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Assessments of fisheries interactions with non-target species are crucial for quantifying anthropogenic threatening processes and informing management action. We perform the first multi-jurisdictional analysis of spatial and temporal trends, data gaps and risk assessment of cetacean interactions with fisheries gear for the entire Australian Exclusive Economic Zone. Bycatch and entanglement records dating from 1887 to 2016 were collected from across Australia (n = 1987). Since 2000 there has been a substantial increase in reported bycatch and entanglements and this is likely the result of improved monitoring or recording by some jurisdictions and fisheries as well as changing fishing effort, combined with continuing recovery of baleen whale populations after cessation of commercial whaling. A minimum of 27 cetacean species were recorded entangled, with over 30% of records involving interactions with threatened, vulnerable or endangered species. Three times the number of dolphins and toothed whales were recorded entangled compared to baleen whales. Inshore dolphins were assessed as most vulnerable to population decline as a result of entanglements, though humpback whales, common bottlenose dolphins, and short-beaked common dolphins were the most frequently caught. Only one-quarter of animals were reported to have survived entanglement, either through intervention or self-release from fishing gear. Spatial mapping of the records highlighted entanglement hotspots along the east and west coast of the continent, regions where high human population density, high fishing effort, and high density of migrating humpback whales all occur, augmented by high captures of dolphins in shark control gear along the east coast. Areas of few entanglements were more remote, highlighting substantial bias in entanglement reporting. Our gap analysis identified discrepancies in data quality and recording consistency both within and between jurisdictions. Disparities in the types of fisheries data provided for the analysis by different state agencies limited our ability to compile bycatch data in a representative and systematic way. This research highlights the need for improved standardised data recording and reporting by all agencies, and compulsory sharing of detailed fisheries interaction and effort data, as this would increase the value of entanglement and bycatch data as a conservation and management tool. [ABSTRACT FROM AUTHOR]

In-water shark-based tourism is growing worldwide and whale sharks (Rhincodon typus) are one of the most popular targets of this industry. It is important to monitor tourism industries to minimize any potential impacts on target species. At Ningaloo, Western Australia, Electronic Monitoring Systems (EMS) have been installed on licensed tour vessels to collect information on encounters between snorkelers and whale sharks. This study combined data from the EMS with whale shark identification photographs, to assess the impact of in-water tourism on the encounter duration for individual sharks. During 2011 and 2012, 948 encounters with 229 individual sharks were recorded using EMS. Encounter durations between whale sharks and tourism vessels ranged between 1 and 59 min (mean = 11 min 42 s, SD = ±11 min 19 s). We found no evidence for a decline in encounter duration after repeated tourist encounters with individual sharks. Encounter duration varied among tourism operator vessels and were shorter when the sex of the whale shark could not be identified. Given that individual sharks were swum with on average 2.4 times per day (± SD 2.08), and up to 16 times over the course of the study, our results suggest that there is no evidence of long-term impacts of tourism on the whale sharks at Ningaloo. However, the inclusion of well-defined categories of whale shark behaviors and information regarding how interactions between tourists and whale sharks end will complement the data already collected by the EMS. This preliminary investigation demonstrates the potential for the EMS as a data resource to better understand and monitor the impacts of tourism interactions on whale sharks. [ABSTRACT FROM AUTHOR]

In-water shark-based tourism is growing worldwide and whale sharks (Rhincodon typus) are one of the most popular targets of this industry. It is important to monitor tourism industries to minimize any potential impacts on target species. At Ningaloo, Western Australia, Electronic Monitoring Systems (EMS) have been installed on licensed tour vessels to collect information on encounters between snorkelers and whale sharks. This study combined data from the EMS with whale shark identification photographs, to assess the impact of in-water tourism on the encounter duration for individual sharks. During 2011 and 2012, 948 encounters with 229 individual sharks were recorded using EMS. Encounter durations between whale sharks and tourism vessels ranged between 1 and 59 min (mean = 11 min 42 s, SD = ±11 min 19 s). We found no evidence for a decline in encounter duration after repeated tourist encounters with individual sharks. Encounter duration varied among tourism operator vessels and were shorter when the sex of the whale shark could not be identified. Given that individual sharks were swum with on average 2.4 times per day (±SD 2.08), and up to 16 times over the course of the study, our results suggest that there is no evidence of long-term impacts of tourism on the whale sharks at Ningaloo. However, the inclusion of well-defined categories of whale shark behaviors and information regarding how interactions between tourists and whale sharks end will complement the data already collected by the EMS. This preliminary investigation demonstrates the potential for the EMS as a data resource to better understand and monitor the impacts of tourism interactions on whale sharks. [ABSTRACT FROM AUTHOR]

