Bycatch in fisheries is a major threat to seabird populations worldwide, including in the eastern Pacific Ocean (EPO). Pelagic longline fisheries targeting tuna and swordfish globally account for tens of thousands of seabird mortalities annually. However, regional overlap patterns remain poorly quantified. To quantify spatial overlap with industrial and small-scale coastal longline fisheries in the EPO, we collated tracking data from 1993 to 2022 for albatrosses (12 species) and petrels (4 species) of high conservation concern. Utilization distributions (UDs) were calculated for each species split into breeding and non-breeding phases and according to age class and tag type, and overlaid with three pelagic longline effort datasets: industrial fisheries logbook data, Global Fishing Watch set-level data, and data on small-scale coastal fisheries. We also examined overlap of species UDs with the area where seabird bycatch mitigation is mandated by the Inter-American Tropical Tuna Commission (IATTC). Species with the highest fisheries-overlap, a proxy for exposure risk, included non-breeding adult black (Procellaria parkinsoni) and white-chinned petrels (P. aequinoctialis), Chatham (Thalassarche eremita), Buller’s (T. bulleri), Antipodean (Diomedea antipodensis antipodensis), and Salvin’s (T. salvini) albatrosses, and breeding waved albatrosses (Phoebastria irrorata). The IATTC mitigation area appeared to encompass most core habitat in the EPO for seabird species considered, with the notable exception being more tropically foraging black petrels, which largely occurred outside this area. Within this area, it is critical that mitigation measures follow the best available science, are updated as new science becomes available, and observer coverage is sufficient to monitor seabird bycatch rates and evaluate compliance.

Colonial central place foraging seabirds with a wide species range inhabit highly heterogenous habitats, which may result in colony-specific foraging behaviours. Simultaneously tracking seabirds from multiple colonies is key to elucidating factors influencing foraging behaviour and determining how species might respond to environmental perturbations. Here, we investigate the foraging behaviour of gentoo penguins (Pygoscelis papua) breeding at the Falkland Islands in relation to habitat availability and prey types. We examine the horizontal and vertical foraging distribution of 78 birds during two breeding seasons from three colonies, selected for their geographic separation and contrasting habitats. Through comparison of general foraging characteristics, we found that at each colony, penguins exhibited either pelagic foraging behaviour in the water column, or benthic foraging behaviour near to the sea floor. This was dictated by the surrounding bathymetry, with pelagic behaviour being associated with steeper surrounding slopes, and was in accordance with the known diet of birds. Then, using a hurdle model to predict dive intensity around each colony, we show that habitat suitability for all colonies declined once distance to the colony exceeded 30 km, while other variables had differing influences. At different colonies, the use of either pelagic or benthic foraging behaviours suggests that gentoo penguins have the capacity to respond to variable environmental conditions. However, given that foraging trips only reached mean maximum distances of 23.1 km ± 12.2 km from the colony during the breeding season, marine spatial planning efforts need to protect inshore waters around critical gentoo penguin colonies to effectively conserve the species.

Illex argentinus, commonly known as the Argentine shortfin squid, holds significant ecological and economic importance in the Patagonian Shelf ecosystem. Previous studies found the spatial and temporal distribution of I. argentinus linked to oceanographic features. This study used an extensive time series dataset, state-of the art Generalized-Additive-Mixed-Effect Models and novel approach of LSTM Neural Networks (NN) to analyse and forecast I. argentinus spatio-temporal abundance measured as Catch per Unit Effort. Furthermore, we tested for any lag between environmental variables and temporal abundance, specifically, 6 months previous to sampling. Higher temperatures and micronekton abundances had overall positive effects on CPUE at the time of sampling, whereas 6 months earlier, they had negative influences. Increased number of eddies within the wider FI zone and the Falkland Current had a positive impact on CPUE, other areas and the 6-month delay had negative influence on CPUE with increased eddy density. The overall best performing model was a NN model, which used temperature, zooplankton abundance and associated fronts for a weekly CPUE forecast with 3 weeks projection span. Apart from confirming findings from previous studies, that I. argentinus abundance is dependent on temperature and ocean fronts, we found more relevant predictor variables, e.g. micronekton abundance, sea surface height and number of eddies per area, which are influencing temporal and spatial abundance of I. argentinus. We showed that NNs are capable of forecasting temporal abundance, despite complexity of oceanographic processes on the Patagonian Shelf, coupled with complex migration patterns of I. argentinus.

