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For long-lived species such as marine mammals, having sufficient data on ranging patterns and space use in a timescale suitable for population management and conservation can be difficult. Yawuru Nagulagun/Roebuck Bay in the northwest of Western Australia supports one of the largest known populations of Australian snubfin dolphins (Orcaella heinsohni)—a species with a limited distribution, vulnerable conservation status, and high cultural value. Understanding the species’ use of this area will inform management for the long-term conservation of this species. We combined 11 years of data collected from a variety of sources between 2007 and 2020 to assess the ranging patterns and site fidelity of this population. Ranging patterns were estimated using minimum convex polygons (MCPs) and fixed kernel densities (weighted to account for survey effort) to estimate core and representative areas of use for both the population and for individuals. We estimated the population to range over a small area within the bay (103.05 km2). The Mean individual representative area of use (95% Kernel density contour) was estimated as 39.88 km2 (± 32.65 SD) and the Mean individual core area of use (50% Kernel density contour) was estimated as 21.66 km2 (±18.85 SD) with the majority of sightings located in the northern part of the bay less than 10 km from the coastline. Most individuals (56%) showed moderate to high levels of site fidelity (i.e., part-time or long-term residency) when individual re-sight rates were classified using agglomerative hierarchical clustering (AHC). These results emphasize the importance of the area to this vulnerable species, particularly the area within the Port of Broome that has been identified within the population’s core range. The pressures associated with coastal development and exposure to vessel traffic, noise, and humans will need to be considered in ongoing management efforts. Analyzing datasets from multiple studies and across time could be beneficial

The Kimberley marine environment in Western Australia is widely recognised for its outstanding natural features, vast and remote sea and landscapes, and Indigenous cultural significance. To ensure that adequate baseline information is available to understand, monitor and manage this remote and relatively understudied region, scientific exploration was undertaken between 2012 and 2018 as part of the Kimberley Marine Research Program (KMRP). Whilst this program generated significant amounts of new knowledge about the region, important research gaps remain, that if answered, should improve the capacity of managers to conserve the region's values more effectively. Here, we apply established participatory horizon scanning methods to draw on the expertise and understanding of 24 scientists and 18 managers (12 natural resource managers and 6 healthy country managers) involved in the KMRP, and assess their most essential remaining research needs for informing management of the region. Through this process, we identify a total of 184 research questions spanning seven themes: (i) habitats, (ii) fauna, (iii) ecological processes, (iv) pressures, (v) management, (vi) oceanography, and (vii) geomorphology. Of the 184 questions that formed the basis of this study, 29% related to the theme of ‘management’, followed by questions relating to ‘fauna’ (21%) and ‘pressures’ (20%). Questions assigned to the theme of ‘habitats’ (13%), ‘ecological processes’ (10%), and ‘oceanography’ (6%) were less common, whilst questions that related to ‘geomorphology’ only constituted 1% of all questions provided by study participants. Subtle differences in the types of questions posed by the scientist and manager groups were also evident, with questions relating to ‘ecological process’ and ‘oceanography’ overwhelmingly provided by scientists; questions in the themes ‘fauna’ and ‘management’ were mainly provided by Healthy Country Managers; and questions posed by natural resource managers were distribu

The Kimberley marine environment in Western Australia is widely recognised for its outstanding natural features, vast and remote sea and landscapes, and Indigenous cultural significance. To ensure that adequate baseline information is available to understand, monitor and manage this remote and relatively understudied region, scientific exploration was undertaken between 2012 and 2018 as part of the Kimberley Marine Research Program (KMRP). Whilst this program generated significant amounts of new knowledge about the region, important research gaps remain, that if answered, should improve the capacity of managers to conserve the region's values more effectively. Here, we apply established participatory horizon scanning methods to draw on the expertise and understanding of 24 scientists and 18 managers (12 natural resource managers and 6 healthy country managers) involved in the KMRP, and assess their most essential remaining research needs for informing management of the region. Through this process, we identify a total of 184 research questions spanning seven themes: (i) habitats, (ii) fauna, (iii) ecological processes, (iv) pressures, (v) management, (vi) oceanography, and (vii) geomorphology. Of the 184 questions that formed the basis of this study, 29% related to the theme of ‘management’, followed by questions relating to ‘fauna’ (21%) and ‘pressures’ (20%). Questions assigned to the theme of ‘habitats’ (13%), ‘ecological processes’ (10%), and ‘oceanography’ (6%) were less common, whilst questions that related to ‘geomorphology’ only constituted 1% of all questions provided by study participants. Subtle differences in the types of questions posed by the scientist and manager groups were also evident, with questions relating to ‘ecological process’ and ‘oceanography’ overwhelmingly provided by scientists; questions in the themes ‘fauna’ and ‘management’ were mainly provided by Healthy Country Managers; and questions posed by natural resource managers were distribu