Given limited funding and increasing pressures on our natural resources it is becoming ever more critical that science be directed at improving our understanding and management of priority issues. This relies on dialogue and alignment between researchers and managers to ensure that appropriate questions are asked and the answers incorporated in robust and transparent decision-making processes which should include relevant evidence-based science. We used a prioritisation framework as a tool to bring managers and scientists together to discuss and agree on current priorities for research on marine mammals in Western Australia, including posing relevant questions. Eight species were identified as high priorities for fundamental research, including three dolphin species (Australian humpback, snubfin and common dolphin), three baleen whale species (Antarctic and pygmy blue and dwarf minke whale), the Australian sea lion and the dugong. The pressures we evaluated resulted in a priority need for research to better understand and mitigate impacts across a range of species, including noise pollution from shipping and vessel activity, climate change and fishing by-catch. Scientists and managers agreed on a set of topics and associated research questions for the high-priority species that would best inform ongoing conservation and management of marine mammals in Western Australia and that would have broad applicability nationally and globally. We provide an example of how these priorities can be used to develop a research program with targeted funding. Overall, this process has demonstrated the value of bringing scientists and managers together with a tool that allows them to jointly determine priorities and research questions. [ABSTRACT FROM AUTHOR]

The West Australian Department of Parks and Wildlife (Parks and Wildlife) undertakes and facilitates marine research that informs the management of marine parks and reserves created under the Conservation and Land Management Act 1984 (CALM Act). Broad marine research priorities for management include understanding patterns in the distribution of marine assets and the processes that shape these patterns, improving the design and function of marine reserves, and understanding the ecology of threatened and specially protected marine fauna. More specific and targeted research priorities are required for efficient and effective use of resources. Research relating to the ecological assets listed in each indicative or final marine reserve management plan was prioritised using a framework that considered the ecological and social value of assets, the anthropogenic pressures acting on assets and the current state of knowledge relating to assets. Invertebrates, macroalgae/seagrasses, soft sediment habitat, and intertidal and filter-feeding communities were identified as fundamental research priorities in several marine reserves, whilst the effects of climate change on turtles, coral reef, seagrass, macroalgal and mangrove communities and the effects of fishing on finfish and invertebrate communities were identified as priorities for applied research. A list of >100 marine asset and park specific research strategies is presented, which in combination with fundamental and applied asset priorities identifies focal areas of Parks and Wildlife marine research, promoting efficient use of resources and facilitating collaboration with other research organisations. [ABSTRACT FROM AUTHOR]

This study examined whale shark behaviour using fixed-wing aerial surveys in Ningaloo Marine Park between 2007 and 2009. The aims of the project were to develop and trial a method to test for impacts of tourism vessels and swimmers on whale shark behaviour. Whale sharks made significantly more directional changes when vessels were present, with approximately twice as many changes in direction observed per scan when a vessel was present. Whale sharks also maintained neutral behaviours, such as surface swimming, swimming at depth, resurfacing, or no reaction during interactions and, notably, more of these were recorded when a vessel was present. This suggests that, while behaviours were maintained regardless of the presence of vessels, whale sharks may have still responded to vessels by changing direction more frequently. The aerial observations were effective in detecting an increase in directional changes but further behavioural studies are required to improve our understanding of natural diving and surfacing behaviour in whale sharks. Alternative research platforms and technologies may be necessary to investigate whale shark behaviour in more detail and to further evaluate potential impacts of tourism interactions on whale sharks. [ABSTRACT FROM AUTHOR]

As delphinid populations become increasingly exposed to human activities we rely on our capacity to produce accurate abundance estimates upon which to base management decisions. This study applied mark–recapture methods following the Robust Design to estimate abundance, demographic parameters, and temporary emigration rates of an Indo-Pacific bottlenose dolphin (Tursiops aduncus) population off Bunbury, Western Australia. Boat-based photo-identification surveys were conducted year-round over three consecutive years along pre-determined transect lines to create a consistent sampling effort throughout the study period and area. The best fitting capture–recapture model showed a population with a seasonal Markovian temporary emigration with time varying survival and capture probabilities. Abundance estimates were seasonally dependent with consistently lower numbers obtained during winter and higher during summer and autumn across the three-year study period. Specifically, abundance estimates for all adults and juveniles (combined) varied from a low of 63 (95% CI 59 to 73) in winter of 2007 to a high of 139 (95% CI 134 to148) in autumn of 2009. Temporary emigration rates (γ') for animals absent in the previous period ranged from 0.34 to 0.97 (mean  =  0.54; ±SE 0.11) with a peak during spring. Temporary emigration rates for animals present during the previous period (γ'') were lower, ranging from 0.00 to 0.29, with a mean of 0.16 (± SE 0.04). This model yielded a mean apparent survival estimate for juveniles and adults (combined) of 0.95 (± SE 0.02) and a capture probability from 0.07 to 0.51 with a mean of 0.30 (± SE 0.04). This study demonstrates the importance of incorporating temporary emigration to accurately estimate abundance of coastal delphinids. Temporary emigration rates were high in this study, despite the large area surveyed, indicating the challenges of sampling highly mobile animals which range over large spatial areas. [ABSTRACT FROM AUTHOR]

