Journal articles: 'Prey'

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Tomatsuri, Morihiko, and Koetsu Kon. "Comparison of Three Methods for Determining the Prey Preference of the Muricid SnailReishia clavigera." Journal of Marine Biology 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/484392.

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We propose an appropriate method for investigating the prey preferences of the muricid snailReishia clavigera(Küster, 1860) with limited collection of live prey. We compared 3 methods for examining the prey preference. The first was a predation experiment, conducted with dead prey instead of live prey. The second was a prey choice test using a few preys. In this experiment, both live and dead prey were used. The last method was a stable isotope analysis ofR. clavigeraand its putative prey items. Using live prey, bivalves were the most preferred prey, but goose barnacle was the most preferred prey species in experiments using dead prey. The carbon and nitrogen stable isotope analysis supported the live prey experiment. SinceR. clavigeraprefer preying on live prey but will scavenge or cannibalize when no other food is available in natural habitats, experimental methods using dead prey are not suitable for investigating its prey preferences. Considering the damage to natural habitats, the prey choice test is ecologically benign. Taken together, our findings suggested the prey choice test is the most appropriate method of identifying the prey preferences of muricid snails when large numbers of live preys are difficult to collect.

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SHOLIHAH, TYAN HIDAYATUS. "MODEL MATEMATIKA MANGSA PEMANGSA TIGA SPESIES DENGAN FUNGSI RESPON HOLLING TIPE II DAN HOLLING TIPE IV SERTA PEMANENAN PADA POPULASI MANGSA." MATHunesa: Jurnal Ilmiah Matematika 8, no. 2 (July 11, 2020): 168–73. http://dx.doi.org/10.26740/mathunesa.v8n2.p168-173.

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In this world, living things are interdependent. Every living creature needs another living creature, so there is an interaction between the two. One of interactions that occur in mini style is predator prey interaction. The interaction of prey and predator in the world of ecology is an important and interesting thing to discuss. Therefore many researchers make mathematical models of predator prey to find out the interacions of these prey predators. In this study involved three species, namely two species of prey and one species of predator. Concerning predatory prey behavior with Holling type II, and Holling type IV response functions and harvesting in second prey populations. In this study, the type IV Holling function is used when the predator preys on the first prey, and the type II Holling response function is used when the predator preys on the second prey. This research is a type of quantitative research that examines theories and concepts relating to the problems discussed in this study through various literature sources. This article specifically discusses concerning the construction of predator prey models with Holling type II, and Holling type IV response functions as well as harvesting in the second prey population models obtained from the results of construction in this study are in equation (21).

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Putri, Riris Nur Patria, Windarto Windarto, and Cicik Alfiniyah. "Analisis Kestabilan Model Predator-Prey dengan Adanya Faktor Tempat Persembunyian Menggunakan Fungsi Respon Holling Tipe III." Contemporary Mathematics and Applications (ConMathA) 3, no. 2 (October 13, 2021): 88. http://dx.doi.org/10.20473/conmatha.v3i2.30493.

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Predation is interaction between predator and prey, where predator preys prey. So predators can grow, develop, and reproduce. In order for prey to avoid predators, then prey needs a refuge. In this thesis, a predator-prey model with refuge factor using Holling type III response function which has three populations, i.e. prey population in the refuge, prey population outside the refuge, and predator population. From the model, three equilibrium points were obtained, those are extinction of the three populations which is unstable, while extinction of predator population and coexistence are asymptotic stable under certain conditions. The numerical simulation results show that refuge have an impact the survival of the prey.

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Abdul Manaf, Zati Iwani, and Mohd Hafiz Mohd. "Dynamical System Analysis of the Prey-predator Interactions involving Prey Refuge and Herd Behaviors in Preys." Malaysian Journal of Fundamental and Applied Sciences 18, no. 1 (February 28, 2022): 105–15. http://dx.doi.org/10.11113/mjfas.v18n1.2415.

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By employing a prey refuge mechanism, more preys can be protected from predation. Prey species are also better protected from predation when they congregate in herds. However, what if the prey refuge and herd behavior mechanisms were combined in a system? To investigate this phenomenon, we consider two different prey-predator systems with prey refuge capacity. The first system is a simple prey-predator with prey refuge, whereas the second system considers prey refuge and prey herd behavior mechanisms. Using these models, we explore how different prey refuge strategies affect species interactions in both systems. To accomplish this, we use theoretical techniques (e.g., computing steady states and performing the stability analysis) and numerical bifurcation analysis to demonstrate various dynamical behaviors of these two prey-predator systems. Once prey refuge is treated as a bifurcation parameter, we observe the occurrence of supercritical Hopf and transcritical bifurcations in both systems. Furthermore, we explore the dynamic effects of prey refuge and predator handling time on species population interactions: our findings reveal that using both prey refuge and herd behavior as escape strategies; it is possible to dilute the predation pressure and ensure species biodiversity.

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Zhang, Hui, Zhihui Ma, Gongnan Xie, and Lukun Jia. "Effects of Behavioral Tactics of Predators on Dynamics of a Predator-Prey System." Advances in Mathematical Physics 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/375236.

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A predator-prey model incorporating individual behavior is presented, where the predator-prey interaction is described by a classical Lotka-Volterra model with self-limiting prey; predators can use the behavioral tactics of rock-paper-scissors to dispute a prey when they meet. The predator behavioral change is described by replicator equations, a game dynamic model at the fast time scale, whereas predator-prey interactions are assumed acting at a relatively slow time scale. Aggregation approach is applied to combine the two time scales into a single one. The analytical results show that predators have an equal probability to adopt three strategies at the stable state of the predator-prey interaction system. The diversification tactics taking by predator population benefits the survival of the predator population itself, more importantly, it also maintains the stability of the predator-prey system. Explicitly, immediate contest behavior of predators can promote density of the predator population and keep the preys at a lower density. However, a large cost of fighting will cause not only the density of predators to be lower but also preys to be higher, which may even lead to extinction of the predator populations.

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Borme, Diego, Sara Legovini, Alessandra de Olazabal, and Valentina Tirelli. "Diet of Adult Sardine Sardina pilchardus in the Gulf of Trieste, Northern Adriatic Sea." Journal of Marine Science and Engineering 10, no. 8 (July 25, 2022): 1012. http://dx.doi.org/10.3390/jmse10081012.

