Journal articles: 'Selective predation'

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Bijleveld, A. I., S. Twietmeyer, J. Piechocki, J. A. van Gils, and T. Piersma. "Selective Predation." Bulletin of the Ecological Society of America 96, no. 4 (October 2015): 639–43. http://dx.doi.org/10.1890/0012-9623-96.4.639.

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ALAM, SHARIFUL. "RISK OF DISEASE-SELECTIVE PREDATION IN AN INFECTED PREY-PREDATOR SYSTEM." Journal of Biological Systems 17, no. 01 (March 2009): 111–24. http://dx.doi.org/10.1142/s0218339009002703.

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In this paper the mathematical model of disease-selective predation as proposed by Roy and Chattopadhyay10 is considered to identify the true risk of selective predation where the predator can recognize the infected prey and avoids those during predation. Furthermore, the model is modified by adding a discrete time delay in the term involving the gestation of prey by the predator and analyzed both numerically and analytically to review the risk factors.

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Kelley, Patricia H. "Apparent cannibalism by Chesapeake Group naticid gastropods: a predictable result of selective predation." Journal of Paleontology 65, no. 1 (January 1991): 75–79. http://dx.doi.org/10.1017/s0022336000020229.

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Naticid gastropods of the Chesapeake Group of Maryland, like extant naticids, apparently were cannibalistic. This cannibalism did not result from the absence of bivalve prey or from the ineptitude of the predator, as some previous authors have suggested. Instead, predation on Chesapeake Group naticids was a predictable result of prey selection to maximize energy gain per foraging time.This study examines predation onLunatia heros(530 specimens) andPolinices duplicatus(340 specimens) from the St. Marys Formation of the Chesapeake Group. Predation on naticids displayed the same characteristics as predation on bivalve prey, including selectivity of prey size and drillhole site. The two naticid species were differentially attacked, based on their relative cost-benefit ratios and escape sizes. Cannibalism is not anomalous; it is the expected result of selective predation, and is inhibited primarily by the high mobility of naticid prey.

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Elliott, J. K., and W. C. Leggett. "Influence of temperature on size-dependent predation by a fish (Gasterosteus aculeatus) and a jellyfish (Aurelia aurita) on larval capelin (Mallotus villosus)." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 12 (December 1, 1997): 2759–66. http://dx.doi.org/10.1139/f97-190.

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We compared the size-dependent mortality patterns of newly emerged larval capelin (Mallotus villosus) at three different temperatures (3, 9, and 15°C) when exposed to predation by threespine stickleback (Gasterosteus aculeatus) and moon jellyfish (Aurelia aurita). Controlled experiments were conducted in both microcosms (38 L) and mesocosms (3100 L). Some temperature-related trends were evident in experiments with sticklebacks, but not with jellyfish. Sticklebacks fed selectively on smaller capelin larvae at 15°C, were nonselective at 9°C, and fed on larger larvae at 3°C. There was no prey size selection by A. aurita at any of the temperatures examined. Our findings support the view that the direction and magnitude of size-selective predation vary depending on the predator-prey assemblage and environmental conditions examined.

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Post, John R., and Andrew B. Prankevicius. "Size-Selective Mortality in Young-of-the-Year Yellow Perch (Perca flavescens): Evidence from Otolith Microstructure." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 11 (November 1, 1987): 1840–47. http://dx.doi.org/10.1139/f87-228.

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Large body size and high growth rates can strongly influence the survival of larval and juvenile fish during periods of intense predation pressure. Experimental evidence suggests that piscivorous fish often feed size selectively, but direct field evidence of size-selective mortality and of the effect of rapid growth on the intensity of size-selective mortality is limited. We used the growth record from otolith microstructure to test the hypothesis that young-of-the-year yellow perch (Perca flavescens) that survived their first growing season were the larger and faster growing members of their cohort. Strong size-selective mortality was identified within the first growing season for a slowly growing population. During the same year, a faster growing population showed minimal size-selective mortality. In contrasting the two populations, differences in predator species composition confounded the growth rate size-selectivity relationship, but it was clear that size-selective predation could be intense, favouring the survival of the faster growing individuals within a population.

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Kinoshita, Hikari, Yasuhiro Kamimura, Ken-Ichiro Mizuno, and Jun Shoji. "Night-time predation on post-settlement Japanese black rockfish Sebastes cheni in a macroalgal bed: effect of body length on the predation rate." ICES Journal of Marine Science 71, no. 4 (July 19, 2013): 1022–29. http://dx.doi.org/10.1093/icesjms/fst033.

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Abstract Recent field studies have pointed out that the vulnerability of juvenile fish to predation is higher than anticipated during night-time in vegetated habitats. Effects of abundance, body length, and growth rate on predation were examined in juvenile Japanese black rockfish in 2009–2011 in a macroalgal bed. Juvenile rockfish abundance ranged between 2.5 and 49.0 ind. 100 m–2 and the biomass of potential predators (piscivorous fish >82.5 mm) between 140.0 and 601.3 g 100 m−2. Sebastes inermis was the most dominant predator, compromising more than 50% by wet weight on all sampling days. Comparison of the total length of juveniles surviving (as original population, OP) and that of juveniles ingested (IG) by predators provided the evidence of the size-selective predation on juvenile rockfish on three of seven sampling days. The juvenile predation rate estimated as abundance of IG (N 100 m−2)/(abundance of IG + OP (N 100 m−2)) × 100100 varied between 0.4 and 12.5%. Neither juvenile rockfish abundance nor predator biomass had a significant effect on the juvenile predation rate, whereas the juvenile body length had a significant effect, smaller individuals being more vulnerable to predation. The growth-selective predation was not detected. Macroalgal habitats, although functioning as nurseries during the day, may contribute as feeding grounds for piscivorous fish predators at night leading to enhanced nocturnal predation rates.

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Mace, Marvin M., and Lawrence P. Rozas. "Fish Predation on Juvenile Penaeid Shrimp: Examining Relative Predator Impact and Size-Selective Predation." Estuaries and Coasts 41, no. 7 (May 10, 2018): 2128–34. http://dx.doi.org/10.1007/s12237-018-0409-4.

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Olson, Randal S., David B. Knoester, and Christoph Adami. "Evolution of Swarming Behavior Is Shaped by How Predators Attack." Artificial Life 22, no. 3 (August 2016): 299–318. http://dx.doi.org/10.1162/artl_a_00206.

