Study: Spiny Lobster Larvae Spread Holds Key to Improving Fisheries Management
Origin and destination of spiny lobster larvae, valuable commercial species in the Caribbean, revealed
Washington, DC — Management of the spiny lobster, the most important commercial fishery in the Caribbean, can be improved if larval dispersal and genetic information is considered in population assessments, according to a new study published in Scientific Reports by scientists of the National Museum of Natural History-Smithsonian Institution, Florida Fish Wildlife Conservation Commission, Rare, and other organizations.
Limited management and chronic overfishing of the Caribbean spiny lobster (Panulirus argus), has led to declines across the region. Spiny Lobster can, however, be resilient to local fishing pressure thanks to the strong and widespread connections among populations within the region that can supply new larvae to depleted areas. But, understanding these regional connections is critical to supporting regional management at the appropriate scale.
“Mapping larval origins of Caribbean spiny lobster is crucial,” said Dr. Iris Segura-Garcia, a post-doctoral research fellow at the National Museum of Natural History – Smithsonian Institution, and lead author of the paper. “Determining where the lobster larvae go and where they came from, can tell us where to focus resources for effective management to increase overall fisheries production.”
“Knowledge on larval dispersal, population dynamics and the connectivity caused by ocean currents are crucial to developing appropriate management strategies for fisheries,” said Dr. Steve Box, Senior Vice President of Rare’s Fish Forever Program, and co-author on the paper. “Understanding how populations are connected in space and through time, helps highlight that management is often needed both locally and regionally to secure fish recovery. This type of information is also essential to inform the design of networks of reserves that aim to sustain both local and regional populations.”
The larvae of the Caribbean spiny lobster can spend up to 9 months in the plankton moving on ocean currents. This is the longest known pelagic larval phase of any marine invertebrate and means that larvae can travel great distances from where they spawned crossing international boundaries. At the end of this journey lobster swim from oceanic waters to the coast to settle in shallow habitats such as mangroves and seagrass beds before moving on to coral reefs as they grow.
The study explored for the first time the genetic variability of the spiny lobster at fine temporal scale across the Caribbean. The authors collected genetic information of more than 2000 newly settled post-larvae and about 800 adult lobsters from the Florida Keys and throughout the Caribbean to determine genetic relationships. They also mapped the probable movements of lobster throughout the Caribbean using oceanographic current models.
The authors found strong population connectivity among countries in the North and Central Caribbean, Central America, and Florida. But, more surprisingly the results suggest that Florida’s lobster population is also supported by larvae coming from local populations meaning that despite the long time they spend in the plankton the lobster stay retained in local currents.
The study, titled “Reconstruction of larval origins based on genetic relatedness and biophysical modeling,” is an open access paper.