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Food availability is thought to exert a bottom-up control on the population dynamics of small pelagic fish; therefore, studies on trophic ecology are essential to improve their management. Sardina pilchardus is one of the most important commercial species in the Adriatic Sea, yet there is little information on its diet in this area. Adult sardines were caught in the Gulf of Trieste (northern Adriatic) from spring 2006 to winter 2007. Experimental catches conducted over 24-h cycles in May, June and July showed that the sardines foraged mainly in the late afternoon. A total of 96 adult sardines were analysed: the number of prey varied from a minimum of 305 to a maximum of 3318 prey/stomach, with an overall mean of 1259 ± 884 prey/stomach. Prey items were identified to the lowest possible taxonomical level, counted and measured at the stereo-microscope. Overall, sardines fed on a wide range of planktonic organisms (87 prey items from 17 μm to 18.4 mm were identified), with copepods being the most abundant prey (56%) and phytoplankton never exceeding 10% of the prey. Copepods of the Clauso-Paracalanidae group and of the genus Oncaea were by far the most important prey. The carbon content of prey items was indirectly estimated from prey dry mass or body volume. Almost all carbon uptake relied on a few groups of zooplankton. Ivlev’s selectivity index showed that sardines positively selected small preys (small copepods < 1 mm size), but also larger preys (such as teleost eggs, decapod larvae and chaetognaths), confirming their adaptive feeding capacity.

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Tilahun, Surafel Luleseged, and Hong Choon Ong. "Prey-Predator Algorithm: A New Metaheuristic Algorithm for Optimization Problems." International Journal of Information Technology & Decision Making 14, no. 06 (November 2015): 1331–52. http://dx.doi.org/10.1142/s021962201450031x.

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Nature-inspired optimization algorithms have become useful in solving difficult optimization problems in different disciplines. Since the introduction of evolutionary algorithms several studies have been conducted on the development of metaheuristic optimization algorithms. Most of these algorithms are inspired by biological phenomenon. In this paper, we introduce a new algorithm inspired by prey-predator interaction of animals. In the algorithm randomly generated solutions are assigned as a predator and preys depending on their performance on the objective function. Their performance can be expressed numerically and is called the survival value. A prey will run towards the pack of preys with better surviving values and away from the predator. The predator chases the prey with the smallest survival value. However, the best prey or the prey with the best survival value performs a local search. Hence the best prey focuses fully on exploitation while the other solution members focus on the exploration of the solution space. The algorithm is tested on selected well-known test problems and a comparison is also done between our algorithm, genetic algorithm and particle swarm optimization. From the simulation result, it is shown that on the selected test problems prey-predator algorithm performs better in achieving the optimal value.

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E. Alhejaze, Zeinb. "ANALYSIS OF A PREY – PREDATOR MODEL WITH GENERAL INCIDENCE." EPH - International Journal of Applied Science 1, no. 1 (March 27, 2015): 17–19. http://dx.doi.org/10.53555/eijas.v1i2.146.

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In this paper we have analyzed prey-predator systems where the prey population is divided into two groups, infected. Also we have considered the effect of intraspecific competition between infected preys as well as on predator where the species observed in nature species does not exist alone. In this paper we discuss different systems of prey – predator model of the general 2dimensional with general incidence H(S, I). Also, study discuss different systems of a prey – predator model with general incidence H(S,I). The aim of this paper is to study the dynamical behavior of a prey – predator model by different techniques with generalized incidence term.

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Stephano, Mussa Amos, and Il Hyo Jung. "Effects of Refuge Prey on Stability of the Prey-Predator Model Subject to Immigrants: A Mathematical Modelling Approach." Tanzania Journal of Science 47, no. 4 (October 28, 2021): 1376–91. http://dx.doi.org/10.4314/tjs.v47i4.4.

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Prey-predator system is enormously complex and nonlinear interaction between species. Such complexity regularly requires development of new approaches which involves more factors in analysis of its population dynamics. In this paper, we formulate a modified Lotka-Volterra model that incorporates factors such as refuge prey and immigrants. We investigate the effects of refuge prey and immigrants by varying the refuge factor, with and without immigrants. The results show that with Holling’s type I functional response, the proposed model is asymptotically convergent when a refuge prey factor is introduced. Moreover, with Holling’s type II functional response, the proposed mathematical model is unstable and does not converge. However, with Holling’s type III functional response in a system, the proposed mathematical model is asymptotically stable. These results point out the following remarks: The effects of refuge prey on stability of the dynamical system vary depending on the type of functional response, and when the predator population increases, the likelihood of prey extinction declines when the proportion of preys in refuge population increases. Hence, the factor of refuge prey is crucial for controlling the population of the predator and obtaining balances between prey and predator in the ecosystem. Keywords: Refuge prey, stability, prey-predator, immigrants, Mathematical modelling

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Orgad, Zvi. "Prey of Pray: Allegorizing the Liturgical Practice." Arts 9, no. 1 (December 30, 2019): 3. http://dx.doi.org/10.3390/arts9010003.

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Numerous images embedded in the painted decorations in early modern Central and Eastern European synagogues conveyed allegorical messages to the congregation. The symbolism was derived from biblical verses, stories, legends, and prayers, and sometimes different allegories were combined to develop coherent stories. In the present case study, which concerns a bird, seemingly a nocturnal raptor, depicted on the ceiling of the Unterlimpurg Synagogue, I explore the symbolism of this image in the contexts of liturgy, eschatology, and folklore. I undertake a comparative analysis of paintings in medieval and early modern illuminated manuscripts—both Christian and Jewish—and in synagogues in both Eastern and Central Europe. I argue that in some Hebrew illuminated manuscripts and synagogue paintings, nocturnal birds of prey may have been positive representations of the Jewish people, rather than simply a response to their negative image in Christian literature and art, but also a symbol of redemption. In the Unterlimpurg Synagogue, the night bird of prey, combined with other symbolic elements, represented a complex allegoric picture of redemption, possibly implying the image of King David and the kabbalistic nighttime prayer Tikkun Ḥaẓot. This case study demonstrates the way in which early modern synagogue painters created allegoric paintings that captured contemporary religious and mystical ideas and liturgical developments.

