIGINAL PAPER Evolutionary Foraging Models in Zooarchaeological Analysis: Recent Applications these models build on conventional ideas about utility firmly embedded in zooarchaeological analyses, when cast of current zooarchaeological applications of foraging models. Recent applications of foraging models

Kohler, Tim A.

152

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

Maxwell, Bruce D.

153

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

154

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-...

155

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:...

156

NONSTRUCTURAL CARBOHYDRATES IN OAT FORAGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nonstructural carbohydrates (NSC) fractions found in forage may play a role in equine diseases that involve carbohydrate intolerance, such as laminitis. Sugars in forage may adversely affect equines with dysfunctions of glucose metabolism. Insulin resistance has been associated with laminitis in e...

157

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

158

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

159

Root Foraging Influences Plant Growth Responses to Earthworm Foraging  

PubMed Central

Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L.) impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants. PMID:25268503

Cameron, Erin K.; Cahill, James F.; Bayne, Erin M.

2014-01-01

160

Root foraging influences plant growth responses to earthworm foraging.  

PubMed

Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L.) impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants. PMID:25268503

Cameron, Erin K; Cahill, James F; Bayne, Erin M

2014-01-01

161

NORTHEAST FLORIDA BEEF & FORAGE GROUP  

E-print Network

-2402, CBSanders@ifas.ufl.edu http://alachua.ifas.ufl.edu/ Baker County Mike Sweat County Extension Director 352-495-2248, 352-317-1979 Forage Establishment / Sprigging Brown & Brown Farms 13992 North US 301

Watson, Craig A.

162

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.

163

Octopamine influences honey bee foraging preference  

PubMed Central

Colony condition and differences in individual preferences influence forage type collected by bees. Physiological bases for the changing preferences of individual foragers are just beginning to be examined. Recently, for honey bees octopamine is shown to influence age at onset of foraging and probability of dance for rewards. However, octopamine has not been causally linked with foraging preference in the field. We tested the hypothesis that changes in octopamine may alter forage type (preference hypothesis). We treated identified foragers orally with octopamine or its immediate precursor, tyramine, or sucrose syrup (control). Octopamine treated foragers switched type of material collected, control bees did not. Tyramine group results were not different from the control group. In addition, sugar concentrations of nectar collected by foragers after octopamine treatment were lower than before treatment, indicating change in preference. In contrast, before and after nectar concentrations for bees in the control group were similar. These results, taken together, support the preference hypothesis. PMID:17574568

Giray, Tugrul; Galindo, Alberto; Oskay, Devrim

2010-01-01

164

Fish predation selects for reduced foraging activity  

Microsoft Academic Search

Despite the importance of foraging activity for the growth\\/predation risk trade-off, studies that demonstrated predator-induced\\u000a survival selection on foraging activity under semi-natural conditions are relatively rare. Here, we tested for fish-induced\\u000a selection for reduced foraging activity in two larval Enallagma damselflies using a field enclosure experiment. Fish imposed considerable mortality in both damselfly species and survival\\u000a selection on foraging activity

Francis Strobbe; Mark A. McPeek; Marjan De Block; Robby Stoks

2011-01-01

165

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

166

Forage characteristics affecting meat goat preferences for forage chicory cultivars  

Technology Transfer Automated Retrieval System (TEKTRAN)

Concentration of bitter sesquiterpene lactones (SL), lactucin, lactucopicrin, and 8-deoxylactucin, has been associated with low soil phosphorus fertility and reduced livestock preference for forage chicory (Cichorium intybus L.). We evaluated the effect of cultivar and available soil P (ASP) on mea...

167

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

168

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

169

COOK, A. F., N. E. STACEY, AND R. E. PETER. 1980. Periovulatory changes in serum cortisol levels in  

E-print Network

in the goldfish, Carassius auratus. Gen. Compo Endocri- no\\. 40:507-510. HIROSE, K. 1976. Endocrine control pike(Esox lucius), and goldfish (Carassius auratus). J. Fish. Res. Board Can. 33:974-988. KAYA, C. M

170

LES CELLULES DE SERTOLI DES POISSONS TLOSTENS  

E-print Network

Salvelinus fontinalis HENDERSON (1962) qualifie également les cellules de la paroi des lobules de « lobules'espace extralobulaire). Il s'agit de : Esox lucius, Salvelinus willughbü et Labeo (MARSH!,r, et LOFTS, ig56 ; LOFTS et

Paris-Sud XI, Université de

171

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...

172

ANNUAL FORAGE PRODUCTION IN DROUGHT  

Microsoft Academic Search

Annual forages are widely grown in the U.S. during periods of drought. Many different crop choices are available in the inland Pacific Northwest, however they vary depending on latitude, elevation and specific climatic events during the season they are grown. For most low elevation valleys in southern Idaho and the Yellowstone and Bighorn valleys in southern Montana, warm-season dryland crops

S. Dennis Cash; Lisa M. M. Surber; David M. Wichman

173

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 ...

174

Irrigation Systems for Forage Crops.  

E-print Network

TDDe Z TA24S.7 8873 NO.1611 1?1611 ' Texas Agricultural Extension Service l'BRARY FEB 0 1 1989 texas A&M University Irrigation Systems for Forage Crops Texas Agricultural Extension Service ? Zerle L. Carpenter, Director ? The Texas A...

Henggeler, Joseph C.

1988-01-01

175

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

176

Behavior of fish predators and their prey: habitat choice between open water and dense vegetation  

USGS Publications Warehouse

Behavior of largemouth bass, Micropterus salmoides , and northern pike, Esox lucius, foraging on fathead minnows, Pimephales promelas, or bluegills, Lepomis macrochirus, was quantified in pools with 50% cover (half the pool had artificial stems at a density of 1000 stems n-2). Both predators spent most of their time in the vegetation. Largemouth bass searched for bluegills and ambushed minnows, whereas the relatively immobile northern pike ambushed all prey. Minnows were closer to predators and were captured more frequently than bluegills. Even when minnows dispersed, they moved continually and eventually wandered within striking distance of a predator. Bluegills dispersed in the cover with predators. Bass captured the few bluegills that strayed into the open and pike captured those that approached too closely in the cover. The ability of predators to capture prey while residing in habitats containing patches of dense cover may explain their residence in areas often considered to be poor ones for foraging.

Savino, Jacqueline F.; Stein, Roy A.

1989-01-01

177

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

178

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...

179

Why Range Forage Quality Changes  

E-print Network

crude protein (nucleic acids, amino acids, proteins, other nitrogen- containing compounds), sugars, starch, and lipids (fats). In compar- ison, the cell wall con- tains slowly digestible material called f_iber which includes hemi- cellulose, cellulose..., and the mostly indigestible substance lignin. These f_iber fractions are included in the neutral detergent f_iber (NDF) and acid detergent f_iber (ADF) frac- tions often used in forage analysis reports. Hemicellulose, cellulose, and lignin are included in NDF...

Lyons, Robert K.; Machen, Richard V.; Forbes, T. D. A.

1999-02-15

180

Optimal foraging in semantic memory.  

PubMed

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 structure of the search problems-searching in patchy environments-and recent evidence supporting a domain-general cognitive search process. To investigate these questions directly, we asked participants to recover from memory as many animal names as they could in 3 min. Memory search was modeled over a representation of the semantic search space generated from the BEAGLE memory model of Jones and Mewhort (2007), via a search process similar to models of associative memory search (e.g., Raaijmakers & Shiffrin, 1981). We found evidence for local structure (i.e., patches) in memory search and patch depletion preceding dynamic local-to-global transitions between patches. Dynamic models also significantly outperformed nondynamic models. The timing of dynamic local-to-global transitions was consistent with optimal search policies in space, specifically the marginal value theorem (Charnov, 1976), and participants who were more consistent with this policy recalled more items. PMID:22329683

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

2012-04-01

181

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

182

Sex differences in Adélie penguin foraging strategies  

Microsoft Academic Search

Consistent sex differences in foraging trip duration, feeding locality and diet of breeding Adlie penguins (Pygoscelis adeliae) were demonstrated at two widely separated locations over several breeding seasons. Differences in foraging behaviour were\\u000a most pronounced during the guard stage of chick rearing. Female penguins made on average longer foraging trips than males,\\u000a ranged greater distances more frequently and consumed larger

Judy Clarke; Bryan Manly; Knowles Kerry; Heather Gardner; Enrica Franchi; Simonetta Corsolini; Silvano Focardi

1998-01-01

183

Foraging performance of honey bees (Apis mellifera)  

Microsoft Academic Search

Foraging behavior and life span in individual honey bees, Apis mellifera L. were examined. I investigated the genotypic effects on these important parameters using bees derived from a two-way colony-level selection program for high and low pollen hoarding behavior. I also studied the effects of juvenile hormone (JH) on foraging preferences (nectar or pollen) and on nectar foraging performance.In an

Guiyun Deng

1996-01-01

184

Efficient Multi-foraging in Swarm Robotics  

Microsoft Academic Search

In the multi-foraging task studied in this paper, a group of robots has to efficiently retrieve two different types of prey\\u000a to a nest. Robots have to decide when they leave the nest to forage and which prey to retrieve.\\u000a \\u000a The goal of this study is to identify an efficient multi-foraging behaviour, where efficiency is defined as a function of

Alexandre Campo; Marco Dorigo

2007-01-01

185

Reduction of foraging work and cooperative breeding.  

PubMed

Using simple stochastic models, we discuss how cooperative breeders, especially wasps and bees, can improve their productivity by reducing foraging work. In a harsh environment, where foraging is the main cause of mortality, such breeders achieve greater productivity by reducing their foraging effort below full capacity, and they may thrive by adopting cooperative breeding. This could prevent the population extinction of cooperative breeders under conditions where a population of lone breeders cannot be maintained. PMID:24619571

Toyoizumi, Hiroshi; Field, Jeremy

2014-06-01

186

Genetic determination of nectar foraging, pollen foraging, and nest-site scouting in honey bee colonies  

Microsoft Academic Search

Allozyme analyses of honey bee workers revealed significant differences in the intracolonial subfamily composition of groups of nectar foragers, pollen foragers, and nest-site scouts. These differences demonstrate that colony genetic structure influences the division of labor among older foraging-age bees just as it does for younger workers. The maintenance of genetic variability for the behavior of individual workers and its

Gene E. Robinson; Robert E. Page

1989-01-01

187

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 ...

188

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

189

GRAZING SCHEDULE EFFECT on FORAGE PRODUCTION and NUTRITIVE VALUE of DIVERSE FORAGE MIXTURES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sustainability of forage production in the Northeast USA depends on suitable forage species for the environment and grazing management. The use of multispecies mixtures may increase yield and sustain forage production; however, we have no information on how grazing management affects the productivit...

190

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

191

Potential of energy production from conserved forages  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forages have a potential role in meeting the demand for energy. Perennial forages are attractive for various reasons. One, both the monetary and energy cost of planting is spread over many years. Two, we already have the equipment for harvesting, storing and transporting this source of biomass. Thre...

192

Polyphenol oxidase activity in annual forage clovers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Polyphenol oxidase (PPO)-mediated phenol reactions in red clover (Trifolium pratense L.) bind forage protein and reduce proteolysis, producing beneficial effects on forage protein degradability, silage fermentation, and soil-N cycling. We evaluated PPO activity in seven previously untested annual c...

193

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...

194

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...

195

Palatability of Forage Chicory Cultivars for Goats  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sesquiterpene lactones (SL) in forage chicory (Cichorium intybus L.) may have anthelmintic activity against gastrointestinal parasites in sheep and goats, but have been implicated in poor palatability of forage. We used three levels of soil P fertilization to influence SL concentrations in three cu...

196

Benefits of perennial forages in rotations  

Technology Transfer Automated Retrieval System (TEKTRAN)

Perennial forages are grown on over 23 million ha in the US and 8 million ha in Canada. Alfalfa is the most widely grown perennial forage species in both countries, but in the US the area of alfalfa has been declining steadily for the past 50 years, while the area of soybeans and, more recently, cor...

197

Prey Processing in Central Place Foragers  

Microsoft Academic Search

The importance of prey processing as an integral part of foraging behaviour has long been acknowledged, but little theoretical consideration has been given to the optimization of the processing behaviour itself. Processing renders food down to ingestible, palatable portions, and also removes non-essential mass thus reducing transport costs. Here, several models of processing are developed for a central place forager.

SEAN A. RANDS; ALASDAIR I. HOUSTON; CATHERINE E. GASSON

2000-01-01

198

Visual perception and social foraging in birds  

Microsoft Academic Search

Birds gather information about their environment mainly through vision by scanning their surroundings. Many prevalent models of social foraging assume that foraging and scanning are mutually exclusive. Although this assumption is valid for birds with narrow visual fields, these models have also been applied to species with wide fields. In fact, available models do not make precise predictions for birds

Esteban Fernández-Juricic; Jonathan T. Erichsen; Alex Kacelnik

2004-01-01

199

Optimal Foraging by Birds: Experiments for Secondary & Postsecondary Students  

ERIC Educational Resources Information Center

Optimal foraging theory attempts to explain the foraging patterns observed in animals, including their choice of particular food items and foraging locations. We describe three experiments designed to test hypotheses about food choice and foraging habitat preference using bird feeders. These experiments can be used alone or in combination and can…

Pecor, Keith W.; Lake, Ellen C.; Wund, Matthew A.

2015-01-01

200

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

201

Information Foraging in Nuclear Power Plant Control Rooms  

Microsoft Academic Search

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

R. L. Boring

2011-01-01

202

Flexible search tactics and efficient foraging in saltatory searching animals  

Microsoft Academic Search

Foraging is one of the most important endeavors undertaken by animals, and it has been studied intensively from both mechanistic-empirical and optimal foraging perspectives. Planktivorous fish make excellent study organisms for foraging studies because they feed frequently and in a relatively simple environment. Most optimal foraging studies of planktivorous fish have focused, either on diet choice or habitat selection and

W. John O'Brien; Barbara I. Evans; Howard I. Browman

1989-01-01

203

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

204

Perennial forages as second generation bioenergy crops.  

PubMed

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 (Phalaris arundinacea L.), and alfalfa (Medicago sativa L.). An advantage of using forages as bioenergy crops is that farmers are familiar with their management and already have the capacity to grow, harvest, store, and transport them. Forage crops offer additional flexibility in management because they can be used for biomass or forage and the land can be returned to other uses or put into crop rotation. Estimates indicate about 22.3 million ha of cropland, idle cropland, and cropland pasture will be needed for biomass production in 2030. Converting these lands to large scale cellulosic energy farming could push the traditional forage-livestock industry to ever more marginal lands. Furthermore, encouraging bioenergy production from marginal lands could directly compete with forage-livestock production. PMID:19325783

Sanderson, Matt A; Adler, Paul R

2008-05-01

205

Perennial Forages as Second Generation Bioenergy Crops  

PubMed Central

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 (Phalaris arundinacea L.), and alfalfa (Medicago sativa L.). An advantage of using forages as bioenergy crops is that farmers are familiar with their management and already have the capacity to grow, harvest, store, and transport them. Forage crops offer additional flexibility in management because they can be used for biomass or forage and the land can be returned to other uses or put into crop rotation. Estimates indicate about 22.3 million ha of cropland, idle cropland, and cropland pasture will be needed for biomass production in 2030. Converting these lands to large scale cellulosic energy farming could push the traditional forage-livestock industry to ever more marginal lands. Furthermore, encouraging bioenergy production from marginal lands could directly compete with forage-livestock production. PMID:19325783

Sanderson, Matt A.; Adler, Paul R.

2008-01-01

206

Worker honey bee pheromone regulation of foraging ontogeny  

NASA Astrophysics Data System (ADS)

The evolution of sociality has configured communication chemicals, called primer pheromones, which play key roles in regulating the organization of social life. Primer pheromones exert relatively slow effects that fundamentally alter developmental, physiological, and neural systems. Here, I demonstrate how substances extracted from the surface of foraging and young pre-foraging worker bees regulated age at onset of foraging, a developmental process. Hexane-extractable compounds washed from foraging workers increased foraging age compared with controls, whereas extracts of young pre-foraging workers decreased foraging age. This represents the first known direct demonstration of primer pheromone activity derived from adult worker bees.

