Nursery Habitat for Juvenile Halibut
By, Lee Reeve, M.S. Student
Being a tiny fish isn't easy! Throughout the course of their lives, many fishes move from the open ocean to coastal nursery habitats, and then back to deep off-shore areas. All that traveling leaves them vulnerable to lots of predators and variable food resources. Fish mortality is especially high when they’re very young, so ending up in a nursery habitat with plenty of food and places to hide from predators is critical to allow them to grow up to be successful adults. The goal of my research
is to determine the pros and cons of the coastal nurseries available to juvenile California halibut in San Diego. I conduct experiments in San Diego Bay to learn about juvenile halibut habitat preference, and about their ability to find prey and avoid predators in different habitat types.
Lee and Alex collect and measure juvenile halibut using a beach seine.
Unlike most fishes, halibut are flat and have both eyes on the same side of their head. This body plan allows them to sit on the bottom, where their dappled-brown color helps them to blend into the sediment. Because halibut are so well camouflaged in sandy habitat, benefits of highly-structured habitat like eelgrass has been largely overlooked, despite its well-documented benefits to other juvenile marine organisms. Eelgrass provides rich prey resources and lots of hiding places. My research shows that access to eelgrass and to sandy habitat may be important to halibut.
Juvenile halibut show a strong preference for eelgrass in habitat choice experiments, but their survival is significantly higher in sandy habitat where they can bury themselves easily. To read the full article, click here
A day in the life...
I think jumping in the ocean is the best possible way to start the day. I usually get to the CMIL
early and head straight to my field site in San Diego Bay with a dive buddy (often another grad student in the Hovel Lab
). All my experiments are done underwater
, so we put on our SCUBA gear and descend! After setting up experiments or collecting data, we head back to the beach and pull a large net called a seine through the water to collect halibut to use in later experiments.
Alex helps beach seine for juvenile fish.
Back at the CMIL, I spend the rest of my day taking care of the fish I keep there, building and repairing field equipment, sorting and identifying samples of halibut prey under the microscope, and working on other Hovel Lab projects.
To read the full article about Lee and her research click here.
: Lee Reeve, M.S. Student, contact at firstname.lastname@example.org