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Managing impacts to threatened species is challenging, because it is intrinsically linked to resources, knowledge, capacity and public and government will. A key tool often used in species conservation is a recovery or management plan. Yet all too often, plans are not designed for evaluation and not tested against quantitative criteria. Our study takes a novel approach to recovery plan assessment by assembling a worldwide database of recovery plans for a single taxon. We obtained 79 recovery or management plans for marine turtles and then designed criteria to assess and compare them for their ability to be evaluated and thus successfully implemented. We then used expert opinion of marine turtle specialists to weigh our 18 criteria. Overall, we found that the failure to adequately integrate adaptive management into plan design was a major shortcoming of marine turtle recovery planning (>90% of plans). Other common gaps included inadequacy of measurable objectives (75% of plans) and an absence of timelines (50% of plans). We highlight knowledge gaps relating to status trends, critical habitat and a lack of incorporation of social aspects such as stewardship and education. Our research underlines the importance of recovery planning from multiple scales and provides a step towards designing recovery plans that include SMART (specific, measurable, achievable, realistic and time-bound) objectives; scientific information; social aspects; and evaluation. We highlight the importance of national and multi-national planning processes to produce internationally relevant plans that will maximise conservation efforts for a globally threatened marine species.

Offshore interactions of inter-nesting flatback turtles Natator depressus with resource industry activities are potentially frequent, yet the associated impact is largely unquantified. Consequently, there is a need to understand the degree of interaction and to provide data that can assist with effective conservation and management. We used satellite tracking to highlight the potential interaction of inter-nesting flatback turtles (n = 56) from 4 rookeries in Western Australia with regional resource industry activities. Flatback turtles demonstrated varying inter-nesting movements, with displacement distances ranging from 3.4 to 62.1 km. Some turtles at all 4 rookeries remained <10 km from the nesting beach. Core home range areas for inter-nesting flatback turtles ranged from 1.4 to 601.1 km2. The proportion of core home range areas for Thevenard and Barrow Island turtles that overlapped offshore petroleum title areas was 85.7 and 88.6%, respectively. The proportion of median daily positions that overlapped petroleum title areas was also high, 80.8% (Thevenard) and 87.3% (Barrow). There was no overlap of home range areas and median daily positions with petroleum title areas for Mundabullangana and Port Hedland turtles, although some inter-nesting movements of Port Hedland turtles were in close proximity to a proposed port expansion. The wide-ranging inter-nesting movement patterns highlight a need for the Australian Government and industry to expand the scope of Environmental Impact Assessments, ensuring adequate protection is provided to inter-nesting flatback turtles. The similar nearshore inter-nesting movement pattern recorded by some flatback turtles at each rookery provides an opportunity to establish boundaries for small-scale spatial and temporal protection measures.

In 2004 the Australian Government implemented a revised zone-based management plan for the Great Barrier Reef World Heritage Area to increase protection of representative areas while minimising the impacts to the economic viability of important industries. In this study we evaluated the current zoning plan for its capacity to protect marine turtles from commercial trawling and netting activities at nesting sites and at inshore and offshore foraging areas to assess whether the Great Barrier Reef Marine Park Authority met their obligations under the Representative Areas Program (RAP). We found that protection from commercial fisheries increased within 5- and 10-km buffer zones of all very-high, high- and medium-priority nesting sites that were previously less than 100% protected. However, three very-high-priority sites and six high-priority sites remain less than 100% protected out to 5 km, falling short of the objectives of the RAP. There were variable increases in protection at foraging areas; however, each of them increased in the proportion of area protected from commercial fishing, fulfilling the objectives of the RAP. By using a broader-scale fisheries by-catch dataset as a proxy for turtle abundance we found that improvements in protection are not species-specific and can be attributed to the step-wise increases in protection since the mid 1990s.