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Animal grouping behaviors have been widely studied due to their implications for understanding social intelligence, collective cognition, and potential applications in engineering, artificial intelligence, and robotics. An important biological aspect of these studies is discerning which selection pressures favor the evolution of grouping behavior. In the past decade, researchers have begun using evolutionary computation to study the evolutionary effects of these selection pressures in predator-prey models. The selfish herd hypothesis states that concentrated groups arise because prey selfishly attempt to place their conspecifics between themselves and the predator, thus causing an endless cycle of movement toward the center of the group. Using an evolutionary model of a predator-prey system, we show that how predators attack is critical to the evolution of the selfish herd. Following this discovery, we show that density-dependent predation provides an abstraction of Hamilton's original formulation of domains of danger. Finally, we verify that density-dependent predation provides a sufficient selective advantage for prey to evolve the selfish herd in response to predation by coevolving predators. Thus, our work corroborates Hamilton's selfish herd hypothesis in a digital evolutionary model, refines the assumptions of the selfish herd hypothesis, and generalizes the domain of danger concept to density-dependent predation.

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Heurich, Marco, Klara Zeis, Helmut Küchenhoff, Jörg Müller, Elisa Belotti, Luděk Bufka, and Benno Woelfing. "Selective Predation of a Stalking Predator on Ungulate Prey." PLOS ONE 11, no. 8 (August 22, 2016): e0158449. http://dx.doi.org/10.1371/journal.pone.0158449.

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Carter, Mauricio J., Martin I. Lind, Stuart R. Dennis, William Hentley, and Andrew P. Beckerman. "Evolution of a predator-induced, nonlinear reaction norm." Proceedings of the Royal Society B: Biological Sciences 284, no. 1861 (August 23, 2017): 20170859. http://dx.doi.org/10.1098/rspb.2017.0859.

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Inducible, anti-predator traits are a classic example of phenotypic plasticity. Their evolutionary dynamics depend on their genetic basis, the historical pattern of predation risk that populations have experienced and current selection gradients. When populations experience predators with contrasting hunting strategies and size preferences, theory suggests contrasting micro-evolutionary responses to selection. Daphnia pulex is an ideal species to explore the micro-evolutionary response of anti-predator traits because they face heterogeneous predation regimes, sometimes experiencing only invertebrate midge predators and other times experiencing vertebrate fish and invertebrate midge predators. We explored plausible patterns of adaptive evolution of a predator-induced morphological reaction norm. We combined estimates of selection gradients that characterize the various habitats that D. pulex experiences with detail on the quantitative genetic architecture of inducible morphological defences. Our data reveal a fine scale description of daphnid defensive reaction norms, and a strong covariance between the sensitivity to cues and the maximum response to cues. By analysing the response of the reaction norm to plausible, predator-specific selection gradients, we show how in the context of this covariance, micro-evolution may be more uniform than predicted from size-selective predation theory. Our results show how covariance between the sensitivity to cues and the maximum response to cues for morphological defence can shape the evolutionary trajectory of predator-induced defences in D. pulex .

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Noonan, Brice P., and Aaron A. Comeault. "The role of predator selection on polymorphic aposematic poison frogs." Biology Letters 5, no. 1 (November 18, 2008): 51–54. http://dx.doi.org/10.1098/rsbl.2008.0586.

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Demonstrations of interactions between diverse selective forces on bright coloration in defended species are rare. Recent work has suggested that not only do the bright colours of Neotropical poison frogs serve to deter predators, but they also play a role in sexual selection, with females preferring males similar to themselves. These studies report an interaction between the selective forces of mate choice and predation. However, evidence demonstrating phenotypic discrimination by potential predators on these polymorphic species is lacking. The possibility remains that visual (avian) predators possess an inherent avoidance of brightly coloured diurnal anurans and purifying selection against novel phenotypes within populations is due solely to non-random mating. Here, we examine the influence of predation on phenotypic variation in a polymorphic species of poison frog, Dendrobates tinctorius . Using clay models, we demonstrate a purifying role for predator selection, as brightly coloured novel forms are more likely to suffer an attack than both local aposematic and cryptic forms. Additionally, local aposematic forms are attacked, though infrequently, indicating ongoing testing/learning and a lack of innate avoidance. These results demonstrate predator-driven phenotypic purification within populations and suggest colour patterns of poison frogs may truly represent a ‘magic trait’.

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Meri, Taru, Matti Halonen, Tapio Mappes, and Jukka Suhonen. "Younger bank voles are more vulnerable to avian predation." Canadian Journal of Zoology 86, no. 9 (September 2008): 1074–78. http://dx.doi.org/10.1139/z08-087.

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The importance of predation on prey populations is mainly determined by the number of eaten prey. However, the total impact of predation might also be determined by the selection of certain prey individuals, e.g., different sexes or age categories. Here we tested selective predation by an avian predator, the pygmy owl ( Glaucidium passerinum (L., 1758)), on bank voles ( Myodes ( Clethrionomys ) glareolus (Schreber, 1780)). We compared the sex, age, and mass of hoarded prey with the animals snap-trapped from the field. There were no differences in the sex ratio between hoarded bank voles and those available in the field. However, hoarded voles were significantly younger than ones in the field sample. There was no statistically significant difference in mass between animals from larders and from the field. We suggest that the greater vulnerability of younger animals to predation might be due to their higher activity, or alternatively, they might be forced to forage in less safe habitats.

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Dingemanse, Niels J., Fons Van der Plas, Jonathan Wright, Denis Réale, Maarten Schrama, Derek A. Roff, Els Van der Zee, and Iain Barber. "Individual experience and evolutionary history of predation affect expression of heritable variation in fish personality and morphology." Proceedings of the Royal Society B: Biological Sciences 276, no. 1660 (January 6, 2009): 1285–93. http://dx.doi.org/10.1098/rspb.2008.1555.

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Predation plays a central role in evolutionary processes, but little is known about how predators affect the expression of heritable variation, restricting our ability to predict evolutionary effects of predation. We reared families of three-spined stickleback Gasterosteus aculeatus from two populations—one with a history of fish predation (predator sympatric) and one without (predator naive)—and experimentally manipulated experience of predators during ontogeny. For a suite of ecologically relevant behavioural (‘personality’) and morphological traits, we then estimated two key variance components, additive genetic variance ( V A ) and residual variance ( V R ), that jointly shape narrow-sense heritability ( h 2 = V A /( V A + V R )). Both population and treatment differentially affected V A versus V R , hence h 2 , but only for certain traits. The predator-naive population generally had lower V A and h 2 values than the predator-sympatric population for personality behaviours, but not morphological traits. Values of V R and h 2 were increased for some, but decreased for other personality traits in the predator-exposed treatment. For some personality traits, V A and h 2 values were affected by treatment in the predator-naive population, but not in the predator-sympatric population, implying that the latter harboured less genetic variation for behavioural plasticity. Replication and experimental manipulation of predation regime are now needed to confirm that these population differences were related to variation in predator-induced selection. Cross-environment genetic correlations ( r A ) were tight for most traits, suggesting that predator-induced selection can affect the evolution of the same trait expressed in the absence of predators. The treatment effects on variance components imply that predators can affect evolution, not only by acting directly as selective agents, but also by influencing the expression of heritable variation.

