A citizen science trial to assess perception of wild penguin welfare

Wild penguins are facing increased threats to their populations and their welfare as a consequence of human activities. Understanding the perception of animal welfare is essential to identify ethical concerns related to the negative impact of anthropogenic factors on wild species and to guide conservation efforts that reflect societal values. Since penguin conservation is of general interest, we examined the human dimension of welfare assessment across a range of interest groups concerned with penguins, seabird biology and wildlife conservation. We provided participants with a Penguin Welfare Assessment Tool (PWAT) based on the five domains model. The PWAT supports consideration of the impact of four physical aspects on welfare-relevant mental states. Bibliometric analysis of keywords from 347 scientific articles indicated that penguins around the world face five main types (themes) of anthropogenic factors and we then developed five hypothetical scenarios, each related to one theme. Seventy-five participants scored the overall impact of the events described in the scenarios on penguin welfare as negative using the PWAT. Participants rated short-duration, high-intensity events (i.e., being trapped in a ghost fishing net) as having a significantly more severe impact on penguin welfare than low-intensity, long-duration events (P < 0.0001). Scores provided by participants for each domain for each scenario were largely as expected and we found good correlation (all P < 0.0001) between the physical domains and “mental state” for all scenarios, indicating that the tool was facilitating the participants' assessment of welfare. No evidence was found that experience of working or studying penguins, or indeed any other demographic factor investigated, influenced the assessments of welfare. We found little agreement between participants in the scores provided (unalike scores mostly between 0.7 and 0.8), and agreement between participants with experience of working with penguins was no better than between participants without such experience. We discuss the possibility that low agreement within different interest groups may be improved by providing more scientific information to support the evaluation of penguin welfare. We conclude that scientific knowledge of penguin biological responses to anthropogenic factors is vital to support the evaluation of wild penguin welfare by the public and other stakeholders

Evolutionary factors affecting the cross-species utility of newly developed microsatellite markers in seabirds

Microsatellite loci are ideal for testing hypotheses relating to genetic segregation at fine spatio-temporal scales. They are also conserved among closely related species, making them potentially useful for clarifying interspecific relationships between recently diverged taxa. However, mutations at primer binding sites may lead to increased non-amplification, or disruptions that may lead to decreased polymorphism in non-target species. Furthermore, high mutation rates and constraints on allele size may also lead, with evolutionary time, to an increase in convergently evolved allele size classes, biasing measures of interspecific genetic differentiation. Here, we used next-generation sequencing to develop microsatellite markers from a shotgun genome sequence of the sub-Antarctic seabird, the thin-billed prion (Pachyptila belcheri), that we tested for cross-species amplification in other Pachyptila and related sub-Antarctic species. We found that heterozygosity decreased and the proportion of non-amplifying loci increased with phylogenetic distance from the target species. Surprisingly, we found that species trees estimated from interspecific FST provided better approximations of mtDNA relationships among the studied species than those estimated using DC, even though FST was more affected by null alleles. We observed a significantly non-linear second order polynomial relationship between microsatellite and mtDNA distances. We propose that the loss of linearity with increasing mtDNA distance stems from an increasing proportion of homoplastic allele size classes that are identical in state, but not identical by descent. Therefore, despite high cross-species amplification success and high polymorphism among the closely related Pachyptila species, we caution against the use of microsatellites in phylogenetic inference among distantly related taxa

Evidence of age-related improvement in the foraging efficiency of Adelie penguins

Age variation in reproductive performance is well-documented but the mechanisms underlying this variation remain unclear. Foraging efficiency is likely to be a key source of demographic variation as it determines the amount of energy that can be invested in fitness-related activities. Evidence of age related changes in the foraging efficiency of adult seabirds is scarce and inconsistent. We investigated the effects of age on the foraging efficiency of breeding Adelie penguins, a relatively short-lived seabird species, in order to gain a broader perspective on the processes driving variation in ageing rates. We found support for a positive effect of age, either linear or levelling off at old ages, on both our proxies for daily catch rate and catch per unit effort. Across all age classes, males were more performant foragers than females. We found no strong evidence for differing ageing patterns between sexes or individual quality levels, and no evidence for senescence. We infer that continuous individual improvement could be responsible for a larger amount of the variation in foraging efficiency with age at our study site, compared with selective disappearance of underperforming phenotypes. The different results reported by other studies highlight the need to conduct longitudinal studies across a range of species in different environments

Introduced Mammalian Predators Induce Behavioural Changes in Parental Care in an Endemic New Zealand Bird