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Zhang, Jingyuan, and Yan Yang. "Three-Prey One-Predator Continuous Time Nonlinear System Model." Complexity 2020 (October 10, 2020): 1–11. http://dx.doi.org/10.1155/2020/8869989.

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In this paper, we propose a new multiple-prey one-predator continuous time nonlinear system model, in which the number of teams of preys is equal to 3; namely, a continuous time three-prey one-predator model is put forward and studied. The fourth-order differential equation is established, in which the prey teams help each other. The equilibrium points and stability are analyzed. When not considering preys help each other, we study the global stability and persistence of the model without help terms. The simulation results of system solutions with help terms corresponding to locally asymptotically stable equilibrium points and without help terms corresponding to globally asymptotically stable equilibrium points are given.

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Sabagh, Leandro Talione, Ana Maria Paulino Telles Carvalho-e-Silva, and Carlos Frederico Duarte Rocha. "Diet of the toad Rhinella icterica (Anura: Bufonidae) from Atlantic Forest Highlands of southeastern Brazil." Biota Neotropica 12, no. 4 (December 2012): 258–62. http://dx.doi.org/10.1590/s1676-06032012000400027.

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In this study, we present some information of the regarding throphic niche from the anuran toad Rhinella icterica living in high altitudes above 2000 m a.s.l. from a habitat of the Atlantic Forest Biome - the Altitude Fields in the Itatiaia National Park. We found 150 prey items in toad stomachs, belonging to five prey types, as well as skin remains and some remains of plant material. The index of relative importance indicated that most important prey types were beetles and ants, these last composing 70% of the diet numerically and the trophic niche breadth (B) was 1.81. The relatively low diversity of prey types we recorded in the diet of R. icterica of Itatiaia and numerically dominated by ants suggests some preference for this item. We do not found significant relationship between the toad measurements with the preys' measurements. We concluded that R. icterica toads at the highlands of Itatiaia feeds on arthropods, mainly ants and coleopterans and that the high consumption of preys with relatively small and similar size as ants in the diet prevents an expected relationship among frog body or mouth size and prey volume and size.

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Sih, Andrew, and David E. Wooster. "Prey Behavior, Prey Dispersal, and Predator Impacts on Stream Prey." Ecology 75, no. 5 (July 1994): 1199–207. http://dx.doi.org/10.2307/1937446.

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Fitzmaurice, Dylan, Puja Saha, Megan E. Nunez, Eileen M. Spain, Catherine M. Volle, and Megan A. Ferguson. "Adhesion Forces in Bacterial Predator-Prey and Prey-Prey Systems." Biophysical Journal 116, no. 3 (February 2019): 431a. http://dx.doi.org/10.1016/j.bpj.2018.11.2317.

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Johansson, Frank. "Increased prey vulnerability as a result of prey-prey interactions." Hydrobiologia 308, no. 2 (July 1995): 131–37. http://dx.doi.org/10.1007/bf00007398.

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Jackson, Robert R., Daiqin Li, Jeremy R. W. Woon, Rosli Hashim, and Fiona R. Cross. "Intricate predatory decisions by a mosquito-specialist spider from Malaysia." Royal Society Open Science 1, no. 2 (October 2014): 140131. http://dx.doi.org/10.1098/rsos.140131.

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Paracyrba wanlessi is a southeast Asian jumping spider (Salticidae) that lives in the hollow internodes of fallen bamboo and preys on the larvae, pupae and adults of mosquitoes. In contrast to Evarcha culicivora , an East African salticid that is also known for actively targeting mosquitoes as preferred prey, there was no evidence of P . wanlessi choosing mosquitoes on the basis of species, sex or diet. However, our findings show that P . wanlessi chooses mosquitoes significantly more often than a variety of other prey types, regardless of whether the prey are in or away from water, and regardless of whether the mosquitoes are adults or juveniles. Moreover, a preference for mosquito larvae, pupae and adults is expressed regardless of whether test spiders are maintained on a diet of terrestrial or aquatic prey and regardless of whether the diet includes or excludes mosquitoes. Congruence of an environmental factor (in water versus away from water) with prey type (aquatic versus terrestrial mosquitoes) appeared to be important and yet, even when the prey were in the incongruent environment, P . wanlessi continued to choose mosquitoes more often than other prey.

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Aljahdaly, Noufe H., and Manar A. Alqudah. "Analytical Solutions of a Modified Predator-Prey Model through a New Ecological Interaction." Computational and Mathematical Methods in Medicine 2019 (October 16, 2019): 1–7. http://dx.doi.org/10.1155/2019/4849393.

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The predator-prey model is a common tool that researchers develop continuously to predict the dynamics of the animal population within a certain phenomenon. Due to the sexual interaction of the predator in the mating period, the males and females feed together on one or more preys. This scenario describes the ecological interaction between two predators and one prey. In this study, the nonlinear diffusive predator-prey model is presented where this type of interaction is accounted for. The influence of this interaction on the population of predators and preys is predicted through analytical solutions of the dynamical system. The solutions are obtained by using two reliable and simple methods and are presented in terms of hyperbolic functions. In addition, the biological relevance of the solutions is discussed.

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Nielsen, M.-C., M. M. Davidson, and R. C. Butler. "Predation rate of Thrips tabaci larvae by Neoseiulus cucumeris is influenced by prey density and presence of a host plant." New Zealand Plant Protection 67 (January 8, 2014): 197–203. http://dx.doi.org/10.30843/nzpp.2014.67.5732.

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Prey consumption rate by natural enemies may be affected by the preys host plant and prey density The predation rate of the mite Neoseiulus cucumeris at different densities of firstinstar Thrips tabaci larvae in the presence (onion) or absence (green plastic) of a host was measured In the first experiment using a disc bioassay N cucumeris exhibited a typeII densitydependent functional response to prey on both disc types Prey consumption was reduced on onion relative to plastic A second experiment using onion bulbs and green plastic bulbs indicated a decrease in the consumption rate on plastic bulbs compared with plastic discs The survival or recapture of N cucumeris on onion bulbs was less than 7 and no prey consumption data were obtained The results indicate that onion as a host plant has a negative effect on consumption of T tabaci by N cucumeris and on survival of the predator mite

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Varga, Doc. "Prey." After Dinner Conversation 2, no. 5 (2021): 5–44. http://dx.doi.org/10.5840/adc20212541.