Pankiw, Tanya

207

Kinetics of digestion f forage fiber components  

E-print Network

contained ei+her e 2 forage sample or 1 g sample of acid washed, ashed, neu- tral detergent washed asbestos to simulate inert bulk in- cspa'ole of digestion. The forag~ sample gave an indica- tion of digestibility, while the bag containing asbestos gave... material. Forage samples of 1. 2 to 1. 3 g w re used in duplicate with 0. 5 g asbestos or 1. 0 g chromosorb-0 to obtain ex indication of digestibilities and. influx from the rumen, respectively. 14aximum digestibility of NDF was o...

Van Hellen, Russell William

1974-01-01

208

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

209

SYMPOSIUM: FORAGE UTILIZATION BY THE LACTATING COW Effect of Forage Quality on Intake and Forage-Concentrate Interactions  

Microsoft Academic Search

Regulation of intake in ruminants is primarily a function of physical fill for diets that are energetically dilute and less digestible, such as high-forage diets; but intake becomes primarily a function of metabolic control for diets that are energetically dense and highly digestible, such as high-concentrate diets. Physical limitation of all-forage diets fed to growing ruminants is generally considered to

D. R. WALDO

210

The Case for Cyber Foraging Rajesh Balan  

E-print Network

and and Hen-I Yang Carnegie Mellon University and Intel Research Pittsburgh rajesh@cs.cmu.edu Abstract foraging? Desktop computers at discount stores already sell for a few hundred dollars, with prices

Flinn, Jason

211

Forage Bermudagrass: Selection, Establishment and Management  

E-print Network

Hybrid bermudagrass can produce high-quality forage, but as with any other crop, proper variety selection, soil preparation, planting, fertility, irrigation management, and timing of harvest are necessary to ensure the highest quality feed...

Stichler, Charles; Bade, David H.

2003-04-04

212

Individual lifetime pollen and nectar foraging preferences in bumble bees  

NASA Astrophysics Data System (ADS)

Foraging specialization plays an important role in the ability of social insects to efficiently allocate labor. However, relatively little is known about the degree to which individual bumble bees specialize on collecting nectar or pollen, when such preferences manifest, and if individuals can alter their foraging preferences in response to changes in the colony workforce. Using Bombus impatiens, we monitored all foraging visits made by every bee in multiple colonies and showed that individual foragers exhibit consistent lifetime foraging preferences. Based upon the distribution of foraging preferences, we defined three forager types (pollen specialists, nectar specialists, and generalists). In unmanipulated colonies, 16-36 % of individuals specialized (?90 % of visits) on nectar or pollen only. On its first day of foraging, an individual's foraging choices (nectar only, pollen only, or nectar and pollen) significantly predicted its lifetime foraging preferences. Foragers that only collected pollen on their first day of foraging made 1.61- to 1.67-fold more lifetime pollen foraging visits (as a proportion of total trips) than foragers that only collected nectar on their first foraging day. Foragers were significantly larger than bees that stayed only in the nest. We also determined the effect of removing pollen specialists at early (brood present) or later (brood absent) stages in colony life. These results suggest that generalists can alter their foraging preferences in response to the loss of a small subset of foragers. Thus, bumble bees exhibit individual lifetime foraging preferences that are established early in life, but generalists may be able to adapt to colony needs.

Hagbery, Jessica; Nieh, James C.

2012-10-01

213

Nutritive characteristics of forage chemical components  

E-print Network

. Mean Content in Forages of Acid-Detergent Fiber (ADF) and the Summation of Cellulose (CG) and Acid Insoluble Lignin (AL) Mean Composition in Forages of Cellulose and Lignin determined by Two Methods 47 5 ~ 6. Analysis of Variance associated.... A C , 1965) Introduction of Newer Chemical Procedures and Methods It is of primary importance to remember that the main constituents of the crude fiber fraction (cellulose, hemi- cellulose and lignin) are also included in varying amounts...

Buentello, Jose Luis

1969-01-01

214

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

215

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

216

Age, growth, and food of northern pike in eastern Lake Ontario  

USGS Publications Warehouse

Northern pike (Esox lucius) from eastern Lake Ontario were sampled with gill nets and trap nets in 1972-1973. Fish of age-groups IV, V, and VI were predominant in the catch. Although males were slightly longer after the 1st yr of life, females gained a 25-mm advantage in the 2nd yr and a 30-mm advantage in the 3rd yr. In later years, the increments of growth of males and females were similar. All males were mature after 2 yr and females after 3 yr. The stomachs of northern pike contained only fish; the alewife (Alosa pseudoharengus) was the principal forage species consumed. Electivity indexes for alewives, white perch (Morone americana), and yellow perch (Perca flavescens), the three most common species in the diet, indicated a positive selection for alewives that increased from June to October during a period when the relative abundance of alewives steadily decreased.

Wolfert, David R.; Miller, Terence J.

1978-01-01

217

Forage and bioenergy feedstock production from hybrid forage sorghum and sorghum x sudangrass hybrids  

Technology Transfer Automated Retrieval System (TEKTRAN)

As the bioenergy industry expands, producers choosing to shift current forage crop production to dedicated biomass crops will find it advantageous to grow low risk multi-purpose crops that maximize management options. Hybrid forage sorghums (HFS) and sorghum by sudangrass hybrids (SSG) are capable...

218

Limited foraging flexibility: increased foraging effort by a marine predator does not buffer against scarce prey  

Microsoft Academic Search

Flexibility in activity time budgets allows animals to cope with heterogeneous and changing environments. Many marine predators, such as seabirds, exhibit flexibility in their foraging behaviour to buffer reproductive success against periods of low prey availability. Over 3 years, 2004 to 2006, we studied the foraging behaviour of a threatened seabird, the marbled murrelet Brachyramphus marmoratus in southwestern Vancouver Island,

Robert A. Ronconi; Alan E. Burger

2008-01-01

219

Isolation of viral haemorrhagic septicaemia virus from muskellunge, Esox masquinongy (Mitchill), in Lake St Clair, Michigan, USA reveals a new sublineage of the North American genotype.  

PubMed

Viral haemorrhagic septicaemia virus (VHSV) was isolated from muskellunge, Esox masquinongy (Mitchill), caught from the NW portion of Lake St Clair, Michigan, USA in 2003. Affected fish exhibited congestion of internal organs; the inner wall of the swim bladder was thickened and contained numerous budding, fluid-filled vesicles. A virus was isolated using fish cell lines inoculated with a homogenate of kidney and spleen tissues from affected fish. Focal areas of cell rounding and granulation appeared as early as 24 h post-inoculation and expanded rapidly to destroy the entire cell sheet by 96 h. Electron microscopy revealed virions that were 170-180 nm in length by 60-70 nm in width having a bullet-shaped morphology typical of rhabdoviruses. The virus was confirmed as VHSV by reverse transcriptase-polymerase chain reaction. Sequence analysis of the entire nucleoprotein and glycoprotein genes revealed the virus was a member of the North American genotype of VHSV; however, the isolate was sufficiently distinct to be considered a separate sublineage, suggesting its origin may have been from marine species inhabiting the eastern coastal areas of the USA or Canada. PMID:17026670

Elsayed, E; Faisal, M; Thomas, M; Whelan, G; Batts, W; Winton, J

2006-10-01

220

Scale of heterogeneity of forage production and winter foraging by elk and bison  

E-print Network

The relationship between fine-scale spatial patterns of forage abundance and the feeding patterns of large ungulates is not well known. We compared these patterns for areas grazed in winter by elk and bison in a sagebrush-grassland landscape in northern Yellowstone National Park. At a fine scale, the spatial distribu-tion of mapped feeding stations in 30 m x 30 m sites was found to be random where there were no large patches devoid of vegetation. In areas similar to the mapped sites, the underlying spatial distribution pattern of biomass was also determined to be random. At a broad scale, forage biomass differed among communities across the northern range but forage quality did not. These results suggest that ungulates are feeding random-ly within forage patches (fine scale) but may select feeding sites based upon forage abundance at broader, landscape scales. Contrary to what has been suggested in other systems, ungulates were not ‘overmatching’ at finer scales. 1.

L. L. Wallace; W. H. Romme; R. V. O’neil; Yegang Wu

221

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Forage production crop insurance provisions. 457.117 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.117 Forage...

2014-01-01

222

7 CFR 457.151 - Forage seeding crop insurance provisions.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Forage seeding crop insurance provisions. 457.151 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.151 Forage...

2013-01-01

223

7 CFR 457.151 - Forage seeding crop insurance provisions.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Forage seeding crop insurance provisions. 457.151 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.151 Forage...

2014-01-01

224

7 CFR 457.151 - Forage seeding crop insurance provisions.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Forage seeding crop insurance provisions. 457.151 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.151 Forage...

2012-01-01

225

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Forage production crop insurance provisions. 457.117 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.117 Forage...

2013-01-01

226

7 CFR 457.151 - Forage seeding crop insurance provisions.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Forage seeding crop insurance provisions. 457.151 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.151 Forage...

2011-01-01

227

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Forage production crop insurance provisions. 457.117 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.117 Forage...

2011-01-01

228

7 CFR 457.151 - Forage seeding crop insurance provisions.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Forage seeding crop insurance provisions. 457.151 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.151 Forage...

2010-01-01

229

7 CFR 457.117 - Forage production crop insurance provisions.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Forage production crop insurance provisions. 457.117 Section 457...Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.117 Forage...

2012-01-01

230

Optimal Lévy-flight foraging in a finite landscape.  

PubMed

We present a simple model to study Lévy-flight foraging with a power-law step-size distribution [P(l) ? l-?] in a finite landscape with countable targets. We find that different optimal foraging strategies characterized by a wide range of power-law exponent ?opt, from ballistic motion (?opt ? 1) to Lévy flight (1 < ?opt < 3) to Brownian motion (?opt ? 3), may arise in adaptation to the interplay between the termination of foraging, which is regulated by the number of foraging steps, and the environmental context of the landscape, namely the landscape size and number of targets. We further demonstrate that stochastic returning can be another significant factor that affects the foraging efficiency and optimality of foraging strategy. Our study provides a new perspective on Lévy-flight foraging, opens new avenues for investigating the interaction between foraging dynamics and the environment and offers a realistic framework for analysing animal movement patterns from empirical data. PMID:25631566

Zhao, Kun; Jurdak, Raja; Liu, Jiajun; Westcott, David; Kusy, Branislav; Parry, Hazel; Sommer, Philipp; McKeown, Adam

2015-03-01

231

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

232

7 CFR 407.13 - Group risk plan for forage.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 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...

2010-01-01

233

Optimal Lévy-flight foraging in a finite landscape  

PubMed Central

We present a simple model to study Lévy-flight foraging with a power-law step-size distribution in a finite landscape with countable targets. We find that different optimal foraging strategies characterized by a wide range of power-law exponent ?opt, from ballistic motion (?opt ? 1) to Lévy flight (1 < ?opt < 3) to Brownian motion (?opt ? 3), may arise in adaptation to the interplay between the termination of foraging, which is regulated by the number of foraging steps, and the environmental context of the landscape, namely the landscape size and number of targets. We further demonstrate that stochastic returning can be another significant factor that affects the foraging efficiency and optimality of foraging strategy. Our study provides a new perspective on Lévy-flight foraging, opens new avenues for investigating the interaction between foraging dynamics and the environment and offers a realistic framework for analysing animal movement patterns from empirical data. PMID:25631566

Zhao, Kun; Jurdak, Raja; Liu, Jiajun; Westcott, David; Kusy, Branislav; Parry, Hazel; Sommer, Philipp; McKeown, Adam

2015-01-01

234

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

235

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

236

A DIGITAL PHOTOGRAPHIC TECHNIQUE FOR ASSESSING FORAGE UTILIZATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Changes in forage utilization have been difficult to measure nondestructively without some level of subjectivity. This subjectivity, combined with a lack of reproducibility of visual estimates, has made forage utilization measurement techniques a topic of considerable discussion. The objective of ...

237

Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for  

E-print Network

Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for methods used #12;Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for methods used Laboratory Phosphorus recommendations applicable for methods used by laboratory. Mehlich III by ICP only

238

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

239

Insect communication: 'no entry' signal in ant foraging.  

PubMed

Forager ants lay attractive trail pheromones to guide nestmates to food, but the effectiveness of foraging networks might be improved if pheromones could also be used to repel foragers from unrewarding routes. Here we present empirical evidence for such a negative trail pheromone, deployed by Pharaoh's ants (Monomorium pharaonis) as a 'no entry' signal to mark an unrewarding foraging path. This finding constitutes another example of the sophisticated control mechanisms used in self-organized ant colonies. PMID:16306981

Robinson, Elva J H; Jackson, Duncan E; Holcombe, Mike; Ratnieks, Francis L W

2005-11-24

240

Rangeland Risk Management for Texans: Forage Quality and Quantity  

E-print Network

. Recognizing and Correcting Forage Quantity Problems Forage quantity can also be a problem, even when there appears to be plenty of standing crop. Grazing animals have very definite food preferences. They instinctively look for green plant material... the nutrient requirements of the mothers, or a combination of these approaches. Managing calving, lambing and kidding seasons to match forage pro- duction seasons can help reduce both forage quality and quantity problems. Flexible stocking plans also are impor...

Lyons, Robert K.

2000-11-01

241

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

242

EFFECTS OF FORAGE MANAGEMENT ON PASTURE PRODUCTIVITY AND PHOSPHORUS CONTENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objectives of the current study were to determine the amounts of above- and below-ground plant biomass production, phosphorus (P) uptake by forage, and P concentration of cool-season grass forage as influenced by management and season. Five forage management treatments were evaluated over three...

243

Foraging pits, litter and plant germination in an arid shrubland  

Microsoft Academic Search

Many animals create soil surface depressions (pits) while foraging for subterranean resources. Foraging pits typically fill with litter, organic debris and seed, retain moisture, and become hotspots for plant germination. This study aimed to examine whether artificial foraging pits, which mimic those created by Greater bilbies (Macrotis lagotis) and Burrowing bettongs (Bettongia lesueur), develop into patches of enhanced plant germination

Alex I. James; David J. Eldridge; Katherine E. Moseby

2010-01-01

244

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

245

Sap Analysis for Diagnosis of Nitrate Accumulation in Cereal Forages  

E-print Network

on the concentration of nitrate in the forage and the level of consumption. Recommendations for mixing forage of nitrate levels in cured hay (Tables 1 and 2). We sought to develop a new quicktest for nitrate in cereal the lower nodes of selected small grain forages at the time of harvest are correlated with nitrate levels

Lawrence, Rick L.

246

Factors influencing the field germination of forage kochia  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage kochia is a drought and salt tolerant perennial, semi-shrub that has proven to be valuable forage in the western U.S., but also difficult to establish. This study evaluated the effects that age of seed, subspecies, and planting date have on forage kochia seed germination in the field. Seed ...

247

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

248

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

249

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

250

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

251

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

252

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

E-print Network

on rubbish dumps or slaughter- house wastes (Tortosa et al. 1995, 2003). Similar foraging behaviour seemsSHORT 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

Boyer, Edmond

253

A Hybrid, Multi-Agent Model of Foraging Bottlenose Dolphins  

E-print Network

A Hybrid, Multi-Agent Model of Foraging Bottlenose Dolphins Musad Haque Amir Rahmani Magnus, and unmanned underwater vehicles. We draw inspiration from the foraging techniques of bottlenose dolphins foraging bottlenose dolphins, Tursiops truncatus. Our goal is to model this inherently hybrid biologically

Egerstedt, Magnus

254

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 # Springer-Verlag 2006 Abstract Foragers of the stingless bees genus Melipona may produce intranidal sounds

Nieh, James

255

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

256

' 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

257

The mechanisms of interference competition: two experiments on foraging waders  

Microsoft Academic Search

Models of population dynamics that include interference competition have often been applied to foraging waders and less so to other foragers, even though these models are, in principle, generally applicable. At present, however, it is still unclear whether interference competition is of importance for foraging waders. To support this idea experimental evidence and knowledge of the mechanisms underlying interference effects

Wouter K. Vahl; Jaap van der Meer; Franz J. Weissing; Diederik van Dullemen; Theunis Piersma

2005-01-01

258

Foraging behaviour of Armillaria rhizomorph systems.  

