Alastair M. M. Baylis

South Atlantic Environmental Research Institute | SAERI

The need to manage otariid populations has necessitated the development of a wide range of capture methods. Chemical restraint by remote drug delivery (i.e., darting) is a highly selective method that can be used to facilitate otariid capture in a range of scenarios, when other methods may be impracticable. However, the risks associated with dartin...

https://albaylis.files.wordpress.com/2015/10/baylis_ecology-2015.pdf Considerable uncertainties often surround the causes of long-term changes in population abundance. One striking example is the precipitous decline of southern sea lions (SSL) (Otaria flavescens) at the Falkland Islands - from 80,555 pups in the mid 1930s to just 5,506 pups in 196...

Despite global declines in the abundance of marine predators, knowledge of foraging ecology, necessary to predict the ecological consequences of large changes in marine predator abundance, remains enigmatic for many species. Given populations suffering severe declines are of conservation concern, we examined the foraging ecology of southern sea lio...

Conditions experienced during the nonbreeding period have profound long-term effects on individual fitness and survival. Therefore, knowledge of habitat use during the non- breeding period can provide insights into processes that regulate populations. At the Falkland Islands, the habitat use of South American sea lions (Otaria flavescens) during th...

The Patagonian Shelf Large Marine Ecosystem supports high levels of biodiversity and endemism and is one of the most productive marine ecosystems in the world. Despite the important role marine predators play in structuring ecosystems, areas of high diversity where multiple predators congregate remains poorly known on the Patagonian Shelf. Here, we...

The Falkland Islands marine environment host a mix of temperate and subantarctic spe-cies. This review synthesizes baseline information regarding ontogenetic migration pat-terns and trophic interactions in relation to oceanographic dynamics of the Falkland Shelf, which is useful to inform ecosystem modelling. Many species are strongly influenced by...

Pelagic seabirds cover large distances efficiently and thus may reach a variety of marine habitats during breeding. Previous studies using stable isotope data and geolocators suggested that Thin-billed Prions breeding in the Falkland Islands in the Southwest Atlantic may forage in temperate waters over the Patagonian Shelf or cross the Drake Passag...

Anthropogenic climate change is resulting in spatial redistributions of many species. We assessed the potential effects of climate change on an abundant and widely distributed group of diving birds, Eudyptes penguins, which are the main avian consumers in the Southern Ocean in terms of biomass consumption. Despite their abundance, several of these...

Deep-sea environments face increasing pressure from anthropogenic exploitation and climate change, but remain poorly studied. Hence, there is an urgent need to compile quantitative baseline data on faunal assemblages, and improve our understanding of the processes that drive faunal assemblage composition in deep-sea environments. The Southwest Atla...

Marine protected areas (MPAs), particularly large MPAs, are increasing in number and size around the globe in part to facilitate the conservation of marine megafauna under the assumption that large-scale MPAs better align with vagile life histories; however, this alignment is not well established. Using a global tracking dataset from 36 species acr...

Ecosystem-based conservation that includes carbon sinks, alongside a linked carbon credit system, as part of a nature-based solution to combating climate change, could help reduce greenhouse gas levels and therefore the impact of their emissions. Blue carbon habitats and pathways can also facilitate biodiversity retention, aiding sustainable fisher...

Aim Identify hotspots and areas of high species richness for Arctic marine mammals. Location Circumpolar Arctic. Methods A total of 2115 biologging devices were deployed on marine mammals from 13 species in the Arctic from 2005 to 2019. Getis‐Ord Gi* hotspots were calculated based on the number of individuals in grid cells for each species and fo...

Paper blog: https://blogs.oregonstate.edu/seabirdoceanographylab/2021/08/02/predators-and-marine-managed-areas/ Static (fixed-boundary) protected areas are key ocean conservation strategies, and marine higher predator distribution data can play a leading role toward identifying areas for conservation action. The Falkland Islands are a globally si...

Individual specialization, which describes whether populations are comprised of dietary generalists or specialists, has profound ecological and evolutionary implications. However, few studies have quantified individual specialization within and between sympatric species that are functionally similar but have different foraging modes. We assessed th...

Although many penguin species migrate during the non-breeding period, Gentoo Pen- guins Pygoscelis papua are year-round residents. Despite being characterized as inshore feeders, the at-sea spatial usage of Gentoo Penguins during the non-breeding period, when central place foraging constraints are relaxed, is poorly understood. Here, we tracked the...

Natural selection should favour strategies that maximise reproductive success. Females may use different resources during progressive stages of reproduction according to energetic demands, behavioural constraints and prey availability. We used South American fur seal, Arctocephalus australis australis, pup whisker isotope values as proxies for mate...

Although grey seals (Halichoerus grypus) are the focus of considerable research effort throughout much of their North Atlantic breeding range, little is known about grey seal movement ecology in Iceland. This is surprising given the long history of grey seal exploitation in Iceland and because grey seals are common bycatch in commercial fisheries....

