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Increased attraction to humans and their objects often arises after repeated and positive human-wildlife encounters (e.g. food provided in tourist settings). The causes of this 'over-attraction', which may result from a learned association between humans and food, are still poorly studied in wild animals. Understanding the influence of humans on animals' responses is yet crucial to prevent negative effects (e.g. aggression). We presented three novel objects to two groups of free-ranging brown skuas ( Catharacta antarctica ssp. lonnbergi ) in the remote sub-Antarctic, where their habitats show no or minimal human disturbance. Skuas in one group (Verte) had previously participated in repeated food-rewarded behavioural and cognitive tasks with a human experimenter; skuas in the other group (Ratmanoff) had never done so. Objects consisted of (i) one natural-food-resembling object (plastic fish), (ii) one anthropogenic food object (real cake slice), and (iii) one anthropogenic non-food object (yellow glove). Verte group skuas approached the human experimenter and pecked significantly more and sooner at novel objects. Human-food association may have thus resulted in increased attraction to humans and novelty exploration in previously naive brown skuas, making this species a useful model for investigating the consequences of experience with humans on wildlife behaviour.

Islands have always provided ideal natural laboratories for assessing ecological parameters influencing behaviour. One hypothesis that lends itself well to testing in island habitats suggests that animals frequenting highly variable environments should be motivated to approach and interact with (i.e. explore) novelty. Intra-species comparisons of populations living in ecologically different island habitats may, thus, help reveal the factors that modulate animals' responses to novelty. In this study, we presented novel objects to two geographically isolated breeding populations of the black-faced sheathbill (Chionis minor), a sedentary land-based bird that frequents remote sub-Antarctic islands. In the first population (Chionis minor ssp. crozettensis), the "Crozet group" (Baie du Marin, Ile de la Possession, Crozet Islands), breeding pairs inhabit a variable habitat close to penguin (Aptenodytes patagonicus) colonies. In the second population (Chionis minor ssp. minor), the "Kerguelen group" (île Verte, Morbihan gulf, Kerguelen Islands) breeding pairs live in penguin-free territories. In this latter population, the environment is less variable due to the presence of a broad intertidal zone which ensures year-round food availability. At both Kerguelen and Crozet, at least one breeding partner in all pairs approached at least one of the novel objects, and we found no significant differences in the latency of approach between the two populations. However, sheathbills at Crozet touched objects significantly more than birds at Kerguelen, and were also faster to touch them. We discuss how environmental variability, along with other potential influencing factors, may favour exploration of novelty in this wild insular bird., (© 2024. The Author(s).)

Many animals respond to and use social cues emitted by other species (e.g., head direction). In the context of human-animal communication, these capacities have been attributed to regular and longstanding exposure to humans. We presented wild brown skuas (Catharacta antarctica ssp. lonnbergi) with two versions of an object-choice paradigm. In the cooperative version (Experiment 1), one human experimenter provided a simple and salient cue indicating which of two containers covered a food reward. The cues administered consisted of touching, looking at, pointing at, or pointing and looking at the container hiding food. In Experiment 1, skuas could thus cooperate with an experimenter by using the cues provided to locate the rewarded container. In the competitive version (Experiment 2), two human experimenters presented a platform with a visible food reward. In six experimental conditions, we varied experimenters' body orientation, head orientation, eye-gaze direction, face occlusion, and mouth occlusion, as well as the platform's location, ensuring that in each case only one experimenter had visual access to the rewarded platform. Here, birds could compete with the experimenters by robbing the human who does not see the food. Skuas failed to use human-given cues spontaneously in Experiment 1, and took the reward regardless of whether the experimenters could see in Experiment 2. Our results contrast with those obtained on other wild birds with pre-experience with humans. Hopefully, our findings will stimulate further research in order to illuminate the potential role of such experience in the capacity to respond to and use human-given cues. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

A wide range of animal species accumulate objects in, on, and/or around structures they build. Sometimes, these accumulations serve specific functions (e.g. structural or isolating features) or are purely incidental, while in other cases the materials are deliberately displayed to serve signalling purposes (extended phenotype signals). In this pilot study, we employed systematic in situ observations and camera trapping to describe for the first time that both partners of a territorial shorebird, the black-faced sheathbill (Chionis minor ssp minor) collect, carry, and arrange colourful marine shells and dry twigs within and around their nest cavity. Our observations expand the taxonomic breadth of avian extended phenotype signals, by showing that at least one species within a largely understudied group i.e., Charadriiformes, exhibits nest-decoration behaviour. Multiple manipulative experiments are needed to explore further the signalling function of these decorations, which opens new exciting avenues for animal communication and cognition research., (Copyright © 2021 Elsevier B.V. All rights reserved.)