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Although the Altamaha River, Georgia, once supported one of the largest fisheries for Atlantic sturgeon Acipenser oxyrinchus in U.S. waters, the fishery was closed in 1997 because of severe overfishing. Since then, no studies have been conducted and population trends have remained unknown. The objective of this study was to estimate annual run size and age structure of the spring spawning migration and to determine genetic relatedness between this population and other Georgia populations. In spring of 2004 and 2005, we sampled the annual spawning run of Atlantic sturgeon in the lower 30 km of the Altamaha River using large‐mesh gill nets. Captured fish were marked with passive integrated transponder tags and released to facilitate a run estimate using a simple Schnabel mark‐recapture estimator. Over the 2 years of the study, we captured 213 individuals, yielding mark‐recapture run estimates of 324 (95% confidence interval [CI] = 143‐667) in 2004 and 386 (95% CI = 216‐787) in 2005. Catch curve analysis yielded annual mortality rates of 17.3% in 2004 and 21.3% in 2005. Genetic analysis showed that the Altamaha River population is distinct from neighboring populations in the Ogeechee and Savannah rivers. The results of this study suggest that after 10 years of federal protection, the Altamaha River population of Atlantic sturgeon appears to be in the early stages of recovery; however, the genetic diversity of the population is surprisingly low. Future studies are needed to monitor population dynamics and genetic structure of the stock to ensure complete recovery.

Recording -Reporting -Safety -Education and training -EthicsThe GCCP documents formed a major basis for a GLP advisory document for in vitro studies published by the OECD (2005).In 2007, following the increasing use of technologies to culture human embryonic and pluripotent stem cells, the ECVAM Task Force was re-formed to produce a special supplementary GCCP document on considerations for good practice in the culture of human pluripotent stem cells "Human embryonic stem cell (hESC) technology for toxicology and drug development: summary of current status and recommendations for best practice and standardization. The Report and Recommendations of an ECVAM Workshop" 1 .More recently, two OECD working groups proposed a revision of GCCP and a series of taskforce workshops were held around the world to consider the needs for new GCCP principles to address the new cellular, molecular and engineering tools, which had come into common use since 2005. This led to an OECD Guidance Document on Good In Vitro Method Practices (GIVIMP) (OECD, 2018). The guidance cross-references and appends the at that time available GCCP documents (Eskes et al., 2017).Under the leadership of the Johns Hopkins Center for Alternatives to Animal Testing (CAAT), two workshops were held in 2015 in Baltimore, USA, and Konstanz, Germany, as part of the

SummaryThe Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus Mitchill, 1815) is an anadromous sturgeon species, yet little is known with regard to its osmoregulatory ability and habitat use at early life stages. In order to examine whether salinity poses a physiological challenge to juvenile Atlantic sturgeon near the sizes where they may begin to move into saline habitats, growth and osmoregulatory ability were tested. Juvenile Atlantic sturgeon (mean initial weight: 440 g) were acclimated to one of three salinity conditions (0, 10, or 33 ppt) representing the range of salinities they would be expected to encounter. Growth was measured over a 6-month period, and osmoregulatory ability (i.e. blood plasma osmolality and ionic concentrations) was measured after 4 months. Mean weight and length increased in all treatments, but fish in 0 and 10 ppt grew more than fish in 33 ppt. Blood plasma osmolality was regulated at similar levels regardless of salinity. Therefore, juvenile Atlantic sturgeon have the physiological capability to move between salinity habitats, but grow faster in low salinities.

Summary This study evaluated the effects of environmental parameters on the probability of capturing endangered pallid sturgeon (Scaphirhynchus albus) using trotlines in the lower Mississippi River. Pallid sturgeon were sampled by trotlines year round from 2008 to 2011. A logistic regression model indicated water temperature (T; P < 0.01) and depth (D; P = 0.03) had significant effects on capture probability (Y = −1.75 − 0.06T + 0.10D). Habitat type, surface current velocity, river stage, stage change and non‐sturgeon bycatch were not significant predictors (P = 0.26–0.63). Although pallid sturgeon were caught throughout the year, the model predicted that sampling should focus on times when the water temperature is less than 12°C and in deeper water to maximize capture probability; these water temperature conditions commonly occur during November to March in the lower Mississippi River. Further, the significant effect of water temperature which varies widely over time, as well as water depth indicate that any efforts to use the catch rate to infer population trends will require the consideration of temperature and depth in standardized sampling efforts or adjustment of estimates.