Top-order predators play an important role in the structure and function of marine ecosystems. Optimal foraging theory predicts that predators will utilise foraging strategies that maximise their net energetic intake, and consequently, individuals within a population may utilise alternate strategies to target different prey resources. The present s...

1. South American fur seals (Arctocephalus australis australis) are widely distributed, yet surprisingly little is known about their ecology. In particular, population data are sparse and outdated for many breeding locations, including the Falkland Islands. Data deficiency impedes the development of coherent conservation and management strategies....

Little is known about the movement ecology of male South American fur seals (SAFS; Arctocephalus australis). To begin to address knowledge gaps we used satellite telemetry to track four adult male SAFS at the Falkland Islands over the non-breeding period, from May to December. Our aims were to describe adult male SAFS habitat use and quantify spati...

Optimal foraging theory predicts that predators will employ strategies that maximise their net energetic return. Foraging site fidelity (the re-use of a prior foraging area) is assumed to be beneficial, because it facilitates direct travel to foraging areas and familiarity with a foraging area may confer energetic advantages over the lifetime of an...

The implicit assumption of many ecological studies is that animal behaviour and resource use is geographically uniform. However, central place foraging species often have geographically isolated breeding colonies that are associated with markedly different habitats. South American fur seals (Arctocephalus australis) (SAFS) are an abundant and widel...

Marine Spatial Planning (MSP) is becoming a key management approach throughout the world. The process includes the mapping of how humans and wildlife use the marine environment to inform the development of management measures. An integrated multi-species approach to identifying key areas is important for MSP because it allows managers a global repr...

Significance Understanding the key drivers of animal movement is crucial to assist in mitigating adverse impacts of anthropogenic activities on marine megafauna. We found that movement patterns of marine megafauna are mostly independent of their evolutionary histories, differing significantly from patterns for terrestrial animals. We detected a rem...

Marine species occupy broad geographical ranges that encompass varied habitats. Accordingly, resource availability is likely to differ across a species range and, in-turn, this may influence the degree of dietary specialization. Gentoo penguins Pygoscelis papua are generalist predators occupying a range of habitats with a large breeding range exten...

Marine predators play an important role in the structure and function of the ecosystems they inhabit. Knowing where marine predators forage and how individual strategies vary, therefore, has important implications for our understanding of ecosystem processes as well as species management and conservation. However, within fur seals and sea lions, kn...

Overview of species distribution modelling approach used to identify probable location of Gentoo Penguins at unsampled locations.

Electronic supplementary material, figure S1. Results of the Structure [38] analysis showing average log-likelihood value values based on five replicates for each value of K, the hypothesized number of clusters in the data. Electronic supplementary material, table S1. Numbers of sea lion tissue samples collected and successfully sequenced for the m...

Understanding the causes of population decline is crucial for conservation management. We therefore used genetic analysis both to provide baseline data on population structure and to evaluate hypotheses for the catastrophic decline of the South American sea lion (Otaria flavescens) at the Falkland Islands (Malvinas) in the South Atlantic. We genoty...

Uncertainty plots derived from the model-based clustering of southern sea lion pup stable isotopes, implemented within the R Package ‘Mclust’. The ellipses shown represent each cluster, with the smallest grey dots representing the lowest uncertainty and large black dots, the largest uncertainty (quantiles are 0.75,0.95 –the default quantiles used i...

Isotope data for 65 southern sea lion pups sampled from breeding colonies around the Falkland Islands (see ‘Methods’ for details). (DOCX)

Individuals within populations often differ substantially in habitat use, the ecological consequences of which can be far reaching. Stable isotope analysis provides a convenient and often cost effective means of indirectly assessing the habitat use of individuals that can yield valuable insights into the spatiotemporal distribution of foraging spec...

Our understanding of how air-breathing marine predators cope with environmental variability is limited by our inadequate knowledge of their ecological and physiological parameters. Due to their wide distribution along both coasts of the sub-continent, South American sea lions (Otaria byronia) provide a valuable opportunity to study the behavioral a...

Sexual segregation in habitat use is widely reported in many taxa and can profoundly influence the distribution and behaviour of animals. However, our knowledge of the mechanisms driving sexual segregation is still in its infancy (particularly in marine taxa) and the influence of extrinsic factors in mediating the expression of sex differences in f...

Estimating the degree of individual specialisation is likely to be sensitive to the methods used, as they record individuals’ resource use over different time-periods. We combined animal-borne video cameras, GPS/TDR loggers and stable isotope values of plasma, red cells and sub-sampled whiskers to investigate individual foraging specialisation in f...