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.

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.

To make behavioural ecology useful to wildlife management the gap between science and management must be bridged. This study investigated association patterns in bottlenose dolphins in Bunbury, Western Australia. Understanding how these associations varied across time and space enabled the identification of temporal and spatial locations of high conservation value. To achieve this, boat-based surveys were conducted year-round on line transects over a 120km2 study area (33° 20' S, 115° 38' E). In total, 777 dolphin groups (N=212 transects) were encountered between March 2007 and February 2010. Of the 144 adult dolphins identified, 71 were of known sex and were sighted ≥ 5 times and analysed. To measure the temporal stability of adult dolphin association patterns we calculated the Lagged Association Rates using SOCPROG 2.3. Adult female-female Lagged Association Rates remained consistently higher and stable than the null association rate over three years. The Lagged Association Rates for adult females showed a distinct seasonal cyclic pattern, peaking each summer. In winter, the density (calculated using kernel density ArcGIS 9.2) of adult females was even across the study area but in summer this contracted to hotspots in the Bunbury inner waters. The study highlighted three key findings. Firstly, habitat use changed seasonally with adult dolphins aggregating in the Bunbury inner waters in the warmer months. Secondly, strong seasonal bonds formed between adult females at this time. Lastly, the timing of female sociality and use of the inner waters coincided with the peak in calving. The distribution of dolphins is predictable in both time (warm months) and space (Bunbury inner waters) and coupled with the significance of the seasonal female sociality and calving, identified an area of high conservation value. We recommend that these findings be incorporated into management strategies to conserve the dolphin population.

The space an animal uses and needs for survival is a key concept in wildlife management. Animals within a population do not use their space equally and the size of their home range area and how they use it are important considerations in wildlife management. Home range areas for individual dolphins were estimated using the Kernel Density Estimator and Minimum Convex Polygon methods. Home range size differed between adult male and female dolphins, with males having larger home ranges than females. Females in sheltered inner waters (Leschenault Estuary and Koombana Bay) had smaller home ranges (7.4-24.6km2; N=9) than those females in exposed coastal areas (home ranges: 32.1-125.2km2; N=9). The difference in home range size between adult females was statistically significant (ANOVA: P ≤0.0001). Seasonal differences in ranging patterns showed females had a preference for the lee-side of an artificial groyne adjacent to the Leschenault Estuary cut during the summer and autumn calving season. Habitat use was explored through maximum entropy modelling. Reef habitat had the strongest influence over dolphin presence whilst distance from coast was a weak predictor. Males and some adult females used a larger coastal area. The female dolphins whose small home ranges were exclusively within the inner waters may be at greater risk of threats such as coastal development, vessel strikes, entanglement in fishing gear and compromised water quality. Given these findings, both the coastal and inner water ecosystems are important and management strategies should incorporate both areas to effectively conserve the dolphin population.