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When is suicide acceptable? Are their acceptable and unacceptable reasons for suicide? In this work of philosophical short story fiction, Jared has decided to enter a government program that, after 15 hours of counseling, will allow him to legally take his own life. Doctor Ansley is the top government therapist with 199 “saves” for the year. After several sessions it becomes clear that Jared has serious conviction about dying, but he also has a secret reason for his choice. Only after Doctor Ansley tricks him by giving him a fake test does he divulge his true reason for wanting to die. Jared believes the earth is feeding off of humans and has instilled, through chemical responses, our desire to stay alive so we will continue feeding it. In short, all humans are the earth’s food source and, only by becoming unattached from being alive, can we break the cycle. Jared completes the required sessions and dies. And Doctor Ansley now has questions as well.

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MacCarthy, Catherine Phil. "Prey." College English 61, no. 4 (March 1999): 474. http://dx.doi.org/10.2307/378926.

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Goodwin, June. "Prey." Women's Review of Books 8, no. 2 (November 1990): 24. http://dx.doi.org/10.2307/4020874.

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Wrigley, Robert. "Prey." Manoa 32, no. 1 (2020): 141. http://dx.doi.org/10.1353/man.2020.0036.

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Stein, Gary. "Prey." JAMA 304, no. 2 (July 14, 2010): 133. http://dx.doi.org/10.1001/jama.2010.652.

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Keshari, Nishi, and R. S. Kanwar. "The Predation Behaviour of Fictor composticola on Parasitic Nematodes of Button Mushroom, Agaricus bisporus." International Journal of Bio-resource and Stress Management 12, no. 6 (December 31, 2021): 751–58. http://dx.doi.org/10.23910/1.2021.2430.

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In this study, the predation behaviour of male and female predatory nematode, Fictor composticola, was studied on five prey nematode species, Aphelenchus avenae, Aphelenchoides swarupi, Ditylenchus myceliophagus, Bursilla sp. and Panagrolaimus sp., found in the white button mushroom compost. The period of the study is of six months. The data recorded on number of encounters, part of the body of prey attacked, stage of the prey attacked, duration of feeding etc. The strike rate and prey susceptibility were calculated. The average number of encounters on all the five preys done by female F. composticola was 3.0 and that of the male was 6.0. Male F. composticola had more number of encounters on the prey nematode species than the females. Both the sexes preferred juvenile stages over adults as prey. The most attacked part by both females and males predator, was the posterior part of the prey body. In 80% of cases, female predators fed on the first encountered prey while males attacked the first encountered prey in 30% of cases only. The strike rate of female F. composticola was more (78.6%) than the male (48.2%). Mycophagous nematodes were more susceptible to predator’s attack than the microbivorous nematodes. The strike rate of the predator on different prey nematode species was found more on mycophagous nematodes than on microbivorous nematodes and minimum on Panagrolaimus sp. The average feeding duration of female F. composticola was 8 min and 31 sec and in the case of males it was 4 min and 11 sec.

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Villares Junior, GA, and R. Goitein. "Variations of Salminus hilarii diet (Ostariophysi, Characidae): seasonal and ontogenetic effects." Brazilian Journal of Biology 75, no. 3 (September 25, 2015): 574–80. http://dx.doi.org/10.1590/1519-6984.17213.

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AbstractThis study described the variations seasonal and ontogenetic of Salminus hilarii diet. Samples were collected in the Sorocaba River, São Paulo, Brazil, one of the few rivers where individuals of the species still occur in a higher frequency. The preys consumed were analyzed by Importance Alimentary Index (AIi). To determine similarities between year seasons, the AIi data were analyzed by the Morisita-Horn index and reduced in cluster analysis, along with a statistical comparison made by one-way ANOSIM test (5%). The feeding activity was analyzed according to the stomach repletion index and compared among the year seasons using non parametric variance analysis Kruskal-Wallis test (5%). Comparison of prey consumed between immature and adult individuals was made by Spearman correlation (5%). A Pearson correlation (5%) was applied between the standard length of the fish and prey consumed, as well as between the mouth and prey heights. The analyzes of stomach contents showed that the diet of this species was exclusively piscivorous, with significant difference of prey consumption during the period, the same happening among adult and immature individuals. It was observed that these fishes use to swallow their prey whole and that significant correlations between size of predator and prey size can be observed. There is also correlation between the mouth height and the maximum prey depth. Salminus hilarii feeds on the available prey, and the species food composition and feeding activity depends on prey`s abundance, their size and morphology, as do the water temperatures.

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Catarino, Michel F., and Jansen Zuanon. "Feeding ecology of the leaf fish Monocirrhus polyacanthus (Perciformes: Polycentridae) in a terra firme stream in the Brazilian Amazon." Neotropical Ichthyology 8, no. 1 (March 2010): 183–86. http://dx.doi.org/10.1590/s1679-62252010000100022.

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Monocirrhus polyacanthus (Polycentridae) is a remarkable leaf-mimicking fish that inhabits streams, lake and river margins along the Amazon basin. Despite its obvious predatory habits and being frequently present in the international aquarium trade, little is known about its diet under natural conditions. We examined 35 specimens of leaf fish (28.5-82.0 mm SL), of which 19 had food the stomach. Thirty-three preys were found in the stomach contents, 19 of which were measured (2.0-33.0 mm total length). Up to five preys were found in the stomach contents of a single leaf fish specimen. The diet of the leaf fish was constituted by fish (63.15% FO, n = 12) and invertebrates (36.3% FO, n = 4); fish and invertebrate preys occurred together in three stomachs (15.8% FO). Of the 33 prey found in the stomachs, 21 were fish and 12 invertebrates. Among the consumed prey fishes, Characiformes and Perciformes represented 76.1% and 14.2% respectively. Characidae was the most commonly recorded prey family, followed by Lebiasinidae. Invertebrates were represented by shrimps (Decapoda) and insects (Coleoptera, Hymenoptera, Ephemeroptera and Odonata). There was a positive relation between the size of the leaf fish specimens and of its consumed preys. The combination of leaf fish's visually effective body camouflage and the reduced activity of the characids at crepuscular hours probably allow the capture of such fast moving preys. The coiled position of the fishes found in the stomach of M. polyacanthus possibly allowed the accommodation of more than one prey simultaneously, which seems to be important for predators that consume proportionally large preys that are captured only occasionally.

