| 1. |
- Cote, Julien, et al.
(author)
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Personality-dependent dispersal cancelled under predation risk
- 2013
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In: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 280:1773, s. 20132349-
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Journal article (peer-reviewed)abstract
- Dispersal is a fundamental life-history trait for many ecological processes. Recent studies suggest that dispersers, in comparison to residents, display various phenotypic specializations increasing their dispersal inclination or success. Among them, dispersers are believed to be consistently more bold, exploratory, asocial or aggressive than residents. These links between behavioural types and dispersal should vary with the cause of dispersal. However, with the exception of one study, personality-dependent dispersal has not been studied in contrasting environments. Here, we used mosquitofish (Gambusia affinis) to test whether personality-dependent dispersal varies with predation risk, a factor that should induce boldness or sociability-dependent dispersal. Corroborating previous studies, we found that dispersing mosquitofish are less social than non-dispersing fish when there was no predation risk. However, personality-dependent dispersal is negated under predation risk, dispersers having similar personality types to residents. Our results suggest that adaptive dispersal decisions could commonly depend on interactions between phenotypes and ecological contexts.
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| 2. |
- Cote, Julien, et al.
(author)
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Personality-dependent dispersal in the invasive mosquitofish : group composition matters
- 2011
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In: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 278:1712, s. 1670-1678
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Journal article (peer-reviewed)abstract
- Understanding/predicting ecological invasions is an important challenge in modern ecology because of their immense economical and ecological costs. Recent studies have revealed that within-species variation in behaviour (i.e. animal personality) can shed light on the invasion process. The general hypothesis is that individuals' personality type may affect their colonization success, suggesting that some individuals might be better invaders than others. We have recently shown that, in the invasive mosquitofish (Gambusia affinis), social personality trait was an important indicator of dispersal distance, with more asocial individuals dispersing further. Here, we tested how mean personality within a population, in addition to individual personality type, affect dispersal and settlement decisions in the mosquitofish. We found that individual dispersal tendencies were influenced by the population's mean boldness and sociability score. For example, individuals from populations with more asocial individuals or with more bold individuals are more likely to disperse regardless of their own personality type. We suggest that identifying behavioural traits facilitating invasions, even at the group level, can thus have direct applications in pest management.
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| 3. |
- Cote, Julien, et al.
(author)
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Personality traits and dispersal tendency in the invasive mosquitofish (Gambusia affinis)
- 2010
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In: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 277:1687, s. 1571-1579
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Journal article (peer-reviewed)abstract
- Ecological invasions, where non-native species spread to new areas, grow to high densities and have large, negative impacts on ecological communities, are a major worldwide problem. Recent studies suggest that one of the key mechanisms influencing invasion dynamics is personality-dependent dispersal: the tendency for dispersers to have a different personality type than the average from a source population. We examined this possibility in the invasive mosquitofish (Gambusia affinis). We measured individual tendencies to disperse in experimental streams and several personality traits: sociability, boldness, activity and exploration tendency before and three weeks after dispersal. We found that mosquitofish display consistent behavioural tendencies over time, and significant positive correlations between all personality traits. Most notably, sociability was an important indicator of dispersal distance, with more asocial individuals dispersing further, suggesting personality-biased dispersal on an invasion front. These results could have important ecological implications, as invasion by a biased subset of individuals is likely to have different ecological impacts than invasion by a random group of colonists.
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| 4. |
- Ferrari, Maud C. O., et al.
(author)
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Effects of turbidity and an invasive waterweed on predation by introduced largemouth bass
- 2014
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In: Environmental Biology of Fishes. - : Springer Science and Business Media LLC. - 0378-1909 .- 1573-5133. ; 97:1, s. 79-90
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Journal article (peer-reviewed)abstract
- Anthropogenic activities lead to changes in characteristics of aquatic ecosystems, including alteration of turbidity and addition of invasive species. In this study, we tested how changes in turbidity and the recent invasion of an aquatic macrophyte, Egeria densa, may have changed the predation pressure by introduced largemouth bass on juvenile striped bass and delta smelt, two species that have seen a drastic decline in recent decades in the Sacramento-San Joaquin Delta. In a series of mesocosm experiments, we showed that increases in vegetation density decreased the predation success of largemouth bass. When placed in an environment with both open water and vegetated areas, and given a choice to forage on prey associated with either of these habitats, largemouth bass preyed mainly on open water species as opposed to vegetation-associated species, such as juvenile largemouth bass, bluegill or red swamp crayfish. Finally, we showed that turbidity served as cover to open water species and increased the survival of delta smelt, an endemic species at risk. We also found that such open water prey tend not to seek refuge in the vegetation cover, even in the presence of an imminent predation threat. These results provide the beginning of a mechanistic framework to explain how decreases in turbidity and increases in vegetation cover correlate with a decline of open water species in the Sacramento-San Joaquin Delta.
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| 5. |
- Hammond, John I., et al.
(author)
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Spatial scale influences the outcome of the predator-prey space race between tadpoles and predatory dragonflies
- 2012
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In: Functional Ecology. - : British Ecological Society. - 0269-8463 .- 1365-2435. ; 26:2, s. 522-531
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Journal article (peer-reviewed)abstract
- 1. How predators and prey distribute themselves across space can have large population and community-level consequences by affecting the frequency and potential strength of interactions between and within trophic levels. The general pattern that emerges from numerous studies is that predators seek areas with higher prey densities and prey avoid areas with higher predation risk. However, little is known about the behavioural mechanisms underlying the emergent spatial patterns between freely interacting predators and prey. 2. We examined the behaviour and space use of groups of Pseudacris regilla (Pacific treefrog) tadpole prey and larval Rhionaeschna multicolor (blue-eyed darner) odonate predators in arenas consisting of four patches of the prey's resources divided into two spatial scales over two observation periods a day apart. Distributions were assayed both alone and together. We predicted scale should inherently affect the resulting spatial patterns because factors such as selection, competition, interference, movement ability and prey responses to predators all have potentially similar effects as scale become larger or smaller. These factors predict that prey should be more able to dictate the spatial pattern at smaller scales and predators at larger scales. 3. Results generally match these predictions with measures of joint space being consistent with the predators dictating the joint space use more than expected at the larger scale. Moreover, at the smaller scale, either the predator and prey responses offset or reverse to favour the prey. We used a model selection approach to look at the underlying behavioural rules shaping these spatial patterns. Prey were more likely to leave patches with lower resources across both scales. However, their response to predators and competitors differed between the scales, with prey appearing to become trapped with predators only at the larger scale and only avoiding other prey at the small scale. 4. These results highlight the importance of investigating freely interacting predators and prey and the factors that are likely to affect the predator's or prey's ability to dictate spatial patterns. An ability to predict predator-prey spatial outcomes should be a great benefit with habitat fragmentation and shifting population densities, distributions and community compositions.
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