Determining the environmental factors driving the foraging behaviour of marine top predators is crucial for assessing their ecological roles and resilience to environmental variability. This study examines the foraging strategies of female Australian fur seals (Arctocephalus pusillus doriferus; AUFS) during the austral autumn and winter (2008-2018) at Kanowna Island, south-eastern Australia, a region increasingly threatened by anthropogenic activities and environmental changes. Using animal-borne video cameras, GPS tracking, and dive behaviour loggers, encounters and captures of prey were analysed across 2022 recorded dives from 22 adult females provisioning pups. Benthic invertebrate cover was a key predictor of capture success, with the highest probabilities in densely covered areas, despite these not being the most frequently visited habitats. Encounter rates increased with depth, suggesting greater prey availability in deeper waters. Time of day significantly affected both encounters and captures with nocturnal periods showing the highest rates. These findings demonstrate that seafloor habitat complexity, depth and diel cycles simultaneously shape the prey fields of AUFS. The identification of specific habitat features linked to foraging behaviour improves the understanding of the ecological requirements of this central-place forager in a region undergoing rapid environmental change driven by anthropogenic pressures. Such insights are critical to anticipate potential impacts on prey availability and, consequently, on foraging efficiency and the ability of the species to adapt to future conditions.

Animal movement and population connectivity are key areas of uncertainty in efforts to understand and predict the spread of infectious disease. The emergence of highly pathogenic avian influenza (HPAI) in South America poses a significant threat to globally significant populations of colonial breeding marine predators in the South Atlantic. Yet, there is a poor understanding of which species or migratory pathways may facilitate disease spread. Compiling one of the largest available animal tracking datasets in the South Atlantic, we examine connectivity and inter‐population mixing for colonial breeding marine predators tagged at the Falkland Islands. We reveal extensive connectivity for three regionally dominant and gregarious species over the Patagonian Shelf. Black‐browed albatrosses (BBA), South American fur seals (SAFS) and Magellanic penguins (MAG) used coastal waters along the Atlantic coast of South America (Argentina and Uruguay). These behaviours were recorded at or in close proximity to breeding colonies and haul‐out areas with dense aggregations of marine predators. Transit times to and from the Falkland Islands to the continental coast ranged from 0.2–70 days, with 84% of animals making this transit within 4 days ‐ a conservative estimate for HPAI infectious period. Our findings demonstrate BBA, SAFS and MAG connectivity between the Falkland Islands and mainland South America over an expansive spatial network and numerous pathways, which has implications for infectious disease persistence, transmission and spread. This information is vital in supporting HPAI disease surveillance, risk assessment and marine management efforts across the region.