Marine protected areas (MPAs) are a primary policy instrument for managing and protecting coral reefs. Successful MPAs ultimately depend on knowledge-based decision making, where scientific research is integrated into management actions. Fourteen coral reef MPA managers and sixteen academics from eleven research, state and federal government institutions each outlined at least five pertinent research needs for improving the management of MPAs situated in Australian coral reefs. From this list of 173 key questions, we asked members of each group to rank questions in order of urgency, redundancy and importance, which allowed us to explore the extent of perceptional mismatch and overlap among the two groups. Our results suggest the mismatch among MPA managers and academics is small, with no significant difference among the groups in terms of their respective research interests, or the type of questions they pose. However, managers prioritised spatial management and monitoring as research themes, whilst academics identified climate change, resilience, spatial management, fishing and connectivity as the most important topics. Ranking of the posed questions by the two groups was also similar, although managers were less confident about the achievability of the posed research questions and whether questions represented a knowledge gap. We conclude that improved collaboration and knowledge transfer among management and academic groups can be used to achieve similar objectives and enhance the knowledge-based management of MPAs. © 2012 Elsevier Ltd.

As delphinid populations become increasingly under threat we rely on our capacity to produce accurate estimates of abundance and distribution with which to make management decisions. Many studies have favoured population models where the underlying model assumptions of population closure may be violated due to the movements and biology of the species. This study applied the Robust Design and used photo-identification as a capture-recapture method for estimating abundance, demographic parameters and temporary emigration of an Indo-Pacific bottlenose dolphin (Tursiops aduncus) population between 2007 and 2009. Surveys were conducted along pre-determined transect lines over a 120 km2 study area and occurred year-round through all austral seasons. The model with Markovian temporary emigration was favoured with all other parameters (survival, capture probability and emigration time) varying. Abundance estimates varied seasonally with a low of 65 (± SE 8.53, 95% CI: 54 to 90) in winter 2007 and a high of 139 (± SE 3.41, 95% CI: 134 to148) in autumn 2009. The overall survival estimate was 0.985 (± SE 0.006, 95% CI: 0.964 to 0.994). The abundance estimates provide a baseline for monitoring this population and should be used to parameterise future population viability analyses. These methods set a precedent for abundance estimation of dolphins using a systematic approach with intensive and consistent survey effort year round. The findings show that temporary emigration of individual dolphins from an area can result in different estimates of dolphin abundance seasonally. These modelling techniques could be applicable to population studies of coastal delphinids elsewhere. Given the current rate of coastal development in Western Australia this approach is highly relevant to Environmental Impact Assessment for evaluating impacts on coastal dolphin populations.

In the absence of guidelines or government regulation for a rapidly expanding industry, dolphin watching operators in Port Stephens, New South Wales, Australia, formulated and adopted a voluntary code of conduct in 1996. This code was designed to reduce perceived pressures on dolphins and was updated to conform to the Australian National Guidelines for Cetacean Observation when they were released in 2000. Compliance to this code of conduct was assessed in a shore-based survey over the austral summer of 2002/03. Operator compliance was generally high for: number of dolphin watching boats per dolphin school; time spent by individual operators with dolphins; method of approach to dolphins; and frequency of cruises conducted per day. However, operators did not discriminate between dolphin schools containing calves and those that did not (equating to a breach of the national guidelines) and three of nine regular operators committed most breaches of the code, particularly with regard to boat-handling around dolphins and frequency of cruises conducted per day. The code’s aim in reducing exposure of dolphins to boats was not achieved as dolphin schools were subject to consecutive approaches by numerous boats and interactions also involved boats to which the code did not apply. This voluntary code is thus of limited value without revision, education and enforcement. The inability of a voluntary code to manage the number of operators and other watercraft highlights the need for management alternatives that will increase compliance by all users of the waterways. Furthermore, widespread assessments of compliance are necessary, particularly where assessments of the effects of cetacean-based tourism are being conducted. To determine whether identified impacts are a result of inappropriate management strategies, or non-compliance with suitable management, requires that management strategies are tested while simultaneously testing or ensuring compliance.

This is an author's accepted manuscript of: Cvitanovic, C., Mackay, M., Kelly, R., Wilson, S. K., Waples, K., Nash, K. L., . . . Mathews, D. (2021). Thirty critical research needs for managing an ecologically and culturally unique remote marine environment: The Kimberley region of Western Australia. Ocean & Coastal Management, 212, article 105771.https://doi.org/10.1016/j.ocecoaman.2021.105771