PubMed

The foraging behaviour of Armillaria rhizomorph systems is poorly understood owing to their cryptic position within the soil. We investigated foraging in a homogeneous environment (i.e. agar), finding that rhizomorph systems of the more parasitic species, A. mellea, A. ostoyae, and A. tabescens, lacked melanin and the approximately cylindrical cord-like form observed in the field. In contrast, rhizomorph systems of the more saprotrophic species, A. calvescens, A. gallica, and A. sinapina, developed radially resembling those in the field. For the three saprotrophic Armillaria species, the number of rhizomorph tips, total rhizomorph length and total rhizomorph surface area were significantly positively correlated with increasing rhizomorph system diameter and elapsed time in two developmental tests. However, the fractal dimension (D), used as a measure of foraging intensity, was temporally invariable, suggesting that one component of foraging behaviour is innate. In a heterogeneous environment (i.e. sand) and in the absence of a potential nutrient source, we observed that rhizomorph systems of A. gallica most often developed asymmetrically. While rhizomorph foraging was unresponsive to the lateral placement of an uncolonised stem segment, we were able to demonstrate directional growth toward an uncolonised Quercus velutina stem segment placed above or below the colonised source stem segment. When neighboring rhizomorph systems were conspecific genets of A. gallica, we observed that the growth of one rhizomorph system was directed toward zones unoccupied by its neighbour. However, the foraging intensity of the neighbouring genets, as measured by fractal dimension (D), was unaffected by the proximity of a neighbour. When neighbouring rhizomorph systems represented different species (A. gallica and A. mellea), A. gallica rhizomorph systems produced more total length and more foraging tips but concentrated their rhizomorph production away from the neighbouring A. mellea genet. In contrast, A. mellea rhizomorph systems produced significantly more foraging tips per unit length, both overall and in the zone of confrontation with the neighbouring A. gallica genet. Our observations are consistent with field observations of territoriality among Armillaria genets, and provide evidence that rhizomorph systems of more parasitic Armillaria spp. are able to compete effectively with the larger rhizomorph systems of more saprotrophic Armillaria species. PMID:16279413

Mihail, Jeanne D; Bruhn, Johann N

2005-11-01

259

Relative cattle preference of 24 forage kochia (Kochia prostrata) entries and its relation to forage nutritive value and morphological characteristics  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage kochia [Kochia prostrata (L. Shrad.)] has been shown to have potential as a nutritious fall and winter forage on western rangelands; however, its utilization by livestock is not well understood. This study was conducted to determine differences in cattle utilization among 24 forage kochia en...

260

7 CFR 1437.401 - Forage.  

Code of Federal Regulations, 2010 CFR

...ASSISTANCE PROGRAM Determining Coverage of Forage Intended for Animal...this part is limited to mature vegetation, as determined by CCC...period in order to preserve vegetation and prevent erosion, or...seeding of alfalfa and similar vegetation when production is...

2010-01-01

261

7 CFR 1437.401 - Forage.  

Code of Federal Regulations, 2013 CFR

...ASSISTANCE PROGRAM Determining Coverage of Forage Intended for Animal...this part is limited to mature vegetation, as determined by CCC...period in order to preserve vegetation and prevent erosion, or...seeding of alfalfa and similar vegetation when production is...

2013-01-01

262

7 CFR 1437.401 - Forage.  

Code of Federal Regulations, 2012 CFR

...ASSISTANCE PROGRAM Determining Coverage of Forage Intended for Animal...this part is limited to mature vegetation, as determined by CCC...period in order to preserve vegetation and prevent erosion, or...seeding of alfalfa and similar vegetation when production is...

2012-01-01

263

7 CFR 1437.401 - Forage.  

Code of Federal Regulations, 2011 CFR

...ASSISTANCE PROGRAM Determining Coverage of Forage Intended for Animal...this part is limited to mature vegetation, as determined by CCC...period in order to preserve vegetation and prevent erosion, or...seeding of alfalfa and similar vegetation when production is...

2011-01-01

264

7 CFR 1437.401 - Forage.  

Code of Federal Regulations, 2014 CFR

...ASSISTANCE PROGRAM Determining Coverage of Forage Intended for Animal...this part is limited to mature vegetation, as determined by CCC...period in order to preserve vegetation and prevent erosion, or...seeding of alfalfa and similar vegetation when production is...

2014-01-01

265

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. Explaining that the whales feed by lunging repeatedly through deep shoals of krill, engulfing their own body

Martin, Paul R.

266

Human memory retrieval as Lévy foraging  

NASA Astrophysics Data System (ADS)

When people attempt to recall as many words as possible from a specific category (e.g., animal names) their retrievals occur sporadically over an extended temporal period. Retrievals decline as recall progresses, but short retrieval bursts can occur even after tens of minutes of performing the task. To date, efforts to gain insight into the nature of retrieval from this fundamental phenomenon of semantic memory have focused primarily upon the exponential growth rate of cumulative recall. Here we focus upon the time intervals between retrievals. We expected and found that, for each participant in our experiment, these intervals conformed to a Lévy distribution suggesting that the Lévy flight dynamics that characterize foraging behavior may also characterize retrieval from semantic memory. The closer the exponent on the inverse square power-law distribution of retrieval intervals approximated the optimal foraging value of 2, the more efficient was the retrieval. At an abstract dynamical level, foraging for particular foods in one's niche and searching for particular words in one's memory must be similar processes if particular foods and particular words are randomly and sparsely located in their respective spaces at sites that are not known a priori. We discuss whether Lévy dynamics imply that memory processes, like foraging, are optimized in an ecological way.

Rhodes, Theo; Turvey, Michael T.

2007-11-01

267

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

268

Purslane: A Potential Forage for Small Ruminants  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sustainable small ruminant production on small-acreage farms in Appalachia depends upon use of various plant resources to meet nutritional and health requirements of animals and provide meat products that satisfy consumer desires and expectations. While traditional forage species can supply nutrien...

269

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...

270

Investigating Optimal Foraging Theory in the Laboratory  

ERIC Educational Resources Information Center

Optimal foraging theory is a principle that is often presented in the community ecology section of biology textbooks, but also can be demonstrated in the laboratory. We introduce a lab activity that uses an interactive strategy to teach high school and/or college students about this ecological concept. The activity is ideal because it engages…

Harden, Siegfried; Grilliot, Matthew E.

2014-01-01

271

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

272

Soil Carbon Fractionation under Perennial Forage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Crop management practices can improve soil quality. Forage type and N-sources might also affect soil organic matter, especially soil carbon fractionation. The objective of this study is to evaluate the impact of legume inter-planting and compost application on soil C pools under a perennial grass mi...

273

Balancing organization and flexibility in foraging dynamics.  

PubMed

Proper pattern organization and reorganization are central problems facing many biological networks which thrive in fluctuating environments. However, in many cases the mechanisms that organize system activity oppose those that support behavioral flexibility. Thus, a balance between pattern organization and pattern flexibility is critically important for overall biological fitness. We study this balance in the foraging strategies of ant colonies exploiting food in dynamic environments. We present discrete time and space simulations of colony activity that uses a pheromone-based recruitment strategy biasing foraging towards a food source. After food relocation, the pheromone must evaporate sufficiently before foraging can shift colony attention to a new food source. The amount of food consumed within the dynamic environment depends non-monotonically on the pheromone evaporation time constant-with maximal consumption occurring at a time constant which balances trail formation and trail flexibility. A deterministic, 'mean field' model of pheromone and foragers on trails mimics our colony simulations. This reduced framework captures the essence of the flexibility-organization balance, and relates optimal pheromone evaporation to the timescale of the dynamic environment. We expect that the principles exposed in our study will generalize and motivate novel analysis across a broad range systems biology. PMID:20627107

Tabone, Michaelangelo; Ermentrout, Bard; Doiron, Brent

2010-10-01

274

Original article Worker piping associated with foraging  

E-print Network

Original article Worker piping associated with foraging in undisturbed queenright colonies of honey piping, previously reported only in association with colony disturbance or queen- lessness, was seen in undisturbed, queenright colonies. Workers piped by pressing the thorax to the comb, spreading the wings

Paris-Sud XI, Université de

275

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

276

Effects of rain damage on wilting forages  

Technology Transfer Automated Retrieval System (TEKTRAN)

One of the most common problems faced by hay or silage producers is how to manage production schedules around unfavorable weather. Inevitably, some wilting forage crops are damaged by unexpected rainfall events each year, and producers often inquire about the effects of unexpected rain damage, and w...

277

FORAGE NUTRITIVE VALUE IN AN EMULATED SILVOPASTURE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Incorporating trees into pastures may alter forage nutritive value. The objective of this study was to determine nutritive value in response to trees and slope position in an emulated (no animals) silvopasture. In 1995, black walnut (Juglans nigra L.) and honey locust (Gleditisia triacanthos L.) ...

278

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...

279

HARVESTING WINTER FORAGES TO EXTRACT MANURE NUTRIENTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Harvested hay captures soil manure nutrients which, if not utilized, could cause pollution of surface water or aquifer. This study determined yields of hay and N,P,K,Mg,Mn,Ca,Fe,Zn, and Cu of three winter forages in five harvesting systems. Dormant bermudagrass [Cynodon dactylon (L.)Pers.] sod regul...

280

Prey processing in central place foragers.  

PubMed

The importance of prey processing as an integral part of foraging behaviour has long been acknowledged, but little theoretical consideration has been given to the optimization of the processing behaviour itself. Processing renders food down to ingestible, palatable portions, and also removes non-essential mass thus reducing transport costs. Here, several models of processing are developed for a central place forager. When the forager has to make a simple choice between processing the prey and not, a critical distance from the central place can be calculated, beyond which it is optimal to process prey. If the forager also decides on how much of the prey to remove, the optimal amount to be removed can also be calculated. Imposing a ceiling on overall metabolic expenditure is shown to reduce the distances at which processing becomes the optimal strategy. The models are tested using parameters derived for a provisioning merlin, Falco columbarius, and alternative explanations as to why observed behaviours should differ from the optimal behaviour predicted are discussed. PMID:10640435

Rands, S A; Houston, A I; Gasson, C E

2000-01-21

281

Animal Methods for Evaluating Forage Quality  

Technology Transfer Automated Retrieval System (TEKTRAN)

Numerous methods are available that employ animals in the assessment of forage quality. Some of these procedures provide information needed to address very specific goals (e.g., monitoring protein adequacy), some serve as useful contributors to the efforts to accurately predict nutritive value, wher...

282

Forage harvest representation in RUSLE2  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Revised Universal Soil Loss Equation (RUSLE and RUSLE2) has long been used by USDA and others for management planning based on soil erosion and sediment delivery estimates. It has worked well for normal annual agronomic crops, but proved to be awkward for forage crops. This is partly because RU...

283

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

284

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...

285

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...

286

Anterior cingulate engagement in a foraging context reflects choice difficulty, not foraging value.  

PubMed

Previous theories predict that human dorsal anterior cingulate (dACC) should respond to decision difficulty. An alternative theory has been recently advanced that proposes that dACC evolved to represent the value of 'non-default', foraging behavior, calling into question its role in choice difficulty. However, this new theory does not take into account that choosing whether or not to pursue foraging-like behavior can also be more difficult than simply resorting to a default. The results of two neuroimaging experiments show that dACC is only associated with foraging value when foraging value is confounded with choice difficulty; when the two are dissociated, dACC engagement is only explained by choice difficulty, and not the value of foraging. In addition to refuting this new theory, our studies help to formalize a fundamental connection between choice difficulty and foraging-like decisions, while also prescribing a solution for a common pitfall in studies of reward-based decision making. PMID:25064851

Shenhav, Amitai; Straccia, Mark A; Cohen, Jonathan D; Botvinick, Matthew M

2014-09-01

287

Summertime blues: August foraging leaves honey bees empty-handed.  

PubMed

A successful honey bee forager tells her nestmates the location of good nectar and pollen with the waggle dance, a symbolic language that communicates a distance and direction. Because bees are adept at scouting out profitable forage and are very sensitive to energetic reward, we can use the distance that bees communicate via waggle dances as a proxy for forage availability, where the further the bees fly, the less forage can be found locally. Previously we demonstrated that bees fly furthest in the summer compared with spring or autumn to bring back forage that is not necessarily of better quality. Here we show that August is also the month when significantly more foragers return with empty crops (P = 7.63e-06). This provides additional support that summer may represent a seasonal foraging challenge for honey bees. PMID:25346794

Couvillon, Margaret J; Fensome, Katherine A; Quah, Shaun Kl; Schürch, Roger

2014-01-01

288

Attention as foraging for information and value  

PubMed Central

What is the purpose of attention? One avenue of research has led to the proposal that attention might be crucial for gathering information about the environment, while other lines of study have demonstrated how attention may play a role in guiding behavior to rewarded options. Many experiments that study attention require participants to make a decision based on information acquired discretely at one point in time. In real-world situations, however, we are usually not presented with information about which option to select in such a manner. Rather we must initially search for information, weighing up reward values of options before we commit to a decision. Here, we propose that attention plays a role in both foraging for information and foraging for value. When foraging for information, attention is guided toward the unknown. When foraging for reward, attention is guided toward high reward values, allowing decision-making to proceed by accept-or-reject decisions on the currently attended option. According to this account, attention can be regarded as a low-cost alternative to moving around and physically interacting with the environment—“teleforaging”—before a decision is made to interact physically with the world. To track the timecourse of attention, we asked participants to seek out and acquire information about two gambles by directing their gaze, before choosing one of them. Participants often made multiple refixations on items before making a decision. Their eye movements revealed that early in the trial, attention was guided toward information, i.e., toward locations that reduced uncertainty about value. In contrast, late in the trial, attention was guided by expected value of the options. At the end of the decision period, participants were generally attending to the item they eventually chose. We suggest that attentional foraging shifts from an uncertainty-driven to a reward-driven mode during the evolution of a decision, permitting decisions to be made by an engage-or-search strategy. PMID:24204335

Manohar, Sanjay G.; Husain, Masud

2013-01-01

289

Spatiotemporal resource distribution and foraging strategies of ants (Hymenoptera: Formicidae)  

PubMed Central

The distribution of food resources in space and time is likely to be an important factor governing the type of foraging strategy used by ants. However, no previous systematic attempt has been made to determine whether spatiotemporal resource distribution is in fact correlated with foraging strategy across the ants. In this analysis, I present data compiled from the literature on the foraging strategy and food resource use of 402 species of ants from across the phylogenetic tree. By categorizing the distribution of resources reported in these studies in terms of size relative to colony size, spatial distribution relative to colony foraging range, frequency of occurrence in time relative to worker life span, and depletability (i.e., whether the colony can cause a change in resource frequency), I demonstrate that different foraging strategies are indeed associated with specific spatiotemporal resource attributes. The general patterns I describe here can therefore be used as a framework to inform predictions in future studies of ant foraging behavior. No differences were found between resources collected via short-term recruitment strategies (group recruitment, short-term trails, and volatile recruitment), whereas different resource distributions were associated with solitary foraging, trunk trails, long-term trail networks, group raiding, and raiding. In many cases, ant species use a combination of different foraging strategies to collect diverse resources. It is useful to consider these foraging strategies not as separate options but as modular parts of the total foraging effort of a colony. PMID:25525497

Lanan, Michele

2014-01-01

290

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

291

Behavioural Syndrome in a Solitary Predator Is Independent of Body Size and Growth Rate  

PubMed Central

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

292

Utilisation of Intensive Foraging Zones by Female Australian Fur Seals  

PubMed Central

Within a heterogeneous environment, animals must efficiently locate and utilise foraging patches. One way animals can achieve this is by increasing residency times in areas where foraging success is highest (area-restricted search). For air-breathing diving predators, increased patch residency times can be achieved by altering both surface movements and diving patterns. The current study aimed to spatially identify the areas where female Australian fur seals allocated the most foraging effort, while simultaneously determining the behavioural changes that occur when they increase their foraging intensity. To achieve this, foraging behaviour was successfully recorded with a FastLoc GPS logger and dive behaviour recorder from 29 individual females provisioning pups. Females travelled an average of 118 ± 50 km from their colony during foraging trips that lasted 7.3 ± 3.4 days. Comparison of two methods for calculating foraging intensity (first-passage time and first-passage time modified to include diving behaviour) determined that, due to extended surface intervals where individuals did not travel, inclusion of diving behaviour into foraging analyses was important for this species. Foraging intensity ‘hot spots’ were found to exist in a mosaic of patches within the Bass Basin, primarily to the south-west of the colony. However, the composition of benthic habitat being targeted remains unclear. When increasing their foraging intensity, individuals tended to perform dives around 148 s or greater, with descent/ascent rates of approximately 1.9 m•s-1 or greater and reduced postdive durations. This suggests individuals were maximising their time within the benthic foraging zone. Furthermore, individuals increased tortuosity and decreased travel speeds while at the surface to maximise their time within a foraging location. These results suggest Australian fur seals will modify both surface movements and diving behaviour to maximise their time within a foraging patch. PMID:25692978

Hoskins, Andrew J.; Costa, Daniel P.; Arnould, John P. Y.

