Data was collected from Cockburn Sound to determine: - the past and present distribution of seagrasses; - the 'standing crop' (weight of above-ground material) of seagrass in December 1977; - the light penetration or attenuation in the water column in Cockburn Sound; - the suitability of water quality for seagrass growth through the use of field transplants of seagrass; and - the primary productivity of Posidonia spp. in Cockburn Sound

Two field experiments were carried out on seagrass in the Cockburn Sound area to assess the effect of water quality on seagrass growth. Leaf area was measured before and after transplanting.

Data was collected from Cockburn Sound to determine the past and present distribution of seagrasses, including sediment cores.

A short-term sampling programme in Princess Royal Harbour aimed to compare the mobile macrofauna of a shallow eutrophic seagrass habitat (Posidonia australis) with an adjacent sand habitat. In addition, the mobile macrofauna of an apparently oligotrophic seagrass habitat (Posidonia sinuosa) in King George Sound with an adjacent sand habitat. Species diversity and abundance of fish, macro-crustaceans and molluscs among habitats were also investigated. This sampling was carried out on series of nights between 15th and 25th January 1988.

Mangroves are considered to support rich assemblages of fish and invertebrates. Fishes inhabiting mangrove habitats and at various distances from mangroves across mudflats were sampled to: (1) compare fish assemblages between habitats; and (2) determine the influence of mangrove proximity on fish abundance and diversity in three southern Australian estuaries between November 2005 and January 2006. Based on their distribution, fish species were classified as mangrove residents, mudflat residents, generalists or rare species. The assemblage structure of fish in mangroves differed from assemblages 500m away; however, neither total abundance nor species richness differed significantly between mangroves and mudflats. Mangrove residents and Aldrichetta forsteri (yellow-eyed mullet) displayed strong associations with mangrove habitats, whereas mudflat residents were associated with mudflat habitats. No other fish groups or individual species occurred in higher abundances in either habitat. Total fish abundance, mangrove residents and A. forsteri were positively correlated with pneumatophore density, indicating that the structural complexity of the mangroves might influence the distributions of certain fish species. The current study demonstrated that mangrove habitats in temperate Australia support no greater abundance or diversity of fish than adjacent mudflat habitats and that mangrove proximity does not influence fish distribution at a habitat scale.

The above- and below-ground biomass of three seagrass species, Posidonia australis, Posidonia sinuosa and Amphibolis antarctica, were measured within Princess Royal Harbour. Three sites were used of varying water movement and eutrophication. Sediment samples (to measure grain size and composition) were taken from below seagasses and from adjacent non-vegetated areas for comparsion and productivity measurements were carried out in situ.