Marine Mammal ScienceEarly View NOTE Intraguild predation in pinnipeds: Southern sea lions prey upon adult female South American fur seals in the Falkland Islands Alastair M. M. Baylis, Corresponding Author Alastair M. M. Baylis [email protected] orcid.org/0000-0002-5167-0472 South Atlantic Environmental Research Institute, Falkland Islands Department of Biological Sciences, Macquarie University, Sydney, New South Wales, Australia Correspondence Alastair Baylis, South Atlantic Environmental Research Institute, Stanley, FIQQ1ZZ, Falkland Islands. Email: [email protected] Contribution: Conceptualization, Funding acquisition, ​Investigation, Methodology, Project administration, Writing - original draft, Writing - review & editingSearch for more papers by this authorKayleigh A. Jones, Kayleigh A. Jones British Antarctic Survey NERC, Cambridge, UK University of Exeter, Cornwall, UK Contribution: Funding acquisition, ​Investigation, Methodology, Writing - original draft, Writing - review & editingSearch for more papers by this authorRachael A. Orben, Rachael A. Orben Marine Mammal Institute, Department of Fisheries, Wildlife, and Conservation Sciences, Oregon State University, Hatfield Marine Science Center, Newport, Oregon Contribution: Conceptualization, ​Investigation, Methodology, Project administration, Writing - original draft, Writing - review & editingSearch for more papers by this author Alastair M. M. Baylis, Corresponding Author Alastair M. M. Baylis [email protected] orcid.org/0000-0002-5167-0472 South Atlantic Environmental Research Institute, Falkland Islands Department of Biological Sciences, Macquarie University, Sydney, New South Wales, Australia Correspondence Alastair Baylis, South Atlantic Environmental Research Institute, Stanley, FIQQ1ZZ, Falkland Islands. Email: [email protected] Contribution: Conceptualization, Funding acquisition, ​Investigation, Methodology, Project administration, Writing - original draft, Writing - review & editingSearch for more papers by this authorKayleigh A. Jones, Kayleigh A. Jones British Antarctic Survey NERC, Cambridge, UK University of Exeter, Cornwall, UK Contribution: Funding acquisition, ​Investigation, Methodology, Writing - original draft, Writing - review & editingSearch for more papers by this authorRachael A. Orben, Rachael A. Orben Marine Mammal Institute, Department of Fisheries, Wildlife, and Conservation Sciences, Oregon State University, Hatfield Marine Science Center, Newport, Oregon Contribution: Conceptualization, ​Investigation, Methodology, Project administration, Writing - original draft, Writing - review & editingSearch for more papers by this author First published: 29 December 2023 https://doi.org/10.1111/mms.13098Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat REFERENCES Andersson, K., Norman, D., & Werdelin, L. 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Direct interactions between marine mammals and commercial fisheries are a worldwide conservation challenge. Observer programmes remain the most effective and reliable method for collecting data on these interactions. In the Falkland Islands-home to globally significant seal populations and commercial squid fisheries, seal-fishery interactions have escalated in recent years, prompting management concerns. Complete observer coverage within the squid fishery presents a valuable opportunity to investigate the nature, extent, and drivers of these interactions. Integrating multi-year observer records with extensive ancillary (i.e. vessel logbook and oceanographic) datasets, we examine the operational and environmental factors influencing the occurrence of seal-fishery interactions. Our findings show interactions most frequently occur in the main squid fishing grounds during trawls associated with high catch quantities. Assessment of long-term catch data (both finfish and squid) also suggests the increase in seal-fishery interactions may be caused by collapses in dominant finfish stocks over the past 20 years, constricting foraging resources available to seals. Taken together, our findings indicate resource competition may be a mechanism of interactions. To help mitigate this issue, we advocate for the development of ecosystem-based fisheries management, which considers the trophic effects of fishing practices and the energetic requirements of local marine predator populations.

The Falkland Islands marine environment host a mix of temperate and subantarctic species. This review synthesizes baseline information regarding ontogenetic migration patterns 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 regional oceanographic dynamics that bring together different water masses, resulting in high primary production which supports high biomass in the rest of the food web. Further, many species, including those of commercial interest, show complex ontogenetic migrations that separate spawning, nursing, and feeding grounds spatially and temporally, producing food web connections across space and time. The oceanographic and biological dynamics may make the ecosystem vulnerable to climatic changes in temperature and shifts in the surrounding area. The Falkland marine ecosystem has been understudied and various functional groups, deep-sea habitats and inshore-offshore connections are poorly understood and should be priorities for further research.

