1) Consistent individual differences in behaviour (i.e. personality) can be explained in an evolutionary context if they are favoured by life-history trade-offs as conceptualized in the pace-of-life syndrome (POLS) hypothesis. Theory predicts that faster growing individuals suffer higher mortality and that this trade-off is mediated through exploration/risk-taking personality, but empirical support for this remains limited and ambiguous. Equivocal support to the POLS hypothesis suggests that the link between life-history and personality may only emerge under certain circumstances. Understanding personality driven trade-offs would be facilitated by long-term studies in wild populations experiencing different ecological conditions.

2) Here, we tested whether personality measured in semi-captivity was associated with a growth-mortality trade-off via risk-taking in the wild in two sub-populations of juvenile lemon sharks (Negaprion brevirostris) known to differ in their predator abundance. We expected stronger personality driven trade-offs in the predator-rich environment as compared to the predator-poor environment.

3) Sharks were captured yearly from 1995 onwards allowing us to obtain long-term data on growth and apparent survival in each sub-population. We then used a novel open-field assay to test sharks for exploration personality yearly from 2012 to 2017. A subset of the tested sharks was monitored in the field using telemetry to document risk-taking behaviours. We tested (i) if fast explorers in captivity took more risks and grew faster in the wild and (ii) if natural selection acted against more explorative, faster growing sharks.

4) In the sub-population with fewer predators, more explorative sharks in captivity took more risks in the wild and grew faster. In turn, larger, fast-growing sharks had lower apparent survival. In the predator-rich sub-population, despite finding selection on fast growth, we found no link between exploration personality and the growth-mortality trade-off.

5) Our study demonstrates that the association between personality and life-history is favoured in some ecological contexts but not in others. We identify predator and resource abundance as two main potential drivers of the personality mediated trade-off and emphasize that future work on the POLS hypothesis would benefit from an approach integrating behaviour and life-history across ecological conditions.

Dataset: JAE-supp-markrecapture

 

PIT.Tag: Unique individual identifyer

Year: year of capture

Sub.pop: Sub-population of capture (Either "Bimini - NS" (North Sound) or "Bimini - SL" (Sharkland))

std.PCL: Pre-caudal lenght, mean centered with a standard deviation of one within sub-population and year

Growth: yearly growth in cm

std.Growth: Growth, mean centered with a standard deviation of one within sub-population and year

Explo: exploration score in a captive novel-open field test

std.Explo: Exploration score, mean centered with a standard deviation of one within sub-population and year

Survival.y1: survival to year n+1 or more

std.Survival.y1: survival to year n+1 or more, mean centered with a standard deviation of one within sub-population and year

Survival.y2: survival to year n+2 or more

std.Survival.y2: survival to year n+2 or more, mean centered with a standard deviation of one within sub-population and year

 

Dataset: JAE-supp-distancedata

PIT.Tag: Unique individual identifyer

Tracking.season: year of acoustic tagging

Sub.pop: Sub-population of capture (Either "Bimini - NS" (North Sound) or "Bimini - SL" (Sharkland))

std.Explo: Exploration score, mean centered with a standard deviation of one within sub-population and year

Growth: yearly growth in cm

std.Growth: Growth, mean centered with a standard deviation of one within sub-population and year

Survival.y1: survival to year n+1 or more

std.Survival.y1: survival to year n+1 or more, mean centered with a standard deviation of one within sub-population and year

Distance: Distance from the nearest shore (m)

sqrt.Distance: Distance from the nearest shore, square root transformed

 

Dataset: JAE-supp-distancesummary

A summary of "JAE-supp-distancedata" with one line per individual

n: number of tracked observations

Distance: mean distance for the individual

sqrt.Distance: mean distance for the individual, square root transformed

Distancese: standard error of the distance for the individual