Coastal state fisheries management : a review of Australian enforcement action in the Heard and McDonald Islands Australian Fishing Zone

In 1953 the Heard and McDonald Islands Act, which formalised the transfer of sovereignty over the two named sub-Antarctic islands from the United Kingdom, was passed by the Australian Government. For the ensuing 40 years, Australian management of the Islands was uneventful. The first subAntarctic scientific station was established at Atlas Cove, on Heard Island, in December 1947 following the initial indication by Britain of a willingness to transfer rights to the Islands. In 1987 the Islands, together with their 12 mile territorial sea, were proclaimed a wilderness reserve with a number of activities including fishing and mining prohibited. The same area was included on the WorId Heritage List in 1997. In 1979 a 200 nautical mile Australian Fishing Zone (AFZ) was proclaimed around all Australian territories. In 1994 new terminology was embraced and the Exclusive Economic Zone was declared.

Bad habits and prosthetic performances : negotiation of individuality and embodiment of social status in Australian shark fishing

Anthropological discussion of individuality, as a component of masculinity, has tended to focus on either the performance and championing of autonomy in the West (e.g., Kapferer) or the manner in which people in non-Western contexts become explicitly manifest through relationships with others (e.g., Strathern). In this paper, I consider an atypical example of masculine identity by describing intimate interpersonal relationships between Australian commercial shark boat skippers and their young deckhands. As in other Western fisheries (e.g., Icelandic), economic success and physical safety are promoted through synergism among fishers. In the Australian case, however, the degree of corporeal cooperation is so extreme that deckhands resemble living prostheses of their skipper, embodying their peripheral socio-productive status. I consider this bond in the context of the Australian ethos of masculinity, in which displays of "individuality" are key. However, for young deckhands, their prosthetic role can compromise their passage into manhood.

Deep identity, shallow time : sustaining a future in Victorian fishing communities

Like commercial fishers everywhere, it seems, those living in coastal communities of Victoria perceive themselves to be under threat from recreational fishers, environmentalists, imposed management regimes, and modernisation and globalisation of the industry. In responding to these threats they appeal to conventional props of tradition--to continuity in genealogical time, affiliation with place and specialised knowledge and practice. This seems paradoxical, given that most established fishers in Victoria are first or second generation members of an industry that, through its 150-year history, has been characterised by innovation and mobility. That paradox, we argue, is more apparent than real. Fisher identity is grounded primarily in engagement with an environment that is not familiar to outsiders. The paradox arises because fishers, like others who seek to sustain a future in the face of threat from outsiders, reshape strongly felt identity as tradition.

Trophic effects of fishing southern rock lobster Jasus edwardsii shown by combined fatty acid and stable isotope analyses

The southern rock lobster Jasus edwardsii is a commercial species that has benefited from the complete protection offered by no-take reserves, with higher abundances and larger animals recorded in reserves than in adjacent fished areas. What remains unclear is whether there is any change in the diet of lobsters in reserves, for example, as a result of increased intraspecific competition for food. We used combined chemical tracers to examine the diet of lobsters in fished and reserve areas in 2 bioregions in eastern Tasmania. δ15N values of lobsters were richer in fished than in reserve areas, indicating that lobsters eat a greater proportion of food items from higher trophic levels in fished areas. Mixing models suggest that ascidians, sea urchins and the turbinid gastropod were all important food sources for lobsters, but the importance of these food items differed between bioregions. This spatial variability may suggest that the small size of the reserve in one bioregion is inadequate at ensuring the diet of lobsters is protected from fishing pressure. Fatty acid profiles of lobsters supported the importance of these food sources to lobsters. Differences between bioregions, or inside and outside of reserves, were not apparent using fatty acids. The present study highlights that lobster fishing has the capacity to alter the trophic status of prey for generalist predators and suggests that fatty acid analyses may be limited in detecting changes in the dietary composition of such generalist feeders.