Interactions between seals and commercial fisheries can pose a significant threat to the conservation status of seal populations. In the Falkland Islands, home to over 50 % of the global South American fur seal (SAFS) population, there has been a dramatic (∼ 900 %) increase in the number of SAFS-fishery interactions in recent years. However, significant knowledge gaps regarding SAFS spatiotemporal foraging behaviour and habitat use hinders our capacity to assess the ecological mechanisms underpinning these interactions. In this study, we investigate the spatial overlap between SAFS foraging effort and commercial squid and finfish trawl fisheries in the Falkland Island Exclusive Economic Zone (EEZ). By spatially integrating two years of SAFS horizontal and vertical movement data with contemporaneous trawl-by-trawl information from the Falkland Islands fishing fleet, we examine whether SAFS concentrate their foraging effort in areas associated with greater squid and finfish catch quantities. Our findings reveal a marked spatial overlap between SAFS foraging effort and commercial trawling activity within the Falkland Islands EEZ, particularly in areas associated with Patagonian longfin squid (Doryteuthis gahi) and common hake (Merluccius hubbsi). Across the various metrics of foraging effort (summarised dive activity) examined, we found SAFS performed a greater number of dives, travelled greater vertical distances and performed deeper dives in intensively fished areas. These results suggest SAFS forage in the same habitats targeted by commercial squid and finfish fisheries, where they compete for demersal resources by performing a high frequency of deep dives. The implications of our findings are discussed within the broader context of local prey-field dynamics and fisheries-management. This study represents one of the most comprehensive investigations of SAFS movement ecology and advances our understanding of seal-fishery interactions in the Falkland Islands EEZ – a topic of increasing management concern. Importantly, this work can support conservation efforts for this globally significant SAFS population and contribute to long-term marine management objectives of the Falkland Islands fishery.

Hybridization is widespread and constitutes an important source of genetic variability and evolution. In animals, its role in generating novel and independent lineages (hybrid speciation) has been strongly debated, with only a few cases supported by genomic data. The South American fur seal (SAfs) Arctocephalus australis is a marine apex predator of Pacific and Atlantic waters, with a disjunct set of populations in Peru and Northern Chile [Peruvian fur seal (Pfs)] with controversial taxonomic status. We demonstrate, using complete genome and reduced representation sequencing, that the Pfs is a genetically distinct species with an admixed genome that originated from hybridization between the SAfs and the Galapagos fur seal (Arctocephalus galapagoensis) ~400,000 years ago. Our results strongly support the origin of Pfs by homoploid hybrid speciation over alternative introgression scenarios. This study highlights the role of hybridization in promoting species-level biodiversity in large vertebrates.

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 species have undergone population declines over the past century, potentially due to changing oceanography and prey availability over the important winter months. We used light-based geolocation tracking data for 485 individuals deployed between 2006 and 2020 across 10 of the major breeding locations for five taxa of Eudyptes penguins. We used boosted regression tree modelling to quantify post-moult habitat preference for southern rockhopper (E. chrysocome), eastern rockhopper (E. filholi), northern rockhopper (E. moseleyi) and macaroni/royal (E. chrysolophus and E. schlegeli) penguins. We then modelled their redistribution under two climate change scenarios, representative concentration pathways RCP4.5 and RCP8.5 (for the end of the century, 2071-2100). As climate forcings differ regionally, we quantified redistribution in the Atlantic, Central Indian, East Indian, West Pacific and East Pacific regions. We found sea surface temperature and sea surface height to be the most important predictors of current habitat for these penguins; physical features that are changing rapidly in the Southern Ocean. Our results indicated that the less severe RCP4.5 would lead to less habitat loss than the more severe RCP8.5. The five taxa of penguin may experience a general poleward redistribution of their preferred habitat, but with contrasting effects in the (i) change in total area of preferred habitat under climate change (ii) according to geographic region and (iii) the species (macaroni/royal vs. rockhopper populations). Our results provide further understanding on the regional impacts and vulnerability of species to climate change.

