Andrea Walters

Institute for Marine and Antarctic Studies, University of Tasmania (Australia)

Introduction Mesopelagic fishes play a central role in the transfer of energy through open-ocean food webs, particularly in the Southern Ocean where they are both important predators of zooplankton and a key prey group for many higher predators. However, they are notoriously difficult to sample, which has limited our understanding of the bio-physic...

The global importance of mesopelagic fish is increasingly recognised, but they remain poorly studied. This is particularly true in the Southern Ocean, where mesopelagic fishes are both key predators and prey, but where the remote environment makes sampling challenging. Despite this, multiple national Antarctic research programs have undertaken regi...

Cephalopods are an important component of Southern Ocean food webs, but aspects of their trophic ecology remain unresolved. Here, we used archived squid (order Teuthida) beaks, collected from stomach contents of predators at Macquarie and Kerguelen Islands, to investigate the trophic structure within an assemblage of pelagic squids ( Alluroteuthis...

Southern Ocean ecosystems are globally important and vulnerable to global drivers of change, yet they remain challenging to study. Fish and squid make up a significant portion of the biomass within the Southern Ocean, filling key roles in food webs from forage to mid-trophic species and top predators. They comprise a diverse array of species unique...

Quantification of the physical and biological factors that influence the spatial structuring of food webs is central to inform effective resource management. We used baseline‐corrected stable isotope ratios (δ13C and δ15N) of 63 invertebrate and fish to investigate food web structure across a continental shelf gradient—the Celtic Sea Shelf in the N...

The large-scale spatial patterns and primary drivers of food web dynamics across seascapes can be investigated using isotope ratios in marine consumers. However, interpreting complex signatures from mobile animals can require good knowledge of spatial isotopic variations in the environment. This is particularly true in the Southern Ocean where regi...

Large submarine plateaus impede the eastward flow of the deep‐reaching Antarctic Circumpolar Current (ACC), and at the southern Kerguelen Plateau (SKP), the ACC flow is steered north through the Fawn Trough and south through the Princess Elizabeth Trough. During the Kerguelen Axis study, a regional‐scale ecosystem survey, oceanographic sampling sho...

Antarctic lanternfish (Electrona antarctica) is the dominant mesopelagic fish species in the Southern Ocean. It is the most common myctophid occurring south of the Antarctic Polar Front, and an important component of Southern Ocean food webs, both as a zooplankton predator and as a major prey item for higher predators. Despite its importance, there...

Mesopelagic fish are an important but poorly understood mid-trophic component of pelagic food webs. There are major uncertainties regarding their trophodynamics and their overall contribution to the broader Southern Ocean food web. This study aimed to investigate the trophic role of mesopelagic fish in the region of the southern Kerguelen Plateau,...

Mesopelagic fish represent an important trophic link between zooplankton and higher order predators in Southern Ocean food webs. Information on their feeding habits is still sparse, representing a key area of uncertainty in efforts to understand and model Southern Ocean food web dynamics. We used visual assessment of stomach contents to characteris...

Pelagic squids are a key component in Southern Ocean ecosystems. Most species have a circumpolar distribution that is patchy in relation to major oceanographic features. However, little is known regarding where and when they spawn, or subsequently, what environmental predictors drive the size distribution particularly during early life stages. Here...

Mesopelagic fish form an important link between zooplankton and higher trophic levels in Southern Ocean food webs, however their diets are poorly known. Most of the dietary information available comes from morphological analysis of stomach contents and to a lesser extent fatty acid and stable isotopes. DNA sequencing could substantially improve our...

Development in foraging behaviour and dietary intake of many vertebrates are age-structured. Differences in feeding ecology may correlate with ontogenetic shifts in dispersal patterns, and therefore affect foraging habitat and resource utilization. Such life-history traits have important implications in interpreting tropho-dynamic linkages. Stable...