2015-01-01

293

Utilisation of intensive foraging zones by female Australian fur seals.  

PubMed

Within a heterogeneous environment, animals must efficiently locate and utilise foraging patches. One way animals can achieve this is by increasing residency times in areas where foraging success is highest (area-restricted search). For air-breathing diving predators, increased patch residency times can be achieved by altering both surface movements and diving patterns. The current study aimed to spatially identify the areas where female Australian fur seals allocated the most foraging effort, while simultaneously determining the behavioural changes that occur when they increase their foraging intensity. To achieve this, foraging behaviour was successfully recorded with a FastLoc GPS logger and dive behaviour recorder from 29 individual females provisioning pups. Females travelled an average of 118 ± 50 km from their colony during foraging trips that lasted 7.3 ± 3.4 days. Comparison of two methods for calculating foraging intensity (first-passage time and first-passage time modified to include diving behaviour) determined that, due to extended surface intervals where individuals did not travel, inclusion of diving behaviour into foraging analyses was important for this species. Foraging intensity 'hot spots' were found to exist in a mosaic of patches within the Bass Basin, primarily to the south-west of the colony. However, the composition of benthic habitat being targeted remains unclear. When increasing their foraging intensity, individuals tended to perform dives around 148 s or greater, with descent/ascent rates of approximately 1.9 m•s-1 or greater and reduced postdive durations. This suggests individuals were maximising their time within the benthic foraging zone. Furthermore, individuals increased tortuosity and decreased travel speeds while at the surface to maximise their time within a foraging location. These results suggest Australian fur seals will modify both surface movements and diving behaviour to maximise their time within a foraging patch. PMID:25692978

Hoskins, Andrew J; Costa, Daniel P; Arnould, John P Y

2015-01-01

294

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

295

Understanding Forage Intake in Range Animals  

E-print Network

&M University System. 1-99 Most economically important Texas range her- bivores (livestock and native or exotic wildlife) are ruminants. Small ruminants have greater nutrient requirements per pound of body weight than large ruminants. These small ruminants... select particular kinds of forage to cope with their higher nutrient requirements. Regardless of their feeding type (grazers, intermediate feeders, or browsers, shown in Table 2), small ruminants tend to utilize plants and plant parts that are rapidly...

Lyons, Robert K.; Machen, Richard V.; Forbes, T. D. A.

1999-02-08

296

Grass management for forage and seed production  

E-print Network

for Forage and Seed Production. (August 1979) Richard John Hendler, B. S. , Tulane University Chairman of Advisory Committee: Dr. E. C. Holt This research project was conducted to explore dual use poten- tial of three species of warm season perennial... improving Agriculture in the State of Texas and especially for the support of the assistanship through which this thesis research was conducted. vi ACKNOWLEDGEMENT S The author is greatly indebted to Dr. Ethan C. Holt, the commit- tee chairman...

Hendler, Richard John

1979-01-01

297

Common Attentional Constraints in Visual Foraging  

PubMed Central

Predators are known to select food of the same type in non-random sequences or “runs” that are longer than would be expected by chance. If prey are conspicuous, predators will switch between available sources, interleaving runs of different prey types. However, when prey are cryptic, predators tend to focus on one food type at a time, effectively ignoring equally available sources. This latter finding is regarded as a key indicator that animal foraging is strongly constrained by attention. It is unknown whether human foraging is equally constrained. Here, using a novel iPad task, we demonstrate for the first time that it is. Participants were required to locate and touch 40 targets from 2 different categories embedded within a dense field of distractors. When individual target items “popped-out” search was organized into multiple runs, with frequent switching between target categories. In contrast, as soon as focused attention was required to identify individual targets, participants typically exhausted one entire category before beginning to search for the other. This commonality in animal and human foraging is compelling given the additional cognitive tools available to humans, and suggests that attention constrains search behavior in a similar way across a broad range of species. PMID:24964082

Kristjánsson, Árni; Jóhannesson, Ómar I.; Thornton, Ian M.

2014-01-01

298

Visually Guided Decision Making in Foraging Honeybees  

PubMed Central

Honeybees can easily be trained to perform different types of discrimination tasks under controlled laboratory conditions. This review describes a range of experiments carried out with free-flying forager honeybees under such conditions. The research done over the past 30 or so years suggests that cognitive abilities (learning and perception) in insects are more intricate and flexible than was originally imagined. It has become apparent that honeybees are capable of a variety of visually guided tasks, involving decision making under challenging situations: this includes simultaneously making use of different sensory modalities, such as vision and olfaction, and learning to use abstract concepts such as “sameness” and “difference.” Many studies have shown that decision making in foraging honeybees is highly flexible. The trained animals learn how to solve a task, and do so with a high accuracy, but when they are presented with a new variation of the task, they apply the learnt rules from the earlier setup to the new situation, and solve the new task as well. Honeybees therefore not only feature a rich behavioral repertoire to choose from, but also make decisions most apt to the current situation. The experiments in this review give an insight into the environmental cues and cognitive resources that are probably highly significant for a forager bee that must continually make decisions regarding patches of resources to be exploited. PMID:22719721

Zhang, Shaowu; Si, Aung; Pahl, Mario

2012-01-01

299

Short-term exploitative competition can explain human foraging patterns  

E-print Network

Theory purports that animal foraging choices evolve to maximize returns, such as net energy intake. Empirical research in both human and nonhuman animals reveals that many times foraging choices are context dependent and affected by the foraging choices of others. Yet, broad empirical facts on the link between optimal foraging patterns, competition and context-dependent information are only now emerging due to the complication of gathering field data or constructing experiments. Here, we analyze foraging choices by a cohort of professional day traders who face the trade-off of trading the same stock multiple times in a row---patch exploitation---or switching to a different stock---patch exploration---with potentially higher returns. Our findings indicate that traders' foraging patterns are characterized by short-term comparative returns that decrease in proportion to patch exploitation and exploration, a novel measure that captures the difference between a trader's resource intake and the competitors' expecte...

Saavedra, Serguei; Switanek, Nicholas; Uzzi, Brian

2012-01-01

300

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

301

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

302

Optimum forage-beef systems for East Texas  

E-print Network

warrant research to determine the most profitable forage and beef systems for East Texas. The objectives of the study included determining the least cost forage system for a cow-calf operation with different calving seasons and determining the most... profitable stage of production to sell calves with available forage resources. To accomplish these objectives, linear programming techniques were used to portray and analyze East Texas conditions. An analysis of the fall and spring calving systems...

Poenisch, Kenneth Ray

1975-01-01

303

Sex differences in giraffe foraging behavior at two spatial scales  

Microsoft Academic Search

We test predictions about differences in the foraging behaviors of male and female giraffes (Giraffa camelopardalis tippelskirchi Matchie) that derive from a hypothesis linking sexual size dimorphism to foraging behavior. This body-size hypothesis predicts\\u000a that males will exhibit specific behaviors that increase their dry-matter intake rate relative to females. Foraging behavior\\u000a was examined at two hierarchical levels corresponding to two

Tim F. Ginnett; Montague W. Demment

1997-01-01

304

Effect of Nitrogen Fertilization and Forage Maturity on the Nutritive Value of Bahiagrass  

E-print Network

Bahiagrass (paspalum notatum), a forage resource in the southern United States, often has lower forage quality than other forages, but may require fewer nutrient inputs. Our objectives were to determine the effects of N fertilization and maturity...

Kenney, Nicole M

2012-07-11

305

78 FR 23738 - Monsanto Company and Forage Genetics International (FGI); Availability of Petition for...  

Federal Register 2010, 2011, 2012, 2013, 2014

...APHIS-2013-0013] Monsanto Company and Forage Genetics International (FGI); Availability...from the Monsanto Company and Forage Genetics International (FGI) seeking a determination...from the Monsanto Company and Forage Genetics International (FGI) seeking a...

2013-04-22

306

75 FR 68321 - Forage Genetics International; Supplemental Request for Partial Deregulation of Roundup Ready...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. APHIS-2007-0044] Forage Genetics International; Supplemental Request...partial deregulation'' from Forage Genetics International for the planting, harvesting...documents submitted to the Agency from Forage Genetics International requesting a...

2010-11-05

307

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

308

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

309

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

310

Annual Summer Forages for West Texas Including Brown Mid-Rib (BMR) and Photoperiod Sensitive Forages  

E-print Network

in the soft dough stage though quality is lower. As a rule of thumb the optimum time to harvest forage sorghum for silage is at the soft dough stage in the grain. See page 4 for examples. For best regrowth after haying

Mukhtar, Saqib

311

Scale of heterogeneity of forage production and winter foraging by elk and bison  

Microsoft Academic Search

The relationship between fine-scale spatial patterns of forage abundance and the feeding patterns of large ungulates is not well known. We compared these patterns for areas grazed in winter by elk and bison in a sagebrush-grassland landscape in northern Yellowstone National Park. At a fine scale, the spatial distribution of mapped feeding stations in 30 m × 30 m sites

L. L. Wallace; M. G. Turner; W. H. Romme; R. V. O'Neill; Yegang Wu

1995-01-01

312

Eye size, foraging methods and the timing of foraging in shorebirds  

Microsoft Academic Search

Summary 1. Birds with large eyes can achieve a greater pupil diameter and\\/or focal length, and hence, all other things being equal, greater visual sensitivity and resolution than birds with small eyes. Thus eye size is predicted to reflect adaptations to ecology. 2. We tested three predictions about the relationships between eye size, foraging method (from wholly visual to tactile

R. J. THOMAS; T. SZEKELY; R. F. POWELL; I. C. CUTHILL

2006-01-01

313

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

314

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

315

Negative impact of manganese on honeybee foraging.  

PubMed

Anthropogenic accumulation of metals such as manganese is a well-established health risk factor for vertebrates. By contrast, the long-term impact of these contaminants on invertebrates is mostly unknown. Here, we demonstrate that manganese ingestion alters brain biogenic amine levels in honeybees and fruit flies. Furthermore, we show that manganese exposure negatively affects foraging behaviour in the honeybee, an economically important pollinator. Our findings indicate that in addition to its direct impact on human health, the common industrial contaminant manganese might also have indirect environmental and economical impacts via the modulation of neuronal and behavioural functions in economically important insects. PMID:25808001

Søvik, Eirik; Perry, Clint J; LaMora, Angie; Barron, Andrew B; Ben-Shahar, Yehuda

2015-03-01

316

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. PMID:25538724

Lee, Michael R. F.

2014-01-01

317

Nutrient-Specific Foraging in Invertebrate Predators  

NASA Astrophysics Data System (ADS)

Many herbivores and omnivores adjust their food selection behavior to regulate the intake of multiple nutrients. Carnivores, however, are generally assumed to optimize the rate of prey capture rather than select prey according to nutrient composition. We showed experimentally that invertebrate predators can forage selectively for protein and lipids to redress specific nutritional imbalances. This selection can take place at different stages of prey handling: The predator may select among foods of different nutritional composition, eat more of a prey if it is rich in nutrients that the predator is deficient in, or extract specific nutrients from a single prey item.

Mayntz, David; Raubenheimer, David; Salomon, Mor; Toft, Søren; Simpson, Stephen J.

2005-01-01

318

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...

319

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

320

Alfalfa and forage kochia improve nutritive value of semiarid rangelands  

Technology Transfer Automated Retrieval System (TEKTRAN)

Improving forage quality on semiarid grazing lands of the western United States is challenging. This study compared the late summer forage quality parameters crude protein (CP) and neutral detergent fiber (NDF) of 'Vavilov' Siberian wheatgrass (Agropyron fragile). 'Mustang' Altai wildrye (Leymus ang...

321

Advances and Challenges in Breeding Forages with Improved Quality  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nearly 50 years have passed since the initial efforts to select and breed forage grasses with increased digestibility at the Welsh Plant Breeding Station, Aberystwyth, Wales and the USDA-ARS, Tifton, Georgia. Early efforts to improve forage quality were viewed with extreme skepticism by many breede...

322

Introduction King penguins perform extended foraging dive bouts, with  

E-print Network

3344 Introduction King penguins perform extended foraging dive bouts, with long (5·min) and deep aerobically (Froget et al., 2004). In the king penguin, a surface interval exceeding 15·min has been is why do king penguins stop foraging, sometimes for hours, during a period when food may be readily

Fahlman, Andreas

323

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

324

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, Mary C.; Grossman, G.D.

1992-01-01

325

Original article The foraging behaviour of honey bees  

E-print Network

. Whether collecting nectar or pollen, bumble bees almost always approached a flower in a manner that pollen of the flower. Although they rarely forage pollen on cranberry, a few honey bee foragers collected pollen or collected pollen than did bumble bees. In addition, honey bees had more mixed pollen loads and were slower

Paris-Sud XI, Université de

326

Meat Production from Forages in the Northeast1  

Microsoft Academic Search

The purposes of this paper were to determine the animal-forage management practices used in the Northeast and to review practices which may increase efficiency of utilization. University agron- omy and animal science specialists and producers in 12 Northeastern states were surveyed by mail questionnaire. Pertinent results are presented and are related to animal-forage management practices which have been developed and

L. L. Wilson; W. C. Stringer

1981-01-01

327

Evapotranspiration of corn and forage sorghum for silage  

Technology Transfer Automated Retrieval System (TEKTRAN)

In the U.S. Southern High Plains, dairies have expanded and have increased the regional demand for forage and silage. The objectives were to measure water use and determine crop coefficients for corn (Zea mays L.) and forage sorghum (Sorghum bicolor (L.) Moench) produced for silage on the Southern ...

328

Brood pheromone regulates foraging activity of honey bees (Hymenoptera: Apidae).  

PubMed

Brood pheromone modulated the foraging behavior of commercial honey bee, Apis mellifera L., colonies pollinating a 10-ha market garden of cucumber, Cucurbita pepo L., and zucchini, Cucumis saticus L., in Texas in late autumn. Six colonies were randomly selected to receive 2000 larval equivalents of brood pheromone and six received a blank control. The ratio of pollen to nonpollen foragers entering colonies was significantly greater in pheromone-treated colonies 1 h after treatment. Pheromone-treated foragers returned with pollen load weights that were significantly heavier than controls. Pollen returned by pheromone-treated foragers was 43% more likely to originate from the target crop. Number of pollen grains washed from the bodies of nonpollen foragers from pheromone-treated colonies was significantly greater than controls and the pollen was 54% more likely to originate from the target crop. Increasing the foraging stimulus environment with brood pheromone increased colony-level foraging and individual forager efforts. Brood pheromone is a promising technology for increasing the pollination activity and efficiency of commercial honey bee colonies. PMID:15279247

Pankiw, Tanya

2004-06-01

329

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

330

Comparative sucrose responsiveness in Apis mellifera and A. cerana foragers.  

PubMed

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

331

Livestock responses to complementary forages in shortgrass steppe  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage gaps for livestock producers exist in the spring and fall in shortgrass steppe because of dominance by the perennial warm-season grass blue grama (Bouteloua gracilis). Livestock gains of yearling Hereford heifers were evaluated during 1996-1999 on two complementary forage grasses [‘Bozoisky-S...

