The research, conducted by M. Candelaria Biagiotti Barchiesi, Germán O. García, Melina V. Castano, and Laura M. Biondi of the Instituto de Investigaciones Marinas y Costeras at the Universidad Nacional de Mar del Plata and CONICET, focused on a species that has become a textbook example of ecological flexibility. Kelp Gulls are generalist foragers with a remarkably diverse repertoire of feeding tactics, from probing intertidal mudflats to scavenging at waste facilities and even preying on other seabirds. Because these birds frequently feed on anthropogenic food resources, the team hypothesized that social learning might play a central role in how individuals discover and master new ways of exploiting them. To test this idea rigorously, they designed a controlled experiment in which naïve gulls, birds with no prior experience of the task, were given the opportunity to watch a demonstrator solve a problem before attempting it themselves.

The experimental apparatus was an opaque box containing food, a classic extractive foraging task that requires the animal to discover that a specific action, in this case manipulating the lid, releases the reward. Because the box was opaque, success could not be achieved by simply seeing the food; the birds had to learn the technique itself. The study involved twenty-five naïve observer gulls, thirteen adults and twelve immatures, along with six control individuals that received no demonstration. In a baseline phase conducted before any demonstration took place, only twenty-eight percent of the future observers and thirty-three percent of the controls managed to solve the box on their own, confirming that the task was genuinely difficult for an uninstructed gull. This low baseline success rate set the stage for a clean test of whether social information could change the odds.

The results were striking. During the test phase, after observers had watched a demonstrator open the box, not a single control bird solved the task, while fifty-two percent of the observers succeeded. In other words, watching a companion roughly doubled the probability of success compared with the observers’ own baseline performance, and it made the difference between total failure and moderate success relative to uninformed birds. The effect, however, was not uniform across all ages. Only adult observers were significantly more successful and significantly faster at both contacting the box and solving it, both compared with the control group and compared with their own pre-demonstration attempts. This age-specific pattern suggests that adult gulls may be better positioned to translate observed information into effective action, perhaps because of greater motor competence, stronger motivation, or more refined attention to the demonstrator’s behavior.

Intriguingly, the study found no differences in overall performance between age classes either before or after the demonstration, indicating that immatures were not inherently worse at the task once they had the same social information. Nor did the age of the demonstrator matter: observers learned equally well whether they watched an adult or an immature bird performing the technique. The demonstrator’s own neophobic response, its hesitancy or boldness around the novel box, also failed to predict whether observers succeeded. These null results are informative in themselves. They suggest that the critical ingredient in social transmission here was the demonstrator’s technique rather than its social status or emotional demeanor, and that gulls of any age can serve as effective sources of social information within a flock.

One of the most technically interesting aspects of the study was its use of a two-action design, in which different demonstrators could be shown using different lid-opening techniques. This allowed the researchers to ask not merely whether observers learned, but what they learned. The answer was clear: observers predominantly adopted the specific technique used by their demonstrator, and immatures showed greater consistency than adults in copying the exact lid type they had seen opened. This fidelity to the demonstrated method is a hallmark of true social learning rather than mere local enhancement, the simpler process in which an animal is merely attracted to a location or object by another’s presence. By matching the demonstrator’s action, the gulls demonstrated that they had extracted procedural information from observation, effectively copying a foraging behavior they had never performed themselves.

The implications of these findings extend well beyond the aviary. Landfills and other urban food subsidies bring large numbers of gulls into close and repeated contact, creating ideal conditions for social transmission of novel foraging innovations. If one inventive individual discovers a new way to access food, whether opening a container, exploiting a new waste stream, or targeting a novel prey, social learning provides a fast track for that innovation to spread through the population. This dynamic helps explain how generalist species like the Kelp Gull can rapidly adjust their behavior to changing environmental conditions, a capacity that is increasingly valuable as urbanization transforms coastal ecosystems across the Southern Hemisphere and beyond. It also raises practical considerations for wildlife management, since behaviors learned socially can be difficult to reverse once established in a local population.

The study also contributes to a broader scientific conversation about cognition in seabirds, a group historically understudied relative to primates, corvids, and parrots. Gulls belong to the charadriiform birds, and accumulating evidence now points to sophisticated cognitive abilities within this lineage, including problem-solving, behavioral flexibility, and social responsiveness. The present experiment adds a controlled, quantitative demonstration that Kelp Gulls possess the capacity for observational learning of an extractive foraging task, placing them firmly within the growing roster of species whose ecological success is underpinned by social cognition. The combination of diverse foraging tactics, cognitive ability, and social transmission appears to be a potent recipe for thriving in human-dominated landscapes.

Methodologically, the work reflects careful attention to animal welfare and experimental design. The gulls were captured with adherence to Argentine legal requirements and guidelines for the use of animals in research, with the experimental protocol approved by the National University of Mar del Plata Animal Ethics Committee. All birds were housed with veterinary assistance during their stay in the aviary and were released at their original habitats once testing was complete. The research was funded by Argentina’s Agencia Nacional de Promoción de la Investigación, el Desarrollo Tecnológico y la Innovación, and the authors acknowledge the cooperation of workers at the Mar del Plata Landfill, whose daily reality alongside these birds provided the inspiration for the study.

As cities continue to expand and wildlife increasingly shares space with people, understanding the mechanisms of behavioral adaptation becomes ever more urgent. This study of urban Kelp Gulls offers a vivid reminder that the animals flourishing around us are not merely lucky scavengers but capable learners, watching one another, copying successful techniques, and building shared behavioral traditions that ripple through their flocks. In the gull rifling through a landfill, scientists are glimpsing the cognitive machinery that allows some species to turn humanity’s footprint into opportunity, one observed behavior at a time.

Subject of Research: Social learning of a novel foraging task in immature and adult urban Kelp Gulls

Article Title: Social learning of a foraging task in immature and adult urban Kelp Gulls (Larus dominicanus)

Article References: Biagiotti Barchiesi, M. C., García, G. O., Castano, M. V., & Biondi, L. M. (2026). Social learning of a foraging task in immature and adult urban Kelp Gulls (Larus dominicanus). Animal Cognition. https://doi.org/10.1007/s10071-026-02102-z

Image Credits: AI Generated

DOI: 10.1007/s10071-026-02102-z

Keywords: Kelp Gull, social learning, animal cognition, urban wildlife, foraging behavior, seabirds, behavioral flexibility, urbanization, two-action task, social information, extractive foraging, Larus dominicanus