This thesis was conducted under the auspices of the Southern Ocean Continuous Plankton Recorder (CPR) Survey. The research conducted had the dual aims of providing baseline data for this long-term monitoring program and providing the first detailed analysis of zooplankton communities and distribution patterns in the Southern Ocean south of Australia. Data were principally collected between October 2001 and March 2002, during five voyages. As a primary step I investigated the sampling characteristics of CPR, and assessed the utility of the CPR as a long-term monitoring apparatus in the Southern Ocean. Given the shallow sampling depth of the CPR (~10.5m), a major requirement of this calibration was quantification of the fine-scale vertical distributions zooplankton. This was done through direct comparison of CPR samples with depth integrated NORPAC net hauls. The CPR-NORPAC comparison identified the component of the zooplankton sampled by the CPR and provided a means for comparison between past and present data sets. As a final component of this calibration, it was demonstrated that the CPR was effective at identifying biogeographic boundaries. An essential requirement for the identification of long-term ecological change is baseline data on natural ecosystem variability, particularly seasonality. Therefore, after calibration of the CPR the two fundamental components of spatial and seasonal variability were investigated. Firstly, the fine-scale horizontal structure of zooplankton communities was quantified from a 1170 nautical mile transect, along the 140oE meridian, spanning all of the major oceanographic zones south of Australia. Applying multivariate analyses a unique community zonation was identified which was strongly related to the complex oceanographic environment, characterised by multiple branches of the major fronts. The seasonal component of temporal variability was investigated separately in two major and distinctly different regions, the Seasonal Ice Zone and the Sub-Antarctic / Polar Frontal Zone. Multivariate analyses were used to quantify seasonal changes in species composition, Bray-Curtis dissimilarity, species densities, and the proportional contribution of species to communities. The spatial and temporal variation of zooplankton community structure was discussed in the light of environmental controls, species' vertical distributions, population cycles, and ecosystem functioning. Finally,the application of these data to long-term monitoring was discussed, and recommendations made for future research. The fields in this dataset are: CPR Segment Number Time (GMT) Date Latitude Longitude Segment Length (nautical miles) Salinity Sea Surface Temperature Species Fish Larvae Fish Scales Egg Mass Volume Bongo CTD Depth

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 13/10/2005. 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.

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 05/04/2005. 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.

Mesozooplankton community composition and structure were examined throughout the D’Entrecasteaux Channel, Huon Estuary and North West Bay, Tasmania. The data represented by this record was collected as part of a grazing study conducted in Hideaway Bay, Huon Estuary (20-21 September, 2005). The grazing impacts of microzooplankton and mesoplankton on the phytoplankton communities were examined during several process studies. Experiments with mesozooplankton grazers were restricted to dominant omnivorous copepods (e.g. Acartia tranteri, Paracalanus indicus, Centropages australiensis) cladocerans and appendicularians. Grazing rates of microzooplankton reached as high as 96% of daily primary production, while that of mesozooplankton herbivours was never greater than 20%. Trophic interactions between the species are complicated by the recent arrival of the heterotrophic dinoflagellate Noctiluca scintillans to the region. This species grazes heavily on phytoplankton, smaller zooplankton and faecal pellets. Noctiluca scintillans accounted for up to 20% of mesozooplankton abundance in autumn and it is capable of both suppressing zooplankton abundance and reducing the sedimentation of faecal pellets to the seafloor.

Many studies compare utilization of different marine habitats by fish and decapod crustaceans; few compare multiple vegetated habitats, especially using the same sampling equipment. Fish and invertebrates in seagrass, mangrove, saltmarsh, and nonvegetated habitats were sampled during May–August (Austral winter) and December–January (Austral summer) in the Barker Inlet-Port River estuary, South Australia. Sampling was undertaken using pop nets in all habitats and seine nets in seagrass and nonvegetated areas. A total of 7,895 fish and invertebrates spanning 3 classes, 9 orders, and at least 23 families were collected. Only one fish species, Atherinosoma microstoma, was collected in all 4 habitats, 11 species were found in 3 habitats (mangroves, seagrass, and nonvegetated), and 13 species were only caught in seagrass and nonvegetated habitats. Seagrass generally supported the highest numbers of fish and invertebrates and had the greatest species richness. Saltmarsh was at the other extreme with 29 individuals caught from two species. Mangroves and nonvegetated habitats generally had more fish, invertebrates, and species than saltmarsh, but less than seagrass. Analyses of abundances of individual species generally showed an interaction between habitat and month indicating that the same patterns were not found through time in all habitats. All habitats supported distinct assemblages although seagrass and nonvegetated assemblages were similar in some months. The generality of these patterns requires further investigation at other estuaries. Loss of vegetated habitats, particularly seagrass, could result in loss of species richness and abundance, especially for organisms that were not found in other habitats. Although low abundances were found in saltmarsh and mangroves, species may use these habitats for varying reasons, such as spawning, and such use should not be ignored.

Shelf-wide Research Vessel Surveys are conducted 4-8 times per year over the continental shelf from Cape Hatteras, North Carolina to Cape Sable, Nova Scotia, using NOAA research ships or charter vessels. The Cape Hatteras to Cape Sable area is divided into four regions, and 30 randomly selected stations are targeted for sampling from each region. The investigation utilizes shelf-wide research vessel surveys to gather data on planktonic organisms including zooplankton and ichtyoplankton. Environmental parameters are also collected but stored in different databases (e.g., OCDBS). The investigation monitors the fishery-relevant components of the Northeast Shelf ecosystem, to characterize the baseline conditions and to determine the effects of biological and physical processes on the recruitment of Northeast shelf fishes.

In February and June 1983, fishes and benthic fauna were sampled to provide quantitative estimates of densities and volumes of the benthic invertebrate animals and biomass of the seagrass in summer, as well as abundances of the fishes occurring during the day and night and in both summer and winter in Amphibolis seagrass beds and sand flats at Monkey Mia Shark Bay, Western Australia.

The data is quantitative abundance of fish and megafaunal invertebrates and algal % cover derived from transect based counts at a wide range of locations across Temperate Australia. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. Methods were initially developed for research on temporal changes following protection in Tasmanian MPAs (Maria Is, Tinderbox, Ninepin Point, Governor Island). The data represented by this record was collected in MPA studies and surveys interstate, and was collected from Batemans Bay (NSW). In many cases the dataset involved temporal replication (year scale).