332

Strategies for Energy Optimisation in a Swarm of Foraging Robots  

Microsoft Academic Search

This paper presents a simple adaptation mechanism to auto- matically adjust the ratio of foragers to resters (division of labour) in a swarm of foraging robots and hence maximise the net energy income to the swarm. Three adaptation rules are introduced based on local sensing and communications. Individual robots use internal cues (successful food retrieval), environmental cues (collisions with teammates

Wenguo Liu; Alan F. T. Winfield; Jin Sa; Jie Chen; Lihua Dou

2006-01-01

333

Two Foraging Algorithms for Robot Swarms Using Only Local Communication  

E-print Network

1 Two Foraging Algorithms for Robot Swarms Using Only Local Communication Nicholas R. Hoff III is to program a swarm of simple robots, with minimal communication and individual capability, to perform to build algorithms for robot swarms. Ant colony foraging is our primary example. Ants use pheromones

Napp, Nils

334

Sampling Hay Bales and Pastures for Forage Analysis  

E-print Network

of grass should be sampled separately. To gather a subsample, cut or tear the forage at the final forage height after grazing. Be careful not to pull the entire plant out of the ground. Gather sub- samples from ten to fifteen areas within a given pasture...

Provin, Tony; Pitt, John L.

2002-05-03

335

FORAGING SUCCESS AND TREE SPECIES USE IN THE LEAST FLYCATCHER  

Microsoft Academic Search

.,BSTRACT.--I examined the effect of tree species morphology on foraging behavior in a hover-gleaning bird species, the Least Flycatcher (Empidonax minimus). Birds in four breeding territories in northern Wisconsin displayed nonsignificant differences in an index of forag- ing success (S) among four tree species of divergent morphology. However, significant vari- ation in S occurred among the three tree species common

CHRISTOPHER M. ROGERS

336

Livestock Responses to Complementary Forages in Shortgrass Steppe  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage gaps for livestock producers exist in the spring and fall in shortgrass steppe because of dominance by the perennial warm-season grass blue grama (Bouteloua gracilis). Livestock gains of yearling Hereford heifers were evaluated during 1996-1999 on two complementary forage grasses [‘Bozoisky-S...

337

Positional Communication and Private Information in Honeybee Foraging Models  

E-print Network

Positional Communication and Private Information in Honeybee Foraging Models Peter Bailis1.werfel@wyss.harvard.edu Abstract. Honeybees coordinate foraging efforts across vast areas through a complex system of advertising-quality food sources and oversubscribing them. 1 Introduction Honeybee colonies are well

Napp, Nils

338

Historical introduction: on widely foraging for Kalahari lizards  

E-print Network

Historical introduction: on widely foraging for Kalahari lizards RAYMOND B. HUEY Department oj, and what insights of others helped channel our thinking? When Eric began studying US desert lizards of iguanids. This lizard world was clearly dichotomous in terms of foraging behavior. In his 1966 paper

Huey, Raymond B.

339

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

340

2014 Soil Testing Form Corn, Forage, Pasture & Hay Instructions  

E-print Network

calculated Cation Exchange Capacity (CEC), base saturation and phosphorus saturation. Organic Matter includes2014 Soil Testing Form ­ Corn, Forage, Pasture & Hay Instructions: - Soil sampling instructions BU 80 to 90 BU #12;2014 Soil Testing Form ­ Corn, Forage, Pasture & Hay ­ Page 2 Sampling

New Hampshire, University of

341

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

342

Grazing management for fall-grown oat forages  

Technology Transfer Automated Retrieval System (TEKTRAN)

For the dairy (or beef) industry, the options for producing a late-summer emergency forage crop are limited, mostly because the growing season in Wisconsin is relatively short. Recent research has shown that oat, seeded in late-summer, can provide an excellent source of emergency forage before winte...

343

SEASONAL MORPHOLOGY AND FORAGE QUALITY OF TEMPERATE GRASSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage quality of grazed swards is closely associated with the contribution and quality of morphological components. We determined leaf and stem fraction dry matter and forage quality trends for temperate perennial grasses at two Wisconsin locations. After reaching 15 to 20 cm height, primary spri...

344

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

345

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

346

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

347

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

348

STOCKPILED FORAGE KOCHIA TO MAINTAIN BEEF COWS DURING WINTER  

Technology Transfer Automated Retrieval System (TEKTRAN)

Extending grazing into the fall and winter, as opposed to feeding of harvested forages, can increase the sustainability of cattle ranching in the western U.S. This study was conducted to determine the economic value of grazing stockpiled forage kochia (Kochia prostrata [L.] Scrad.) and crested whea...

349

Research Note Effects of Coastal Lighting on Foraging Behavior  

E-print Network

, particularly in coastal systems. Light pollution alters the behavior of sea turtles during nesting; thereforeResearch Note Effects of Coastal Lighting on Foraging Behavior of Beach Mice BRITTANY L. BIRD, LYN on the foraging behavior of Santa Rosa beach mice ( Peromyscus polionotus leucocephalus). We compared patch use

Branch, Lyn C.

350

Genetics of postweaning performance of beef cattle on forage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Increases in the costs of feed grains have revived interest in increasing the use of forages and grazing in order to either market as forage-finished beef or to produce heavy calves that will finish on less grain. However, little is known about the interactions of animal genetics and grazing enviro...

351

PATCH BURNING EFFECTS ON FORAGE UTILIZATION AND GRAZING DISTRIBUTION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Post-fire forage growth is known to be a strong attractant for large herbivores. However, fire has generally been avoided as a grazing distribution tool for fear of localized over utilization of forage resources. Our objectives were to determine cattle grazing preference for burned sites relative ...

352

Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for  

E-print Network

Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for methods used 20 15 5 0 #12;Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable by laboratory. Mehlich III by ICP only. Phosphorus Soil Fertility Recommendations for Oil Crops 0 5 10 15 20 25

353

Promoting Interactive Learning: A Classroom Exercise to Explore Foraging Strategies  

ERIC Educational Resources Information Center

We describe a classroom exercise to allow students to explore foraging strategies in higher vertebrates. The exercise includes an initial interactive session in which students act as predators and are guided through foraging simulations, and a subsequent student-led session where classmates are employed as experimental subjects. Students rated the…

Beaumont, Ellen S.; Rowe, Graham; Mikhaylov, Natalie S.

2012-01-01

354

LIVESTOCK FORAGE CONDITIONING AMONG 6 NORTHERN GREAT BASIN GRASSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Studies of Anderson and Scherzinger’s 1975 forage conditioning hypothesis have exhibited varied results. Our objectives were: 1) to evaluate late summer/early fall forage quality of crested wheatgrass (Agropyron desertorum (Fischer ex Link) Schultes), bluebunch wheatgrass (Agropyron spicatum [Pursh...

355

FORAGE SOYBEANS (GLYCINE MAX (L.) MERR.) IN THE UNITED KINGDOM  

Technology Transfer Automated Retrieval System (TEKTRAN)

Although soybeans are used principally for grain and vegetable production, they have also been used as a forage crop. Recently several cultivars and experimental lines have been bred for forage production. This coincides with the banning of meat and bone meal as a source of protein in ruminant di...

356

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

357

Honeybees foraging response in genetically diversified opium poppy.  

PubMed

Studies were carried out on honeybees foraging on plant flowers. Results showed significantly higher foraging response of honeybees (Apis mellifera) in genetically divergent narcotic plant opium poppy (Papaver somniferum). Of the 18 mutants and two locally adapted cultivars of diverse genotypes screened, eight revealed significantly greater foraging response manifesting honeybee's preference towards specific plant morphotypes. The number of flower bloom did not correspond to number of foraging bees in both mutant and cultivar plant types of opium poppy. The genotype specific foraging response of honeybees could be attributed to physico-chemical properties of opium poppy flowers. This could have implications for the development of opium alkaloid fortified honeys for novel pharmaceuticals and isolation of natural spray compounds to attract honeybee pollinators for promoting crossing and sustainable hybridity in crops. PMID:16150594

Srivastava, H K; Singh, Dwijendra

2006-09-01

358

Linking Foraging Decisions to Residential Yard Bird Composition  

PubMed Central

Urban bird communities have higher densities but lower diversity compared with wildlands. However, recent studies show that residential urban yards with native plantings have higher native bird diversity compared with yards with exotic vegetation. Here we tested whether landscape designs also affect bird foraging behavior. We estimated foraging decisions by measuring the giving-up densities (GUD; amount of food resources remaining when the final forager quits foraging on an artificial food patch, i.e seed trays) in residential yards in Phoenix, AZ, USA. We assessed how two yard designs (mesic: lush, exotic vegetation; xeric: drought-tolerant and native vegetation) differed in foraging costs. Further, we developed a statistical model to calculate GUDs for every species visiting the seed tray. Birds foraging in mesic yards depleted seed trays to a lower level (i.e. had lower GUDs) compared to birds foraging in xeric yards. After accounting for bird densities, the lower GUDs in mesic yards appeared largely driven by invasive and synanthropic species. Furthermore, behavioral responses of individual species were affected by yard design. Species visiting trays in both yard designs had lower GUDs in mesic yards. Differences in resource abundance (i.e., alternative resources more abundant and of higher quality in xeric yards) contributed to our results, while predation costs associated with foraging did not. By enhancing the GUD, a common method for assessing the costs associated with foraging, our statistical model provided insights into how individual species and bird densities influenced the GUD. These differences we found in foraging behavior were indicative of differences in habitat quality, and thus our study lends additional support for native landscapes to help reverse the loss of urban bird diversity. PMID:22927974

Lerman, Susannah B.; Warren, Paige S.; Gan, Hilary; Shochat, Eyal

2012-01-01

359

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

360

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

361

Corticosterone and foraging behavior in a pelagic seabird.  

PubMed

Because endocrine mechanisms are thought to mediate behavioral responses to changes in the environment, examining these mechanisms is essential for understanding how long-lived seabirds adjust their foraging decisions to contrasting environmental conditions in order to maximize their fitness. In this context, the hormone corticosterone (CORT) deserves specific attention because of its major connections with locomotor activities. We examined for the first time the relationships between individual CORT levels and measurements of foraging success and behavior using satellite tracking and blood sampling from wandering albatrosses (Diomedea exulans) before (pretrip CORT levels) and after (posttrip CORT levels) foraging trips during the incubation period. Plasma CORT levels decreased after a foraging trip, and the level of posttrip CORT was negatively correlated with individual foraging success, calculated as total mass gain over a foraging trip. Pretrip CORT levels were not linked to time spent at sea but were positively correlated with daily distance traveled and maximum range at sea. In this study, we were able to highlight the sensitivity of CORT levels to variation in energy intake, and we showed for the first time that individual CORT levels can be explained by variation in foraging success. Relationships between pretrip CORT levels and daily distance traveled and maximum range were independent of pretrip body mass, suggesting that slight elevations in pretrip CORT levels might facilitate locomotor activity. However, because both foraging behavior and pretrip CORT levels could be affected by individual quality, future experimental studies including manipulation of CORT levels are needed to test whether CORT can mediate foraging decisions according to foraging conditions. PMID:17390284

Angelier, Frédéric; Shaffer, Scott A; Weimerskirch, Henri; Trouvé, Colette; Chastel, Olivier

2007-01-01

362

SYMPOSIUM: IMPROVING FORAGES FOR DAIRY CATTLE The Role of Plant Breeding in Improving the Nutritive Value of Forages 1  

Microsoft Academic Search

In recent years many public forage breeders have added breeding for higher forage quality to their programs. Genetic studies have revealed that improvement of quality traits may be slow because most quality traits have intermediate to low heritability. A reasonable selection scheme under these circumstances would be to progeny test large populations of parental clones over locations, harvests, and generations.

JOHN S. SHENK

363

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

364

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

365

Effect of low-forage rations on milk production of dairy goats: Separate concentrate-forage versus mixed rations  

Microsoft Academic Search

A 2-year study investigated two methods of feeding concentrated rations to intensively reared dairy goats: separate distribution of concentrate and forage in different feeders or concentrate and forage mixed rations. Both rations consisted, on dry matter basis, 15% ryegrass hay as roughage and 85% fibrous concentrate mixture (33% corn grain, 26.5% dehydrated alfalfa, 24% dehydrated beet pulp, 10% wheat bran

Elizardo Monzón-Gil; José I. R. Castañón; Myriam R. Ventura

2010-01-01

366

Does information sharing promote group foraging?  

PubMed Central

Individuals may join groups for several reasons, one of which is the possibility of sharing information about the quality of a foraging area. Sharing information in a patch-foraging scenario gives each group member an opportunity to make a more accurate estimate of the quality of the patch. In this paper we present a mathematical model in which we study the effect of group size on patch-leaving policy and per capita intake rate. In the model, group members share information equally in a random search for food. Food is distributed in patches according to a negative binomial distribution. A prediction from our model is that, the larger the group, the earlier each group member should leave the current patch. We also find that the benefit from enhanced exchange of information does not exceed the cost of sharing food with group members. The per capita intake rate decreases as the group size increases. Therefore, animals should only form groups when other factors outweigh the costs, which is easiest to achieve when the travelling time is short. PMID:12816651

Sernland, Emma; Olsson, Ola; Holmgren, Noél M A

2003-01-01

367

Genetically-based variation between two spider populations in foraging behavior  

Microsoft Academic Search

Optimal foraging theory is based on the assumption that at least some aspects of foraging behavior are genetically determined (Pyke et al. 1977; Kamil and Sargent 1980; Pyke 1984). Nonetheless, very few studies have examined the role of genetics in foraging behavior. Here, we report on geographical differences in the foraging behavior of a spider (Agelenopsis aperta) and investigate whether

Ann V. Hedrick; Susan E. Riechert

1989-01-01

368

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

369

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

370

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

371

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

372

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

373

Differential root morphology response to no versus high phosphorus, in three hydroponically grown forage chicory cultivars  

Technology Transfer Automated Retrieval System (TEKTRAN)

Forage chicory is a productive forage resource for eastern North America; however, many soils in the region are acidic and deficient in P and might restrict the widespread use of forage chicory. There is no published information on response of forage chicory to P, or P acquisition strategies for mo...

374

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

375

FORAGE YIELD AND QUALITY OF TWELVE RED AND WHITE HARD WINTER WHEAT VARIETIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Winter wheat pasture provides economical, high-quality forage for livestock during a time few other grazable forages are available. Despite increased use of white wheat little is known about the forage. This experiment examined forage yield and quality of six hard red (2137, Jagalene, Jagger, OK101,...

376

Simulation of sandsage-bluestem forage growth under varying stocking rates  

Technology Transfer Automated Retrieval System (TEKTRAN)

The effect of stocking rate on forage growth has attracted a great deal of research attention in forage science. Findings show that forage growth may be affected by stocking rate and there is the consensus that high stocking rates lead to soil compaction, which could also in turn affect forage growt...

377

The use of waggle dance information by honey bees throughout their foraging careers  

Microsoft Academic Search

We studied the extent to which worker honey bees acquire information from waggle dances throughout their careers as foragers. Small groups of foragers were monitored from time of orientation flights to time of death and all in-hive behaviors relating to foraging were recorded. In the context of a novice forager finding her first food source, 60% of the bees relied,

Jacobus C. Biesmeijer; Thomas D. Seeley

2005-01-01

378

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

379

Foraging behavior delays mechanically-stimulated escape responses in fish.  

PubMed

Foraging and the evasion of predators are fundamental for the survival of organisms, but they impose contrasting demands that can influence performance in each behavior. Previous studies suggested that foraging organisms may experience decreased vigilance to attacks by predators; however, little is known about the effect of foraging on escape performance with respect to the kinematics and the timing of the response. This study tested the hypothesis that engaging in foraging activities affected escape performance by comparing fast-start escape responses of silver-spotted sculpins Blepsias cirrhosus under three conditions: (1) control (no foraging involved), (2) while targeting prey, and (3) immediately after capture of prey. Escape response variables (non-locomotor and locomotor) were analyzed from high-speed videos. Responsiveness was lower immediately after capturing a prey item compared with the other two treatments, and latency of performance was higher in the control treatment than in the other two. Locomotor variables such as maximum speed, maximum acceleration, and turning rates did not show statistical differences among the three groups. Our results demonstrate that foraging can negatively affect two fundamental components of the escape response: (1) responsiveness and (2) latency of escape, suggesting that engaging in foraging may decrease an individual's ability to successfully evade predators. PMID:23624863

Bohórquez-Herrera, Jimena; Kawano, Sandy M; Domenici, Paolo

2013-11-01

380

Production and transcriptional regulation of proanthocyanidin biosynthesis in forage legumes.  

