The effect of increased acidity on Atlantic blue crab (Callinectes sapidus) embryonic development

Abstract:

The commercial importance of the Atlantic blue crab (Callinectes sapidus) underscores the need for understanding their response to coastal pollution. Acidification resulting from anthropogenic sources is one such pollutant potentially affecting their life cycle. Currently there are no studies evaluating blue crab embryonic changes in response to reducing pH. In this study, embryos obtained from the Eastern Shore of Virginia were placed in varying acidities (pH 6.8, 7.4 & 8.1) and observed over 16 days for changes in development time, final yolk size, hatching day, hatching success, and embryo volume. At low pH (6.8), embryonic development was delayed and hatching day was impaired, with no changes in hatching success, final yolk size or embryo volume compared with control pH (8.1). At medium pH (7.4), hatching day was impaired, with no impact on hatching success, development, final yolk size, or embryo volume. These outcomes show a negative effect of extremely low pH on embryonic development, although the observed delays were minimal and unlikely to impact the species on a population level, with hatching day similarly related. Although not statistically different in treatment conditions, hatching success was reduced at low and medium pH (50% & 33%, respectively) compared with control conditions (100%). In the future, combining multiple stressors such as temperature and salinity will be important factors to consider in subsequent studies that seek to understand their response to multiple environmental changes.