Mechanisms regulating phenotypic plasticity in a highly social hermaphroditic fish – Deepwater Conservation Initiative in conjunction with Idaho State University Wrigley Marine Science Center, Santa Catalina Island, California USA
Submitted by: Sean Hopewell, CEO & Founder, Deepwater Conservation Initiative
Background
In 2024, Deepwater Conservation Initiative teamed up with Idaho State University to conduct research on blue-banded gobies, Lythrypnus dalli, off the coast of California. Research is conducted both at the Wrigley Marine Science Center (WMSC) on Santa Catalina Island, CA and the Idaho State University campus in Pocatello, Idaho.
The blue-banded goby is a serially hermaphroditic marine species whose behavior and associated steroid changes can be closely examined during courtship and in social groups. The project, led by Dr. Devaleena Pradhan, is examining behaviors and hermaphroditic changes in L. dalli to correlate with reproductive success in the species. Research is performed from June through August.
Research
The Deepwater Scientific Dive Team is responsible for collecting individuals for the project. Utilizing multiple sites in the ecosystems located off the Catalina Island coast, our team uses a mild sedation to anesthetize the target groups. Once anesthetized, the gobies are collected by fine mesh nets and quickly transferred to a collection container. The target depth for most collection sites are between 30 and 60 feet of sea water. The collected specimens are then transferred to a larger collection container with fresh sea water at the surface.
At the WMSC Lab, collected animals are divided into target fish groups to induce mating and parental behaviors. The research team will then make morphological assessments, behavior observations, record body measurements, and perform dissections and surgeries when needed.
Dr. Pradhan began studying L. dalli in 2009, and has been successfully correlating hormone levels with mating and parenting behaviors. Specifically, the results show evidence that 11-ketotestosterone (KT) levels are directly related to parenting behaviors while carbenoxolone (CBX) inhibits these behaviors in teleost fish. The research project is also exploring the importance of other enzymes as mechanisms in local steroidogenesis. Results of these studies will not only give insight into the reproductive success of teleost fish but could have broader implications on human hormone therapy.
For the Deepwater Conservation Initiative, this project has helped develop a template for pursuing additional research projects with partner institutions and fine tune the skills of our scientific divers. We have had the opportunity to work with multiple state entities which gave insight into policy and permit processes for both California and Idaho. As the project continues over the next four years, we see expansion in including additional species in the study and factoring changes in local climate to the behaviors of the target species. It has been a pleasure to work with both Idaho State University and WMSC, and we look forward to continuing over the next four years.