PubMed

Proanthocyanidins (PA), also known as condensed tannins, contribute to important forage legumes traits including disease resistance and forage quality. PA in forage plants has both positive and negative effects on feed digestibility and animal performance. The analytical methods and their applicability in measuring the contents of PA in forage plants are essential to studies on their nutritional effects. In spite of important breakthroughs in our understanding of the PA biosynthesis, important questions still remain to be answered such as the PA polymerization and transport. Recent advances in the understanding of transcription factor-mediated gene regulation mechanisms in anthocyanin and PA biosynthetic pathway in model plants suggest new approaches for the metabolic engineering of PA in forage plants. The present review will attempt to present the state-of-the-art of research in these areas and provide an update on the production and metabolic engineering of PA in forage plants. We hope that this will contribute to a better understanding of the ways in which PA production to manipulate the content of PA for beneficial effects in forage plants. PMID:25805345

Zhou, Meiliang; Wei, Li; Sun, Zhanmin; Gao, Lihua; Meng, Yu; Tang, Yixiong; Wu, Yanmin

2015-05-01

381

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

382

Foraging activity is reduced in a mouse model of depression.  

PubMed

Depression interferes with the human ability to make decisions. Multiple criteria have been adopted for the diagnosis of depression in humans, but no clear indicators are available in animal models to reflect the depressive mood, involving higher cognitive functions. The act of foraging is a species-specific behaviour which is believed to involve the decision-making and higher cognitive functions. We previously established a method to detect the foraging behaviour of rodents, in which our results demonstrated that NMDA and dopamine receptors were involved. Conversely, increased NMDA receptors and reduced dopamine have been reported in depression model rodents. However, we hypothesise that foraging activities may also be impaired in depression. To test the theory, we successfully established a mouse model of depression using the chronic unpredictable mild stress (CUMS) paradigm. Most interestingly, the food foraging activity of mice after CUMS was significantly reduced. In addition, the treatment of anti-depressant fluoxetine reversed most depressive symptoms and reduced glial fibrillary associated protein (GFAP) expression in the hippocampus, but was less effective in the reduction of foraging activities. However, clozapine reversed all symptoms of CUMS-exposed mice including reduction of GFAP expression in the hippocampus and impaired foraging activity. Our findings of GFAP expression as a marker to validate the CUMS protocol provide further validation of our hypothesis, that the reduced food foraging is probably a new behavioural finding of depression in which the serotoninergic system could not be singly involved. Our study suggests that NMDA receptors, serotoninergic and dopaminergic systems are differentially involved in these food foraging behaviours. Our data suggest that the foraging test in rodents can be a useful tool to assess the ability of decision-making in depression. PMID:23873577

Yang, C R; Zhang, Z G; Bai, Y Y; Zhou, H Fiona; Zhou, L; Ruan, C S; Li, F; Li, C Q; Zheng, H Y; Shen, L J; Zhou, X F

2014-04-01

383

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

384

Transformation of forage legumes using Agrobacterium tumefaciens.  

PubMed

Galls were induced in six species of forage legumes following inoculation with wild-type strains of A. tumefaciens. The plant species was more influential than the bacterial strain in determining the type of tumour produced. Inoculation of Medicago sativa resulted in small, disorganised tumours. The three Trifolium species, T. repens, T. hybridum and T. pratense, formed galls which tended to produce roots and both Onobrychis viciifolia and Lotus corniculatus produced teratomatous galls. The shoots elongated in the latter species only. In L. corniculatus, tissues that were infected by five bacterial strains were capable of shoot regeneration when cultured on a hormone-free medium. The transformed nature of these shoots was confirmed by their failure to root, the production of callus from leaves cultured on hormone-free medium and the presence of opines. PMID:24247771

Webb, K J

1986-04-01

385

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

386

Seabird and Forage Fish Research in Alaska  

NSDL National Science Digital Library

The US Geological Survey (USGS)'s Alaska Biological Science Center (ABSC) conducts research in a number of areas, including this research on seabirds and forage fish in Alaska. Organized by topic, the site includes general information on marine animals and ecosystems in Alaska, specific information on ABSC seabird and fish projects (including some methods and results), and several informal 'sketches' of participating scientists. Although of particular interest to the research community, the site simultaneously serves as an excellent example of how scientists study complex ecosystems. By clicking on each "What we learned" icon, viewers may access results of specific projects and explanations of how those results tie into "the bigger picture." Further information on the Alaska Biological Science Center is provided at the ABSC homepage.

387

Stature in Holocene foragers of North India.  

PubMed

The Ganga Plain of North India provides an archaeological and skeletal record of semi-nomadic Holocene foragers in association with an aceramic Mesolithic culture. Prior estimates of stature for Mesolithic Lake Cultures (MLC) used inappropriate equations from an American White reference group and need revision. Attention is given to intralimb body proportions and geo-climatic provenance of MLC series in considering the most suitable reference population. Regression equations from ancient Egyptians are used in reconstructing stature for MLC skeletal series from Damdama (DDM), Mahadaha (MDH), and Sarai Nahar Rai (SNR). Mean stature is estimated at between 174 (MDH) and 178 cm (DDM and SNR) for males, and between 163 cm (MDH) and 179 cm (SNR) for females. Stature estimates based on ancient Egyptian equations are significantly shorter (from 3.5 to 7.1 cm shorter in males; from 3.2 to 7.5 cm shorter in females) than estimates using the American White reference group. Revised stature estimates from tibia length and from femur?+?tibia more accurately estimate MLC stature for two reasons: a) these elements are highly correlated with stature and have lower standard estimates of error, and b) uncertainty regarding methods of measuring tibia length is avoided. When compared with Holocene samples of native Americans and Mesolithic Europeans, MLC series from North India are tall. This aspect of their biological variation confirms earlier assessments and results from the synergistic influence of balanced nutrition from broad-spectrum foraging, body-proportions adapted to a seasonally hot and arid climate, and the functional demands of a mobile, semi-nomadic life-style. PMID:24374782

Lukacs, John R; Pal, J N; Nelson, Greg C

2014-03-01

388

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...

389

Adélie Penguin Foraging Location Predicted by Tidal Regime Switching  

PubMed Central

Penguin foraging and breeding success depend on broad-scale environmental and local-scale hydrographic features of their habitat. We investigated the effect of local tidal currents on a population of Adélie penguins on Humble Is., Antarctica. We used satellite-tagged penguins, an autonomous underwater vehicle, and historical tidal records to model of penguin foraging locations over ten seasons. The bearing of tidal currents did not oscillate daily, but rather between diurnal and semidiurnal tidal regimes. Adélie penguins foraging locations changed in response to tidal regime switching, and not to daily tidal patterns. The hydrography and foraging patterns of Adélie penguins during these switching tidal regimes suggest that they are responding to changing prey availability, as they are concentrated and dispersed in nearby Palmer Deep by variable tidal forcing on weekly timescales, providing a link between local currents and the ecology of this predator. PMID:23383091

Oliver, Matthew J.; Irwin, Andrew; Moline, Mark A.; Fraser, William; Patterson, Donna; Schofield, Oscar; Kohut, Josh

2013-01-01

390

Original article On optimal nectar foraging by some tropical bees  

E-print Network

Center, 2000, East Allen Road, Tucson, AZ 85719; 4 Department of Zoology, University of Maryland, College / optimal foraging / pollination INTRODUCTION An intringuing question was posed by Eick- wort and Ginsberg

Paris-Sud XI, Université de

391

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...

392

Spatial and temporal patterns of resource heterogeneity and foraging behavior  

E-print Network

to target resources. I studied Black-chinned (Archilochus alexandri) and Buff-bellied Hummingbirds (Amazilia yucatanensis) foraging at Turk's Cap (Malvaviscus arboreus var. drummondii) and artificial flowers in southern Texas. l quantified the distribution...

Baum, Kristen Anne

1999-01-01

393

Foraging behaviour and diet selection in domestic herbivores  

E-print Network

Review Foraging behaviour and diet selection in domestic herbivores Sophie Prache lain J. Gordon; Comportement d'ingestion et choix alimentaires au pâturage chez les herbivores domestiques. Le comportement d

Boyer, Edmond

394

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...

395

Dimorphic foraging behaviors and the evolution of hominid hunting.  

PubMed

In contemporary foraging societies men typically hunt more than women. This observation has played an important role in many reconstructions of hominid evolution. The gender difference in human hunting, likely a product of both ecological and cultural factors, is mirrored by a similar sex difference among nonhuman primates. Existing explanations of such primate behavioral dimorphism are augmented by the recognition of an additional factor that may contribute to differences between males and females in the value of meat. Episodic female immunosuppression is a normal part of reproduction. Because meat is a source of pathogens, females can be expected to exhibit less constant attraction to meat. Sexual dimorphism in the attraction to meat may then contribute to dimorphic foraging specializations, a divergence that is likely augmented by the differential value of insectivory across the sexes. With the rise of cultural transmission of foraging knowledge, dimorphic foraging behaviors would have been reinforced, creating a more comprehensive gender-based division of labor. PMID:12680308

Fessler, Daniel M T

2002-01-01

396

Photo Guide to Forage Supplies on Texas Rangelands  

E-print Network

Accurately determining stocking rate is important to successful range management. This publication helps ranchers to estimate pounds of forage per acre, improving the consistency and accuracy of their stocking rate determinations....

Hanselka, C. Wayne; McGinty, Allan

2006-06-21

397

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....

398

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, ...

399

SITE TECHNOLOGY CAPSULE: DYNAPHORE, INC., FORAGER¿ SPONGE TECHNOLOGY  

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. The technology treats contaminated groundwater, surface waters, and process waters by absorbi...

400

SITE TECHNOLOGY CAPSULE: DYNAPHORE, INC., FORAGER SPONGE TECHNOLOGY  

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 waters and porous waters by absorbing d...

401

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...

402

Movements of foraging king penguins through marine mesoscale eddies  

PubMed Central

Despite increasing evidence that marine predators associate with mesoscale eddies, how these marine features influence foraging movements is still unclear. This study investigates the relationship of at-sea movements of king penguins to mesoscale eddies using oceanographic remote sensing and movement data from 43 individual trips over 4 years. Simultaneous satellite measurements provided information on gradients of sea surface temperature and currents associated with eddies determined from altimetry. Penguins tended to swim rapidly with currents as they travelled towards foraging zones. Swimming speed indicative of foraging occurred within mesoscale fronts and strong currents associated with eddies at the Polar Front. These results demonstrate the importance of mesoscale eddies in directing foraging efforts to allow predators to rapidly get to rich areas where high concentrations of prey are likely to be encountered. When returning to the colony to relieve the incubating partner or to feed the chick, the birds followed a direct and rapid path, seemingly ignoring currents. PMID:17669726

Cotté, Cédric; Park, Young-Hyang; Guinet, Christophe; Bost, Charles-André

2007-01-01

403

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, ...

404

Diet, nutrition and forage requirements of javelina in South Texas  

E-print Network

DIET, NUTRITION AND FORAGE REQUIREMENTS OF JAVELINA IN SOUTH TEXAS A Thesis by JAMES FRANCIS GALLAGHER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... December 1981 Major Subject: Wildlife and Fisheries Sciences DIET, NUTRITION AND FORAGE REQUIREMENTS OF JAVELINA IN SOUTH TEXAS A Thesis by James Francis Gallagher Approved as to style and content by: Chairman o Committee) ( Member) 7 (Member) er...

Gallagher, James Francis

1981-01-01

405

GROWTH AND MANAGEMENT OF SORGHUMS FOR FORAGE PRODUCTION  

Microsoft Academic Search

Forage sorghums can be grown in a wide variety of soil types, pH levels from 5.5 to 8.5, and varying moisture levels. Forage sorghums use approximately 40-50% less water than corn to produce the same dry matter. New genetic traits regulating photoperiod sensitivity, delayed maturity, brown midrib, and increased tillering and recovery are impacting quality. Increased palatability and digestibility has

F. R. Miller; J. A. Stroup

406

Southern rockhopper penguin Eudyptes chrysocome chrysocome foraging at Possession Island  

Microsoft Academic Search

The foraging ecology of rockhopper penguins was studied at Possession Island, southern Indian Ocean, by counting the number\\u000a of birds departing from and arriving at colonies over the course of the day and by equipping three birds with time\\/depth loggers,\\u000a one of which was recovered having recorded a total of 12 days foraging activity. Both the counts and the results

Rory P. Wilson; Charles A. Bost; Klemens Pütz; Jean-Benoît Charrassin; Boris M. Culik; D. Adelung

1997-01-01

407

Potential digestibilities and digestion kinetics of forage cell wall components  

E-print Network

, 12, 18, 24, 48 and 72 hrs. with common source innocula. Forage and in sitz'o residue composition was analyzed for neutral detergent fiber (NDF); easily hydrolyzable hemicellulose (EHH); difficultly hydrolyzable hemicellulose (DHH); cellulose (C...); and lignin (L) . Between species comparison of forage composition indicated a higher percent neutral detergent extract (cell solubles) and cellulose for Sorghums. The coefficients of digestibility for all fractions were higher for the Sorghums...

Tauskey, William Henry

1973-01-01

408

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

409

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

410

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

411

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

412

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

413

Social calls predict foraging success in big brown bats.  

PubMed

Animals foraging in the dark are engaged simultaneously in prey pursuit, collision avoidance, and interactions with conspecifics, making efficient nonvisual communication essential. A variety of birds and mammals emit food-associated calls that inform, attract, or repel conspecifics (e.g.,). Big brown bats (Eptesicus fuscus) are insectivorous aerial hawkers that may forage near conspecifics and are known to emit social calls (e.g.,). Calls recorded in a foraging setting might attract (e.g.,) or repel conspecifics and could denote territoriality or food claiming. Here, we provide evidence that the "frequency-modulated bout" (FMB), a social call emitted only by male bats (exclusively in a foraging context), is used to claim food and is individually distinct. Bats were studied individually and in pairs in a flight room equipped with synchronized high-speed stereo video and audio recording equipment while sex and experience with a foraging task were experimentally manipulated. Male bats emitting the FMB showed greater success in capturing prey. Following FMB emission, interbat distance, diverging flight, and the other bat's distance to the prey each increased. These findings highlight the importance and utility of vocal communication for a nocturnal animal mediating interactions with conspecifics in a fast-paced foraging setting. PMID:24684936

Wright, Genevieve Spanjer; Chiu, Chen; Xian, Wei; Wilkinson, Gerald S; Moss, Cynthia F

2014-04-14

414

Chaos-order transition in foraging behavior of ants.  

PubMed

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

2014-06-10

415

Social Calls Predict Foraging Success in Big Brown Bats  

PubMed Central

Animals foraging in the dark are simultaneously engaged in prey pursuit, collision avoidance and interactions with conspecifics, making efficient, non-visual communication essential. A variety of birds and mammals emit food-associated calls that inform, attract, or repel conspecifics [e.g., 1]. Big brown bats (Eptesicus fuscus) are insectivorous aerial hawkers that may forage near conspecifics and are known to emit social calls [e.g., 2, 3, 4, 5]. Calls recorded in a foraging setting might attract [e.g., 6] or repel conspecifics [7] and could denote territoriality or food-claiming. Here, we provide evidence that a social call emitted only by male bats, exclusively in a foraging context [5], the “frequency-modulated bout” (FMB), is used to claim food and is individually distinct. Bats were studied individually and in pairs in a flight room equipped with synchronized high-speed stereo video and audio recording equipment, while sex and experience with a foraging task were experimentally manipulated. Male bats emitting the FMB showed greater success in capturing prey. Following FMB emission, inter-bat distance, diverging flight, and the other bat’s distance to the prey each increased. These findings highlight the importance and utility of vocal communication for a nocturnal animal mediating interactions with conspecifics in a fast-paced foraging setting. PMID:24684936

Wright, Genevieve Spanjer; Chiu, Chen; Xian, Wei; Wilkinson, Gerald S.; Moss, Cynthia F.

