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Flatback turtles (Natator depressus) are endemic to northern Australia, but their movements at sea have remained understudied. Here, we compiled one of the world's largest single‐species satellite tracking datasets (n = 280 transmitters, deployed between 2005 and 2020) to investigate the movements and level of spatial protection afforded to five flatback genetic stocks across Western Australia during different behavioral phases (i.e., inter‐nesting, migration, and foraging). Flatbacks spent 99.5% of their time in Australian waters and are provided with a very high level of spatial protection (>98% overlap with Biologically Important Areas) during the inter‐nesting phase of their life cycle. Up to 85.6% and 59.1% overlap between marine reserves and the foraging and migratory ranges for flatback stocks, respectively, was found. However, our results identified additional foraging and migratory areas where protective measures would benefit multiple stocks at once. The detailed flatback distribution maps produced here will be key resources for managers and researchers and highlight the benefits of collaborative multi‐agency studies. Additionally, this work provides a useful analytical framework for future studies endeavoring to complete large‐scale, multi‐stock spatial distributions and overlap assessments for populations of conservation concern. [ABSTRACT FROM AUTHOR]

Abstract: Estuarine habitats provide rearing opportunities for the juvenile life stage of anadromous fishes. Because survival is positively correlated with juvenile performance, these estuarine habitats play an important role in population abundance and productivity. To provide information for the recovery of several depressed stocks of Chinook salmon in the Columbia River Basin, we sought to identify the factors that explain variability in performance. Using otolith‐derived estimates of juvenile somatic growth rate as an index of recent performance, we observed a negative nonlinear relationship between growth rate and day of year, and a decreasing and increasing trend of growth rate over the 8 years of this study and distance from the river mouth respectively. Using a generalised linear modelling approach, we found that variability in juvenile somatic growth rate was best explained by where and when individuals were collected, their body size, contaminant loads, stock of origin, and whether a fish was hatchery produced or unmarked. Lastly, we argue that a considerable improvement to the growth rate of juveniles in estuarine habitats is physiologically possible. The results of this 8‐year study provide a baseline of the performance of juvenile Chinook salmon to evaluate habitat restoration programs and to compare against future anthropogenic conditions. [ABSTRACT FROM AUTHOR]

In parts of the Indo-Pacific, large-scale exploitation of the green turtle Chelonia mydas continues to pose a serious threat to the persistence of this species; yet very few studies have assessed the pattern and extent of the impact of such harvests. We used demographic and genetic data in an age-based model to investigate the viability of an exploited green turtle stock from Aru, south-east Indonesia. We found that populations are decreasing under current exploitation pressures. The effects of increasingly severe exploitation activities at foraging and nesting habitat varied depending on the migratory patterns of the stock. Our model predicted a rapid decline of the Aru stock in Indonesia under local exploitation pressure and a shift in the genetic composition of the stock. We used the model to investigate the influence of different types of conservation actions on the persistence of the Aru stock. The results show that local management actions such as nest protection and reducing harvests of adult nesting and foraging turtles can have considerable conservation outcomes and result in the long-term persistence of genetically distinct management units. [ABSTRACT FROM AUTHOR]