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Understanding species’ distribution patterns and the environmental and ecological interactions that drive them is fundamental for biodiversity conservation. Data deficiency exists in areas that are difficult to access, or where resources are limited. We use a broad-scale, non-targeted dataset to describe dolphin distribution and habitat suitability in remote north Western Australia, where there is a paucity of data to adequately inform species management. From 1,169 opportunistic dolphin sightings obtained from 10 dugong aerial surveys conducted over a four-year period, there were 661 Indo-Pacific bottlenose dolphin (Tursiops aduncus), 191 Australian humpback dolphin (Sousa sahulensis), nine Australian snubfin dolphin (Orcaella heinsohni), 16 Stenella sp., one killer whale (Orcinus orca), one false killer whale (Pseudorca crassidens), and 290 unidentified dolphin species sightings. Maximum Entropy (MaxEnt) habitat suitability models identified shallow intertidal areas around mainland coast, islands and shoals as important areas for humpback dolphins. In contrast, bottlenose dolphins are more likely to occur further offshore and at greater depths, suggesting niche partitioning between these two sympatric species. Bottlenose dolphin response to sea surface temperature is markedly different between seasons (positive in May; negative in October) and probably influenced by the Leeuwin Current, a prominent oceanographic feature. Our findings support broad marine spatial planning, impact assessment and the design of future surveys, which would benefit from the collection of high-resolution digital images for species identification verification. A substantial proportion of data were removed due to uncertainties resulting from non-targeted observations and this is likely to have reduced model performance. We highlight the importance of considering climatic and seasonal fluctuations in interpreting distribution patterns and species interactions in assuming habitat suitability

The Journal of Unmanned Vehicle Systems—led by its founding editor, David Bird—published its first issue in December 2013. It was the first peer-reviewed scientific journal entirely dedicated to research relating to all types of remotely piloted or autonomous robotic vehicles, including those that operate in the air, on the ground, or on or below the water’s surface. Although rare currently, it could also expand to include those that operate in outer space environments (Potter 2020). This is a uniquely eclectic field of research that encompasses multiple engineering and design aspects of the vehicles themselves in addition to a diverse and ever-growing array of practical applications of the technology...

Drones are increasingly popular tools for wildlife research, but it is important that the use of these tools does not overshadow reporting of methodological details required for evaluation of study designs. The diversity in drone platforms, sensors, and applications necessitates the reporting of specific details for replication, but there is little guidance available on how to detail drone use in peer-reviewed articles. Here, we present a standardized protocol to assist researchers in reporting of their drone use in wildlife research. The protocol is delivered in six sections: Project Overview; Drone System and Operation Details; Payload, Sensor, and Data Collection; Field Operation Details; Data Post-Processing; and Permits, Regulations, Training, and Logistics. Each section outlines the details that should be included, along with justifications for their inclusion. To facilitate ease of use, we have provided two example protocols, retroactively produced for published drone-based studies by the authors of this protocol. Our hopes are that the current version of this protocol should assist with the communication, dissemination, and adoption of drone technology for wildlife research and management.

LITTLE is known about the distribution, abundance and behavioural ecology of dolphins in the tropical north-west of Australia. This region is remote, and until recently, has had a relatively low human population. Two of Australia’s tropical coastal dolphin species, the Australian Snubfin Orcaella heinsohni and Indo-Pacific Humpback Dolphins Sousa chinensis (“Snubfin Dolphin” and “Humpback Dolphin”, hereafter) are known to occur in the region. Australia-wide, the only scientific publications on these two species come from a few studies from eastern Queensland, where both species live in “populations” of 50–100 individuals (Parra et al. 2006a; Cagnazzi et al. 2009) that are genetically isolated from one another (Parra 2011); have small home ranges; and are found in near-shore areas, typically within 3-5 km of the coastline (Parra 2006; Parra et al. 2002, 2004, 2006a,b; Cagnazzi et al. 2009). In eastern Australia, both species forage on coastal/estuarine fish and cephalopods, which is further evidence of their reliance on the near-shore environment (Parra and Jedensjö 2009). According to population sizes in Queensland, and the extent of potentially suitable habitat along the north-west coast, the total numbers in Western Australia are likely to be in the low thousands of individuals (i.e., < 5 000). The combination of these life-history characteristics may render Snubfin and Humpback Dolphins particularly vulnerable to local extinctions due to human activities such as habitat modification and increased shipping and boating activity (Frankham 2005; O’Grady et al. 2006). In this Essay, we review the current extent of coastal developments in the waters of north-west Australia. Then we discuss the conservation and management implications of this in relation to coastal dolphins, particularly Snubfin and Humpback Dolphins. We also appraise the current, non-targeted methods being used to survey marine mammal populations for environmental impact assessments (EIAs), highlightin

Australian Snubfin Orcaella heinsohni, Indo-Pacific Humpback Sousa chinensis and Indo-Pacific Bottlenose Dolphins Tursiops aduncus inhabit Australia's tropical north-western coastline, a region undergoing extensive port development associated with the massive expansion of the oil, gas and mining industries. The current lack of data on dolphin population sizes or trends precludes impact assessments of developments on these protected species. Furthermore, the Western Australian and Commonwealth Government conservation listings of tropical inshore dolphins do not reflect their international listings. From April to July, 2010, we conducted ad hoc boat-based surveys (n=55) of inshore delphinids at seven sites across north-western Australia from Coral Bay in the south (23.1°S: 113.8°E) to Cable Beach in the north (17.9°S: 122.2°E). We documented the locations of these three species from which we obtained photoidentification and biopsy data, as well as reports of Australian Snubfin Dolphin sightings from researchers and community groups. The data from this limited field effort confirm that Indo-Pacific Humpback and Indo-Pacific Bottlenose Dolphins occur in the waters adjacent to each north-western Australian urban centre and show that the range of the Australian Snubfin Dolphin extends considerably further south-west than previously reported. Given the scale of coastal developments and the vulnerability of isolated cetacean populations to fragmentation or extirpation, assessments of the viability of dolphin populations are required. Our data suggest that the Australian Snubfin, Indo-Pacific Humpback and Indo-Pacific Bottlenose Dolphins need to be considered as likely to be impacted by coastal developments across north-western Australia.