Dive characteristics and dive shape are often used to infer foraging success in pinnipeds. However, these inferences have not been directly validated in the field with video, and it remains unclear if this method can be applied to benthic foraging animals. This study assessed the ability of dive characteristics from time-depth recorders (TDR) to pr...

An understanding of resource use and the factors driving their requirement are critical for the conservation and management of a species. This may be particularly so for populations of generalist species that may in fact be more or less specialised at the sub-population level, particularly, when these sub-populations occupy different habitats. The...

The Falkland Islands now globally hold the largest population of Gentoo penguins, Pygoscelis papua. Understanding the mechanisms driving their foraging ecology at this archipelago is therefore largely relevant to the species as a whole, and is important for effective conservation management. We use the first combination of TDR, GPS and animal borne...

The Falkland Islands now globally hold the largest population of Gentoo penguins, Pygoscelis papua. Understanding the mechanisms driving their foraging ecology at this archipelago is therefore largely relevant to the species as a whole, and is important for effective conservation management. We use the first combination of TDR, GPS and animal borne...

Knowledge of diet is critical in interpreting the ecological roles of marine top predators and provides information towards their conservation and management. The Falkland Islands hold the largest number of breeding gentoo penguins. Yet knowledge of gentoo penguin diet at the Falk-lands is limited to either broad taxonomic divisions of prey items o...

While sexual segregation is expected in highly dimorphic species, the local environment isa major factor driving the degree of resource partitioning within a population. Sexual andindividual niche segregation was investigated in the Australian fur seal (Arctocephaluspusillus doriferus), which is a benthic foraging species restricted to the shallow...

The Falkland Islands now globally hold the largest population of Gentoo penguins, Pygoscelis papua. Understanding the mechanisms driving their foraging ecology at this archipelago is therefore largely relevant to the species as a whole, and is important for effective conservation management. We use the first combination of TDR, GPS and animal borne...

Foraging site fidelity has profound consequences for individual fitness, population processes and the effectiveness of species conservation measures. Accordingly, quantifying site fidelity has become increasingly important in animal movement and habitat selection studies. To assess foraging site fidelity in king penguins (Aptenodytes patagonicus) b...

Whilst there is good evidence for negative impacts of introduced rat species on island ecosystems, the effects of house mice (Mus musculus) are generally less well documented. In some situations, introduced house mice can exert severe impacts, particularly where this is the only introduced mammal. Here, we examine the distribution, relative abundan...

Aim: Competition for food among populations of closely related species and conspecifics that occur in both sympatry and parapatry can be reduced by interspecific and intraspecific spatial segregation. According to predictions of niche partitioning, segregation is expected to occur at habitat boundaries among congeners and within habitats among con...

An understanding of resource use and the factors driving their requirement are critical for the conservation and management of a species. This may be particularly so for populations of generalist species that may in fact be more or less specialised at the sub-population level, particularly, when these sub-populations occupy different habitats. The...

The Falkland Islands currently supports one of the largest Southern Rockhopper Penguin (Eudyptes c. chrysocome) populations. Archipelago-wide censuses conducted in 2000 and 2005 revealed that the number of breeding pairs had declined by 30 % during this period. To establish whether the breeding population continued to decline, an archipelago-wide c...

We used the Ecopath with Ecosim software to develop a trophic mass-balance model of the eastern Great Australian Bight ecosystem, off southern Australia. Results provide an ecosystem perspective of Australia's largest fishery, the South Australian sardine fishery, by placing its establishment and growth in the context of other dynamic changes in th...

The fourth archipelago-wide census of Gentoo Penguins Pygoscelis papua breeding at the Falkland Islands was conducted from 24 October to 8 December 2010. The number of Gentoo Penguins breeding in 2010 was estimated to be 132 321 ± 2 015, the highest number of breeding pairs recorded for this species at the Falkland Islands since the first survey in...

After an extended period of sporadic sightings of small numbers of king penguins at the Falkland Islands, they established themselves on Volunteer Point, situated at the north-east of the islands, by the late 1970s. By 1980, a small breeding population was present which yielded some 40 fledglings during that same year. Since 1991, the population ha...

Wide-ranging marine central place foragers often exhibit foraging site fidelity to oceanographic features over differing spatial scales (i.e., localized coastal upwellings and oceanic fronts). Few studies have tested how the degree of site fidelity to foraging areas varies in relation to the type of ocean features used. In order to determine how fo...

Detecting and predicting how populations respond to environmental variability are eminent challenges in conservation research and management. This is particularly true for wildlife populations at high latitudes, many of which demonstrate changes in population dynamics associated with global warming. The Falkland Islands (Southwest Atlantic) hold on...

A hairless adult male southern sea lion (Otaria flavescens) was sighted at Sea Lion Island, Falkland Islands, on the 14th of August 2009. The sea lion was observed on several further occasions and was defending a small harem consisting of four females. To our knowledge, this is the first report of an apparently healthy sea lion being entirely hairl...