Aquaculture America 2021

August 11 - 14, 2021

San Antonio, Texas

Add To Calendar 14/08/2021 09:30:0014/08/2021 09:50:00America/ChicagoAquaculture America 2021SOME ASPECTS OF THE REPRODUCTIVE BIOLOGY OF LIMBAUGH’S DAMSELFISH Chromis limbaughi, A POMACENTRID UNDER SPECIAL PROTECTION STATUSRoom 16The World Aquaculture Societyjohnc@was.orgfalseanrl65yqlzh3g1q0dme13067DD/MM/YYYY

SOME ASPECTS OF THE REPRODUCTIVE BIOLOGY OF LIMBAUGH’S DAMSELFISH Chromis limbaughi, A POMACENTRID UNDER SPECIAL PROTECTION STATUS

Martin Perez-Velazquez*, Mayra L. González-Félix, and Hugo Cañedo-Orihuela
 
Universidad de Sonora, Departamento de Investigaciones Científicas y Tecnológicas, Edificio 7-G, Blvd. Luis Donaldo Colosio s/n, e/Sahuaripa y Reforma. Col. Centro, C.P. 83000, Hermosillo, Sonora, Mexico. martin.perez@unison.mx
 

Limbaugh's damselfish, Chromis limbaughi, a member of the family Pomacentridae, is an ornamental fish endemic to the Gulf of California in Mexico. It is a beautifully colored fish, especially during the juvenile stages. The head and the anterior two thirds of the body are iridescent blue, and bright yellow in the posterior part of the body, including the dorsal, anal, and caudal fins. Limbaugh's damselfish is a relatively small-sized fish (10 cm maximum standard length), and unlike many damselfishes, it is relatively peaceful, which makes it compatible with many others fish species in the community tank, which are sought-after traits by saltwater aquarium hobbyists. For these reasons, C. limbaughi is one of the most exploited species for the aquarium trade in the Gulf of California. Regrettably, commercial trade of C. limbaughi is based solely on wild-caught specimens. Due to its endemism, conservation concerns have arisen, which prompted the Mexican government to place C. limbaughi in the list of ornamental fishes with special protection status for wildlife conservation NOM-059-SEMARNAT-2001. However, legal, small-scale fishing for C. limbaughi is still ongoing, not without suspicion that this species is being overexploited, because catch reporting is not appropriately enforced.

Because recovery from fisheries exploitation is a very slow process, captive breeding techniques developed for aquaculture are one viable option to mass produce fish seedstock, which would not only ensure a steady supply of captive-bred fish to meet the demand for marine ornamentals, but also it would alleviate fishing pressure and support stock enhancement of threatened species.

Thus, as a first step towards achieving the goal of reproducing C. limbaughi in captivity, this project investigated some aspects of its reproductive biology. After obtaining a fish collection permit for scientific purposes (Permit No. SGPA/DGVS/06436/17) from the Mexican Agency for the Environment and Natural Resources, we carried out seasonal fish samplings at San Esteban Island, Gulf of California, Mexico. Fish were caught by SCUBA diving using hand dip nets. After being euthanized with an overdose of MS-222, fish were individually weighed, measured, and dissected to determine the body indices, such as condition factor and gonadosomatic index. Each gonad was divided into two parts, one was used for the histological evaluation of the gonad developmental stage, and the other for the determination of the proximate composition and the fatty acid profile. With this information, reproductive biology parameters were determined, such as male to female ratio, length of the reproductive season, and size at first sexual maturity, among others. It is expected that information obtained from the fatty acid profiles of the gonads will provide insight into broodstock nutritional requirements, particularly for lipid and prominent fatty acids. Not less importantly, reliable information of actual field water quality conditions, under which maturation of this species takes place, was gathered in the present study, which will hopefully prove useful for the management of C. limbaughi broodstock in captivity.