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Boukal, David S., Luděk Berec, and Vlastimil Křivan. "Does Sex-Selective Predation Stabilize or Destabilize Predator-Prey Dynamics?" PLoS ONE 3, no. 7 (July 16, 2008): e2687. http://dx.doi.org/10.1371/journal.pone.0002687.

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Gourbiere, Sébastien, Pierre Auger, Jean Luc Chassé, and Bruno Faivre. "Extinction Waves in Spatial Population Dynamic Models — the Case of two Sibling Bird Species H. Icterina and H. Polygotta." Journal of Biological Systems 05, no. 03 (September 1997): 359–74. http://dx.doi.org/10.1142/s0218339097000229.

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Two spatial models of populations dynamics are presented to study the evolution of spatial distributions of two sibling species. We defined firstly an interspecific competition model and secondly a one predator-two preys model. They are constituted of a two dimensional discrete set of cells.Initially, the two competing or prey species occupy two complementary areas with common zone and the predator is regularly distributed. Populations of each cell are assumed to firstly have local interactions of competition or selective predation and secondly disperse to the four nearest neighbouring cells. We establish a typology of spatial structures obtained from both interspecific competition and selective predation. These two types of interactions are able to create a sympatric zone and to cause its motion.

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Kulatska, Nataliia, Pamela J. Woods, Bjarki Þór Elvarsson, and Valerio Bartolino. "Size-selective competition between cod and pelagic fisheries for prey." ICES Journal of Marine Science 78, no. 5 (June 1, 2021): 1872–86. http://dx.doi.org/10.1093/icesjms/fsab094.

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Abstract Predators often predate on a limited size range of prey, which may or may not overlap with size ranges of same prey targeted by fisheries. When they do overlap, the effect of competition over that prey is immediate, as the predator removes prey, which are at the same time suitable for the fishery. However, if the predator consumes the same prey species as the fishery, but targets smaller prey sizes, this predation on smaller sizes may result in a potential loss of future, rather than current, fishing opportunities. Comparative analyses of predator size preference and fisheries selectivity are scarce, despite their relevance in the context of integrated management of fish populations. We evaluated how size-selective cod predation influences the dynamics of sprat and herring in the Baltic Sea, as well as the competition with pelagic fisheries through immediate and delayed effects. We found a large overlap (30–60%) between prey lengths targeted by cod and fisheries, which was largest in the 1970s–1980s, when cod had higher abundance and was larger in size. Cod generally consumes herring and sprat, which are smaller than those caught by the fisheries, causing both immediate and delayed effects on prey biomass available for the fisheries.

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Parker, Michael S. "Size-selective predation on benthic macroinvertebrates by stream-dwelling salamander larvae." Archiv für Hydrobiologie 128, no. 4 (November 11, 1993): 385–400. http://dx.doi.org/10.1127/archiv-hydrobiol/128/1993/385.

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Roy, Tamal, and Robert Arlinghaus. "Size-selective mortality fosters ontogenetic changes in collective risk-taking behaviour in zebrafish, Danio rerio." Oecologia 200, no. 1-2 (October 2022): 89–106. http://dx.doi.org/10.1007/s00442-022-05256-y.

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AbstractSize-selective mortality is common in fish populations and can operate either in a positive size-selective fashion by harvesting larger-than-average fish or be negatively size-selective by harvesting smaller-than-average fish. Through various mechanisms (like genetic correlations among behaviour and life-history traits or direct selection on behaviour co-varying with growth rate or size-at-maturation), size-selection can result in evolutionary changes in behavioural traits. Theory suggests that both positive and negative size-selection without additional selection on behaviour favours boldness, while evolution of shyness is possible if the largest fish are harvested. Here we examined the impact of size-selective mortality on collective boldness across ontogeny using three experimental lines of zebrafish (Daniorerio) generated through positive (large-harvested), negative (small-harvested) and random (control line) size-selective mortality for five generations and then relaxed selection for 10 generations to examine evolutionarily fixed outcomes. We measured collective risk-taking during feeding (boldness) under simulated aerial predation threat, and across four contexts in presence/absence of a cichlid. Boldness decreased across ontogeny under aerial predation threat, and the small-harvested line was consistently bolder than controls. The large and small-harvested lines showed higher behavioural plasticity as larvae and developed personality earlier compared to the controls. The large-harvested line showed increased variability and plasticity in boldness throughout ontogeny. In the presence of a live predator, fish did not differ in boldness in three contexts compared to the controls, but the large-harvested line showed reduced behavioural plasticity across contexts than controls. Our results confirmed theory by demonstrating that size-selective harvesting evolutionarily alters collective boldness and its variability and plasticity.

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Takasuka, A., I. Aoki, and Y. Oozeki. "Predator-specific growth-selective predation on larval Japanese anchovy Engraulis japonicus." Marine Ecology Progress Series 350 (November 22, 2007): 99–107. http://dx.doi.org/10.3354/meps07158.

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Walsh, Matthew R., and David M. Post. "Interpopulation variation in a fish predator drives evolutionary divergence in prey in lakes." Proceedings of the Royal Society B: Biological Sciences 278, no. 1718 (January 26, 2011): 2628–37. http://dx.doi.org/10.1098/rspb.2010.2634.

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Ecological factors are known to cause evolutionary diversification. Recent work has shown that evolution in strongly interacting predator species has reciprocal impacts on ecosystems. These divergent impacts of predators may alter the selective landscape and cause the evolution of prey. Yet, this link between intraspecific variation and evolution is unexplored. We compared the life history of a species of zooplankton ( Daphnia ambigua ) from lakes in New England in which the dominant planktivorous predator, the alewife ( Alosa pseudoharengus ), differs in feeding traits and migratory behaviour. Anadromous alewife (seasonal migrants) exhibit larger gapes, gill-raker spacing and target larger prey than landlocked alewife (year-round freshwater resident). In ‘anadromous’ lakes, Daphnia are abundant in the spring but extirpated by alewife predation in summer. Daphnia are rare year-round in ‘landlocked’ lakes. We show that Daphnia from lakes with anadromous alewife grew faster, matured earlier but at the same size and produced more offspring than Daphnia from lakes with landlocked or no alewife across multiple temperature and resource treatments. Our results are inconsistent with a response to size-selective predation but are better explained as an adaptation to colder temperatures and shorter periods of development (countergradient variation) mediated by seasonal alewife predation.