Changes in catch rates and length and age at maturity, but not growth, of an estuarine plotosid (cnidoglanis macrocephalus) after heavy fishing

The hypothesis that heavy fishing pressure has led to changes in the biological characteristics of the estuary cobbler (Cnidoglanis macrocephalus) was tested in a large seasonally open estuary in southwestern Australia, where this species completes its life cycle and is the most valuable commercial fish species. Comparisons were made between seasonal data collected for this plotosid (eeltail catfish) in Wilson Inlet during 2005-08 and those recorded with the same fishery-independent sampling regime during 1987-89. These comparisons show that the proportions of larger and older individuals and the catch rates in the more recent period were far lower, i.e., they constituted reductions of 40% for fish ≥430 mm total length, 62% for fish ≥4 years of age, and 80% for catch rate. In addition, total mortality and fishing-induced mortality estimates increased by factors of ~2 and 2.5, respectively. The indications that the abundance and proportion of older C. macrocephalus declined between the two periods are consistent with the perception of long-term commercial fishermen and their shift toward using a smaller maximum gill net mesh to target this species. The sustained heavy fishing pressure on C. macrocephalus between 1987-89 and 2005-08 was accompanied by a marked reduction in length and age at maturity of this species. The shift in probabilistic maturation reaction norms toward smaller fish in 2005-08 and the lack of a conspicuous change in growth between the two periods indicate that the maturity changes were related to fishery-induced evolution rather than to compensatory responses to reduced fish densities.

Recreational value of Southern Bluefin Tuna fishing

Southern bluefin tuna (Thunnus Maccoyii) is a global resource, which is critically endangered. The Committee for the Conservation of Southern Bluefin Tuna sets commercial quota levels for member nations, including Australia, each year. However, southern bluefin tuna is also a popular “trophy” fish with recreational anglers. The size of the total recreational catch, which is not included in the quota, is unknown but thought to be significant. This paper reports the findings of a study designed to estimate the recreational value of the non-commercial southern bluefin tuna catch at Portland, in southwest Victoria. The results indicate that the size of the recreational catch at Portland is considerable and therefore significant in terms of the management of the fishery. Furthermore, the non-market recreational values associated with the fishery are substantial with the on-site recreational use value (consumer surplus) per person per visit estimated to be between $33 and $132 and the on-site annual recreational use value of the fishery for one season is estimated to be between $449,533 and $1,325,124.

Satellite telemetry suggests high levels of fishing-induced mortality in marine turtles

Long-term records of nesting numbers, or proxies to nesting numbers, show a precipitous decline in the size of many sea turtle populations. Population declines are most frequently attributed to fisheries bycatch, although direct quantification of this level of mortality is rare. We used satellite-tracking records for turtles in the Mediterranean Sea and Pacific, Atlantic and Indian Oceans to identify when turtles had been captured. Evidence for capture came from a combination of an increase in good quality locations from transmitters, transmitters moving inland to coastal towns and villages, and on-board submergence data, showing that transmitters had come out of the water. A high level of mortality was calculated, confirming current concerns regarding the outlook for sea turtles.

Spatial patterns, landscape genetics and post virus recovery of blacklip abalone, Haliotis rubra (Leach), in the western commercial fishing zone of Victoria

