This thesis has used a field based approach to assess the effects of copper liberated from antifouling paints on sessile epifaunal (or fouling) assemblages in southeastern Australia. In the field the effects of dosed copper may be influenced by site conditions, or because the organism has developed tolerance to exposure. To explore these possible effects experiments were conducted inside and outside of two enclosed marinas. Marinas were located at St Kilda (Port Phillip Bay) and Hastings (Western Port Bay), Victoria. At St Kilda, sites were located inside the St Kilda Marina and at St Kilda Pier. At Hastings, sites were located inside Westernport Marina and at Hastings Jetty. Additional sites were also sampled occasionally over the study period. Studies were carried out between 1997-1999. A novel copper dosing system was developed for use in the field. Studies comparing epifaunal assemblages inside and outside the two marinas found that marinas produced different assemblages. The marinas exerted common effects on some functional groups, but effects at the species level differed at each marina. The effects of dosed copper inside and outside the two marinas were tested on: i) the early recruitment of assemblages, and ii) the growth rate and competitive ability of colonial fouling organisms. Results were characterised by high spatial and temporal variability. Copper dose affected a number of species recruiting to the plates but was rarely found to significantly alter growth rates of the colonial organisms; this may be attributed to the high variability observed in growth rates. The competitive ability of colonies was not found to be affected by copper dose or marinas, but few experiments examined this aspect. Reciprocal transplants of settlement plates between sites and copper doses showed that the effect of marinas on assemblages was more important than dosed copper, even though dose levels were well above background concentrations. This is probably due to a large number of factors associated with marinas over and above the effects of increased background heavy metal pollution. Several taxa appeared to adapt to local conditions or copper dose and some appeared to show heterogeneity in response to copper dosing or an ability to acclimate to dose. These types of findings have important implications for the manner in which we apply the findings of traditional laboratory-based ecotoxicology experiments to environmental management.

Disturbance events are thought to provide an opportunity for the colonisation and establishment of invasive species. Contamination of coastal waters with copper from sewage outfall and antifouling paints may create a disturbance that favours the establishment of introduced sessile invertebrates. This study examines if the frequency of experimentally applied doses of copper sulfate increases the abundance of introduced sessile invertebrate species within developing (2-weeks old) and established (9-months old) assemblages. Responses to regular and irregularly applied doses of copper were also tested in developing assemblages. This dataset gives the effects of copper pulse frequency on the number of native and introduced taxa within established (9 month-old) sessile invertebrate assemblages. Experimental manipulations were carried out in Port Phillip Bay at Workshops Jetty, Williamstown, Victoria over a 10 week period between October and December 2004. Nine-month old sessile invertebrate assemblages established on Perspex plates were subjected to three treatments: an undosed control, or copper pulses applied every 2 or 4 weeks.

Disturbance events are thought to provide an opportunity for the colonisation and establishment of invasive species. Contamination of coastal waters with copper from sewage outfall and antifouling paints may create a disturbance that favours the establishment of introduced sessile invertebrates. This study examines if the frequency of experimentally applied doses of copper sulfate increases the abundance of introduced sessile invertebrate species within developing (2-weeks old) and established (9-months old) assemblages. Responses to regular and irregularly applied doses of copper were also tested in developing assemblages. This dataset gives the effects of copper pulse frequency on the number of native and introduced taxa within developing (2-weeks old) sessile invertebrate assemblages. Studies were carried out over 16 weeks between October 2004 and January 2005 at two sites in Port Phillip Bay, Victoria; Workshops Jetty, Williamstown and Point Henry Pier. Workshops Jetty is reported to have higher abundances of sessile invertebrates and is more polluted than Point Henry Pier, providing a comparison between sites with different community assemblages and environment conditions. At Workshops Jetty, four treatments were tested: an undosed control, or copper pulses applied every 4, 3 or 2 weeks. At Point Henry, the same treatments were applied, except for the copper pulse application every 3 weeks. Overall, this study found no evidence to support the hypothesis that disturbance facilitates invasions by introduced species. Disturbance had no effect on the proportion of introduced species and there were no clear differences in the responses on introduced and native species. Whether a species benefited from a disturbance appeared to depend more on its life history characteristics, rather than its point of origin.

Three removal experiments were conducted to test the effects of the introduced species, Bugula neritina, Ascidiella aspersa and Botryllus schlosseri on sessile invertebrate assemblages. Each experiment was run for approximately 2 months between 28th November 2004 and 13th February 2004. These experiments involved removing the introduced species from plates and then comparing these assemblages to those on disturbed control and control plates, where the introduced species had not been removed. The introduced species were removed by scraping them and surrounding species from the surface in 1/8 or 1/4 cm2 areas or by peeling individuals off with forceps. All individuals on the plates were counted and identified at the completion of the experiments.

