Assessing Physical Qualities and Fatty Acid Profiles of Early-Stage Bonefish ( Albula Goreensis ) Leptocephalus Larvae Reared in Captivity to Better Understand Early Life History Traits and Inform Conservation Methods

Bonefish are members of one of the oldest extant teleost superorders, Elopomorpha, which also includes eels, tarpons, and ladyfish. All share a common larval stage called the leptocephalus or “glass eel” stage. Though bonefish serve an important role in Caribbean ecosystems and fisheries, little is known about their life history and reproductive process. In order to observe and better describe bonefish spawning characteristics, wild bonefish ( Albula goreensis ) were collected off of Stuart, FL, USA. The group was transported to Harbor Branch Oceanographic Institute and acclimated to captive habitats where they underwent monthly hormonal manipulation to induce spawning. Spawning events occurred on October 4 and 6, 2020. For both spawns, eggs were collected in an egg collector and transferred to Kreisel tanks to hatch. Samples of eggs were collected prior to hatching to determine biometrics such as size, fertilization success, and hatching success. Leptocephalus larvae were collected daily for up to 3 days post-hatch, and biometric data was recorded for a subsample of larvae. Total fatty acids were extracted from egg and larvae samples and analyzed using GC–MS detection methods. Larvae samples showed a general decrease in polyunsaturated fatty acids (PUFAs) coinciding with growth after hatching, supporting the notion that PUFAs are utilized for growth and metabolic processes. This project is part of a multi-year effort to successfully spawn bonefish in captivity and can be utilized as a baseline in future studies intended to inform conservation methods for wild populations.