Meaningful stakeholder engagement is important to collaborative decision-making and to effective polycentric governance, particularly when managing cross-scale environmental issues like those involving marine migratory species. In this paper, we explore the barriers to, and opportunities for, stakeholder involvement in the governance of threats to marine migratory species in eastern Australia, using semi-structured qualitative interviews and a focus group, as an example of the generic problem of managing migratory species within a large range state with multiple jurisdictions. Respondents identified several barriers to, and opportunities for, improved stakeholder involvement in the governance of marine migratory species, corresponding to 4 main themes: decision-making processes, information sharing, institutional structures, and participation processes. Respondents indicated that the governance system protecting marine turtles, dugongs, humpback whales, and non-threatened migratory shorebirds in eastern Australia would benefit from the introduction of new information pathways, reformed institutional structures (including environmental legislation), and improved participatory pathways for non-government stakeholders. Such changes could help harmonise the process of managing these species, leading to more effective conservation management throughout their range.

Context Numerous studies show that artificial light disrupts the sea-finding ability of marine turtle hatchlings. Yet very little has been published regarding sea-finding for flatback turtles. Given the current industrialisation of Australia's coastline, and the large potential for disruption posed by industrial light, this study is a timely investigation into sea-finding behaviour of flatback turtle hatchlings. Aims We investigate sea-finding by flatback turtle hatchlings in relation to ambient light present in areas of planned or ongoing industrial development, and evaluate the fan and arena-based methods that are frequently used for quantifying hatchling dispersion. Methods Using a combination of methods, we assessed the angular range and directional preference of sea-finding hatchlings at two key flatback turtle rookeries, Peak and Curtis Islands, during January–February 2012 and 2013, and at Curtis Island in January 2014. Relative light levels at each site were measured using an Optec SSP-3 stellar photometer, and moon phase, moon stage and cloud cover were also recorded. Key results We found no evidence of impaired hatchling orientation, and observed very low levels of light at Peak Island. However, at Curtis Island, hatchlings displayed reduced sea-finding ability, with light horizons from the direction of nearby industry significantly brighter than from other directions. The sea-finding disruption observed at Curtis Island was less pronounced in the presence of moonlight. Conclusions The reduced sea-finding ability of Curtis Island hatchlings was likely due to both altered light horizons from nearby industry, as well as beach topography. Both methods of assessing hatchling orientation have benefits and limitations. We suggest that fan-based methods, combined with strategically placed arenas, would provide the best data for accurately assessing hatchling sea-finding. Implications Sky glow produced by large-scale industrial development appears detrimental to sea-finding by flatback turtle hatchlings. As development continues around Australia's coastline, we strongly recommend continued monitoring of lighting impacts at adjacent turtle nesting beaches. We also advise rigorous management of industrial lighting, which considers cumulative light levels in regions of multiple light producers, as well as moon phase, moon-stage, cloud cover and time of hatchling emergence. All these factors affect the likelihood of disrupted hatchling sea-finding behaviour at nesting beaches exposed to artificial light-glow, industrial or otherwise.

Context Hawksbill sea turtles (Eretmochelys imbricata) are conservation-dependent species in many areas of the world. A key component to ensuring successful conservation initiatives for the species is understanding their distribution and habitat use, in particular, knowing the nesting sites, migration routes and foraging areas for each genetic stock, and how these might overlap with threats. Aims Investigate the post-nesting movements of hawksbill sea turtles nesting in the Torres Strait, including migration movements and foraging ground size and distribution. Methods Nine nesting hawksbill turtles of the north-eastern Australian genetic stock were satellite-tagged between the 2010 and 2019 nesting seasons for 182 ± 143 days (mean ± s.d.). Key results Three turtles continued to nest on adjacent islands before commencing their post-nesting migrations. From the nine tracked turtles, the following three migration movement strategies were identified: (1) direct migration between the nesting beach and foraging ground, (2) non-direct movements with a period of meandering, and (3) establishment of two foraging areas separated by direct movement pathways. Foraging grounds were distributed across the Torres Strait and north-eastern Australia and varied in size between 0.54 km2 and 3.31 km2 (95% UD). None of the turtles migrated outside of Australian waters. Conclusions The localisation of these movements and habitats within Australian waters provides a unique conservation opportunity, whereby protection efforts involve multiple life stages and potentially preserve turtles from multiple genetic stocks. The variety of inter-nesting, migration and home range strategies used by the tracked turtles in the present study highlight the broad scope of hawksbill movements. Implications Our findings are useful for the implementation of future marine conservation areas and shed light into the nesting, migratory and foraging behaviours of hawkbills from this genetic stock. An understanding of the movement tracks and habitats used by a genetic pool is essential for well grounded implementation of conservation areas and management regulations.