The understanding of feeding habits is important for anurans in general, both from an ecological and a phylogenetic perspective. For diurnal poison frogs belonging to the Dendrobatidae family, diet aspects play a crucial role in their defense and survival. Herein, we investigated feeding habits, foraging behaviour, and overall effects of habitat, sex, and body size on the diet of individuals of...

The impact of seawater acidification on calcifying organisms varies at the species level. If the impact differs between predator and prey in strength and/or sign, trophic interactions may be altered. In the present study, we investigated the impact of 3 different seawater pCO2 levels (650, 1250 and 3500 μatm) on the acid–base status or the growth of 2 predatory species, the common sea star Aste...

Accurate estimates of penguin energetics would represent an important contribution to our understanding of the trophodynamics of the Southern Ocean ecosystem and our ability to predict effects of environmental change on these species. We used the heart rate-rate of oxygen consumption technique to estimate rate of energy expenditure in adult king penguins raising a chick, in combination with dat...

Many demersal fish species rely on benthic prey as food sources for part of, or in some cases, all of their life history. We investigated the relationships between prey and predator abundance and prey size and predator mouth gape size for nine demersal fish species. Of the species analysed, four showed a significant positive increase in abundance with increasing prey abundance. Prey size is tho...

We evaluate the current commercial harvest of harp seal (Pagophilus groenlandicus) and proposed subsistence harvests of northern fur seal (Callorhinus ursinus) pups based on intraspecific comparisons. These comparisons utilize a pattern derived from 167 cases of estimated consumption rates by large mammals. In all cases, the predation rates involve large mammal prey less than 1 year of age. Rec...

The chemical composition, metabolism, and feeding ecology of the cydippid ctenophore Callianira antarctica (Chun 1897) were investigated during autumn and winter 2001 and 2002 in the vicinity of Marguerite Bay, an embayment on the western Antarctic Peninsula shelf. C. antarctica had relatively high carbon (C) and nitrogen (N) values (average: 8.4% C and 1.8 % N [% dry weight, DW]), further sugg...

Understanding the benefits and costs of acquiring and consuming different forms of animal matter by primates is critical for identifying the selective pressures responsible for increased meat consumption in the hominin lineage. Chimpanzees (Pan troglodytes) are unusual among primates in the amount of vertebrate prey they consume. Still, surprisingly little is known about the nutritional benefit...

Large carnivores inhabiting ecosystems with heterogeneously distributed environmental resources with strong seasonal variations frequently employ opportunistic foraging strategies, often typified by seasonal switches in diet. In semi-arid ecosystems, herbivore distribution is generally more homogeneous in the wet season, when surface water is abundant, than in the dry season when only permanent...

Intra-guild predation (IGP) – where a top predator (IGPred) consumes both a basal resource and a competitor for that resource (IGPrey) – has become a fundamental part of understanding species interactions and community dynamics. IGP communities composed of intraguild predators and prey have been well studied; however, we know less about IGP communities composed of predators, pathogens, and reso...

Some prey are exceptionally difficult to digest, and yet even non-specialized animals may consume them—why? Durophagy, the consumption of hard-shelled prey, is thought require special adaptations for crushing or digesting hard shells avoid many potential costs this type. But lacking specializations nevertheless include hard-bodied in their diets. We describe several non-mutually exclusive adapt...