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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.

AbstractInundation of Australian freshwater turtle nests has been identified as a threat to recruitment and long-term viability of species such as the critically endangered white-throated snapping turtle (Elseya albagula). Water level fluctuations within water storage infrastructure can inundate significant proportions of E. albagula nests in any year. Using an ecological risk assessment framework, operating rules for a water storage in the Burnett River (South East Queensland, Australia) were implemented to support nesting of E. albagula. Turtles were encouraged to nest at higher elevations on riverbanks by maintaining higher water levels in the impoundment during the nesting season, followed by lowering of water levels during the incubation period to minimise rates of nest inundation from riverine inflows. To verify the success of the new rules, a three-year confirmation monitoring program of nest heights and water levels was undertaken. Results of confirmation monitoring showed that 3% (2018), 11% (2019) and 0% (2020) of E. albagula nests were inundated under the new operating rules, compared to previously estimated nest inundation rates of >20% in ~24% of years of a 118-year simulation period (1890–2008) under previous storage operating rules. Emergency releases from an upstream storage in 2019 and 2020 for dam safety did not affect the success of the rule, demonstrating its resilience to natural and artificial flow regimes. This study demonstrates the importance of confirmation monitoring in verifying the efficacy of targeted changes to water management, and highlights potential application across other water storage infrastructure with threatened freshwater turtle populations requiring adaptive management.

The remote tracking of endangered animals is often justified by the application of movement data to conservation problems, but examples of where scientific findings have rapidly informed conservation actions are relatively rare. In this study we satellite tracked 30 adult female hawksbill turtles (Eretmochelys imbricata) that were captured after nesting in the Arnavon Community Marine Park (ACMP), Solomon Islands. Ten hawksbill turtles were tagged in April 2016, ten in May 2017 and ten in November 2018. Our primary aim was to determine if the ACMP boundaries that were demarcated in 1995 were large enough to protect female hawksbill turtles throughout their entire nesting season. Our home range analysis revealed that collectively, tracked hawksbill turtles spent 98.5% of their inter-nesting season within the ACMP, confirming that the original park boundaries were adequate. Our first year's results were shared with community and government stakeholders and assisted in getting the ACMP declared as the Solomon Islands first national park in May 2017. Our fine scale analysis of inter-nesting habitats also highlighted that most hawksbill turtle nests were being laid on an island in the ACMP that did not have a permanent ranger presence and was experiencing persistent poaching. Based on this finding an additional ranger station was established on this uninhabited island and staffed with community rangers in 2017. Our study demonstrates how involving community, government and NGO stakeholders in applied research can lead to results being rapidly utilised to inform policy and conservation practice as soon as they become available.