Russell William Bradford

The Commonwealth Scientific and Industrial Research Organisation | CSIRO · Oceans & Atmosphere, Hobart, Tasmania

This article is a response to Murua et al.'s Matters Arising article in Nature, "Shark mortality cannot be assessed by fishery overlap alone," which arose from arising from N. Queiroz et al. Nature https://doi.org/10.1038/s41586-019-1444-4 (2019).

Inferences regarding animal presence from passive acoustic receiver arrays are driven by the spatial configuration of receivers. Large, dense arrays provide more information, but maintenance of multiple receivers is costly. Configuring acoustic receiver arrays to maximise coverage while minimising cost is therefore paramount. This study used data f...

In Australian and New Zealand waters, current knowledge on white shark (Carcharodon carcharias) movement ecology is based on individual tracking studies using relatively small numbers of tags. These studies describe a species that occupies highly variable and complex habitats. However, uncertainty remains as to whether the proposed movement pattern...

Large endothermic pelagic sharks are highly migratory and use habitats spanning a broad range of coastal, neritic and oceanic areas. This study aimed to resolve the current lack of information on the movements and habitat use of white sharks, Carcharodon carcharias, between shelf, slope and oceanic areas located off southwestern Australia. Movement...

Management of species with wide-ranging migrations is a complex issue, made more challenging when the species is both protected and poses a risk to humans. Understanding the oceanic conditions associated with shark habitat use can help develop mitigation strategies or warning systems that meet both conservation and human safety objectives. Using sa...

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fle...

The impact of seismic surveys on the catchability of marine fish is a contentious issue, with some claims that seismic surveys may negatively affect catch rates. However little empirical evidence exists to quantify the impacts or identify the mechanisms of such impact. In this study, we used a 2-D seismic survey in the Gippsland Basin, Bass Strait,...

Conservation concerns exist for many sharks but robust estimates of abundance are often lacking. Improving population status is a performance measure for species under conservation or recovery plans, yet the lack of data permitting estimation of population size means the efficacy of management actions can be difficult to assess, and achieving the g...

Estuarine environments are known to provide important feeding, breeding, resting and nursery areas for a range of shark species, including some which are considered dangerous to humans. Juvenile white sharks (<3 m) are known to frequent inshore environments, particularly ocean beaches, but their presence in and use of estuaries and coastal embaymen...

Stereo baited remote underwater video systems (stereo-BRUVs) are commonly used to assess fish assemblages and, more recently, to record the localised abundance and size of sharks. The present study investigated the occurrence and size of white sharks (Carcharodon carcharias) in the near-shore environment off Bennett’s Beach, part of a known nursery...

The seasonal patterns of occurrence of male and female white sharks Carcharodon carcharias at the Neptune Islands in South Australia were reviewed. Analyses of a 14 year data series indicate that females seasonally aggregate in late autumn and winter coinciding with the maximum in-water availability of lactating female long-nose fur seals and seal...

White sharks show a high degree of residency to specific aggregation sites, to which they return regularly over multiple years. Australian research has historically focused on single aggregation areas within each of the southern states where white sharks occur, but other key habitats likely exist and if so, will be important to identify to effectiv...

Identifying essential biological variables in marine ecosystems is harder than essential ocean variables because choices about the latter are guided by the needs of global oceanic models, and the number of candidate variables to choose from is much smaller. We present a process designed to assist managers identify biological indicators and essentia...

The lack of independently verifiable estimates of catches and fisheries independent estimates of abundance and fishing mortality are major sources of uncertainty in the management of many fisheries. DNA profiling provides the potential to substantially improve the quality of data for assessments and act as an additional deterrent to illegal, unrepo...

Estimating the duration of the pelagic phyllosoma phase of the southern rock lobster, Jasus edwardsii (Hutton). Note: This is the "accepted for publication" version. The final published version (http://www.publish.csiro.au/paper/MF14065.htm [doi:10.1071/MF14065]) in Marine and Freshwater Research differs slightly and should be used for citation....

The phyllosoma larva of the southern rock lobster, Jasus edwardsii, is thought to be among the longest larval phases of any planktonic larva, with estimates in the literature ranging from 12 to 24 months. In the present study, we have used an extensive archive of samples (over 2800 samples with 680 phyllosoma) to refine the estimate of the duration...

Juvenile white sharks (Carcharodon carcharias) are recorded along much of the east Australian coast from southern Queensland (QLD) through New South Wales to eastern Victoria as well as northern and eastern Tasmania. White sharks range throughout the Northern Rivers Catchment Management Authority (NRCMA) region spanning north from Crowdy Head to th...

White sharks are a listed threatened species in several regions of the world including the United States, South Africa, Malta, Namibia, New Zealand and Australia, as well as being listed on Appendix II of the Convention for International Trade in Endangered Species (CITES) and under the Convention on Migratory Species (CMS). In Australian waters, w...

This document has been drafted specifically with respect to the capture and tagging of juvenile white sharks for the purpose of attaching satellite tracking tags and/or intra-peritoneal insertion of acoustic tags (via surgery). It details the procedures involved, the identified risks and the control measures in place to minimise those risks. It rec...

