Behavioural Syndromes and Links to Extinction Risk and Population Viability Under Changing Land Use

Abstract

The rapid change in land use driven by agricultural intensification, urbanization, and habitat
fragmentation is an increasingly significant threat to biodiversity. Still, not all species respond to these
environmental pressures in the same way. This paper analyses behavioural syndromes, which refer to
stable associations between traits, including boldness, activity, and dispersal, and extinction risk and
the viability of a population in changed landscapes. The behavioural and demographic data from 18
terrestrial vertebrate species were collected across 6 divergent land-use regimes, comprising 420
standardised behavioural trials and 35 long-term population datasets. Stochastic population viability
models were fitted with behavioural traits to assess the survival, fecundity, dispersal, and extinction
history of populations under progressive land-use scenarios. The finding indicates that high-risk
behavioural syndrome populations had 0.42 units of survival per generation of adults and 1.6
disturbance encounters per time step of mortality events. Risk-averse syndromes, on the other hand,
had reduced dispersal, leading to a 1.9-fold reduction in successful colonization events within
fragmented habitat networks. Behaviour-informed models used behaviour information to predict
extinction risk 21 log-units better than behaviour-neutral models. The influence of population growth
on the viability results was reduced by 0.31 units in the high-land-use-intensity landscapes, with
behavioural effects explaining 38 units of variance. These results show that behavioural syndromes
are significant mediators of species' effects on land-use change, with individual behavioural
consistency linked to population-level persistence. Assessment of conservation incorporating
behavioural aspects will be a better predictor of extinction risk and of successful land-use management
in the face of rapid environmental change.