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Hoogland, John L., Kristin E. Cannon, Lili M. DeBarbieri, and Theodore G. Manno. "Selective Predation on Utah Prairie Dogs." American Naturalist 168, no. 4 (October 2006): 546–52. http://dx.doi.org/10.1086/507714.

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Paradis, A. R., M. Pépin, and P. Pepin. "Disentangling the effects of size-dependent encounter and susceptibility to predation with an individual-based model for fish larvae." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 9 (September 1, 1999): 1562–75. http://dx.doi.org/10.1139/f99-080.

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We investigated the effects of size-dependent encounter and susceptibility, the role of variation in the size distribution of predators, and the timing of prey-predator interaction during the larval phase in shaping the length frequency distribution of surviving fish larvae. These analyses based on general empirical size-dependent relationships may have broad implications in understanding larval fish cohort dynamics. We demonstrated that the formulations of encounter and susceptibility to predation counteract each other, an increased range of predator sizes reduces only slightly the evidence for size-selective mortality, and synchronous spawning and hatching events have the potential to yield strong size-selective mortality of a cohort of fish larvae. The important factors in generating size-selective mortality are either the timing of encounters between fish larvae and their predators or high mortality rates. We demonstrated a direct relationship between the potential of size-selective mortality and the overall mortality rate of the cohort. We suggest that it may be difficult to detect the effect of size-dependent processes in the field. A better understanding of the factors influencing encounter represents a critical element in extrapolating laboratory studies of predation to the field.

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MARTINELLI, JULIETA C., MATTHEW A. KOSNIK, and JOSHUA S. MADIN. "ENCOUNTER FREQUENCY DOES NOT PREDICT PREDATION FREQUENCY IN TROPICAL DEAD-SHELL ASSEMBLAGES." PALAIOS 30, no. 12 (December 1, 2015): 818–26. http://dx.doi.org/10.2110/palo.2015.039.

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Abstract Predation is frequently suggested to be a key biotic process that can shape ecological communities and drive coevolution. The premise behind these hypotheses is that predators select prey to ensure maximum gain per unit effort; for example, by selecting species that are more abundant or accessible. In this study, we tested for predator selectivity in a tropical molluscan assemblage by quantifying the influence of relative abundance (encounter frequency) on predation frequencies. We collected macromollusks (> 4 mm) from 15 sites in three soft-sediment reef lagoons at One Tree Reef (southern Great Barrier Reef, Australia). Dead mollusks were counted and identified to species level (61 species, n = 8131), and species predation frequencies were calculated as the proportion of shells with drill holes. We found that in this infauna-dominated community, levels of drilling predation were low (7.14% on average), and there was no evidence that predators selected prey based on encounter frequency. This result was consistent across prey species and lagoons. Thus, drilling predators did not specialize on more accessible prey species and were not a major cause of mortality in this modern macromollusk assemblage. Since drilling gastropods are size selective, lack of selectivity in our samples only applies to the prey size range considered. Detailed studies of prey morphological traits, as well as accounting for predator non-consumptive effects could shed light on the preferences and relevance of drilling gastropods in this soft-sediment carbonate reef assemblage.

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Hershey, Anne E. "Selective Predation by Procladius in an Arctic Alaskan Lake." Canadian Journal of Fisheries and Aquatic Sciences 43, no. 12 (December 1, 1986): 2523–28. http://dx.doi.org/10.1139/f86-312.

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In arctic Alaskan Toolik Lake, the predatory larval chironomid Procladius spp. (Diptera) feeds on a variety of benthic organisms including algae, other chironomids, and microcrustaceans. Laboratory experiments with two similar-sized chironomid prey, instar I Chironomus and instar II Paratanytarsus, showed that Procladius was a more effective predator on Chironomus. The two prey used different foraging behaviors; Chironomus grazed an area around its tube but Paratanytarsus remained inside its tube. In a field experiment, in which Procladius density was manipulated, a decrease in prey density occurred in the chironomid group Orthocladiinae, which could be attributed to Procladius predation. Gut analyses of Procladius showed that a higher proportion of Orthocladiinae was eaten than could be predicted from their abundance. Orthocladiinae, which typically graze around tubes, may have been more susceptible to Procladius because of behavioral characteristics.

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Sand, Håkan, Camilla Wikenros, Petter Wabakken, and Olof Liberg. "Cross-continental differences in patterns of predation: will naive moose in Scandinavia ever learn?" Proceedings of the Royal Society B: Biological Sciences 273, no. 1592 (February 16, 2006): 1421–27. http://dx.doi.org/10.1098/rspb.2005.3447.

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Predation has been recognized as a major selective force in the evolution of behavioural characteristics of mammals. As a consequence of local predator extinction, prey may lose knowledge about natural predators but usually express behavioural adjustments after return of predators. Human harvest may replace natural predation but prey selection may differ from that of natural predators leading to a change in the behavioural response of prey. We show that hunting success (HS) of re-colonizing wolves ( Canis lupus ) on moose ( Alces alces ) in Scandinavia was higher than reported in North America, where moose have been continuously exposed to wolves and grizzly bears. We found no evidence that moose expressed behavioural adjustments that lowered the HS of wolves in territories that had been occupied by wolves for up to 21 years. Moose behaviour towards wolves and humans typically differs in Scandinavia compared to North America. We explain the differences found to be caused by variation in predation pressure by large carnivores and the rate, and mode, of human harvest during the twentieth century.

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Debes, Paul V., and Jeffrey A. Hutchings. "Effects of domestication on parr maturity, growth, and vulnerability to predation in Atlantic salmon." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 9 (September 2014): 1371–84. http://dx.doi.org/10.1139/cjfas-2013-0618.

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Domestication can change fitness-related traits. We investigated domestication-induced changes in fitness-related traits in Atlantic salmon (Salmo salar) under naturally enriched laboratory conditions with and without threat of predation. Selection in two strains for rapid growth for three and five generations resulted in two and three times larger sizes of under-yearling parr relative to their wild ancestor. An initially larger size and ability to outgrow prey size more rapidly resulted in lower size-selective predation mortality for domesticated individuals. Growth under threat of predation was only reduced for wild individuals, suggesting that domestication co-selects for predator-related stress resistance. Size-adjusted male parr maturation probability was 34% in the wild strain, but significantly reduced to 10% and 7% after three and five generations of domestication, respectively. Together, freshwater-stage-specific survival for individuals with a domesticated background relative to individuals with a wild genetic background might be higher in the presence of gape-limited predators preferring small individuals, but male reproductive success might be lower for domesticated individuals as their reproduction potential during the freshwater phase is reduced.

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Zhang, Shuaibing, Ruchira Mukherji, Somak Chowdhury, Lisa Reimer, and Pierre Stallforth. "Lipopeptide-mediated bacterial interaction enables cooperative predator defense." Proceedings of the National Academy of Sciences 118, no. 6 (February 1, 2021): e2013759118. http://dx.doi.org/10.1073/pnas.2013759118.