This study assessed the short-term responses of humpback whales to whale-watching vessels during their southward migration along the south coast of New South Wales (NSW), Australia. The behavior of pods was recorded from commercial whale-watching vessels during tours and compared to pods observed in the absence of vessels from the shore in the same area. While some individuals showed obvious signs of horizontal avoidance, others approached vessels, initiating interactions. Calf pods were more sensitive to the presence of vessels than non-calf pods. Dive times and the overall percentage of time whales spent submerged were higher in the presence of vessels, but respiration intervals did not differ. Some surface behaviors occurred less often in the presence of vessels. Whales' responses differed according to whether vessels were operating in accordance with regulations or not. Whales were more likely to avoid a vessel moving within the permitted 100 m approach limit than vessels outside the limit. Whales showed some behavioral changes when vessels operated in accordance with whale-watching regulations, compared with whales in the absence of vessels. Pods that showed no obvious horizontal responses to vessels changed their diving and surface activity when compared with pods in the absence of vessels. Because the long-term impacts of effects of vessels are unknown, management of the humpback whale-watching industry should adopt a conservative approach. Improved knowledge of long-term impacts of multiple exposures to vessels is required to inform management of the effects of whale-watching. [ABSTRACT FROM AUTHOR]

Focuses on the ethical issues related to the release of animals from captivity. Four reasons for the release of animals; Concerns about animal release programs; Responsibilities of caretakers; Elements of a responsible release project; Selection of candidates for release; Conclusions.

We trialed the collection of blow samples using a waterproof electric multirotor (quadcopter) drone from two free‐ranging dolphin species, the abundant and approachable bottlenose dolphin (Tursiops aduncus) and the less common and boat shy humpback dolphin (Sousa sahulensis). This drone was fast, maneuverable, and quiet compared to other drones commonly used in studies of cetaceans and relative to their hearing thresholds. We were successful in collecting blow samples from four individual dolphins (three bottlenose dolphins and one humpback dolphin) in two groups. The success of obtaining samples was dependent on the individual dolphin's activity. We were successful in sampling when dolphins were resting and socializing but found that socializing dolphins were not predictable in their surfacing and direction and therefore do not recommend drone sampling socializing dolphins. The suitability and preference of the sampling technique over biopsy sampling is highly dependent on the dolphin activity. We also attempted to extract DNA from the blow samples with the aim of assessing the feasibility of using blow sampling by drone for population genetic studies. We were unsuccessful in extracting DNA and recommend that others attempting to sample dolphin blow with a drone should prioritize collecting a larger volume of blow that may yield adequate concentrations of DNA to be amplified. Blow sample volume could potentially be increased by sampling with more absorbent materials. [ABSTRACT FROM AUTHOR]

We report records of humpback dolphins at the Montebello Islands (20°26'S, 115°33′E) approximately 80 km from the mainland coast of Western Australia. This island group is a marine protected area (MPA), with approximately half of the area a sanctuary (no take) zone managed solely for nature conservation that excludes activities such as fishing and resource extraction, activities known to impact dolphins elsewhere. The habitat varies but includes fringing coral reef and shallow, sheltered sandy lagoons mostly < 10 m water depth and not exceeding 20 m. Several opportunistic sightings and one targeted five-day survey have resulted in 28 dolphins being catalogued in the MPA through photo-identification of natural marks on the dorsal fin and are considered to be recognisable through either distinctive or subtle marks. The species was initially reported in the MPA in June 2015 and was present in summer, autumn and winter of 2017. Six calves have been observed in the MPA, with one a neonate. Given the recent listing of the species as Vulnerable on the IUCN Redlist, and increasing pressure on near-shore coastal habitat, recognising the presence of this species at offshore islands such as these, and understanding their status and connectivity is a priority for the conservation and management of the species in Western Australia. [ABSTRACT FROM AUTHOR]