Historically, collecting nearshore habitat information has been problematic. Existing methods, such as aerial and satellite image interpretation are limited due to the attenuation of light in the water column obscuring the seabed structure. The advent of airborne bathymetric LiDAR (Light Detection and Ranging) systems (laser scanning of the seabed) now provides high-resolution seabed ‘images’ in areas that were previously difficult to survey. LiDAR imagery is available for the entire coastline of Victoria, Australia to depths of around 25 m, after being initially collected for climate change modelling by the Future Coasts Program (http://www.climatechange.vic.gov.au/adapting-to-climate-change/future-coasts). This dataset has provided the opportunity to test its applicability to inform fisheries management. Detailed geophysical information combined with spatially explicit AbTrack GPS located fisheries records and targeted genetic sampling is used in this study to provide a better understanding of the extent of available fishing grounds, direction of fishing effort and stock population structure within the Victorian western zone abalone fishery.
The species distribution modelling technique MaxEnt was used to produce a potential habitat suitability map for abalone in an attempt to capture the effective footprint of the  fishery. Also, by interrogating the spatially defined effort localities, we demonstrate an approach that may be used to identify areas where fishing effort is concentrated, and how this parameter changes temporally.
Despite barriers to adult dispersal (soft sediment barriers between reef patches), the genetic study indicates that larval movement is able to homogenize the gene pool over  large geographic distances. The western, central and eastern zone abalone stocks in Victoria were found to be a single large panmictic unit. This indicates high levels of stock connectivity and no obvious impacts of Abalone Viral Ganglioneuritis (AVG) on the genetic health of western zone stocks. We used detailed seafloor structure information interpreted from LiDAR to inform a replicated hierarchical fine scale genetic sampling design. We demonstrated that there may be extensive migration among abalone stocks across the Victorian abalone fishery.
This is contrary to previous studies that suggest recruitment is highly localised. In combination, these findings provide a valuable insight into the biology of H. rubra and immediate benefits for fisheries management. We discuss these results in the context of predicting resilience and adaptive potential of H. rubra stocks to environmental pressures and the spread of heritable diseases.
Adoption pathways are also provided to benefit future stock augmentation activities to catalyse the recovery of AVG affected reef codes. As larval dispersal is likely to be spatially and temporally variable, some AVG affected stocks are likely to recover through natural recruitment, while others will benefit from augmentation activities to ‘kick-start’ stock recovery. Evidence of neutral genetic homogeneity across Victorian reef codes suggests that the relocation of animals is unlikely to have significant genetic risks; however the potential for locally adaptive genetic differences may exist, and should be taken into consideration in future stock augmentation planning.
When combined, the spatial and genetic analyses provide valuable insights into stock productivity within the western zone fishery. Reefs appear to be expansive and support much available habitat, and the movement of larvae among reef structures is likely to be extensive in this region. Consequently, we propose that colonisation success and productivity is likely to be driven by ecological factors such as resources and/or competition, or physical factors such as wave exposure.

Exploring spatiotemporal trends in commercial fishing effort of an abalone fishing zone: a GIS-based hotspot model

Assessing patterns of fisheries activity at a scale related to resource exploitation has received particular attention in recent times. However, acquiring data about the distribution and spatiotemporal allocation of catch and fishing effort in small scale benthic fisheries remains challenging. Here, we used GIS-based spatio-statistical models to investigate the footprint of commercial diving events on blacklip abalone (Haliotis rubra) stocks along the south-west coast of Victoria, Australia from 2008 to 2011. Using abalone catch data matched with GPS location we found catch per unit of fishing effort (CPUE) was not uniformly spatially and temporally distributed across the study area. Spatial autocorrelation and hotspot analysis revealed significant spatiotemporal clusters of CPUE (with distance thresholds of 100's of meters) among years, indicating the presence of CPUE hotspots focused on specific reefs. Cumulative hotspot maps indicated that certain reef complexes were consistently targeted across years but with varying intensity, however often a relatively small proportion of the full reef extent was targeted. Integrating CPUE with remotely-sensed light detection and ranging (LiDAR) derived bathymetry data using generalized additive mixed model corroborated that fishing pressure primarily coincided with shallow, rugose and complex components of reef structures. This study demonstrates that a geospatial approach is efficient in detecting patterns and trends in commercial fishing effort and its association with seafloor characteristics.

Predictive mapping of abalone fishing grounds using remotely-sensed LiDAR and commercial catch data

Defining the geographic extent of suitable fishing grounds at a scale relevant to resource exploitation for commercial benthic species can be problematic. Bathymetric light detection and ranging (LiDAR) systems provide an opportunity to enhance ecosystem-based fisheries management strategies for coastally distributed benthic fisheries. In this study we define the spatial extent of suitable fishing grounds for the blacklip abalone (Haliotis rubra) along 200 linear kilometers of coastal waters for the first time, demonstrating the potential for integration of remotely-sensed data with commercial catch information. Variables representing seafloor structure, generated from airborne bathymetric LiDAR were combined with spatially-explicit fishing event data, to characterize the geographic footprint of the western Victorian abalone fishery, in south-east Australia. A MaxEnt modeling approach determined that bathymetry, rugosity and complexity were the three most important predictors in defining suitable fishing grounds (AUC = 0.89). Suitable fishing grounds predicted by the model showed a good relationship with catch statistics within each sub-zone of the fishery, suggesting that model outputs may be a useful surrogate for potential catch.