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Bacteria are inherently social organisms whose actions should ideally be studied within an interactive ecological context. We show that the exchange and modification of natural products enables two unrelated bacteria to defend themselves against a common predator. Amoebal predation is a major cause of death in soil bacteria and thus it exerts a strong selective pressure to evolve defensive strategies. A systematic analysis of binary combinations of coisolated bacteria revealed strains that were individually susceptible to predation but together killed their predator. This cooperative defense relies on a Pseudomonas species producing syringafactin, a lipopeptide, which induces the production of peptidases in a Paenibacillus strain. These peptidases then degrade the innocuous syringafactin into compounds, which kill the predator. A combination of bioprospecting, coculture experiments, genome modification, and transcriptomics unravel this novel natural product-based defense strategy.

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Plirú, Antonio, Jeroen van der Kooij, Georg H. Engelhard, Clive J. Fox, Stephen P. Milligan, and Ewan Hunter. "Sprat feeding behaviour, selective predation, and impact on plaice egg mortality." ICES Journal of Marine Science 69, no. 6 (July 1, 2012): 1019–29. http://dx.doi.org/10.1093/icesjms/fss081.

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Abstract Plirú, A., van der Kooij, J., Engelhard, G. H., Fox, C. J., Milligan, S. P., and Hunter, E. 2012. Sprat feeding behaviour, selective predation, and impact on plaice egg mortality. – ICES Journal of Marine Science, 69: 1019–1029. Although the causes of fish egg and larval mortality are poorly understood, predation is thought to be a major contributing factor. The feeding behaviour of sprat at a plaice spawning ground in the Irish Sea during February 2009 is described and their contribution to plaice egg mortality investigated. Acoustic observations and analysis of stomach contents revealed diel behaviour, with dense schools associated with feeding formed during daylight dispersing into thinly spread aggregations at dusk. Of 338 stomachs analysed, 95% contained identifiable prey items. Feeding activity peaked between 10:00 and 18:00, for all food groups. Numerically, gadoid eggs were the most frequently consumed prey (64%), followed by copepods (25%) and plaice eggs (7%). Plaice eggs were present in 91% of the stomachs analysed. Converting stomach content data to daily consumption suggested that sprat may consume 73% of all plaice eggs spawned in the area. Predation by sprat appears to account for a large proportion of plaice egg mortality, so the abundance and distribution of this pelagic predator may have important consequences for the recruitment dynamics of other fish species. Moreover, fish eggs may be an important energy source for sprat during late winter, when alternative prey is scarce.

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Arce, Elsah, and Guillermina Alcaraz. "Plasticity of shell preference and its antipredatory advantages in the hermit crab Calcinus californiensis." Canadian Journal of Zoology 91, no. 5 (May 2013): 321–27. http://dx.doi.org/10.1139/cjz-2012-0310.

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The preference of the hermit crab Calcinus californiensis Bouvier, 1898 among six shell species and different shell sizes was evaluated in the presence of the swimming crab Arenaeus mexicanus (Gerstaecker, 1856), a natural predator of this species. In a second experiment, the survival benefit of the shell choice made under predation threat was examined by exposing hermit crabs occupying three different shell species (including the most and least preferred shells of two fits) to a free swimming crab predator. The preference for shell species was similar in the absence and presence of the predator threat, although the hermit crabs choose larger shells (loose) when exposed to the predator compared with the ones chosen in its absence. The predatory experiment showed a higher survival chance for the hermit crabs occupying loose shells of the preferred shell species (Cantharus sanguinolentus (Duclos, 1833)). The results of this study show that the hermit crab C. californiensis is able to change their preference for shell size in response to a predation threat and that the change in preference confers survival benefits for hermit crabs. This study is consistent with the assumption that predation is an important selective pressure for intertidal hermit crabs.

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Strydom, Zanri, Lauren J. Waller, Mark Brown, Hervé Fritz, Kevin Shaw, and Jan A. Venter. "Factors that influence Cape fur seal predation on Cape gannets at Lambert’s Bay, South Africa." PeerJ 10 (June 13, 2022): e13416. http://dx.doi.org/10.7717/peerj.13416.

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Seabird populations experience predation that can impact their breeding density and breeding success. The Cape gannet Morus capensis is endemic to the Benguela upwelling ecosystem and is classified as Endangered by the IUCN. They are affected by several threats, including predation by the Cape fur seal Arctocephalus pusillus pusillus. Many fledglings succumb to predation during their maiden flight across waters around the island. To curb predation, the selective culling of individual predatory seals was implemented in 2014, 2015, and 2018. Our first study objective was to determine if selective culling of Cape fur seals significantly reduced predation probability on Cape gannets. We tested whether predation probability in 2014, 2015, and 2018 was affected by fish biomass, gannet fledgling numbers, and/or the presence/absence of selective culling. Our second objective was to determine what led to fluctuations in Cape fur seal predation on Cape gannet fledglings between 2007 and 2018. We tested whether fish biomass and the amount of Cape gannet fledglings in the water affected predation probability on the fledglings. Results indicated that selective culling reduced predation within years. We found that with both increased fledgling numbers and increased fish biomass, seal predation probability was reduced. This suggests that a sustainable way to promote the conservation of Cape gannets would be to increase food availability for both the Cape fur seals and Cape gannets. Our findings, collectively with the global trend of the declining Cape gannet population and their endemism, provide reasons advocating for the conservation of the food resources of both the Cape fur seal and the Cape gannet in the Benguela system.

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Cook, L. M., B. S. Grant, I. J. Saccheri, and J. Mallet. "Selective bird predation on the peppered moth: the last experiment of Michael Majerus." Biology Letters 8, no. 4 (February 8, 2012): 609–12. http://dx.doi.org/10.1098/rsbl.2011.1136.

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Colour variation in the peppered moth Biston betularia was long accepted to be under strong natural selection. Melanics were believed to be fitter than pale morphs because of lower predation at daytime resting sites on dark, sooty bark. Melanics became common during the industrial revolution, but since 1970 there has been a rapid reversal, assumed to have been caused by predators selecting against melanics resting on today's less sooty bark. Recently, these classical explanations of melanism were attacked, and there has been general scepticism about birds as selective agents. Experiments and observations were accordingly carried out by Michael Majerus to address perceived weaknesses of earlier work. Unfortunately, he did not live to publish the results, which are analysed and presented here by the authors. Majerus released 4864 moths in his six-year experiment, the largest ever attempted for any similar study. There was strong differential bird predation against melanic peppered moths. Daily selection against melanics ( s ≃ 0.1) was sufficient in magnitude and direction to explain the recent rapid decline of melanism in post-industrial Britain. These data provide the most direct evidence yet to implicate camouflage and bird predation as the overriding explanation for the rise and fall of melanism in moths.