2014-01-01

416

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

417

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

418

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

419

Response of the residential piscivorous fish community to introduction of a new predator type in a mesotrophic lake  

Microsoft Academic Search

Although the effects of introduced predators on prey populations in aquatic ecosystems have been studied frequently, less is known about the interactions between predators. We performed a whole-lake experiment by stocking a non-native top predator (pikeperch (Sander lucioperca)) to two residential piscivores (Eurasian perch (Perca fluviatilis) and northern pike (Esox lucius)). By analyzing spatial distribution, diet composition, growth, and consump-

Torsten Schulze; Ulrich Baade; Hendrik Dörner; Reiner Eckmann; Susanne S. Haertel-Borer; Franz Hölker; Thomas Mehner

2006-01-01

420

Oviduct Insertion of Radio Transmitters as a Means of Locating Northern Pike Spawning Habitat  

Microsoft Academic Search

I inserted radio transmitters into the oviducts of northern pike Esox lucius in an attempt to find their spawning grounds. Oviduct insertion of miniature radio transmitters was quick and easy. I hoped that transmitters would be expelled with the eggs to aid in identifying critical habitat used for egg deposition. Ten transmitters were implanted in the egg masses of female

Rodney B. Pierce

2004-01-01

421

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).  ...

422

Ranking Predatory Threats by Nonnative Fishes in the Yampa River, Colorado, via Bioenergetics Modeling  

Microsoft Academic Search

Because of its relatively natural hydrograph, the Yampa River, Colorado, is considered the crown jewel of native fish habitat in the upper basin of the Colorado River and has supported a relatively intact native fish assemblage. Nonnative fishes are thought to pose the greatest threat to native fishes in this system. Removal programs for nonnative northern pike Esox lucius and

Brett M. Johnson; Patrick J. Martinez; John A. Hawkins; Kevin R. Bestgen

2008-01-01

423

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

424

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

425

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

426

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

427

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

428

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

429

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

430

Electrofishing Catchability of Walleyes, Largemouth Bass, Smallmouth Bass, Northern Pike, and Muskellunge in Wisconsin Lakes  

Microsoft Academic Search

We sought to determine whether electrofishing catchability was density dependent and varied with physical and biological factors for walleyes Sander vitreus, largemouth bass Micropterus salmoides, smallmouth bass M. dolomieu, northern pike Esox lucius, and muskellunge E. masquinongy in Wisconsin lakes. Electrofishing catch rate (number of fish caught per shoreline mile) was linearly related to population density (number of fish per

Casey W. Schoenebeck; Michael J. Hansen

2005-01-01

431

Factors Affecting Growth of Northern Pike in Small Northern Wisconsin Lakes  

Microsoft Academic Search

Fish assemblages that include northern pike Esox lucius as a dominant predator were sampled in 19 small (<120 ha) northern Wisconsin lakes. The purpose of this sampling was to describe northern pike population characteristics and identify factors affecting growth rates. Fish assemblages in these lakes were dominated by centrarchids, primarily bluegill Lepomis macrochirus, and small fusiform species such as yellow

Terry L. Margenau; Paul W. Rasmussen; Jeffrey M. Kampa

1998-01-01

432

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...

433

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...

434

Population Characteristics and Ecological Role of Northern Pike in Shallow Natural Lakes in Nebraska  

Microsoft Academic Search

Northern pike Esox lucius were sampled in Nebraska's Sandhill lakes during 1998 and 1999 to determine population characteristics and their influence on the fish community in these shallow, warm lakes at the southwestern edge of this species' natural range. Density-de- pendent growth, size structure, and condition were not evident in the northern pike populations sampled. Relative abundance of largemouth bass

Craig P. Paukert; David W. Willis

2003-01-01

435

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

436

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

437

Size Selectivity, Injury, Handling Time, and Determinants of Initial Hooking Mortality in Recreational Angling for Northern Pike: The Influence of Type and Size of Bait  

Microsoft Academic Search

We examined the relationship between bait and lure size and type and body size, injury, and handling time for northern pike Esox lucius, an important recreational fisheries resource in much of North America and Europe. Bait type and size were significantly related to the size of fish captured and hooking location. Hooking in critical locations (i.e., gills, gullet) was more

Robert Arlinghaus; Thomas Klefoth; Alexander Kobler; Steven J. Cooke

2008-01-01

438

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

439

Using Bioenergetics Modeling to Estimate Consumption of Native Juvenile Salmonids by Nonnative Northern Pike in the Upper Flathead River System, Montana  

Microsoft Academic Search

Introductions of nonnative northern pike Esox lucius have created recreational fisheries in many waters in the United States and Canada, yet many studies have shown that introduced northern pike may alter the composition and structure of fish communities through predation. We estimated the abundance of nonnative northern pike (2002–2003) and applied food habits data (1999–2003) to estimate their annual consumption

Clint C. Muhlfeld; David H. Bennett; R. Kirk Steinhorst; Brian Marotz; Matthew Boyer

2008-01-01

440

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

441

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

442

Reactions of Gammarus lacustris to Chemical Stimuli from Natural Predators and Injured Conspecifics  

Microsoft Academic Search

We exposed the freshwater amphipod Gammarus lacustris, to chemical stimuli from injured conspecifics and to chemical stimuli from two types of natural predators: dragonfly larvae (Aeshna eremita) and northern pike (Esox lucius). Exposure to all three stimuli caused G. lacustris to reduce significantly its level of activity relative to activity recorded in response to a distilled water control. The similarity

Karen Wudkevich; Brian D. Wisenden; Douglas P. Chivers; R. Jan F. Smith

1997-01-01

443

The role of olfaction in chemosensory-based predator recognition in the fathead minnow, Pimephales promelas  

Microsoft Academic Search

Solitary fathead minnows (Pimephales promelas) were rendered anosmic and exposed to chemical stimuli from a predatory northern pike (Esox lucius) to determine the role of olfaction in the minnow's ability to recognize predators on the basis of chemical stimuli. Anosmic fish did not respond to the pike stimuli with a typical fright reaction, while control fish, with intact olfactory receptors,

Douglas P. Chivers; R. Jan F. Smith

1993-01-01

444

Journal of Chemical Ecology, Vol. 23, No. 1, 1997 LEARNED RECOGNITION OF PREDATION RISK BY  

E-print Network

minnows (Pimephales promelas). The response to injured fathead minnows was not a general response). European minnows (Phoxinus phoxinus), fathead minnows (Pimephales promelas), and brook stick- leback promelas, northern pike, Esox lucius. *To whom correspondence should be addressed at Center for Ecology

Wisenden, Brian D.

445

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

446

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

447

Mercury evolution (1978–1988) in fishes of the La Grande hydroelectric complex, Quebec, Canada  

Microsoft Academic Search

From 1978 to 1988, the evolution of the Hg content of fish has been monitored in the areas affected by the La Grande hydroelectric\\u000a complex. Four fish species were considered: two non piscivorous, lake whitefish (Coregonus clupeaformis) and longnose sucker (Catostomus catostomus), and two piscivorous, northern pike (Esox lucius) and walleye (Stizostedion vitreum). The evolution of Hg concentrations in time

R. Verdon; D. Brouard; C. Demers; R. Lalumiere; M. Laperle; R. Schetagne

1991-01-01

448

The relationship between piscivory and growth of white sucker ( Catostomus commersoni ) and yellow perch ( Perca flavescens ) in headwater lakes of the Canadian Shield  

Microsoft Academic Search

We used data from a survey of 36 headwater lakes of the Canadian Shield to investigate the relationship between piscivory and growth, abundance, and longevity of white sucker (Catostomus commersoni) and yellow perch (Perca flavescens). The occurrence of northern pike (Esox lucius) and walleye (Sander vitreus) explained variations in the abundance of both white sucker and yellow perch, suggesting strong

Andrea Bertolo; Pierre Magnan

2005-01-01

449

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

E-print Network

and Largemouth Bass Scott D. Gurtina· Michael L. Brown, and Charles G. Scalet Department of Wildlife and October 1995.315 largemouth bass (Micropterus salmoides) and 170 northern pike (Esox lucius) were captured bass at large from 355 to 395 days. Tag retention was 88% for largemouth bass tagged and recaptured

450

Nectar robbing, forager efficiency and seed set: Bumblebees foraging on the self incompatible plant Linaria vulgaris (Scrophulariaceae)  

E-print Network

of robbed flowers and in pods of flowers that were artificially protected against robbing. However, more legitimate foragers are present in the population, and that seed predation and seed abortion after

451

Performance and economic analyses of year-round forage systems for forage-fed beef production in the Gulf Coast.  

PubMed

On a global scale, most beef is produced from grazing pastures or rangelands. Certain limitations exist, however, such as not having adequate animal rates of gain for marbling and availability of adequate forage nutritional value and quantity for constant animal weight gains. In the last 20 yr, there has been an increased interest in forage-fed beef for multiple reasons (health related, environmental concerns, and welfare issues). Starting on June 5, 13, 14, and 8 in 4 consecutive yr, 54 steers (initial BW=259±5.6 kg; average of 9 mo of age) were randomly allotted to 3 yr-round forage systems. Each system occupied 6 ha/replicate and had the same stocking rate. System 1 had annual ryegrass (Lolium multiflorum) for winter grazing and bermudagrass (Cynodon dactylon) for summer grazing; while Systems 2 and 3 added rye and a clover mix to the ryegrass and diversified the use of pastures in the fall (dallisgrass [Paspalum dilatatum] and clovers [Trifolium spp.]). System 3 added the use of annual summer forages. During their respective growing season for each forage or forage mix, mass and height did not limit animal performance; however, there was a sampling date effect (P<0.05) for nutritive value variables since it decreased as forages became mature. The ADG observed (0.44 kg) for all systems (P=0.78) during summer was lower than expected and might have been limited by the observed temperature as well as forage nutritive value. Systems 1 and 2 had more grazing days (P=0.03) during summer (155 and 146 d, respectively) compared to System 3 (132 d) due to the greater pasture area of bermudagrass in those systems. Steers in System 3 were fed more hay for a longer period of time (P<0.05) than on the other 2 systems. System 1 and 2 produced more hay per hectare than System 3 (P<0.05). No differences (P>0.05) were detected between systems in ADG year round, during the winter season, or carcass characteristics. Return over total direct costs and total specified expenses were greater for Systems 1 and 2, while System 3 was the lowest. Hay making and bale sales played a major role in explaining the economic results of this study. Where possible, year-round forage systems are a viable alternative for forage-fed beef production; however, the low gains during summer and forage availability during the transition period when hay is necessary deserve further research to find alternatives to improve productivity during those times of the year. PMID:25367513

Scaglia, G; Rodriguez, J; Gillespie, J; Bhandari, B; Wang, J J; McMillin, K W

2014-12-01

452

Comparative digestibility by cattle versus sheep: effect of forage quality.  

PubMed

The objective was to determine the effect of forage quality on apparent total tract digestibility and ruminal fermentation in cattle versus sheep. Five yearling English crossbred (Hereford × Angus) steers (440.4 ± 35.6 kg of initial BW) and 5 yearling whiteface (Rambouillet × Columbia × Debouillet) wethers (44.4 ± 4.6 kg of initial BW), each fitted with a ruminal cannula, were randomly assigned to 1 of 3 forage sources within ruminant specie, and the study was conducted over 3 periods. For forage source, both animal and period served as the blocking factor with all forage sources represented once within each animal and all forage sources represented at least once within each period. The treatment structure was arranged in a 2 × 3 factorial with ruminant species (2) and forage source (3) as the factors. Forage sources were 1) alfalfa hay (Medicago sativa; 17.5% CP and 34.1% NDF, DM basis), 2) warm-season grass hay mix (Bothriochloa ischaemum and Cynodon dactylon; 7.3% CP and 74.7% NDF, DM basis), and 3) lovegrass hay (Eragrostis curvula; 2.5% CP and 81.9% NDF, DM basis). As a percent of BW, steers and wethers consumed similar (P ? 0.06) amounts of forage, and intake was more influenced by forage quality (P < 0.001) than ruminant species (P = 0.35). When expressed per unit of metabolic BW, cattle consumed more (P < 0.001) DM, NDF, and N than sheep. Apparent total tract digestibility was similar among steers and wethers when alfalfa or grass hay was fed, but decreased to a greater extent in wethers when low-quality lovegrass hay was fed (ruminant species × diet interaction, P ? 0.01). Rate (%/h) of ruminal NDF disappearance was greater (P = 0.02) for alfalfa and grass hay than lovegrass, but was not influenced (P = 0.12) by ruminant species. In addition, ruminal DM fill was influenced more (P < 0.01) by forage than by ruminant species (P = 0.07). Steers and wethers had greater (P < 0.01) DM fill from grass hay and lovegrass hay than alfalfa before and 5 h after feeding. Ruminal VFA were generally not influenced (P ? 0.06) by ruminant specie. Results suggest that apparent total tract digestibilities are more similar among ruminant species when moderate- to high-quality forages are evaluated. However, sheep are not an adequate model for cattle when low-quality forages are compared because cattle digest low-quality forages to a greater extent than sheep. Expressing digestibility as digestible intake per unit of BW allows for a wider range of forage qualities to be compared when substituting sheep for cattle. PMID:24663196

Soto-Navarro, S A; Lopez, R; Sankey, C; Capitan, B M; Holland, B P; Balstad, L A; Krehbiel, C R

2014-04-01

453

Simultaneous brightness contrast of foraging Papilio butterflies  

PubMed Central

This study focuses on the sense of brightness in the foraging Japanese yellow swallowtail butterfly, Papilio xuthus. We presented two red discs of different intensity on a grey background to butterflies, and trained them to select one of the discs. They were successfully trained to select either a high intensity or a low intensity disc. The trained butterflies were tested on their ability to perceive brightness in two different protocols: (i) two orange discs of different intensity presented on the same intensity grey background and (ii) two orange discs of the same intensity separately presented on a grey background that was either higher or lower in intensity than the training background. The butterflies trained to high intensity red selected the orange disc of high intensity in protocol 1, and the disc on the background of low intensity grey in protocol 2. We obtained similar results in another set of experiments with purple discs instead of orange discs. The choices of the butterflies trained to low intensity red were opposite to those just described. Taken together, we conclude that Papilio has the ability to learn brightness and darkness of targets independent of colour, and that they have the so-called simultaneous brightness contrast. PMID:22179808

Kinoshita, Michiyo; Takahashi, Yuki; Arikawa, Kentaro

2012-01-01

454

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

PubMed

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

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

2014-01-01

455

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

456

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

USGS Publications Warehouse

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.

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

457

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

458

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

459

Evidence for foraging -site fidelity and individual foraging behavior of pelagic cormorants rearing chicks in the gulf of Alaska  

USGS Publications Warehouse

The Pelagic Cormorant (Phalacrocorax pelagicus) is the most widespread cormorant in the North Pacific, but little is known about its foraging and diving behavior. However, knowledge of seabirds' foraging behavior is important to understanding their function in the marine environment. In 2006, using GPS dataloggers, we studied the foraging behavior of 14 male Pelagic Cormorants rearing chicks on Middleton Island, Alaska. For foraging, the birds had high fidelity to a small area 8 km north of the colony. Within that area, the cormorants' diving activity was of two distinct kinds-near-surface dives (1-6 m) and benthic dives (28-33 m). Individuals were consistent in the depths of their dives, either mostly shallow or mostly deep. Few showed no depth preference. Dive duration, time at maximum depth, and pauses at the water surface between consecutive dives were shorter for shallow dives than for deep dives. The cormorants made dives of both types throughout the day, but the frequency of deep dives increased toward evening. Maximum foraging range was 9 km; maximum total distance traveled per trip was 43.4 km. Trip durations ranged from 0.3 to 7.7 hr. Maximum depth of a dive was 42.2 m, and duration of dives ranged from 4 to 120 sec. We found that Pelagic Cormorants at Middleton Island were faithful to one particular foraging area and individuals dived in distinct patterns. Distinct, specialized foraging behavior may be advantageous in reducing intra- and interspecific competition but may also render the species vulnerable to changing environmental conditions. Copyright ?? The Cooper Ornithological Society 2011.