Port Lincoln, South Australia is the departure port for the only white shark, Carcharodon carcharias, cage dive industry in Australia. Established in the early 1960's as a niche tourism venture, the industry has recently undergone a rapid expansion to accommodate greater passenger numbers, more tourism operators, and additional infrastructure aimed...

The attraction or provisioning of sharks for the purpose of tourism is a lucrative and popular industry that remains controversial regarding its possible risks to target species and impacts on local ecosystems. The long-term impacts of such activities on the behaviour and movement patterns of sharks have typically been difficult to establish as mos...

1. Search processes play an important role in physical, chemical and biological systems. In animal foraging, the search strategy predators should use to search optimally for prey is an enduring question. Some models demonstrate that when prey is sparsely distributed, an optimal search pattern is a specialised random walk known as a Lévy flight, whe...

Juvenile White Sharks (JWS) in Australian waters appear to occupy different coastal habitats during their early years. Two juvenile nursery areas are known in southeastern Australia, each with different resident periods. Juveniles are seasonally resident in the Port Stephens region of central New South Wales from mid-August to early January. Sharks...

The movements and behavior of 22 juvenile White Sharks, Carcharodon carcharias [1.75–2.6 m total length (TL)], were monitored in eastern Australia using satellite tracking and pop-up archival tags, providing a total of 1,941 d of data. Broad-scale movements were primarily coastal, were highly directional with high angular concentration values r (me...

Passive acoustic monitoring has become a common tool for monitoring tagged marine animals. Recent improvements in acoustic technology have addressed some of the limitations of the system; specifically, the need to manually download data and the time delay between detection and data analysis. Coupling a robust passive acoustic receiver with a satell...

Satellite telemetry was used to study the movements and behaviour of ten blue sharks and one individual each of shortfin mako, thresher and bigeye thresher off eastern Australia. The tracks showed latitudinal movements of up to 1,900km, but none of the sharks travelled away from the eastern Australian region. Tracking periods did not exceed 177days...

Recent advances in electronic tag technology have resulted in an explosion of data for marine biologists. Providing descriptions of data management systems and discussion of their strengths and weaknesses will be important in promoting a dialogue with the ultimate goal of building better systems to support research. The importance of this will only...

Finale Report to the Fisheries Research and Development Corporation. [http://frdc.com.au/research/Documents/Final_reports/2002-007-DLD.PDF]

The rock lobster Jasus edwardsii forms the basis of important fisheries in south‐eastern Australia and New Zealand. Their long pelagic larval phyllosoma phase (12–24 months) raises many questions as to how the larvae are retained and/or recruited into local populations. Recent attempts to model the dispersal of J. edwardsii phyllosoma have had mixe...

Final report to the Australian Government Department of the Environment and Heritage.

Final Report tot he Australian Government Department of the Environment and Heritage

Final Report to the Australian Government Department of the Environment and Heritage

In May 1996 the biological oceanography of the main yellowfin tuna longline fishing waters off southern New South Wales, Australia, was examined in relation to the catch by the fishery. A warm-core eddy was identified directly east of Eden with a temperature at 250 m depth of 15°C. At the western edge of this eddy, relatively high levels of fluores...

The early life histories of the commercially important blue and spotted warehous (Seriolella brama and S. punctata) were examined on the basis of archived ichthyoplankton samples collected over broad areas of southern Australia. Larvae of both species were widely distributed during winter and spring within shelf and slope waters. Larvae of S. brama...

The biomass, abundance, species diversity and length-frequency distribution of macrozooplankton and micronekton at a deep-ocean dumpsite southeast of Tasmania, Australia, were compared with those of the surrounding water masses. The dumping of jarosite – a waste product of zinc refining that contains trace quantities of heavy metals – began in 1973...

The diets of 1219 southern bluefin tuna, Thunnus maccoyii, from inshore (shelf) and offshore (oceanic) waters off eastern Tasmania were examined between 1992 and 1994. Immature fish (< 155 cm fork length) made up 88% of those examined. In all, 92 prey taxa were identified. Inshore, the main prey were fish (Trachurus declivis and Emmelichthys nitidu...

An unprecedented mass mortality of pilchard, Sardinops sagax, occurred in Australia in 1995, spreading east and west from the Great Australian Bight at approximately 0á5 m s-1 and 0·3 m s-1 respectively to span the 6000-km range of the species from Noosa, Queensland, to Geraldton, Western Australia. Mortalities with the same clinical signs of hypox...

The southern bluefin tuna (SBT) supports a seasonal fishery off the east coast of Tasmania, Australia. The distribution of zooplankton biomass in this region was examined as a means of finding out why the SBT are attracted to this area. We examined whether there was a particular area or depth stratum that supported significantly greater amounts of...

Midwater fishes were sampled at night to a depth of 400 m in oceanic waters east of Tasmania, Australia, in May/June of 1992, 1993 and 1994. We examined whether there were differences in the distribution and density of these fishes in relation to the subtropical convergence (STC) separating East Australia Current (EAC) water from subantarctic water...