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McCormick, MI, and BA Kerrigan. "Predation and its influence on the condition of a newly settled tropical demersal fish." Marine and Freshwater Research 47, no. 3 (1996): 557. http://dx.doi.org/10.1071/mf9960557.

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The effects of predation by a common tropical piscivore on levels of variability in size and body composition of a demersal fish at settlement were examined in a series of laboratory experiments. Wild-caught, newly metamorphosed goatfish (Upeneus tragula) were placed in large tanks and subjected to predation by lizardfish (Synodus variegatus). Three trials failed to show an influence of predation on the size distribution of the newly settled prey. In a second experiment, mid-larval-phase goatfish were subjected to one of two feeding regimes; this resulted in two groups of metamorphs that differed markedly in biochemical composition (i.e. total lipid levels). Twenty fish from each treatment were randomly chosen, under the constraint of a similar mean size, and subjected to predation. Susceptibility of newly metamorphosed fish to predation by the lizardfish was independent of their initial biochemical composition. These results suggest that predation by this common tropical reef fish predator may be non-selective with respect to both size and body composition of U. tragula. Consequently, the high variability found in these body attributes at settlement may extend its influence into the juvenile population.

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Wong, C. K., and W. G. Sprules. "Size-Selective Feeding by the Predatory Copepod Epischura lacustris Forbes." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 1 (January 1, 1985): 189–93. http://dx.doi.org/10.1139/f85-024.

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Size-selective predation by Epischura lacustris on Bosmina longirostris was investigated in the field by comparing the size distributions of Bosmina available in the water column with the carapace sizes of killed Bosmina. While Epischura could consume the entire size range (0.2–0.4 mm) of Bosmina, smalt prey (0.2–0.25 mm) consistently constituted the greatest portion of the diet. For Bosmina, vulnerability depended on the rate of encounter with the predator and on the probability of ingestion by the predator. The frequencies of different-sized prey in the diet were partially predicted on the basis of their relative abundance weighted by their ingestion probabilities. The prediction could be improved if encounter rates were known.

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Loron, Corentin C., Robert H. Rainbird, Elizabeth C. Turner, J. Wilder Greenman, and Emmanuelle J. Javaux. "Implications of selective predation on the macroevolution of eukaryotes: evidence from Arctic Canada." Emerging Topics in Life Sciences 2, no. 2 (July 20, 2018): 247–55. http://dx.doi.org/10.1042/etls20170153.

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Existing paleontological data indicate marked eukaryote diversification in the Neoproterozoic, ca. 800 Ma, driven by predation pressure and various other biotic and abiotic factors. Although the eukaryotic record remains less diverse before that time, molecular clock estimates and earliest crown-group affiliated microfossils suggest that the diversification may have originated during the Mesoproterozoic. Within new assemblages of organic-walled microfossils from the ca. 1150 to 900 Ma lower Shaler Supergroup of Arctic Canada, numerous specimens from various taxa display circular and ovoid perforations on their walls, interpreted as probable traces of selective protist predation, 150–400 million years before their first reported incidence in the Neoproterozoic. Selective predation is a more complex behavior than phagotrophy, because it requires sensing and selection of prey followed by controlled lysis of the prey wall. The ca. 800 Ma eukaryotic diversification may have been more gradual than previously thought, beginning in the late Mesoproterozoic, as indicated by recently described microfossil assemblages, in parallel with the evolution of selective eukaryovory and the spreading of eukaryotic photosynthesis in marine environments.

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Takasuka, Akinori, Ayumu Sakai, and Ichiro Aoki. "Dynamics of growth-based survival mechanisms in Japanese anchovy (Engraulis japonicus) larvae." Canadian Journal of Fisheries and Aquatic Sciences 74, no. 6 (June 2017): 812–23. http://dx.doi.org/10.1139/cjfas-2016-0120.

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Three growth-based survival mechanisms were tested for multiple cohorts of Japanese anchovy (Engraulis japonicus) larvae in Sagami Bay. Through otolith microstructure analysis, growth trajectories and histories of samples of the survivors were compared with those of the original populations to examine size- and growth-selective mortality to test the “bigger is better” and “growth-selective predation” mechanisms, respectively. The effects of growth rates on the timing of metamorphosis were examined to test the “stage duration” mechanism. The bigger is better and growth-selective predation mechanisms were detected to be effective in two and six of eight seasonal cohorts, respectively. Results contrary to the bigger is better and growth-selective predation mechanisms were obtained from three and two of eight cohorts, respectively. The stage duration mechanism was evaluated to be effective for both of two cohorts that were testable. Overall, none of the three mechanisms were universally appropriate for all of the cohorts. The relative contributions of the three mechanisms were dynamic, although the growth-selective predation mechanism was identified to be the major one in anchovy larvae in the study site.

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Wu, Qinglong L., Jens Boenigk, and Martin W. Hahn. "Successful Predation of Filamentous Bacteria by a Nanoflagellate Challenges Current Models of Flagellate Bacterivory." Applied and Environmental Microbiology 70, no. 1 (January 2004): 332–39. http://dx.doi.org/10.1128/aem.70.1.332-339.2004.

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ABSTRACT Current models suggest that (i) filamentous bacteria are protected against predation by nanoflagellates, (ii) prey size is positively correlated with prey-predator contact probability, and (iii) contact probability is mainly responsible for size-selective predation by interception-feeding flagellates. We used five strains of filamentous bacteria and one bacterivorous nanoflagellate, Ochromonas sp. strain DS, to test these assumptions. The five strains, including one spirochete and four Betaproteobacteria strains, were isolated by the filtration-acclimatization method. All five strains possess flexible cells, but they differ in average cell length, which ranged from 4.5 to 13.7 μm. High-resolution video microscopy was used to measure contact, capture, and ingestion rates, as well as selectivity of the flagellate feeding. Growth and feeding experiments with satiating and nonsatiating food conditions, as well as experiments including alternative well-edible prey, were performed. In contrast to predictions by current models, the flagellate successfully consumed all the tested filamentous strains. The ingestion rate was negatively correlated with bacterial length. On the other hand, the lengths of the filamentous bacteria were not positively correlated to the contact rate and capture rate but were negatively correlated to ingestion efficiency. In experiments including alternative nonfilamentous prey, the flagellates showed negative selection for filamentous bacteria, which was independent of food concentration and is interpreted as a passive selection. Our observations indicate that (i) size alone is not sufficient to define a refuge for filamentous bacteria from nanoflagellate predation and (ii) for the investigated filamentous bacteria, prey-predator contact probability could be more influenced by factors other than the prey size.