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 Atlantic deep sea is an undersampled region that hosts unique and globally important faunal assemblages. To date, our knowledge of these assemblages has been predominantly based on ex situ analysis of scientific trawl and fisheries bycatch specimens, limiting our ability to characterise faunal assemblages. Incidental sampling and fisheries bycatch data indicate that the Falkland Islands deep sea hosts a diversity of fauna, including vulnerable marine ecosystem (VME) indicator taxa. To increase our knowledge of Southwest Atlantic deep-sea epibenthic megafauna assemblages, benthic imagery, comprising 696 images collected along the upper slope (1070–1880 m) of the Falkland Islands conservation zones (FCZs) in 2014, was annotated, with epibenthic megafauna and substrata recorded. A suite of terrain derivatives were also calculated from GEBCO bathymetry and oceanographic variables extracted from global models. The environmental conditions coincident with annotated image locations were calculated, and multivariate analysis was undertaken using 288 ‘sample’ images to characterize faunal assemblages and discern their environmental drivers. Three main faunal assemblages representing two different sea pen and cup coral assemblages, and an assemblage characterised by sponges and Stylasteridae, were identified. Subvariants driven by varying dominance of sponges, Stylasteridae, and the stony coral, Bathelia candida, were also observed. The fauna observed are consistent with that recorded for the wider southern Patagonian Slope. Several faunal assemblages had attributes of VMEs. Faunal assemblages appear to be influenced by the interaction between topography and the Falkland Current, which, in turn, likely influences substrata and food availability. Our quantitative analyses provide a baseline for the southern Patagonian shelf/slope environment of the FCZs, against which to compare other assemblages and assess environmental drivers and anthropogenic impacts.

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 Passage to forage in Antarctic waters south of the Polar Front. We deployed miniature GPS dataloggers to track Thin-billed prions in the Falkland Islands during incubation (3 seasons) and chick-rearing (2 seasons). Thin-billed Prions had a wide distribution during incubation, covering latitudes between 43 and 60° S, with trip lengths of ca. 2000 km over seven days, on average. Thin-billed Prions from two nearby sites (60 km apart) were spatially segregated in their incubation trips, with New Island Thin-billed Prions foraging over the Patagonian Shelf, compared to Thin-billed Prions from Bird Island, that foraged in the region of the Polar Front. During chick-rearing, Thin-billed Prions from New Island undertook both long trips to the Patagonian Shelf and south of the Polar Front (30% of trips were 5–11 days), and short trips (70% of trips were 1–4 days) when they foraged more locally, including in inshore waters around the Falkland Islands. Females carried out more trips to distant sites. Thus, Thin-billed showed a high flexibility in foraging areas, habitats and foraging trip durations, which enable them to benefit from both, temperate and Antarctic environments.

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 across five taxa, chosen to reflect the span of home range size in highly mobile marine megafauna, we show most MPAs are too small to encompass complete home ranges of most species. Based on size alone, 40% of existing MPAs could encompass the home ranges of the smallest ranged species, while only < 1% of existing MPAs could encompass those of the largest ranged species. Further, where home ranges and MPAs overlapped in real geographic space, MPAs encompassed < 5% of core areas used by all species. Despite most home ranges of mobile marine megafauna being much larger than existing MPAs, we demonstrate how benefits from MPAs are still likely to accrue by targeting seasonal aggregations and critical life history stages and through other management techniques.

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 fisheries and island economies. However, robust blue carbon research is often limited at the scale of regional governance and management, lacking both incentives and facilitation of policy-integration. The remote and highly biodiverse coastal ecosystems and surrounding continental shelf can be used to better inform long-term ecosystem-based management in the vast South Atlantic Ocean and sub-Antarctic, to synergistically protect both unique biodiversity and inform on the magnitude of nature-based benefits they provide. Understanding key ecosystem information such as their location, extent, and condition of habitat types, will be critical in understanding carbon pathways to sequestration, threats to this, and vulnerability. This paper considers the current status of blue carbon data and information available, and what is still required before blue carbon can be used as a conservation management tool integrated in national Marine Spatial Planning (MSP) initiatives. Our research indicates that the data and information gathered has enabled baselines for a number of different blue carbon ecosystems, and indicated potential threats and vulnerability that need to be managed. However, significant knowledge gaps remain across habitats, such as salt marsh, mudflats and the mesophotic zones, which hinders meaningful progress on the ground where it is needed most.

