From 1 - 10 / 19
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    We hypothesised that New Zealand sea lions from Campbell Island/Motu Ihupuku of various sex and age classes would utilise the water column differently due to differing physiological constraints and therefore have different accessibility to prey resources. We tested whether sea lion diving behaviour varied in relation to (i) age and sex class, (ii) time of day and (iii) water depth. We also hypothesized that the proportion of benthic/pelagic diving, and consequently risk of fisheries interaction, would vary in relation to age and sex. Satellite telemetry tags were deployed on 25 NZSL from a range of age/sex classes recording dive depth, duration and location. Adult females and juveniles used inshore, benthic habitats, while sub-adult males also utilised benthic habitats, they predominantly used pelagic habitat at greater distances from the island. Adult females and juveniles exhibited shorter dives than the same age/sex classes at the Auckland Islands, suggesting a lower dive effort for these age/sex classes at Campbell Island.

  • In this study, 34 fledgling Fairy Prions (Pachyptila turtur) recovered during a wreck event in south-eastern Tasmania in 2022 were examined for ingested plastics (number, mass, type, colour, and particle size) and body condition (e.g., wing chord length).

  • Data to accompany publication on wild diet of southern rock lobster on the east coast of Tasmania. In this study we collected 64 lobsters and analysed the diet of each individual using stomach contents, stable isotope analysis and DNA identification of prey species in faecal samples.

  • Invasive mammal eradications are widely used for managing island ecosystems. However, tracking the outcomes of such large-scale, whole ecosystem projects is challenging and costly, and monitoring all components of an ecosystem is near impossible. Instead, indicators of ecosystem change may provide more practical and integrated measures of ecosystem response to eradications. As high-order marine predators, seabirds subsidise island ecosystems with nutrients isotopically enriched in nitrogen. Invasive mammals have caused a global decline of seabirds on islands, reducing this nutrient subsidisation. Following eradications, nitrogen stable isotope analysis may provide a useful and resource-efficient indicator of ecosystem functional change on eradicated islands. However, isotope ratios are affected by a myriad of factors, with potential sources of variation being introduced by spatial and temporal variation in sampling, and within and between different taxa and ecosystem components. To correctly attribute isotopic change to post-eradication ecosystem function change, these confounding variables need to be understood. To address this need, we analysed stable isotopes of nitrogen in soil, plant, spider, and seabird guano samples collected at different distances from seabird colonies and at different stages of the short-tailed shearwater breeding cycle on six island sites around south-eastern Tasmania, Australia. Across these cool, temperate islands we detected no temporal variability in δ15N throughout the breeding season. However, there was notable spatial variability in δ15N values. The effects of seabird-derived nutrient subsidisation were highly localised with high δ15N values found inside seabird colonies and then rapidly decreasing from the colony boundary. Higher δ15N values also occurred in areas of higher burrow density within a colony. Variability in δ15N values also existed both within and between ecosystem components. Our results highlight the importance of context dependency when using ecological indicators and have important implications for the design, implementation and interpretation of studies employing stable isotopes as indicators for ecosystem change. We provide recommendations for designing future stable isotope studies on seabird islands.

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    Satellite linked data loggers collecting temperature, conductivity, depth, location and time using Sea Mammal Research Unit tags.

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    This data contains at-sea GPS tracks of little penguins (Eudyptula minor) tagged at three colonies around Storm Bay, Tasmania (Boronia Beach, Wedge Island and Bruny Island Neck) over the 2015/16 summer breeding season. This data was collected as part of an honours thesis submitted in 2016.

  • We investigated the effects of seabird presence and seasonality on ground-active spider community structure (activity-density, family-level richness, age class and sex structure) and composition at the family-level across five short-tailed shearwater breeding islands around south-eastern Tasmania, Australia. Using 75 pitfall traps (15 per island), spiders were collected inside, near and outside seabird colonies on each island, at five different stages of the short-tailed shearwater breeding cycle over a year. 3. Pitfall traps were deployed for a total of 2,674 days, capturing 1,592 spiders from 26 families with Linyphiidae and Lycosidae the most common.

  • The Maugean Skate Zearaja maugeana is a micro-endemic species known from only two isolated estuaries, Bathurst and Macquarie Harbours in southwestern/western Tasmania. This constitutes one of the most limited distributions of any known extant elasmobranch. As a result, the species is listed as ‘Endangered’ under the Threatened Species Protection Act (Tasmania) and the Environmental Protection and Biodiversity Conservation Act (Commonwealth). Even though it was first discovered in Bathurst Harbour, most of what is known about the species comes from the Macquarie Harbour population. In fact, only four individuals have ever been reported in Bathurst Harbour, with the last known sighting occurring in 1992. This study aimed to use eDNA to determine the presence of the Maugean skate in Bathurst Harbour on the southwest coast of Tasmania. Water samples were collected within 1 m from the sea floor in Bathurst Harbour in November 2021 and February 2022, and in Macquarie Harbour (control samples) in December 2021. Samples were filtered using a self-preserving eDNA sampling system. Following each survey DNA from the samples was extracted and analysed through qPCR amplification. Mitochondrial primer pairs from two gene regions were used to detect the presence of Maugean skate DNA in the samples. Where possible, positive detections were sequenced, and their identity verified.

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    To quantify the winter diving behaviour and vertical habitat use of adult female Antarctic fur seals (Arctocephalus gazella) we tracked females using Wildlife Computers Time-Depth Recorders (TDRs). Females were captured towards the end of the lactation period (March/April) and the TDR was attached dorsally to the fur approximately 10 cm anterior to the rump using a two-part epoxy. TDRs were retrieved just prior to or after giving birth the following season. Data files were extracted from the tags using the Wildlife Computers software Instrument Helper.

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    The Seamap Australia National Benthic Habitat Layer (NBHL) is a compilation of benthic habitat datasets obtained from various sectors including research, government, industry and community sources, across Australia. These disparate datasets have been integrated into a single national-scale benthic habitat database, and classified uniformly under a national classification scheme implemented as a controlled vocabulary (https://vocabs.ardc.edu.au/viewById/129). Creation of this classification scheme complements work undertaken by the National Environmental Science Program (NESP) Marine Biodiversity Hub (Theme D). The Seamap Australia NBHL can be viewed, analysed and downloaded from the Seamap Australia data portal (https://seamapaustralia.org/map) – a national repository of seafloor habitat data and a decision support tool for marine managers. The NBHL is supplied through Web Mapping Services (WMS) alongside relevant contextual information, in an interactive mapping portal. All habitat datasets in the Seamap Australia data portal, including the NBHL and all local- to regional-scale contributing datasets, are available for download. The Seamap Australia NBHL is a data collection of national importance and highlights the diversity of benthic habitats across Australia’s marine estate. This is the first Australian habitat dataset that seamlessly consolidates data from each of Australia’s state and territory providers. This dataset should be considered a “live” asset and will continue to develop as more suitable validated habitat data becomes available for inclusion, and improvements in data collection and analysis techniques enhance its resolution and currency. The most current (2023) version of the data is available from the following endpoints: WMS: https://geoserver.imas.utas.edu.au/geoserver/seamap/wms WFS: https://geoserver.imas.utas.edu.au/geoserver/seamap/wfs Layer name: SeamapAus_National_Benthic_Habitat_Layer A download link for the full dataset is supplied in the “Online resources” section of this record, along with download links to older versions of the dataset. Note that data is now only available in Geodatabase (.gdb) format as it exceeds Shapefile size limits.