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Pepin, P., S. Pearre jr., and J. A. Koslow. "Predation on Larval Fish by Atlantic Mackerel Scomber scombrus, with a Comparison of Predation by Zooplankton." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 11 (November 1, 1987): 2012–18. http://dx.doi.org/10.1139/f87-247.

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This study reports on the feeding selectivity of Atlantic mackerel, Scomber scombrus, on larval fish (3-10 mm in length) presented as part of natural zooplankton assemblages. As with other vertebrate planktivores, prey preference was positively size selective, contrary to the pattern observed for several invertebrate carnivores. Larval fish density did not significantly influence predation rates. Furthermore, there was no evidence of either switching or saturation of the predator's functional feeding response with changes in alternative prey abundance, again unlike invertebrate predators. A review of previous experiments revealed that capture success of larval fish by predators is a function of the size of larval fish relative to the size of the predator, independent of predator taxa (i.e. vertebrate versus invertebrate).

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Johnsson, Jörgen I., Johan Höjesjö, and Ian A. Fleming. "Behavioural and heart rate responses to predation risk in wild and domesticated Atlantic salmon." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 4 (April 1, 2001): 788–94. http://dx.doi.org/10.1139/f01-025.

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Artificial culture may relax the selective pressures from predators, thereby altering behavioural and heart rate responses to predation risk. Culture may also impose new selection that adapts fish to confinement. Predictions from these hypotheses were tested by comparing seventh-generation farm Atlantic salmon (Salmo salar) with wild Atlantic salmon from the principal founder population of the farm strain. Wild age 1+ salmon had higher standard heart rates and showed a more pronounced flight and heart rate response to a simulated predator attack than did farmed salmon. However, wild fish were closer to the model predator at attack, which may have accentuated these differences. Both strains habituated to the threat, showing less response to the second attack than to the first. In contrast with age 1+ fish, wild age 2+ salmon had lower standard heart rates than farmed fish. Moreover, in age 2+ salmon, domestication effects were less clear and the response to predation threat considerably weaker, suggesting that environmental effects of culture override genetic effects as time in captivity increases. Domestication selection may thus alter reaction norms of farmed animals over environmental gradients and time. This should be considered when attempting to predict the consequences of release or escape of domesticated animals in the wild.

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Fennie, HW, S. Sponaugle, EA Daly, and RD Brodeur. "Prey tell: what quillback rockfish early life history traits reveal about their survival in encounters with juvenile coho salmon." Marine Ecology Progress Series 650 (September 17, 2020): 7–18. http://dx.doi.org/10.3354/meps13300.

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Predation is a major source of mortality in the early life stages of fishes and a driving force in shaping fish populations. Theoretical, modeling, and laboratory studies have generated hypotheses that larval fish size, age, growth rate, and development rate affect their susceptibility to predation. Empirical data on predator selection in the wild are challenging to obtain, and most selective mortality studies must repeatedly sample populations of survivors to indirectly examine survivorship. While valuable on a population scale, these approaches can obscure selection by particular predators. In May 2018, along the coast of Washington, USA, we simultaneously collected juvenile quillback rockfish Sebastes maliger from both the environment and the stomachs of juvenile coho salmon Oncorhynchus kisutch. We used otolith microstructure analysis to examine whether juvenile coho salmon were age-, size-, and/or growth-selective predators of juvenile quillback rockfish. Our results indicate that juvenile rockfish consumed by salmon were significantly smaller, slower growing at capture, and younger than surviving (unconsumed) juvenile rockfish, providing direct evidence that juvenile coho salmon are selective predators on juvenile quillback rockfish. These differences in early life history traits between consumed and surviving rockfish are related to timing of parturition and the environmental conditions larval rockfish experienced, suggesting that maternal effects may substantially influence survival at this stage. Our results demonstrate that variability in timing of parturition and sea surface temperature leads to tradeoffs in early life history traits between growth in the larval stage and survival when encountering predators in the pelagic juvenile stage.

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Ruggerone, Gregory T., Renn Hanson, and Donald E. Rogers. "Selective predation by brown bears (Ursus arctos) foraging on spawning sockeye salmon (Oncorhynchus nerka)." Canadian Journal of Zoology 78, no. 6 (June 1, 2000): 974–81. http://dx.doi.org/10.1139/z00-024.

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Selective predation by and predation rates of brown bears (Ursus arctos) foraging on spawning sockeye salmon (Oncorhynchus nerka) in a small shallow creek in the Wood River lake system near Bristol Bay, Alaska, were quantified during 1986 and 19901992. Bears killed a high proportion of spawning salmon when few salmon entered the creek (92% of 505 fish) and a much smaller proportion when the spawning population reached a historical high (16% of 15 631 fish). Selective predation on salmon that differed in length, sex, and spawning condition was measured by tagging salmon at the mouth of the creek immediately prior to upstream migration and then recovering dead tagged fish during daily surveys of the entire creek. The relative frequencies of large, medium-sized, and small salmon killed by bears indicated that the risk of predation was more than 150% greater for large than for small salmon. A higher proportion of the male salmon population was killed and a greater proportion of male bodies were consumed than female salmon. Selectivity for male salmon increased as the spawning season progressed, possibly because male salmon weakened earlier and lived longer in a weakened state than female salmon. Male salmon were attacked mostly along the dorsal hump area, whereas female salmon tended to be attacked along the abdomen, where eggs could be exposed. Bears selectively killed female salmon prior to spawning during 1 of the 3 years, but only 6.17.8% of the female spawning populations were killed prior to spawning. These data support the hypothesis that selective predation by bears may influence the body morphology of spawning salmon.

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Ivan, Lori N., and Tomas O. Höök. "Energy allocation strategies of young temperate fish: an eco-genetic modeling approach." Canadian Journal of Fisheries and Aquatic Sciences 72, no. 8 (August 2015): 1243–58. http://dx.doi.org/10.1139/cjfas-2014-0197.

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We use an individual-based eco-genetic model to explore the relative selective pressures of size-dependent predation, overwinter mortality, and density-dependent energy acquisition in structuring plastic and adaptive energy allocation during the first year of life of a temperate fish population. While several patterns emerging from a suite of eco-genetic model simulations were consistent with past theoretical models and empirical evaluations of energy allocation by young fishes, results also highlight the utility of eco-genetic models for simultaneous consideration of plastic and adaptive processes. Across simulations, variation in genetic control of energy allocation was limited during very early ontogeny when size-dependent predation pressure was particularly high. While this stabilizing selection on energy allocation diminished later in the growing season, predation, overwinter mortality, and density-dependent processes simultaneously structured energy partitioning later in ontogeny through the interactive influence of plastic and adaptive processes. Specifically, high risk of overwinter mortality and low predation selected for high prioritization of energy storage. We suggest that simulations demonstrate the utility of eco-genetic models for generating null predictions of how selective pressures may structure expression of life history traits, such as early life energy allocation.