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 G(i)* hotspots were calculated based on the number of individuals in grid cells for each species and for phylogenetic groups (nine pinnipeds, three cetaceans, all species) and areas with high species richness were identified for summer (Jun-Nov), winter (Dec-May) and the entire year. Seasonal habitat differences among species' hotspots were investigated using Principal Component Analysis. Results Hotspots and areas with high species richness occurred within the Arctic continental-shelf seas and within the marginal ice zone, particularly in the "Arctic gateways" of the north Atlantic and Pacific oceans. Summer hotspots were generally found further north than winter hotspots, but there were exceptions to this pattern, including bowhead whales in the Greenland-Barents Seas and species with coastal distributions in Svalbard, Norway and East Greenland. Areas with high species richness generally overlapped high-density hotspots. Large regional and seasonal differences in habitat features of hotspots were found among species but also within species from different regions. Gap analysis (discrepancy between hotspots and IUCN ranges) identified species and regions where more research is required. Main conclusions This study identified important areas (and habitat types) for Arctic marine mammals using available biotelemetry data. The results herein serve as a benchmark to measure future distributional shifts. Expanded monitoring and telemetry studies are needed on Arctic species to understand the impacts of climate change and concomitant ecosystem changes (synergistic effects of multiple stressors). While efforts should be made to fill knowledge gaps, including regional gaps and more complete sex and age coverage, hotspots identified herein can inform management efforts to mitigate the impacts of human activities and ecological changes, including creation of protected areas.

Although many penguin species migrate during the non‐breeding period, Gentoo Penguins 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 movements of Gentoo Penguins from five breeding colonies at the Falkland Islands, globally one of the largest Gentoo Penguin breeding populations. Gentoo Penguin movement patterns during the non‐breeding period were complex, which likely reflects a high degree of foraging plasticity. Specifically, considerable individual variation existed in foraging trip distance, duration and fidelity to deployment location. For example, maximum foraging trip distance for individual penguins ranged from 64 to 600 km from the colony location (or 480 km from the nearest point on land), and maximum foraging trip duration ranged from 5.7 to 24.8 days. Gentoo Penguin foraging trip distance and duration at the Falkland Islands far exceeded those reported at other locations during the non‐breeding period, and challenge the inshore, diurnal feeding stereotype. Gentoo Penguins also frequently moved between breeding colonies within the Falkland Islands archipelago, but typically returned to their respective colonies, although not necessarily on consecutive foraging trips. Extended movements highlight Gentoo Penguin breeding dispersal capability, which might play a crucial role in population dynamics and gene flow.

Knowledge of the factors shaping the foraging behaviour of species is central to understanding their ecosystem role and predicting their response to environmental variability. To maximise survival and reproduction, foraging strategies must balance the costs and benefits related to energy needed to pursue, manipulate, and consume prey with the nutritional reward obtained. While such information is vital for understanding how changes in prey assemblages may affect predators, determining these components is inherently difficult in cryptic predators. The present study used animal-borne video data loggers to investigate the costs and benefits related to different prey types for female Australian fur seals (Arctocephalus pusillus doriferus), a primarily benthic foraging species in the low productivity Bass Strait, south-eastern Australia. A total of 1,263 prey captures, resulting from 2,027 prey detections, were observed in 84.5 h of video recordings from 23 individuals. Substantial differences in prey pursuit and handling times, gross energy gain and total energy expenditure were observed between prey types. Importantly, the profitability of prey was not significantly different between prey types, with the exception of elasmobranchs. This study highlights the benefit of animal-borne video data loggers for understanding the factors that influence foraging decisions in predators. Further studies incorporating search times for different prey types would further elucidate how profitability differs with prey type.