Study location and species The four species used in this study were collected from subantarctic Macquarie Island (54.6167 degrees S, 158.8500 degrees E), just north of the Antarctic Convergence in the Southern Ocean. Sea temperatures surrounding Macquarie Island are relatively stable throughout the year, with average temperatures ranging from ~4 to 7 degrees C [25]. Collection sites were free from any obvious signs of contamination and did not have elevated concentrations of metals as confirmed by analysis of seawater samples from the collection sites by inductively coupled plasma optical emission spectrometry (ICP-OES; Varian 720-ES). Toxicity tests were conducted at Macquarie Island over the 2013/14 austral summer, and at the Australian Antarctic Division (AAD) in Tasmania, Australia, from 2013 to 2015. The aquarium at the AAD used for culturing and for holding biota prior to their use in tests was maintained at a temperature of 5.8 degrees C under flow-through conditions (at 0.49L/sec). Individuals for toxicity tests on the island and individuals for return to Australia for culturing were collected from a range of habitats within the intertidal and subtidal zones. All species were highly abundant in each of their respective habitats. The gastropod Laevilittorina caliginosa was collected from pools high on the intertidal zone; the flatworm Obrimoposthia ohlini, from the undersides of boulders from the intertidal to shallow subtidal areas; the bivalve Gaimardia trapesina, from several macroalgae species in high energy locations in the shallow subtidal; and the isopod Limnoria stephenseni, from the floating fronds of the kelp Macrocystis pyrifera, which were located several hundred meters offshore. Test specimens were acclimated to laboratory conditions 24 h to 48 h prior to commencement of tests. Juvenile flatworms, isopods and gastropods were all products of reproduction in the laboratory at the AAD, and hence their approximate age at testing is known. The flatworms hatched from small (2 mm in diameter) brown eggs, laid on rocks or on the side of aquaria. The flatworms exhibited age based morphological differences; juvenile flatworms were light grey in colour, while the adults were black. The gastropods hatched from small (1 mm in diameter) translucent eggs laid on weed, often in a cluster. For flatworms and gastropods, juveniles were not all the same age at testing due to differing hatching times, with ages ranging from 2 weeks to 3 months. In contrast, juvenile isopods were all the same age. Although brooding isopods were not observed, juveniles were noticed during routine feeding, thus were likely within 2-3 days of being released, 6 months after adults were brought from the field to the aquarium. The tests with these juvenile isopods were done within 1 week of their being observed. Care was taken to collect adults from the field, for each species, within a narrow size range to minimise differences in ages between individuals tested (Table 1). However, ages of adults individuals used in tests are unknown. The smaller size class of bivalves tested (juveniles: 2.5 plus or minus 0.5 mm, Table 1) was also collected from the field along with the adults (8.0 plus or minus 1.0 mm, Table 1). Based on knowledge on the growth rate of this species (0.8 mm per year; Everson [26], the smaller size class likely represents a young adult of approximately 2.5 to 4 y old, as opposed to a juvenile stage, and adults collected were approximately 9 to 11 y old. Toxicity tests A static non-renewal test regime was used for all tests. Two replicate tests were done for each species at each life stage, with the exception of the juvenile isopods, where due to the limited number of individuals available, only one test was done. Longer tests durations of 14 days were done for acute responses due to the longer life span and response to contaminants compared to temperate and tropical species as determined in previous studies [7, 27]. All experimental

This data collection consists of water quality measurements, nutrient data and measured copper concentrations associated with experiments that derived site-specific guidline values (GVs) for tropical seawater microbiomes by integrating 16S rRNA gene amplicon sequencing with quantitative microbiome profiling and concentration-response modelling. Seawater was collected during high tide at three target sites adjacent to the Burdekin region of the Great Barrier Reef, representing varying disturbance histories: (1) Davies Reef, a high ecological value (HEV) coral reef reference site (S 18°49.826’ E 147°38.177’) situated 50 km offshore with low levels of human impacts and part of the Marine Protected Area; (2) Magnetic Island, a slightly to moderately disturbed (SD-MD) inshore coral/algal reef site (S 19°09.279’ E 146°52.108’) with some perturbations from shipping traffic, dredging, industry, and agricultural runoff; (3) Townsville Breakwater in close proximity to the Port of Townsville, a highly disturbed (HD) inshore site (S 19°14.629’ E 146°49.989’) with increased influence from shipping traffic, industry, and urban runoff. Seawater from each site was subsequently used in a 48-h copper exposure experiment. Water quality measurements (dissolved oxygen, pH and salinity) and water samples for nutrients (dissolved organic / inorganic carbon and nitrogen) were taken at 0-h and 48-h, following standard AIMS procedures. Representative water samples from the nominal experimental treatments (0, 0.1, 0.3, 1, 3, 10, 30, 60, 100, 300, 1000, 3000, 8000 μg Cu L-1) were sent to Envirolab for dissolved copper quantification. Data was entered into excel.