The introduction of predatory mammals to oceanic islands has led to the extinction of many endemic birds. Although introduced predators should favour changes that reduce predation risk in surviving bird species, the ability of island birds to respond to such novel changes remains unstudied. We tested whether novel predation risk imposed by introduced mammalian predators has altered the parental behaviour of the endemic New Zealand bellbird (Anthornis melanura). We examined parental behaviour of bellbirds at three woodland sites in New Zealand that differed in predation risk: 1) a mainland site with exotic predators present (high predation risk), 2) a mainland site with exotic predators experimentally removed (low risk recently) and, 3) an off-shore island where exotic predators were never introduced (low risk always). We also compared parental behaviour of bellbirds with two closely related Tasmanian honeyeaters (Phylidonyris spp.) that evolved with native nest predators (high risk always). Increased nest predation risk has been postulated to favour reduced parental activity, and we tested whether island bellbirds responded to variation in predation risk. We found that females spent more time on the nest per incubating bout with increased risk of predation, a strategy that minimised activity at the nest during incubation. Parental activity during the nestling period, measured as number of feeding visits/hr, also decreased with increasing nest predation risk across sites, and was lowest among the honeyeaters in Tasmania that evolved with native predators. These results demonstrate that some island birds are able to respond to increased risk of predation by novel predators in ways that appear adaptive. We suggest that conservation efforts may be more effective if they take advantage of the ability of island birds to respond to novel predators, especially when the elimination of exotic predators is not possible

Investigation of causes and effects of predation by herring (Larus argentatus) and great black-backed gulls (L. marinus) on black-legged kittiwakes (Rissa tridactyla) on Gull Island, Newfoundland

In previous studies it has been observed that herring gulls (Larus argentatus) and great black-backed gulls (L. marinus) depredated breeding black-legged kittiwakes (Rissa tridactyla) that nest along the southeastern coast of Newfoundland, Canada. However, the causes and effects of large gull predation on kittiwakes was never extensively investigated nor quantified. In this study, herring gull and great black-backed gull predation on black-legged kittiwakes at Gull Island, southeastern Newfoundland was quantified at four study plots in relation to the timing of the annual spawning arrival of capelin (Mallotus villosus), the size of kittiwake sub-colonies (number of nests), kittiwake nest-site characteristics, and wind conditions. I also investigated the impact of large gull predation on kittiwake breeding performance during 1998 and 1999. -- I compared large gulls' predation attempt frequency among three periods: before mean gull hatching, between mean gull hatching and the arrival of capelin, and following capelin arrival. In both years, the frequency of gull predation attempts on kittiwakes differed significantly among the three periods, with highest levels of predation occurring after gull chicks hatched but before capelin arrival. Overall gull predation attempt levels were lower in 1999, when capelin spawned earlier, than in 1998. -- Nesting density and the location on the cliff were kittiwake nest-site characteristics that affected significantly the risk of predation. Breeding success (number of successful nests) was influenced by nesting density and ledge width. Additionally, I found that both risk of predation and breeding success varied significantly among plots. Individual kittiwake nests at the smallest plot experienced a higher probability of attack by large gulls than nests at larger plots. Hence, the percentage of failed nests was highest at the smallest plot and decreased as the size of the plots increased. Regardless of wind conditions both gull species attacked nest sites located on upper parts to a higher likelihood than sites located on middle and lower parts of the cliffs. However, during calm conditions, roofs over nest sites reduced the risk of predation by herring gulls, whereas sites located on narrow ledges were less likely to be attacked by great black-backed gulls. During windy conditions, nesting density affected which sites were attacked by great black-backed gulls. -- The level of gull predation behaviour was significantly correlated with the percentage of kittiwake eggs and chicks that disappeared within a week. I estimated that 43% of kittiwake eggs and chicks at Gull Island were taken by gulls in 1998 and 30% in 1999. My results demonstrated that kittiwakes have been indirectly (through increased predation by gulls) affected by the delayed arrival and lower abundance of capelin, and that kittiwake nest-site characteristics, and the size of a sub-colony were significantly correlated with the risk of depredation

Fitting Markovian binary trees using global and individual demographic data

We consider a class of continuous-time branching processes called Markovian binary trees (MBTs), in which the individuals lifetime and reproduction epochs are modelled using a transient Markovian arrival process (TMAP). We develop methods for estimating the parameters of the TMAP by using either age-specific averages of reproduction and mortality rates, or age-specific individual demographic data. Depending on the degree of detail of the available information, we follow a weighted non-linear regression or a maximum likelihood approach. We discuss several criteria to determine the optimal number of states in the underlying TMAP. Our results improve the fit of an existing MBT model for human demography, and provide insights for the future conservation management of the threatened Chatham Island black robin population. (C) 2019 Elsevier Inc. All rights reserved