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Sih, Andrew. "Prey refuges and predator-prey stability." Theoretical Population Biology 31, no. 1 (February 1987): 1–12. http://dx.doi.org/10.1016/0040-5809(87)90019-0.

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Yakubu, Abdul-Aziz. "Prey dominance in discrete predator-prey systems with a prey refuge." Mathematical Biosciences 144, no. 2 (September 1997): 155–78. http://dx.doi.org/10.1016/s0025-5564(97)00026-6.

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Journal, Baghdad Science. "Response of green lacewing Chrysoperla carnea (Stephens) to various densities of Ephestia cautella (walk)eggs." Baghdad Science Journal 11, no. 3 (September 7, 2014): 1094–99. http://dx.doi.org/10.21123/bsj.11.3.1094-1099.

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Results of exposure larvae of the most important predator in the integrated pest management , the green lacewings, Chrysoperla carnea (Stephens) to various densities of fig moth Ephestia cautella eggs showed increasing in the number of consumed prey at decreasing rate of increasing prey density where curve slope consumption decreased gradually until leveling off. These specifications concurred with type II functional response that predators appear towards varied densities of its preys ,that was confirm by logistic regression between the proportion of prey eaten in relation to prey offered . Third larval instars of the predator showed attack rate (a) of 4.85. This was greater than the second larval instar (3.58). Handling time (Th) per prey decreased as the predator aged , it was 0.0046 day for the second larval instar and 0.0041 day for the third larval instars. The greatest theoretical maximum number of moth eggs to be consumed was 244 eggs/day for the third larval instar followed by second larval instars as 217 eggs/day, respectively.

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Wang, Yuangan. "Stability Analysis of Predator-Prey System with Fuzzy Impulsive Control." Journal of Applied Mathematics 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/715497.

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Having attracted much attention in the past few years, predator-prey system provides a good mathematical model to present the correlation between predators and preys. This paper focuses on the robust stability of Lotka-Volterra predator-prey system with the fuzzy impulsive control model, and Takagi-Sugeno (T-S) fuzzy impulsive control model as well. Via the T-S model and the Lyapunov method, the controlling conditions of the asymptotical stability and exponential stability are established. Furthermore, the numerical simulation for the Lotka-Volterra predator-prey system with impulsive effects verifies the effectiveness of the proposed methods.

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Marchessaux, Guillaume, Bruno Belloni, Justine Gadreaud, and Delphine Thibault. "Predation assessment of the invasive ctenophore Mnemiopsis leidyi in a French Mediterranean lagoon." Journal of Plankton Research 43, no. 2 (February 4, 2021): 161–79. http://dx.doi.org/10.1093/plankt/fbab002.

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Abstract Since 2000, the invasive ctenophore Mnemiopsis leidyi has been recorded in Mediterranean brackish lagoons. Quantitative data on its feeding behavior (i.e. potential ecological impact) in these particular environments are non-existent. In this study, we describe in situ predation dynamics of M. leidyi in the Berre Lagoon (south-eastern France) over a 22-month survey. Ctenophores were fixed in a solution of formalin in brackish water, allowing the study of the prey items in the gastric cavities at different time scales. The number of prey items ingested is influenced by the ctenophore biovolume, from 8 (0.5 mL) to 1 207 prey ind−1 (35 mL), and by temperature of 3.4°C (2 ± 2 prey ind−1) to 23.2°C (517 ± 295 prey ind−1). Gut evacuation time is strongly related to temperature and ranged from 80 (25°C) to 160 min (9°C). Mnemiopsis leidyi diet changed seasonally following in situ concentrations of prey. The less mobile preys such as mollusks and barnacles were the most impacted. The ctenophore predation pressure on the zooplankton assemblage could lead at time to a release of grazing pressure on phytoplankton and favor the eutrophication of the lagoon.

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Whitford, Malachi D., Grace A. Freymiller, Timothy E. Higham, and Rulon W. Clark. "Shaking things up: the unique feeding behaviour of western banded geckos when consuming scorpions." Biological Journal of the Linnean Society 135, no. 3 (January 5, 2022): 533–40. http://dx.doi.org/10.1093/biolinnean/blab167.

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Abstract Predators that feed on dangerous prey species must evolve mechanisms to reduce the likelihood of injury or death during a predation attempt. Scorpions are prime examples of dangerous prey items for insectivores, because they can inflict a venomous and potentially fatal sting when attacked. Despite this risk, the western banded gecko (Coleonyx variegatus), a generalist insectivore, occasionally preys on dune scorpions (Smeringurus mesaensis). We use high-speed videography to examine the modulation of prey capture biomechanics in relationship to prey type. The capture of undefended evasive (cricket) and non-evasive (worms) prey follows previous studies of lizard attack kinematics. However, we have discovered a unique shake-feeding behaviour used by western banded geckos when feeding on scorpions, whereby the gecko bites the scorpion, then performs very rapid side-to-side shaking with its head and body. Given the speed and violence of shake-feeding, we suggest that geckos shake the scorpion to cause mass trauma and subsequent immobility or, potentially, to break the stinger and render the scorpion harmless. This behaviour might be widespread among geckos that feed on these dangerous prey species.

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Pizzatto, Lígia, Otavio Marques, and Kátia Facure. "Food habits of Brazilian boid snakes: overview and new data, with special reference to Corallus hortulanus." Amphibia-Reptilia 30, no. 4 (2009): 533–44. http://dx.doi.org/10.1163/156853809789647121.

