Sci-Café: The Blue Crabs of Apalachicola Bay

Dr. Andy Gannon from the Dauphin Island Sea Lab presented “The Blue Crabs of Apalachicola Bay” during the Apalachicola Reserve’s September Sci-Café on September 24th, 2026. Dr. Gannon began the presentation by discussing the life cycle of blue crabs, and in particular how salinity influences their distribution in Apalachicola Bay. Blue crabs spend the start of their life offshore as plankton, before moving into the less saline bay environment for the remainder of their lives. Adult female crabs move to the mouths of the bay to release larvae and complete the cycle. Juveniles peak twice a year, in December through March and July through August, while adults peak in the summer. 

Understanding these life cycle trends, Dr. Gannon then transitioned the discussion to how droughts across recent decades and reduced fresh water flows from the Apalachicola system correlated with reduced catch per unit effort (CPUE) of adult blue crabs. He also discussed the additional threat of sand buildup in East Bay that covers organic material and vegetation, which are important habitats for juvenile blue crabs. One final threat to blue crabs discussed during the presentation was barnacles, which can grow in the gill chambers of crabs, reducing respiratory efficiency, and cause additional stress to the crab, making them more likely to die. 

In total, 17 people attended the talk. ANERR hosts a Sci-Café webinar monthly on a variety of topics. To register for upcoming Sci-Cafes go to our website events calendar at https://www.apalachicolareserve.com/events/. To see past Sci-Cafés go to https://www.apalachicolareserve.com/previous-events/.