Mesozooplankton community composition and structure were examined throughout the D’Entrecasteaux Channel, Huon Estuary and North West Bay, Tasmania, from November 2004 to October 2005, the data represented by this record was collected on the 06/09/2005. The composition of the mesozooplankton community was typical of inshore, temperate marine habitats, with seasonally higher abundance in summer and autumn and lower numbers in winter and spring. Copepods were the largest contributors to total abundance across all seasons and stations, while cladocerans and appendicularians were proportionally abundant in spring and summer. The faecal pellets of these three main groups, along with those of krill and amphipods, also contributed significantly to material recovered from sediment traps. Meroplanktonic larvae of benthic animals showed short-term peaks in abundance and were often absent from the water column for long periods. Spatially, North West Bay and the Channel had a higher representation of typically marine species, including Calanus australis and Labidocera cervi, while truly estuarine species, such as the copepod Gladioferens pectinatus, were more important in the Huon Estuary.

Sea urchins have the capacity to destructively overgraze kelp beds and cause a wholesale shift to an alternative and stable ‘urchin barren’ state. However, their destructive grazing behaviour can be highly labile and contingent on behavioural shifts at the individual and local population level. Changes in supply of allochthonous food sources, i.e. availability of drift-kelp, is often suggested as a proximate trigger of change in sea urchin grazing behaviour, yet field tests of this hypothesis are rare. Here we conduct a suite of in situ behavioural surveys and manipulative experiments within kelp beds and on urchin barrens to examine foraging movements and evidence for a behavioural switch to an overgrazing mode by the Australian sea urchin Heliocidaris erythrogramma (Echinometridae). Tracking of urchins using time-lapse photography revealed urchin foraging to broadly conform to a random-walk-model within both kelp beds and on barren grounds, while at the individual level there was a tendency towards local ‘homing’ to proximate crevices. However, consistent with locally observed ‘mobile feeding fronts’ that can develop at the barrens-kelp interface, urchins were experimentally inducible to show directional movement toward newly available kelp. Furthermore, field assays revealed urchin grazing rates to be high on both simulated drift-kelp and attached kelp thalli on barren grounds, however drift-kelp but not attached kelp was consumed at high rates within kelp beds. Time-lapse tracking of urchin foraging before/ after the controlled addition of drift-kelp on barrens revealed a reduction in foraging movement across the reef surface when drift-kelp was captured. Collectively results indicate that the availability of drift-kelp is a pivotal trigger in determining urchin feeding modes, which is demonstrably passive and cryptic in the presence of a ready supply of drift-kelp. Recovery of kelp beds therefore appears possible if a sustained influx of drift-kelp was to inundate urchin barrens, particularly on reefs where local urchin densities and where grazing pressure is close to the threshold enabling kelp bed recovery.

Limited SCUBA surveys of weedy seadragons at Kingston, Blackman's Bay & Bicheno and spiny pipehorses at Simpson's Point, Bruny Island. Mark-recapture study of approximately 40 seadragons and 10 spiny pipehorses.

Describes the database used for storing Southern Rock Lobster (Jasus edwardsii) biological data collected by observers on commercial boats and dedicated research trips incorporating information on sex, length, weight, damage, reproduction, bycatch, protected species interaction, location, depth, tagging and equipment type.

Utilising both fishery independent and industry dependent surveys, spatial and temporal data was collected on scallop, and other bethnic community, abundance.

The threatened status of shellfish reefs has been well established globally (e.g Beck et al 2011) however the ecological consequences of these losses is still largely unknown. In Australia, shellfish reefs are one of the most imperilled marine habitat types (Gillies et al 2018), due to historical overharvest and widespread eutrophication of coastal waters through the use of fertilizers, livestock and human waste. Marine bivalves are important ecosystem engineers providing habitat, shelter and a food source for other species in benthic soft-sediment environments. In addition, filter-feeding bivalves link benthic and pelagic components of ecosystems through filtration and excretion. Through their filter feeding, they produce large amounts of faeces (digested seston) and pseudofaeces (rejected particles bound up in mucus) which are deposited on the benthos. This process brings energy and nutrients from the pelagic system to the benthic system (bentho-pelagic coupling). The removal of large quantities of seston can serve an important ecosystem function by improving water quality and clarity. The filtration of water performed by bivalves has been demonstrated to reduce water turbidity, improving light penetration and thereby enhancing growing conditions for seagrasses (Wall et al 2008). In systems where healthy populations of bivalves remain, they can filter a volume equivalent or larger than the entire estuary volume within the residence time of the water (zu Ermgassen et al 2013). While such densities of oysters are rare today, this highlights the critical ecosystem services that are lost when oyster reefs decline. Furthermore, it demonstrates the potential functions that can be regained through oyster reef restoration. Given the increasing awareness of the decline of these ecosystems, interest in restoration efforts to restore critical ecosystem functions has been growing. However, conservation and restoration decision making is underpinned by reliable quantification of relevant ecosystem services (zu Ermgassen et al 2016). For example, there are plans to restore some of the natural oyster reefs of Sydney Rock Oyster (Saccostrea glomerata) in Port Stephens, New South Wales. One of the main drivers motivating this restoration project is restoring lost ecosystem services. The filtration rates of Australian oysters has been demonstrated in aquarium studies using filtered water augmented with algae, yet little is known about filtration and biodeposition rates of oysters using raw seawater. In this study, we provide the first evaluation of the filtration and biodeposition rate of four species of bivalves using raw seawater, providing a proxy for natural biodeposition rates. As such, this study provides a first indication of the filtration/nutrient cycling function that may be restored following oyster restoration efforts.

This projects' data on abalone translocations is stored in two databases containing data collected for abalone aggregation and larval surveys in Tasmania. Genetic information has also been generated using microsatellites.

Invasive mammal eradications are commonplace in island conservation. However, post-eradication monitoring beyond the confirmation of target species removal is rarer. Seabirds are ecosystem engineers on islands and are negatively affected by invasive mammals. Following an invasive mammal eradication, the recovery of seabird populations can be necessary for wider ecosystem recovery. Seabirds fertilise islands with isotopically heavy nitrogen, which means nitrogen stable isotope analysis (δ15N) could provide a useful means for assessing corresponding change in ecosystem function. We quantified decadal changes in δ15N on eight temperate New Zealand islands subject in pairs to distinct mammal invasion and seabird restoration histories: invaded, never-invaded, invader-eradicated and undergoing active seabird restoration. First, we investigated long-term changes in δ15N values on individual islands. Second, we used a space for time analysis to determine if δ15N levels on islands from which invaders had been removed eventually recovered to values typical of never-invaded islands. On each island soil, plants (Coprosma repens, C. robust and Myrsine australis) and spiders (Porrhothelidae) were sampled in 2006/07 and 2022 allowing δ15N change on individual islands over 16 years to be assessed. Combined, the samples from invader-eradicated islands provided a 7 – 32 year post-eradication dataset. Change in δ15N was only detected on one island across the study period, following the unexpected recolonisation of seabirds to an invaded island. Invader-eradicated islands generally had higher δ15N values than invaded islands however, they were still lower than never-invaded islands and there was no trend in δ15N with time since eradication. This, and the measurable increase in δ15N following seabird recolonisation on one island, may suggest that δ15N change occurs rapidly following invader-eradication, but then slows, with δ15N values staying relatively constant in the time period studied here. Isotope and seabird population studies need to be coupled to ascertain if plateauing in δ15N reflects a slowing of seabird population growth and subsequent basal nutrient input, or if the baseline nutrients are entering the ecosystem but then not propagating up the food web.