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AbstractThis study examines the diet of eight boid snakes: Boa c. constrictor, Boa c. amarali, Corallus caninus, C. hortulanus, Epicrates cenchria, E. crassus, E. assisi and Eunectes murinus mainly by analyzing the gut contents of preserved museum specimens, and includes a literature review to present an overview of the diet of Brazilian boids. Mammals constitute the primary prey consumed by the majority of the species. Birds are also frequently consumed by C. hortulanus and Boa contrictor, and are the most important prey for B. c. amarali. Ectotherms (mostly lizards) were only consumed by immature snakes. Such prey is rarely consumed by B. c. amarali and not recorded for Epicrates and Eunectes species in our dissections. C. caninus is likely a mammal specialist and Epicrates prey on birds more opportunistically. The niche overlap index varied from 0.27-0.52 for species occurring in the same bioma and geographic range but it is possible this overlap is lower as most sympatric species explore different macrohabitat. C. hortulanus exhibited a significant relationship between prey size and predator head size; this relationship did not differ among mature and immature snakes. In comparison to immature individuals heavier adult snakes fed on heavier prey items however, the ratio between prey/predator mass decreased with increase in predator mass (or size). Most boids exploit diurnal and nocturnal preys, probably using both sit-and-wait and active tactics. They feed on the ground but boas and C. hortulanus and possibly E. cenchria also exploit arboreal prey.

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Guo, Xiaoxia, and Zhiming Guo. "A Markov-switching predator–prey model with Allee effect for preys." International Journal of Biomathematics 13, no. 03 (March 25, 2020): 2050018. http://dx.doi.org/10.1142/s1793524520500187.

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This paper concerns with a Markov-switching predator–prey model with Allee effect for preys. The conditions under which extinction of predator and prey populations occur have been established. Sufficient conditions are also given for persistence and global attractivity in mean. In addition, stability in the distribution of the system under consideration is derived under some assumptions. Finally, numerical simulations are carried out to illustrate theoretical results.

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Harland, Duane P., and Robert R. Jackson. "Influence of cues from the anterior medial eyes of virtual prey onPortia fimbriata, an araneophagic jumping spider." Journal of Experimental Biology 205, no. 13 (July 1, 2002): 1861–68. http://dx.doi.org/10.1242/jeb.205.13.1861.

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SUMMARYPortia fimbriata from Queensland, Australia, is a jumping spider(Salticidae) that preys on other spiders, including other salticids. Cryptic stalking (palps retracted, walking very slowly and freezing when faced) is a prey-specific tactic deployed exclusively against salticid prey. Using vision alone, P. fimbriata discriminates salticid from non-salticid prey, with the prey salticid's large anterior median (AM) eyes providing critical cues. Here,using computer-rendered virtual three-dimensional lures, we clarify experimentally some of the specific optical cues from AM eyes that influence the behaviour of P. fimbriata. Control lures were based on Jacksonoides queenslandicus, the salticid upon which P. fimbriata most commonly preys in nature. Experimental lures were modified to isolate specific combinations of AM eye features. For presentation to P. fimbriata, lures were projected on a small screen positioned in front of a web-covered platform. Each individual P. fimbriata was tested once with a control lure and once with a lure on which some AM eye feature had been altered. P. fimbriata was affected by the presence-versus-absence of AM eyes, by the size and shape of these eyes and by AM eye position. Horizontal position on the face of a single AM eye had no discernible influence on whether P. fimbriata initiated cryptic stalking, but reduced how often P. fimbriata froze when faced by the prey. The implications of the findings are discussed in relation to perceptual processes underlying the predatory strategy of P. fimbriata.

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Saha, Sangeeta, Alakes Maiti, and G. P. Samanta. "A Michaelis–Menten Predator–Prey Model with Strong Allee Effect and Disease in Prey Incorporating Prey Refuge." International Journal of Bifurcation and Chaos 28, no. 06 (June 15, 2018): 1850073. http://dx.doi.org/10.1142/s0218127418500736.

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Here, we have proposed a predator–prey model with Michaelis–Menten functional response and divided the prey population in two subpopulations: susceptible and infected prey. Refuge has been incorporated in infected preys, i.e. not the whole but only a fraction of the infected is available to the predator for consumption. Moreover, multiplicative Allee effect has been introduced only in susceptible population to make our model more realistic to environment. Boundedness and positivity have been checked to ensure that the eco-epidemiological model is well-behaved. Stability has been analyzed for all the equilibrium points. Routh–Hurwitz criterion provides the conditions for local stability while on the other hand, Bendixson–Dulac theorem and Lyapunov LaSalle theorem guarantee the global stability of the equilibrium points. Also, the analytical results have been verified numerically by using MATLAB. We have obtained the conditions for the existence of limit cycle in the system through Hopf Bifurcation theorem making the refuge parameter as the bifurcating parameter. In addition, the existence of transcritical bifurcations and saddle-node bifurcation have also been observed by making different parameters as bifurcating parameters around the critical points.

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Houston, A. I. "Prey size of single-prey loaders as an indicator of prey abundance." Ecology Letters 3, no. 1 (January 2000): 5–6. http://dx.doi.org/10.1046/j.1461-0248.2000.00110.x.

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SINGH, TEEKAM, and SANDIP BANERJEE. "SPATIAL ASPECT OF HUNTING COOPERATION IN PREDATORS WITH HOLLING TYPE II FUNCTIONAL RESPONSE." Journal of Biological Systems 26, no. 04 (December 2018): 511–31. http://dx.doi.org/10.1142/s0218339018500237.

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In this paper, we have investigated a spatial predator–prey model with hunting cooperation in predators. Using linear stability analysis, we obtain the condition for diffusive instability and identify the corresponding domain in the space of controlling parameters. Using extensive numerical simulations, we obtain complex patterns, namely, spotted pattern, stripe pattern and mixed pattern in the Turing domain, by varying the hunting cooperation parameter in predators and carrying capacity of preys. The results focus on the effect of hunting cooperation in pattern dynamics of a diffusive predator–prey model and help us in better understanding of the dynamics of the predator–prey interaction in real environments.

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Varga, Krisztián, and Attila Kiss. "Cooperation and sharing of caught prey in competitive continuous coevolution using the predator-prey domain." Computer Science and Information Systems, no. 00 (2021): 22. http://dx.doi.org/10.2298/csis201122022v.

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Competition is one of the main driving factors of evolution and can be observed in nature as well as in simulations. Competition can occur between predators and preys causing an arms race, but it can also happen between individuals of the same species. Our simulation uses the predator-prey domain (with carnivores, herbivores and plants,) and continuous (not generation based) neuro-evolution to create a complex environment where both forms of competition arise. The characteristics of the simulation make it hard for a predator to catch prey alone, this creates a dependence on cooperation. The predators can share the caught prey with nearby members, in order to help them work together. We explore how sharing affects the cooperation of the hunters, and compare the effectiveness of one and two predator populations.

