Personality traits and dispersal tendency in the invasive mosquitofish (Gambusia affinis)

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.

Exploratory behaviour and stressor hyper-responsiveness facilitate range expansion of an introduced songbird

“…Thus, the release of GCs in response to stressors is also apt to be stronger at range edges. Although data indicate that introduced populations are more exploratory than native ones [7,19,20] and GCs may play a role in population viability after an introduction [22], it remains untested whether increased exploration and altered stress hormone regulation facilitate range expansions.…”

“…However, when familiar resources are available, exploration might have a reduced benefit and be lost through genetic drift [17]; further, in these areas, exploration might increase the likelihood of exposure to toxins and predators, waste time that could be devoted to other activities [18], and increase the likelihood of being out-competed by individuals procuring known resources. Indeed, exploration tends to be stronger in invasive species and invading populations [7,19,20] compared with native species and populations.…”

“…boldness, aggression, response to novelty) may be especially important in novel environments [5][6][7][8][9][10][11][12][13][14][15]. Different selection pressures along a range expansion could select for different levels of these traits between the site of introduction and the edge of the range.…”

When the going gets tough: behavioural type-dependent space use in the sleepy lizard changes as the season dries

“…Within-species differences in space use can generate spatial and temporal variability in interactions within and among species that can, in turn, have major impacts on population and community dynamics. For example, the fact that some individuals move more widely than others or have different habitat preferences than others can have major impacts on disease spread or ecological invasions [19][20][21]. Our fundamental hypothesis is that individual differences in BT within a population can help to explain individual differences in space use.…”

Ecological effects of pharmaceuticals in aquatic systems—impacts through behavioural alterations

“…The ability of potential prey to correctly assess predation risk is therefore crucial for fitness. Dispersal and migration are also examples of behaviours that have direct importance for population persistence, especially in the face of rapid environmental change [11], as individuals that express more active, bold and/or asocial behaviours tend to be more prone to disperse or migrate [12][13][14][15]. Lastly, among fish, schooling-a behaviour tightly linked to sociality-is directly important [16], as it confuses the predator and thereby increases each schooling individual's chance of survival [17].…”