Journal of Animal Ecology

This ‘In Focus’ article examines the study by Chiba et al., highlighting the importance of considering potentially maladaptive plastic responses of harvested animals in selective fishing environments in efforts to conserve wild animal resources.

Animal migration has relevance to fundamental and many applied ecological questions. Theoretical methods can importantly contribute to their answers and therefore, we characterise the existing mechanistic modelling approaches, their structure and assumptions and review their use across taxa and research themes.

The roles of parasites in ecosystems are frequently overlooked, despite the fact that parasitism is the most common animal lifestyle. Here, the authors integrate trematode parasites into measurements of animal biomass in pond ecosystems and find that parasites make large direct energetic contributions, rivalling that of the most abundant free-living groups.

This paper provides a description and analysis of long term patterns of pneumonia in bighorn sheep that have previously been unreported, anecdotal, or described with limited data. Importantly, this analysis reveals some of the underlying biological processes driving the disease.

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A central goal of population and evolutionary biology is to develop a mechanistic understanding of how environmental variation affects individual fitness and population and evolutionary dynamics in natural populations. This study makes an important contribution in this context in indicating the importance of developmental plasticity in individual development and how this may interact with population dynamics.

This study uses microsatellite variation to identify parent-offspring pairs in a population of harvester ant colonies. It is the first measure of a life table and of colony lifetime reproductive success in a population of social insect colonies, opening the way for future studies of the relation between phenotypic variation and reproductive success.

The authors use a novel framework to describe the significant changes to the structure of bird communities resulting from climate change and identify the individual species driving the community changes. This paper is the first to combine a community and species approach to this problem.

The authors measure, for the first time, the whole range of real seed dispersal distances generated by two widespread carnivores that play an essential role in many ecosystems as frugivores and seed dispersers. This study provides the first empirical evidence of functional diversity among seed dispersal kernels generated by carnivorous mammals.

Animal space use is fundamental to understanding several ecological processes, but this field is split into separate areas without much productive contact. The aim here is to achieve one such bridge by comparing GPS-data from red deer with theoretical movement models with known underlying behavioural mechanisms and statistical properties.

Classical methods for measuring the rate of populatoin spatial spread are designed for species dispersing over one or two dimensional space. In this paper, a novel methodology is suggested for measuring the rate of spread in river networks, based on representing a river network by means of a weighted graph.

Here it is shown that non-consumptive interactions in the diverse predator guilds of physically benign habitats reduce predation rates, resulting in an unexpected increase in top-down control with increasing disturbance. Therefore, considering changes in food-web complexity, especially the non-consumptive effects of top predators, is essential to understand species interactions across environmental gradients.

This study unambiguously demonstrates that genetic restoration reversed the declining trend of a small, inbred population of the endangered Florida panther. Further, the authors show that the panther population would have continued to decline and faced a substantial risk of extinction if genetic restoration initiative had not been implemented.

This paper reports the first empirical demonstration of a positive effect of propagule pressure in interaction with genetic background on population persistence in a laboratory system. This paper also reports for the first time intrinsic differences in demographic variance between geographic strains of the same species.

This paper provide the first concrete evidence of adult sex ratio adjustment by a pandalid shrimp, a group that has been treated as a model in the sex allocation theory, in response to selective fishing. This sex ratio plasticity in response to selective harvesting may have negative consequences for conservation.

Using intra-species variation in three-spined sticklebacks, the authors show that dwarfism evolves rapidly in resource poor lakes in the absence of smaller competitors. This is one of the first studies to examine in detail the ecological correlates of dwarfism within a species, and the first to do so in fish.

Maintenance of colour polymorphism is particularly problematic in aposematic species, because selection should favour monomorphic warning coloration. Here the authors show that aposematic wood tiger moth expresses differential morph-linked immune responses in high densities. This can favour morphs in their respective natural environment, and facilitate maintenance of colour polymorphism.

Some species use phenotypic plasticity (rather than genetic adaptation) to survive shifting environments. (i) This is the first study to examine the relative fitness of a ‘plastic’ species. (ii) Even knowing this species is ‘plastic,’ we found a shockingly wide range of temperatures at which this species performs optimally.

Provisioning of food to wild birds is widespread but its ecological impacts are poorly understood. The authors show that winter provisioning with fat results in smaller relative yolk mass and reduced yolk carotenoid concentrations in early breeders, while these effects are not seen in birds provisioned with fat-plus-vitamin E. The results highlight how the ecological impacts of provisioning can depend on the nutritional profile of foods.

The authors use a long-term study of sea duck breeding ecology to show that a precipitous increase in the abundance of an alternative prey species, driven by human land-use change in mid-continent North America, has had dramatic impacts on the breeding success of a sub-Arctic seabird through effects on shared predators.

Using biologging methodology (GPSTDR data) and stable isotope analysis, this study addresses foraging niche competition of juvenile animals with similar-sized adults of a sympatric species. Such ecological interactions have received little attention, yet juvenile foraging success and survival are key factors influencing population dynamics.

The manner in which animals respond to risk is crucial in understanding species coexistence. Here the authors show that avoidance of more dominant predators by cheetahs in northern Botswana is reactive rather than predictive – a strategy that could be key in enabling competing species to coexist in an ecosystem where risks are widespread and recurrent.