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Alivizatos, Haralambos, and Nikolaos Kassinis. "Diet of the Red-footed Falcon (Falco vespertinus) in Cyprus during autumn migration." Ornis Hungarica 29, no. 1 (June 1, 2021): 120–25. http://dx.doi.org/10.2478/orhu-2021-0009.

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Abstract The diet of the Red-footed Falcon (Falco vespertinus) was studied at Akrotiri Peninsula, Cyprus, in October 2008, during the autumn migration. Based on 180 pellets collected that represented 3,066 prey items, the diet consisted exclusively of invertebrates, nearly all preys were insects. Winged ants (Hymenoptera, Formicidae) formed 94% of the diet by number of specimens and 76% of biomass. Beetles (Coleoptera), mainly Carabidae and Scarabaeidae, made up 5% of the prey numbers but 22.5% of biomass. The other preys were made up by small numbers of earwigs (Dermaptera), true bugs (Hemiptera) and snails (Gastropoda).

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Geipel, Inga, Kirsten Jung, and Elisabeth K. V. Kalko. "Perception of silent and motionless prey on vegetation by echolocation in the gleaning bat Micronycteris microtis." Proceedings of the Royal Society B: Biological Sciences 280, no. 1754 (March 7, 2013): 20122830. http://dx.doi.org/10.1098/rspb.2012.2830.

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Gleaning insectivorous bats that forage by using echolocation within dense forest vegetation face the sensorial challenge of acoustic masking effects. Active perception of silent and motionless prey in acoustically cluttered environments by echolocation alone has thus been regarded impossible. The gleaning insectivorous bat Micronycteris microtis however, forages in dense understory vegetation and preys on insects, including dragonflies, which rest silent and motionless on vegetation. From behavioural experiments, we show that M. microtis uses echolocation as the sole sensorial modality for successful prey perception within a complex acoustic environment. All individuals performed a stereotypical three-dimensional hovering flight in front of prey items, while continuously emitting short, multi-harmonic, broadband echolocation calls. We observed a high precision in target localization which suggests that M. microtis perceives a detailed acoustic image of the prey based on shape, surface structure and material. Our experiments provide, to our knowledge, the first evidence that a gleaning bat uses echolocation alone for successful detection, classification and precise localization of silent and motionless prey in acoustic clutter. Overall, we conclude that the three-dimensional hovering flight of M. microtis in combination with a frequent emission of short, high-frequency echolocation calls is the key for active prey perception in acoustically highly cluttered environments.

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Jones, Katherine A., Andrew L. Jackson, and Graeme D. Ruxton. "Prey jitters; protean behaviour in grouped prey." Behavioral Ecology 22, no. 4 (2011): 831–36. http://dx.doi.org/10.1093/beheco/arr062.

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Hethcote, Herbert W., Wendi Wang, Litao Han, and Zhien Ma. "A predator–prey model with infected prey." Theoretical Population Biology 66, no. 3 (November 2004): 259–68. http://dx.doi.org/10.1016/j.tpb.2004.06.010.

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Siemers, Björn M., and René Güttinger. "Prey conspicuousness can explain apparent prey selectivity." Current Biology 16, no. 5 (March 2006): R157—R159. http://dx.doi.org/10.1016/j.cub.2006.02.056.

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Wuhaib, S. A., and N. F. Abd. "CONTROL OF PREY DISEASE IN STAGE STRUCTURE MODEL." Tikrit Journal of Pure Science 25, no. 2 (March 17, 2020): 129. http://dx.doi.org/10.25130/j.v25i2.968.

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In this paper, a mathematical model consisting of the prey-predator model, prey is at risk of disease then become as susceptible and infected, while predator with different stage structure: immature and mature predator, the infected prey is at risk recover and harvest. The function of disease is proportionality function. At the beginning, the reasons of studying stage structure and the dynamic of nontrivial subsystems that may be lead to coexistence of these types of spices explain and by using Maple software, Jacobean matrix, Routh-Hurwitz criterion, Bendixson-Dulac criterion and Lyapunov function to prove the existence, periodic solution, local and global stability. We concluded that the survival for two preys are possible through the non-periodic solution due to the Bendixson-Dulac criterion, also the immature predator neither attack preys nor yield offspring's and die when the mature predator extinction, the global stability conditions for the original system be stretch of global stability conditions for subsystems. Finally, Mathematica software employs to describe some results in numerical simulation http://dx.doi.org/10.25130/tjps.25.2020.040

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Harland, D. P., and R. R. Jackson. "Cues by which Portia fimbriata, an araneophagic jumping spider, distinguishes jumping-spider prey from other prey." Journal of Experimental Biology 203, no. 22 (November 15, 2000): 3485–94. http://dx.doi.org/10.1242/jeb.203.22.3485.

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Portia fimbriata from Queensland, Australia, is an araneophagic jumping spider (Salticidae) that includes in its predatory strategy a tactic (cryptic stalking) enabling it to prey effectively on a wide range of salticids from other genera. Optical cues used by P. fimbriata to identify the salticid species on which it most commonly preys, Jacksonoides queenslandicus, were investigated experimentally in the laboratory using odorless lures made from dead prey on which various combinations of features were altered. P. fimbriata adopted cryptic stalking only against intact salticid lures and modified lures on which the large anterior-median eyes were visible. Ordinary stalking was usually adopted when the lure did not have the anterior-median eyes visible. There was no evidence that cues from the legs of prey salticids influence the choice of stalking style of P. fimbriata, but cues from the legs do appear to influence strongly whether a prey is stalked at all. Cues from the cephalothorax and abdomen also influenced the stalking tendency, but to a lesser degree than cues from the legs. An algorithm to describe the perceptual processes of P. fimbriata when visually discriminating between salticid and non-salticid prey is discussed.

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Garrone-Neto, Domingos, and Ivan Sazima. "Stirring, charging, and picking: hunting tactics of potamotrygonid rays in the upper Paraná River." Neotropical Ichthyology 7, no. 1 (March 2009): 113–16. http://dx.doi.org/10.1590/s1679-62252009000100015.