Kotzerka, J.; Hatch, S.A.; Garthe, S.

2011-01-01

460

Trail geometry gives polarity to ant foraging networks.  

PubMed

Pheromone trails are used by many ants to guide foragers between nest and food. But how does a forager that has become displaced from a trail know which way to go on rejoining the trail? A laden forager, for example, should walk towards the nest. Polarized trails would enable ants to choose the appropriate direction, thereby saving time and reducing predation risk. However, previous research has found no evidence that ants can detect polarity from the pheromone trail alone. Pharaoh's ants (Monomorium pharaonis) produce elaborate trail networks throughout their foraging environment. Here we show that by using information from the geometry of trail bifurcations within this network, foragers joining a trail can adaptively reorientate themselves if they initially walk in the wrong direction. The frequency of correct reorientations is maximized when the trail bifurcation angle is approximately 60 degrees, as found in natural networks. These are the first data to demonstrate how ant trails can themselves provide polarity information. They also demonstrate previously unsuspected sophistication in the organization and information content of networks in insect societies. PMID:15602563

Jackson, Duncan E; Holcombe, Mike; Ratnieks, Francis L W

2004-12-16

461

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

462

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

463

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) visiting naturally occurring flowers of Mimulus guttatus (Scrophulariaceae). The results indicate that A. mellifera preferentially selects larger M. guttatus flowers in their foraging bouts. Since differences

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

464

Introduced forage species herbage dry matter production and chemical composition at two  

E-print Network

Introduced forage species herbage dry matter production and chemical composition at two moist of introduced forage species whose seed were provided by ILCA's gene bank were evaluated for adaptation and dry

Paris-Sud XI, Université de

465

Phase transition between disordered and ordered foraging in Pharaoh's ants  

PubMed Central

The complex collective behavior seen in many insect societies strongly suggests that a minimum number of workers are required for these societies to function effectively. Here we investigated the transition between disordered and ordered foraging in the Pharaoh's ant. We show that small colonies forage in a disorganized manner, with a transition to organized pheromone-based foraging in larger colonies. We also show that when food sources are difficult to locate through independent searching, this transition is first-order and exhibits hysteresis, comparable to a first-order phase transition found in many physical systems. To our knowledge, this is the first experimental evidence of a behavioral phase transition between a maladaptive (disorganized) and an adaptive (organized) state. PMID:11493681

Beekman, Madeleine; Sumpter, David J. T.; Ratnieks, Francis L. W.

2001-01-01

466

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

467

Neuronal mechanism for acute mechanosensitivity in tactile-foraging waterfowl  

PubMed Central

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.

2014-01-01

468

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

469

Evolution of Optimum Foraging Distributions in Two Dimensions  

NASA Astrophysics Data System (ADS)

In the pursuit of optimally efficient foraging, preferred distributions of movement characteristics have been shown to exist for many types of animals and environments. Specifically, planktonic organisms such as Daphnia use exponential distributions of turning angles, ?, in a ``hop, pause, turn by angle ?, hop'' random walk-type sequence of movement when traversing experimentally prepared feeding solutions consisting of freeze dried Spirolina and water. We investigate the evolution of such random walks in a two-dimensional foraging model. In this model, agents traverse a feeding patch of finite size and for a finite amount of time using hop lengths and turning angles chosen randomly from inherited distributions. Distributions evolve as the choices made by the most efficient forager of one generation influence the distributions available to the succeeding generation. Preliminary results show that initially uniform turning angle distributions evolve to explicit exponential distributions after thousands of generations, consistent with the experimental observations described above.

Dees, Nathan; Bahar, Sonya; Moss, Frank

2008-03-01

470

Optimal foraging for specific nutrients in predatory beetles  

PubMed Central

Evolutionary theory predicts that animals should forage to maximize their fitness, which in predators is traditionally assumed equivalent to maximizing energy intake rather than balancing the intake of specific nutrients. We restricted female predatory ground beetles (Anchomenus dorsalis) to one of a range of diets varying in lipid and protein content, and showed that total egg production peaked at a target intake of both nutrients. Other beetles given a choice to feed from two diets differing only in protein and lipid composition selectively ingested nutrient combinations at this target intake. When restricted to nutritionally imbalanced diets, beetles balanced the over- and under-ingestion of lipid and protein around a nutrient composition that maximized egg production under those constrained circumstances. Selective foraging for specific nutrients in this predator thus maximizes its reproductive performance. Our findings have implications for predator foraging behaviour and in the structuring of ecological communities. PMID:22237910

Jensen, Kim; Mayntz, David; Toft, Søren; Clissold, Fiona J.; Hunt, John; Raubenheimer, David; Simpson, Stephen J.

2012-01-01

471

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

472

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

473

Individual foraging components of harvester ants: movement patterns and seed patch fidelity  

Microsoft Academic Search

Summary We investigated individual foraging components of the western harvester ant,Pogonomyrmex occidentalis, in the native seed background of a shrub-steppe environment. Our study identified factors affecting foraging movements and seed selection by individual ants. Some assumptions and predictions of central-place foraging theory and a correlated random walk were evaluated for individual foragers. Results showed that ant size was only weakly

T. O. Crist; J. A. MacMahon

1991-01-01

474

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

475

Does Foraging Behaviour Affect Female Mate Preferences and Pair Formation in Captive Zebra Finches?  

PubMed Central

Background Successful foraging is essential for survival and reproductive success. In many bird species, foraging is a learned behaviour. To cope with environmental change and survive periods in which regular foods are scarce, the ability to solve novel foraging problems by learning new foraging techniques can be crucial. Although females have been shown to prefer more efficient foragers, the effect of males' foraging techniques on female mate choice has never been studied. We tested whether females would prefer males showing the same learned foraging technique as they had been exposed to as juveniles, or whether females would prefer males that showed a complementary foraging technique. Methodology/Principal Findings We first trained juvenile male and female zebra finches (Taeniopygia guttata) to obtain a significant proportion of their food by one of two foraging techniques. We then tested whether females showed a preference for males with the same or the alternative technique. We found that neither a male's foraging technique nor his foraging performance affected the time females spent in his proximity in the mate-choice apparatus. We then released flocks of these finches into an aviary to investigate whether assortative pairing would be facilitated by birds taught the same technique exploiting the same habitat. Zebra finches trained as juveniles in a specific foraging technique maintained their foraging specialisation in the aviary as adults. However, pair formation and nest location were random with regard to foraging technique. Conclusions/Significance Our findings show that zebra finches can be successfully trained to be foraging specialists. However, the robust negative results of the conditions tested here suggest that learned foraging specializations do not affect mate choice or pair formation in our experimental context. PMID:21179514

Boogert, Neeltje J.; Bui, Cavina; Howarth, Krista; Giraldeau, Luc-Alain; Lefebvre, Louis

2010-01-01

476

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

477

Contrafreeloading in grizzly bears: implications for captive foraging enrichment.  

PubMed

Although traditional feeding regimens for captive animals were focused on meeting physiological needs to assure good health, more recently emphasis has also been placed on non-nutritive aspects of feeding. The provision of foraging materials to diversify feeding behavior is a common practice in zoos but selective consumption of foraging enrichment items over more balanced "chow" diets could lead to nutrient imbalance. One alternative is to provide balanced diets in a contrafreeloading paradigm. Contrafreeloading occurs when animals choose resources that require effort to exploit when identical resources are freely available. To investigate contrafreeloading and its potential as a theoretical foundation for foraging enrichment, we conducted two experiments with captive grizzly bears (Ursus arctos horribilis). In Experiment 1, bears were presented with five foraging choices simultaneously: apples, apples in ice, salmon, salmon in ice, and plain ice under two levels of food restriction. Two measures of contrafreeloading were considered: weight of earned food consumed and time spent working for earned food. More free than earned food was eaten, with only two bears consuming food extracted from ice, but all bears spent more time manipulating ice containing salmon or apples than plain ice regardless of level of food restriction. In Experiment 2, food-restricted bears were presented with three foraging choices simultaneously: apples, apples inside a box, and an empty box. Although they ate more free than earned food, five bears consumed food from boxes and all spent more time manipulating boxes containing apples than empty boxes. Our findings support the provision of contrafreeloading opportunities as a foraging enrichment strategy for captive wildlife. PMID:19816856

McGowan, Ragen T S; Robbins, Charles T; Alldredge, J Richard; Newberry, Ruth C

2010-01-01

478

Context dependence in foraging behaviour of Achillea millefolium.  

PubMed

Context-dependent foraging behaviour is acknowledged and well documented for a diversity of animals and conditions. The contextual determinants of plant foraging behaviour, however, are poorly understood. Plant roots encounter patchy distributions of nutrients and soil fungi. Both of these features affect root form and function, but how they interact to affect foraging behaviour is unknown. We extend the use of the marginal value theorem to make predictions about the foraging behaviour of roots, and test our predictions by manipulating soil resource distribution and inoculation by soil fungi. We measured plant movement as both distance roots travelled and time taken to grow through nutrient patches of varied quality. To do this, we grew Achillea millefolium in the centers of modified pots with a high-nutrient patch and a low-nutrient patch on either side of the plant (heterogeneous) or patch-free conditions (homogeneous). Fungal inoculation, but not resource distribution, altered the time it took roots to reach nutrient patches. When in nutrient patches, root growth decreased relative to homogeneous soils. However, this change in foraging behaviour was not contingent upon patch quality or fungal inoculation. Root system breadth was larger in homogeneous than in heterogeneous soils, until measures were influenced by pot edges. Overall, we find that root foraging behaviour is modified by resource heterogeneity but not fungal inoculation. We find support for predictions of the marginal value theorem that organisms travel faster through low-quality than through high-quality environments, with the caveat that roots respond to nutrient patches per se rather than the quality of those patches. PMID:22622873

Karst, Justine D; Belter, Pamela R; Bennett, Jonathan A; Cahill, James F

2012-12-01

479

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

480

Variation in predator foraging behavior changes predator-prey spatio-temporal dynamics  

Technology Transfer Automated Retrieval System (TEKTRAN)

1. Foraging underlies the ability of all animals to acquire essential resources and, thus, provides a critical link to understanding population dynamics. A key issue is how variation in foraging behavior affects foraging efficiency and predator-prey interactions in spatially-heterogeneous environmen...

481

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

482

Hydrocarbons emitted by waggle-dancing honey bees stimulate colony foraging activity by causing experienced  

E-print Network

Hydrocarbons emitted by waggle-dancing honey bees stimulate colony foraging activity by causing. INTRODUCTION The waggle dance is a pattern of movement performed by successful honey bee foragers within the nest to recruit colony mates to forage on a profitable food source. This honey bee "dance language

483

Foraging habitat use by wood storks nesting in the coastal zone of Georgia, USA  

Microsoft Academic Search

We studied foraging habitat use of Wood Storks (Mycteria americana) from three coastal colonies us- ing United States Fish and Wildlife Service National Wetlands Inventory data within a geographic information sys- tem (GIS). Observers followed storks from breeding colonies to foraging sites in a fixed-winged aircraft. The main objectives of the study were to estimate the foraging range of each

Karen F. Gaines; Bryan A. Lawrence Jr; Philip M. Dixon; Michael J. Harris

1998-01-01

484

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...

485

Breeding Better Forages to Help Feed Man and Preserve and Enhance the Environment  

ERIC Educational Resources Information Center

Discusses the importance of forages in agriculture, and expresses the need for the same high level of technology that is used in the production of corn, wheat, and rice to be applied to forage production. Describes promising forage species, breeding objectives, and breeding procedures used in research. (JR)

Burton, Glenn W.

1973-01-01

486

Original article How honey bees forage for pollen at skunk cabbage,  

E-print Network

Original article How honey bees forage for pollen at skunk cabbage, Symplocarpus f Bees forage on a variety of flowers to ob- tain pollen. Little has been written on the foraging pattern they are sometimes unscented. They are protogynous and, in the male phase, produce pollen copiously. Pollen

Paris-Sud XI, Université de

487

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

488

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

489

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

490

Foraging games between gerbils and their predators: temporal dynamics of resource depletion and apprehension in gerbils  

Microsoft Academic Search

Predator-prey interactions constitute a foraging game when prey individuals manage risk from predators and predator individuals manage fear in their prey. As tools for managing risk, clever prey can use time allocation and apprehension (redirecting attention from foraging to predator detection). One such foraging game occurs between gerbils and their predators on the sand dunes of the Negev Desert. Here,

Burt P. Kotler; Joel S. Brown; Sasha R. X. Dall; Shaan Gresser; David Ganey; Amos Bouskila

2002-01-01

491

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...

492

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...

493

Spatial foraging patterns and colony energy status in the African honey bee, Apis mellifera scutellata  

Microsoft Academic Search

The relationship between changes in foraging patterns (inferred from waggle dance activity) and colony energy status (inferred from brood rearing activity, food storage, and colony weight) was examined for the African honey bee during a period of relative resource abundance and resource dearth. When resources were more abundant mean foraging distances (about 400 m) and foraging areas (4–5 km2) were

Stanley S. Schneider; Linda C. McNally

1993-01-01

494

A MACROSCOPIC PROBABILISTIC MODEL OF ADAPTIVE FORAGING IN SWARM ROBOTICS SYSTEMS  

E-print Network

A MACROSCOPIC PROBABILISTIC MODEL OF ADAPTIVE FORAGING IN SWARM ROBOTICS SYSTEMS Wenguo Liu, Alan F In this paper, we have extended a macroscopic probabilistic model of a swarm of homoge- neous foraging robots to a swarm of heterogeneous foraging robots. Each robot is capable of adjusting its searching time threshold

Winfield, Alan FT

495

The influence of social interactions on the foraging path of Bewick's Swans Cygnus columbianus bewickii  

Microsoft Academic Search

The efficiency in which high-density food patches are found is determined by the way foragers move between patches. In this study we explore the effect of social interactions on the foraging path, in particular the distance moved between patches. We studied Bewick¿s Swans Cygnus columbianus bewickii that foraged on belowground tubers of Fennel Pondweed Potamogeton pectinatus. We accurately mapped the

R. H. G. Klaassen; B. A. Nolet; D. Bankert

2006-01-01

496

Original article Protein degradation in the rumen of red clover forage  

E-print Network

Original article Protein degradation in the rumen of red clover forage at various stages of growth (NAN)). The measurements were carried out on 4 sheep fed successively various red clover forages. These forages included the initial growth of fresh red clover (50% bud, first flower, and full flower

Boyer, Edmond

497

PIGEON PEA: A POTENTIAL FORAGE AND GRAIN FOR THE SOUTHERN GREAT PLAINS IN U.S.  

Technology Transfer Automated Retrieval System (TEKTRAN)

A basic goal of livestock grazing programs is to provide high-quality forage year-around to reduce costs of storing and purchasing forage or concentrated feeds. Forage-based livestock production is a significant component of the agricultural economy throughout the Southern Great Plains of the U.S. ...

498

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...

499

Wing wear affects wing use and choice of floral density in foraging bumble bees  

Microsoft Academic Search

Damage to structures that enable mobility can potentially influence foraging behavior. Bumble bees vary in extent of individual wing wear, a trait predicted to affect mechanical performance during foraging. This study asks 1) do bumble bees distribute themselves across different floral densities in accordance with their concurrent wing wear? and 2) does wing use in foraging bumble bees depend on

Danusha J. Foster; Ralph V. Cartar

2011-01-01

500

Selective differences between naive and experienced cattle foraging among eight grasses  

Microsoft Academic Search

Cattle are often required to adapt to new forages when they are moved to new pasture. The objectives of this research were: (1) to determine how rapidly naive cattle express clearly defined preferences when they encounter a new array of forages, and (2) to compare their evolving forage preferences and grazing behavior with those of experienced cattle. Three naive and

David Ganskopp; Ruben Cruz

1999-01-01