Environmental heterogeneity decreases reproductive success via effects on foraging behaviour

Abstract

Environmental heterogeneity shapes the uneven distribution of resources available to foragers, and is ubiquitous in nature. Optimal foraging theory predicts that an animal's ability to exploit resource patches is key to foraging success. However, the potential fitness costs and benefits of foraging in a heterogeneous environment are difficult to measure empirically. Heterogeneity may provide higher-quality foraging opportunities, or alternatively could increase the cost of resource acquisition because of reduced patch density or increased competition. Here, we study the influence of physical environmental heterogeneity on behaviour and reproductive success of black-legged kittiwakes, Rissa tridactyla . From GPS tracking data at 15 colonies throughout their British and Irish range, we found that environments that were physically more heterogeneous were associated with longer trip duration, more time spent foraging while away from the colony, increased overlap of foraging areas between individuals and lower breeding success. These results suggest that there is greater competition between individuals for finite resources in more heterogeneous environments, which comes at a cost to reproduction. Resource hotspots are often considered beneficial, as individuals can learn to exploit them if sufficiently predictable. However, we demonstrate here that such fitness gains can be countered by greater competition in more heterogeneous environments.

Environmental heterogeneity promotes individual specialisation in habitat selection in a widely distributed seabird

“…This pattern was evident across multiple environmental variables, which we also show influence kittiwake habitat selection at the species and population levels, most likely because of their effects on resource distribution and availability. These results are among early evidence of individual specialisations in habitat selection specifically (see also Bonnet-Lebrun et al, 2018;Leclerc et al, 2016), and provide evidence that environmental heterogeneity, a known driver of resource distributions and intraspecific competition (Trevail, Green, Sharples, Polton, Miller, et al, 2019), gives rise to individual specialisations in foraging behaviour.…”

“…On average, kittiwakes preferentially foraged in shallower, well mixed waters where tidal currents can create hotspots of shoaling fish that are the staple of kittiwakes' diet (Zamon, 2003); and avoided deep waters where vertical mixing restricts access to prey at the surface (Carroll et al, 2015) and seasonal depletion in stratified waters reduces foraging opportunities (Behrenfeld & Boss, 2014) and sandeel availability (Jensen et al, 2003). Kittiwakes strongly selected for cooler SST, indicative of local upwelling and productivity (Benazzouz et al, 2014) and typically beneficial to many marine species at seasonal timescales because cold-adapted plankton species are larger and F I G U R E 5 Kittiwake colonies coloured by (a) environmental heterogeneity (Trevail, Green, Sharples, Polton, Miller, et al, 2019) and (b-d) individual repeatability in habitat selection of front strength, front distance and front persistence. There was a significant correlation between environmental heterogeneity and individual repeatability in habitat selection of each three ocean front metrics, presented in Figure 4 and shown spatially here.…”

From pup to predator: generalized hidden Markov models reveal rapid development of movement strategies in a naïve long‐lived vertebrate

“…Such behavioural plasticity might be driven by regional and seasonal differences in the diversity of available foraging habitat or prey types. In this case, the areas used by Scottish pups, encompassing much of the north-western North Sea, represent a more homogeneous environment than the Celtic and Irish Seas off the coast of West Wales (Trevail et al 2019) (Supplementary material Appendix 6 Fig. A5).…”

Production and export of liquefied gas: transformation of business models taking into account global trends in decarbonization and digitalization

“…Между тем, исчерпав стартовые преимущества для развития, компании (корпорации) нефтегазового сектора, реализующие СПГ-проекты, могут утратить темпы роста. В связи с этим следует обратить внимание на возможности цифровизации, претворяя в жизнь которые активно развивается «зеленая» энергетика на Западе (Trevail et al, 2019;Wood et al, 2020).…”