Knowledge of the diving behaviour of aquatic animals expanded considerably with the invention of time-depth recorders (TDRs) in the 1960s. The large volume of data acquired from TDRs can be analyzed using dive analysis software, however, the application of the software has received relatively little attention. We present an empirical procedure to select optimum values that are critical to obtaining reliable results: the zero-offset correction (ZOC) and the dive threshold. We used dive data from shallow-diving coastal dugongs (Dugong dugon) and visual observations from an independent study to develop and test a procedure that minimizes errors in characterizing dives. We initially corrected the surface level using custom software. We then determined the optimum values for each parameter by classifying dives identified by an open-source dive analysis software into Plausible and Implausible dives based on the duration of dives. The Plausible dives were further classified as Unrecognized dives if they were not identified by the software but were of realistic dive duration. The comparison of these dive types indicated that a ZOC of 1. m and a dive threshold of 0.75. m were the optimum values for our dugong data as they gave the largest number of Plausible dives and smaller numbers of other dive types. Frequency distributions of dive durations from TDRs and independent visual observations supported the selection. Our procedure could be applied to other shallow-diving animals such as coastal dolphins and turtles.

Disturbance from boats has been documented for many species of marine mammals, especially cetaceans, but has never been quantified for dugongs. Dugongs depend on seagrass for food. This food mostly occurs in shallow coastal areas where boat traffic is high. Thus there is potential for boats to alienate dugongs from critical habitat areas. Using an overhead video observation system (‘blimp-cam’), we observed the behaviour of focal dugongs during controlled boat pass experiments and while no boats were present. The percentage of time focal dugongs spent feeding and travelling was unaffected by boat presence, the number of boat passes and whether a pass included a stop and restart (pass continuity). The duration, distance and direction of a focal dugong's subsurface behaviour were unaffected by number, continuity or distance of boat passes. However, focal dugongs were less likely to continue feeding if the boat passed within 50 m, than if the boat passed at a greater distance. Mass movements of dugong feeding herds in response to experimental and opportunistically observed boats were timed on 42 occasions but only lasted an average of 122 s. These movements occurred in response to boats passing at a range of speeds, and at distances of less than 50 m to over 500 m. The levels of boat traffic we observed may reduce dugongs' feeding time budget by a maximum of 0.8–6%. Thus at present boats appear unlikely to be having a substantive effect on the energy intake of dugong populations at our study site on the Moreton Banks near Brisbane, Australia. However, boat traffic is likely to increase in this fast growing region, raising concern about the future impact of boats on this and other dugong populations.

Incidental bycatch in fishing nets is a global cause of incidental mortality of marine mammals. Two classes of approaches attempt to mitigate this impact: (1) approaches that change the behaviour of the fisher (e.g. closures and gear modifications), (2) approaches that attempt to change the behaviour of the bycatch species (e.g. acoustic alarms or pingers). Even though the effectiveness of pingers has been established for very few bycatch species, pingers are now mandatory in many fisheries throughout the world. Pingers are being trialled in commercial gill net fisheries in tropical Australia to reduce the bycatch of the dugong and three species of coastal dolphins, despite an absence of robust assessments of: (1) their effectiveness in reducing bycatch, (2) the likelihood of alienating bycatch species from critical habitats. We conducted replicate experiments to test the behavioural responses of dugongs to 4 and 10 kHz pingers in an array simulating a net. Each experiment comprised three sequential 10‐min treatments in which two pingers were: (1) inactive, (2) active, (3) inactive. The rate of decline of the number of dugongs within the focal arena did not change significantly while pingers were activated. Dugongs passed between the pingers (where a net would be located) irrespective of whether the alarms were active or inactive, fed throughout the experiments and did not change their orientation to investigate pinger noise, or their likelihood of vocalizing. We conclude that: (1) pingers are unlikely to alienate dugongs from critical habitats or reduce dugong mortalities in fishing nets, (2) bycatch mitigation strategies such as pingers that rely on changing animal behaviour should only be used after rigorous testing on all likely bycatch species.

Feeding free-ranging native animals is a form of wildlife-based tourism that is particularly popular in Australia as a result of the cryptic nature of many native species. The colony of Mareeba rock-wallabies (Petrogale mareeba) at 'Granite Gorge', North Queensland, where tourists feed a spatially defined subset of animals daily, was studied to determine the effects of provisioning on their behaviour and body condition. Provisioned P. mareeba had higher activity levels, including higher aggression levels, and spent more time performing contact behaviours (including mutual and non-mutual allogrooming) than did non-provisioned animals. Possible explanations for increased aggression include competition over provisioned food and territorial defence. Increased contact behaviours may serve to reduce tension caused by provisioning. The diurnal activities of the provisioned rock-wallabies were dictated by the activities of tourists. Provisioned rock-wallabies emerged from their shelters to receive food much earlier each afternoon than did the unprovisioned animals. The level of autogrooming exhibited by the provisioned wallabies was much higher than that of the unprovisioned animals, presumably as a thermoregulatory response to the high afternoon temperatures. Although provisioned P. mareeba feed more, their higher activity levels explain the lack of difference in the body condition between the two groups.