Uncertainty in experts’ judgments exposes the vulnerability of research reporting anecdotes on animals’ cognitive abilities

Expertise in science, particularly in animal behaviour, may provide people with the capacity to provide better judgments in contrast to lay people. Here we explore whether experts provide a more objective, accurate and coherent evaluation of a recently reported anecdote on Atlantic puffin (Fratercula arctica) “tool use” (recorded on video) which was published in a major scientific journal but was received with some scepticism. We relied on citizen science and developed a questionnaire to measure whether experts in ethology and ornithology and lay people agree or disagree on (1) the description of the actions that they observe (the bird takes a stick in its beak), (2) the possible goal of the action (nest-building or grooming) and (3) the intentional component of the action (the bird took the stick into its beak in order to scratch itself). We hypothesised that contrary to the lay people, experts are more critical evaluators that is they are more inclined to report alternative actions, like nest building, or are less likely to attributing goal-directedness to the action in the absence of evidence. In contrast, lay people may be more prone to anthropomorphise utilising a teleological and intentional stance. Alternatively, all three groups of subjects may rely on anthropomorphism at similar levels and prior expertise does not play a significant role. We found that no major differences among the evaluators. At the group levels, respondents were relatively uncertain with regard to the action of the bird seen on the video but they showed some individual consistency with regard to the description of the action. Thus, we conclude that paradoxically, with regard to the task our experts are typically not experts in the strict sense of the definition, and suggest that anecdotal reports should not be used to argue about mental processes.

Migratory movements of Atlantic puffins Fratercula arctica naumanni from high Arctic Greenland

Although the Atlantic puffin Fratercula arctica is well studied throughout its temperate and low Arctic breeding range, few have studied the species in its far northern distribution. This study is the first to present data on the migratory movements of the “large-billed” subspecies, F. a. naumanni, that breeds in the high Arctic and which has significantly larger body size than those farther south. During 2013–2015, migration tracks were collected from nine adult puffins (6 males and 3 females) tagged with geolocators in northwest Greenland. Overall, female puffins traveled farther than males on their annual migration, with one female puffin traveling over 13,600 km, which was nearly a third farther than any tagged male in our study. Differential migration was observed in migratory phenology and route, with males using a form of chain migration with acute synchrony between individuals while females appeared to largely use leap-frog migration and showed little synchrony between individuals. Extreme sexual segregation in wintering areas was evidenced by two females that migrated to the southern limit of the species’ range while the six males remained at the northern limit, and wintered along the sea ice edge during portions of the non-breeding season. Male puffins thus wintered in regions with sea surface temperatures up to 10° C cooler than female puffins, and in areas with generally colder sea surface temperatures when compared to previously known wintering areas of temperate and low Arctic puffin breeding populations. The degree to which body size enables male F. a. naumanni to remain in colder waters likely reflects differing life history constraints between sexes and populations (i.e., subspecies). Further study is warranted to investigate how recent changes in climate have further exacerbated the observed differences between sexes in high Arctic puffins and possibly other marine avian species.

Long-term stability in the volume of Atlantic Puffin (Fratercula arctica) eggs in the western North Atlantic

In the eastern North Atlantic, declines in the volume of Atlantic Puffin (Fratercula arctica Linnaeus, 1758) eggs have been associated with shifts in the marine ecosystem, such as changes in the abundance of forage fishes and increasing sea-surface temperatures. In the western North Atlantic, where similar shifts in oceanographic conditions and changes in the abundance of forage fishes have presumably occurred, trends in the volume of Atlantic Puffin eggs remain unknown. In this study, we investigate Atlantic Puffin egg volume in the western North Atlantic. We compiled 140 years (1877–2016) of egg volume measurements (n = 1,805) and used general additive mixed-effects models to investigate temporal trends and regional variation. Our findings indicate that Atlantic Puffin egg volume differs regionally but has remained unchanged temporally in the western North Atlantic since at least the 1980s.

Size variation in mid-Holocene North Atlantic Puffins indicates a dynamic response to climate change

Seabirds are one of the most at-risk groups, with many species in decline. In Scandinavia, seabirds are at a heightened risk of extinction due to accelerated global warming. Norway is home to significant portion of the European Atlantic Puffin (Fratercula arctica) populations, but Norwegian populations have declined significantly during the last decades. In this paper we use biometric data from modern and archaeological F. arctica specimens to investigate patterns in body size variation over time of this iconic species. We aimed to set out a baseline for our archaeological comparison by firstly investigating whether modern subspecies of F. arctica are reflected in the osteological characters and are enough to distinguish subspecies from the bones alone. We then investigated if archaeological remains of F. arctica differ in size from the modern subspecies. Our results show that the subspecies Fratercula arctica naumanni was distinctly larger than the other subspecies. However, Fratercula arctica arctica and Fratercula arctica grabae were difficult to separate based on size. This generally supports ornithological observations. Post-Medieval F. arctica bones from Måsøy were similar to modern F. a. arctica populations. The mid-Holocene remains from Dollsteinhola overlaps with the modern size ranges of F. a. arctica and F. a. grabae but are generally shorter and more robust. Dollsteinhola is located close to the borders of the modern breeding ranges of both F. a. arctica and F. a. grabae. We consider it therefore likely that given the mid-Holocene climatic oscillations, breeding ranges of the two subspecies shifted north or south accordingly. However, this does not explain the different proportions of the Dollsteinhola specimens. Our data provide the first evidence for shifting distributions in ancient Atlantic Puffins and represent the first osteological analysis of Fratercula arctica subspecies.

Contrasting phenological and demographic responses of Atlantic Puffin (Fratercula arctica) and Razorbill (Alca torda) to climate change in the Gulf of Maine

The Gulf of Maine is warming faster than most of the world’s ocean and is also the southern-most limit for nesting, cold-adapted Atlantic Puffin (Fratercula arctica) and Razorbill (Alca torda). Beginning in 1995, the Atlantic Laboratory for Avian Research has collected annual data on phenology, productivity, and fledgling body condition for puffins and Razorbills nesting at Machias Seal Island. Here, we aimed to quantify changes in these measures of breeding performance and assess whether they are related to environmental conditions. As predicted, we found that all measures of breeding performance (except puffin fledge date) have changed between 1995 and 2020, and in many cases, puffins and Razorbills are responding differently. Specifically, hatch date has retreated for puffins (occurring approximately 1 week later in 2011–2020 than in 1995–2004) and advanced for Razorbills (occurring approximately 1 week earlier in 2011–2020 than in 1995–2004). We found that environmental conditions were important predictors for measures of breeding performance, but importance of environmental conditions differ both between the species and among the measures of breeding performance. As the climate continues to warm, we expect continued changes in breeding performance of puffins and Razorbills. Further research is needed to understand the reasons for differences between the 2 species and the impacts of continued warming.