ORCID Profile
0000-0002-8293-0863
Current Organisations
Antarctic Climate and Ecosystem Co-operative Research Centre
,
University of Tasmania
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: The Royal Society
Date: 03-2023
DOI: 10.1098/RSOS.221635
Abstract: Developmental differences in vital rates are especially profound in polygamous mating systems. Southern elephant seals ( Mirounga leonina ) are highly dimorphic and extremely polygynous marine mammals. A demographic model, supported by long-term capture–mark–recapture records, investigated the influence of sex and age on survival in this species. The study revealed clear differences between female and male age-dependent survival rates. Overall juvenile survival estimates were stable around 80–85% for both sexes. However, male survival estimates were 5–10% lower than females in the same age classes until 8 years of age. At this point, male survival decreased rapidly to 50% ± 10% while female estimates remained constant at 80% ± 5%. Different energetic requirements could underpin intersex differences in adult survival. However, the species' strong sexual dimorphism erges during early juvenile development when sex-specific survival rates were less distinct. Maximizing growth is especially advantageous for males, with size being a major determinant of breeding probability. Maturing males may employ a high-risk high-reward foraging strategy to compensate for extensive sexual selection pressures and sex-specific energetic needs. Our findings suggest sex-specific adult survival is a result of in situ ecological interactions and evolutionary specialization associated with being a highly polygynous marine predator.
Publisher: Elsevier BV
Date: 12-2017
Publisher: Springer Science and Business Media LLC
Date: 12-12-2019
DOI: 10.1038/S41598-019-55152-4
Abstract: Mesopelagic fish and squid occupy ocean depths extending below the photic zone and their vertical migrations represent a massive pathway moving energy and carbon through the water column. Their spatio-temporal distribution is however, difficult to map across remote regions particularly the vast Southern Ocean. This represents a key gap in understanding biogeochemical processes, marine ecosystem structure, and how changing ocean conditions will affect marine predators, which depend upon mesopelagic prey. We infer mesopelagic prey vertical distribution and relative abundance in the Indian sector of the Southern Ocean (20° to 130°E) with a novel approach using predator-derived indices. Fourteen years of southern elephant seal tracking and e data, from the open ocean between the Antarctic Polar Front and the southern Antarctic Circumpolar Current front, clearly show that the vertical distribution of mesopelagic prey is influenced by the physical hydrographic processes that structure their habitat. Mesopelagic prey have a more restricted vertical migration and higher relative abundance closer to the surface where Circumpolar Deep Water rises to shallower depths. Combining these observations with a future projection of Southern Ocean conditions we show that changes in the coupling of surface and deep waters will potentially redistribute mesopelagic prey. These changes are small overall, but show important spatial variability: prey will increase in relative abundance to the east of the Kerguelen Plateau but decrease to the west. The consequences for deep- ing specialists such as elephant seals and whales over this time scale will likely be minor, but the changes in mesoscale vertical energy flow have implications for predators that forage within the mesopelagic zone as well as the broader pelagic ecosystem.
Publisher: Springer Science and Business Media LLC
Date: 10-12-2021
Publisher: Wiley
Date: 09-04-2201
DOI: 10.1111/ECOG.04939
Publisher: Wiley
Date: 16-07-2022
DOI: 10.1111/TPJ.15889
Abstract: Spruces ( Picea spp.) are coniferous trees widespread in boreal and mountainous forests of the northern hemisphere, with large economic significance and enormous contributions to global carbon sequestration. Spruces harbor very large genomes with high repetitiveness, h ering their comparative analysis. Here, we present and compare the genomes of four different North American spruces: the genome assemblies for Engelmann spruce ( Picea engelmannii ) and Sitka spruce ( Picea sitchensis ) together with improved and more contiguous genome assemblies for white spruce ( Picea glauca ) and for a naturally occurring introgress of these three species known as interior spruce ( P. engelmannii × glauca × sitchensis ). The genomes were structurally similar, and a large part of scaffolds could be anchored to a genetic map. The composition of the interior spruce genome indicated asymmetric contributions from the three ancestral genomes. Phylogenetic analysis of the nuclear and organelle genomes revealed a topology indicative of ancient reticulation. Different patterns of expansion of gene families among genomes were observed and related with presumed ersifying ecological adaptations. We identified rapidly evolving genes that harbored high rates of non‐synonymous polymorphisms relative to synonymous ones, indicative of positive selection and its hitchhiking effects. These gene sets were mostly distinct between the genomes of ecologically contrasted species, and signatures of convergent balancing selection were detected. Stress and stimulus response was identified as the most frequent function assigned to expanding gene families and rapidly evolving genes. These two aspects of genomic evolution were complementary in their contribution to ergent evolution of presumed adaptive nature. These more contiguous spruce giga‐genome sequences should strengthen our understanding of conifer genome structure and evolution, as their comparison offers clues into the genetic basis of adaptation and ecology of conifers at the genomic level. They will also provide tools to better monitor natural genetic ersity and improve the management of conifer forests. The genomes of four closely related North American spruces indicate that their high similarity at the morphological level is paralleled by the high conservation of their physical genome structure. Yet, the evidence of ergent evolution is apparent in their rapidly evolving genomes, supported by differential expansion of key gene families and large sets of genes under positive selection, largely in relation to stimulus and environmental stress response.
Publisher: Springer Science and Business Media LLC
Date: 21-09-2022
Publisher: American Geophysical Union (AGU)
Date: 19-06-2021
DOI: 10.1029/2020GL091206
Abstract: Antarctic krill (krill) are important within Southern Ocean ecosystems and support an expanding fishery. Toward understanding krill's response to environmental change, it is necessary to identify regions that support high krill larval production (spawning habitat). We develop a mechanistic model combining thermal and food requirements for krill egg production, with predation pressure post‐spawning, to predict regions of high‐quality spawning habitat. We optimize our model regionally and generate circumpolar predictions of spawning habitat quality. Our results indicate the southwest Atlantic accounts for almost half of all predicted high‐quality spawning habitat. Small‐scale management units (SSMUs) around the Antarctic Peninsula had high coverage of high‐quality spawning habitat. In contrast, the remaining SSMUs (except around South Georgia) were poorly covered, suggestive of population sinks reliant on input from external sources upstream. This implies strong potential for downstream impacts of fishing in key spawning areas, with implications for management of SSMUs and the krill fishery.
Publisher: Springer Science and Business Media LLC
Date: 28-01-2019
Publisher: Springer Science and Business Media LLC
Date: 18-04-2020
Publisher: Springer Science and Business Media LLC
Date: 18-05-2020
Publisher: Elsevier BV
Date: 04-2018
Publisher: Research Square Platform LLC
Date: 02-02-2022
DOI: 10.21203/RS.3.RS-1255733/V1
Abstract: Antarctic krill are a key Southern Ocean species whose success is attributed to their adaption to the extreme polar seasonality. Overwinter sea-ice presence and characteristics exert a strong control on larval survival and subsequent recruitment. Our understanding of the mechanisms through which sea ice influences survival are mainly underpinned by small-scale observations, whereas planktonic larvae may be advected over large scales. Using a state-of-the-art sea-ice model we computed Lagrangian back-trajectories to simulate larval krill advection into three distinct recruitment regions and examined modelled sea-ice habitat characteristics along trajectories. From these results we identify potential overwintering habitats and present a conceptual model for explaining regional variability in sea-ice habitat drivers of recruitment. Crucially, many of these sea-ice habitats are currently under-s led. This work can inform future s ling efforts that will improve our understanding of climate change impacts, and potential interactions with the krill fishery.
Location: Australia
No related grants have been discovered for Stuart Corney.