Date of Award

11-2017

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Ocean Engineering and Marine Sciences

First Advisor

Jonathan Shenker

Second Advisor

Aaron Adams

Third Advisor

Ralph Turingan

Fourth Advisor

Jorge Angulo Valdes

Abstract

Bonefish (Albula spp.) are a prized sportfish among avid anglers worldwide. Two morphologically indistinguishable species of bonefish (Albula vulpes and Albula goreensis) exist in the circumtropical waters of the western Atlantic. A. vulpes grows faster and reaches larger sizes in the Florida Keys than in the Bahamas and other insular regions, but the mechanisms driving this variation have not been identified. Cuba supports large populations of bonefish, but their age, growth rate, and reproductive biology has not previously been examined. I obtained specimens from fish markets and local research staff in 3 regions around the periphery of Cuba from November 2016 to January 2017. Sagittal otoliths and fin clips were collected from each fish, and sex was determined by visual examination of gonads. Fin clips were sent to the Genetics Laboratory at the Florida Fish and Wildlife Research Institute for identification. Otoliths were aged by embedding, sectioning, and examining thin sections. A total of 218 bonefish were sampled, with a size range of 187-530mm FL. Genetic testing indicated that 134 were A. vulpes, 59 were A. goreensis, and 7 were hybrids. The oldest fish collected were 8 and 9 years old for A. vulpes and A. goreensis respectively. Both species of bonefish displayed gonadal development indicating the preparation to spawn in the month of November 2016. Growth of A. vulpes was rapid until the age of 5 years then slowed, with females reaching larger sizes than males. The fewer specimens for A. goreensis prevented calculation of sex-specific growth curves. Predicted fork length at age values were greater at all ages for A. vulpes compared to A. goreensis. All bonefish collected above the size of 231mm FL with exception of one fish were found to be reproductively mature. Bonefish were observed to be reproductively mature at the age of 1 year, much smaller and younger than observed in previous studies. The insight of varying growth patterns between A. vulpes and cryptic species allows for better management of the species, and further distinguishes differences in the biology of A. vulpes and A. goreensis.

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