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Gillis, H., B. Gauffre, R. Huot, and V. Bretagnolle. "Vegetation height and egg coloration differentially affect predation rate and overheating risk: an experimental test mimicking a ground-nesting bird." Canadian Journal of Zoology 90, no. 6 (June 2012): 694–703. http://dx.doi.org/10.1139/z2012-035.

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Avian eggs need to be laid in protected environments to develop and survive. Nest predation is known as the main cause of breeding failure for many birds, but nest microclimate conditions are also important for embryo development. These two selective pressures are particularly marked in ground-nesting birds. Vegetation height has been shown to be a critical factor for nest-site selection in ground-nesting birds because it can counteract predation and overheating simultaneously. It is therefore difficult to disentangle the respective influences of these risks on selection of a particular nest vegetation height. To develop a conceptual framework for understanding and predicting the relative effects of vegetation on predation and nest microclimate during a breeding season, we used vegetation height to manipulate differentially these two risks. We therefore exposed artificial nests to a wide range of vegetation heights, replicated the experimental tests during spring, and manipulated egg color to estimate predation risk. We confirmed that tall vegetation is relevant to protect unattended eggs against both risks. Whereas predation risk is stable for a given vegetation height, overheating risk presents inter- and intra-seasonal variations. Therefore, over a breeding season, for a given vegetation height, the respective strengths of the two risks are unbalanced and depends on egg coloration. The breeding strategy of ground-nesting birds thus should have been shaped by both selective pressures, but the ultimate choice may depend on the species-specific laying dates and alternative behavioral strategies for protecting the clutch. This study provides new perspectives to investigate avian parental behaviour.

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Kraemer, A. C., C. W. Philip, A. M. Rankin, and C. E. Parent. "Trade-offs direct the evolution of coloration in Galápagos land snails." Proceedings of the Royal Society B: Biological Sciences 286, no. 1894 (January 9, 2019): 20182278. http://dx.doi.org/10.1098/rspb.2018.2278.

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Increasingly, multiple selective factors are recognized as jointly contributing to the evolution of morphology. What is not clear is how these forces vary across communities to promote morphological diversification among related species. In this study of Galápagos endemic snails (genus Naesiotus ), we test several hypotheses of colour evolution. We observe mockingbirds (genus Mimus ) predating live snails and find that avian predation selects against conspicuous shells. The evolutionary outcome of this selection is a diversity of shell colours across snails of the archipelago, each closely matching local backgrounds. We also find that snails more regularly exposed to the hot, equatorial sun reflect more light than shells of species from shadier habitats, suggesting a role for thermoregulatory constraints directing colour evolution. The signature of thermoregulatory selection is most clear in comparatively young communities (on the youngest islands), while the signature of selection from predators is most evident in older communities (on the older islands). Together, our findings point to a scenario of shifting selective forces along island ontogeny and community maturity that lead to the distribution of snail coloration we observe in Galápagos. Complex selective regimes such as these may have more responsibility for morphological diversity than is currently recognized.

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Catania, S. V. L., J. Koprivnikar, and S. J. McCauley. "Size-dependent predation alters interactions between parasites and predators." Canadian Journal of Zoology 94, no. 9 (September 2016): 631–35. http://dx.doi.org/10.1139/cjz-2016-0088.

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Increasing evidence indicates that parasites play an important role within many systems as prey for higher trophic levels. Predation on parasites can decrease their numbers and may affect host infection rates. Cercariae, a free-living infectious stage of trematode parasites, are abundant in freshwater systems and are directly consumed by a number of freshwater predators. However, few studies have tested whether predators exhibit a preference for cercariae when alternative prey are available or how these preferences vary across predator body sizes. We assessed whether dragonfly larvae (dot-tailed whiteface, Leucorrhinia intacta (Hagen, 1861)), top predators in freshwater systems without fish, foraged preferentially when presented with two prey types, cercariae and zooplankton, and whether foraging preferences changed across predator body size. Body size of larval dragonfly predators was found to be significantly, and negatively, related to the fraction of cercariae in the diet. Larger bodied dragonfly larvae shifted their diet choice from cercariae to zooplankton. Changes in foraging selectivity as body size increases across a predator’s ontogeny can alter the strength of predator–prey interactions. Further investigation into size-selective foraging on parasites may provide new insights into the effects of predation on parasite abundance and transmission in natural systems.

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Meiners, Scott J., and Edmund W. Stiles. "Selective Predation on the Seeds of Woody Plants." Journal of the Torrey Botanical Society 124, no. 1 (January 1997): 67. http://dx.doi.org/10.2307/2996599.

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Barbraud, Christophe. "Subspecies-Selective Predation of Snow Petrels by Skuas." Oikos 86, no. 2 (August 1999): 275. http://dx.doi.org/10.2307/3546445.

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Convey, Laurie E., John Mark Hanson, and William C. MacKay. "Size-Selective Predation on Unionid Clams by Muskrats." Journal of Wildlife Management 53, no. 3 (July 1989): 654. http://dx.doi.org/10.2307/3809191.

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Potter, Tamara I., Hayley J. Stannard, Aaron C. Greenville, and Christopher R. Dickman. "Understanding selective predation: Are energy and nutrients important?" PLOS ONE 13, no. 8 (August 8, 2018): e0201300. http://dx.doi.org/10.1371/journal.pone.0201300.

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TSOULARIS, A. "A SLOW REINFORCEMENT LEARNING SCHEME FOR SELECTIVE PREDATION." Journal of Biological Systems 15, no. 02 (June 2007): 109–21. http://dx.doi.org/10.1142/s0218339007002179.

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In this paper, we utilize a reinforcement learning model for a specialist predator preying upon two types of prey, the noxious models, which are abundant, and the palatable mimics, which are much rarer, in accord with the concept of Batesian mimicry. The latter type of prey resembles the models in appearance so as to derive some protection from the predator who must avoid the unpalatable models. We treat the predator as a slow learning automaton adopting a simple reinforcement learning strategy in order to increase its consumption of palatable prey and reduce the consumption of unpalatable ones. We assume a logistic growth for both models and mimics.

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Lescak, Emily A., and Frank A. von Hippel. "Selective predation of threespine stickleback by rainbow trout." Ecology of Freshwater Fish 20, no. 2 (March 14, 2011): 308–14. http://dx.doi.org/10.1111/j.1600-0633.2011.00497.x.

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Journal articles on the topic 'Selective predation'

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