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Hunting tactics of potamotrygonid freshwater rays remain unreported under natural conditions. Three main foraging tactics of Potamotrygon falkneri and P. motoro are described here based on underwater observations in the upper Paraná River. Both species displayed similar behaviors. The most common tactic was to undulate the disc margins close to, or on, the bottom and thus stirring the substrate and uncovering hidden preys. Another tactic was to charge upon prey concentrated in the shallows. The least common tactic was to pick out prey adhered to the substrate. The first tactic is widespread in several species of marine rays in the Dasyatidae, whereas the remainder (especially picking up prey on substrata above water surface) may be restricted to the Potamotrygonidae.

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Barragán-Ramírez, José Luis, Benjamín Hernández, María Guadalupe Velarde-Aguilar, Oscar Pérez-Flores, José Luis Navarrete-Heredia, and Eduardo Pineda. "Feeding habits of Lithobates megapoda (Anura: Ranidae), a threatened leopard frog used for human consumption, in Lake Chapala, Mexico." Phyllomedusa: Journal of Herpetology 20, no. 1 (June 22, 2021): 75–88. http://dx.doi.org/10.11606/issn.2316-9079.v20i1p75-88.

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The Big-footed Leopard Frog (Lithobates megapoda) is a threatened and endemic species from western Mexico. This species has aquatic habits and it is distinguished by its large size, particularly by the length of its legs, reason for which it is captured for human consumption. Also, knowledge about its natural history is scarce and incomplete. In this study, we analyzed the composition of the diet of L. megapoda on the shore of Lake Chapala, the largest lake in Mexico. A total of 69 adult individuals were collected lifeless in fishing nets, during the rainy season (June-October), of which 48 had stomach contents. A total of 96 prey items were identified, which correspond to 13 prey categories. Fish constituted the most dominant prey category in the diet in terms of number, volume, frequency of occurrence, and relative importance. No significant differences were found in the consumption by prey type (aquatic or terrestrial). However, the aquatic preys had a greater relative importance and were more voluminous than the terrestrial ones. The diversity of prey categories, in terms of prey volume, indicates males may have a higher dietary diversity than females, but we not evaluated possible bias. In addition, a significant effect was found in the interaction of size (SVL) of frogs with the average of prey volume. Females (that are larger than males) consumed prey within a wide volume range and, the larger they are, more voluminous are prey. In this way it is possible that intraspecific competition for trophic resources in the environment is reduced. This study helps us understand the trophic ecology of L. megapoda, a frog species that plays an important role in the food web where it lives, as a predator feeding on aquatic and terrestrial organisms.

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Escalera-Vázquez, Luis H., Omar Domínguez-Domínguez, Eduardo Molina-Domínguez, S. S. S. Sarma, and S. Nandini. "Determination of optimal prey for rearing tropical gar Atractosteus tropicus (Lepisosteiformes: Lepisosteidae)." Revista de Biología Tropical 66, no. 3 (July 4, 2018): 1018. http://dx.doi.org/10.15517/rbt.v66i3.30670.

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Larval feeding studies of both ornamental and consumable fish species are important for formulating successful management, and culture strategies for conservation purposes. In the present study, we evaluated prey selectivity for the tropical gar Atractosteus tropicus in the larval stage (first 8 weeks) using the zooplankton Artemia fransiscana, Daphnia pulex and Moina macrocopa as prey following the hypothesis that prey selection of the fish species is related not only to prey species preferences but to the difference in prey densities present in the environment. Functional responses were tested at prey densities of 0.2, 0.5, 1.0, 2.0, 4.0 and 8.0 ind. mL-1 and analyzed using Manly’s α. For prey selectivity, we used the three zooplankton species at three different densities. In these two experiments the fish larvae were allowed to feed for 45 min. To quantify feeding behavior (encounters, attacks, captures, ingestions, rejections) we used a density of 1 ind. mL-1 using each prey species based on 10 minutes of direct observation. Our results showed a functional response Type II for A. tropicus preying mostly on A. franciscana and M. macrocopa. The Manly’s α index showed that M. macrocopa and A. franciscana are the most preys selected. The values for encounters for the three prey species were relatively constant during the eight weeks. Encounter values for the cladocerans were low in comparison to A. franciscana; however, high success in capture and ingestion was observed for all prey species used. Our results from the functional response experiments supports the hypothesis that A. tropicus is an active predator presenting a functional response of a carnivorous fish and the shift in prey selection suggests that even at low prey availability, A. tropicus is able to manipulate and feed on zooplankton of wide range in size. Also, according to our results, we suggest the use of a mix of A. franciscana and M. macrocopa to feed A. tropicus in culture systems in concentrations ≈ 2 ind. mL-1 during the first 3 weeks of age and then shift to M. macrocopa from the 4 week. Our results, in conjunction with studies on the survivorship of the juveniles would aid in conservation efforts and improve the production of gars in aquaculture.

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Hahn, Norma Segatti, Rosilene Luciana Delariva, and Valdirene Esgarbosa Loureiro. "Feeding of Acestrorhynchus lacustris (Characidae): a post impoundment studies on Itaipu reservoir, upper Paraná River, PR." Brazilian Archives of Biology and Technology 43, no. 2 (2000): 207–13. http://dx.doi.org/10.1590/s1516-89132000000200010.

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With objective to know feeding spectrum of Acestrorhynchus lacustris (Reinhardt, 1874), a middle size predator in different places of influence area of Itaipu reservoir, stomach contents were analyzed. Samples were collected from March 1984 to February 1989 from Itaipu Reservoir and its adjacent areas. Its fed mainly on fishes, but it was an opportunistic (consumed 17 species of prey). Despite of the wide feeding spectrum, few preys were dominant in the diet, according to the different habitats sampled. As a result, it significant spatial differences in the diet was observed. Was observed through "Detrented Correspondence Analysis" (DCA) these were divided into three groups in relation with diet: preys from upstream, with higher scores; preys from the reservoir, with intermediate scores; and preys from a tributary with smaller scores. This discrimination may be a function of prey availability in each habitat. The mean size of preys consumed increased with the size of the predator, as well as the variance, i. e. the largest fish also consumed small preys.

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Journal articles on the topic 'Prey'

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