Captive Breeding of the Critically Endangered Wild Betta burdigala Under Laboratory Conditions

Abstract

Betta burdigala, a species endemic to Bangka Island and listed as Critically Endangered by the International Union for Conservation of Nature (IUCN), has been successfully bred under controlled laboratory conditions. This study provides detailed insights into its captive breeding, highlighting key parameters essential for ex situ conservation and the development of sustainable breeding protocols. The research involved breeding trials, bubble nest formation observations, hatching rate (HR) assessments, larval monitoring, initial feeding evaluations, fry rearing, and survival rate (SR) analysis. On average, females measuring 2.45 ± 0.07cm in total length produced 61.50 ± 4.95 eggs, from which 60.00 ± 4.24 larvae hatched, resulting in a high HR of 97.00 ± 1.41%. Larval development and yolk sac absorption were tracked from 0 to 4 days post-hatching, after which larvae were fed Moina sp. for up to 50 days. In the initial trial, 30.50 ± 3.54 larvae survived to day 50, yielding an SR of 50.50 ± 9.19%. These findings offer valuable baseline data for the conservation and early life stage management of B. burdigala, supporting future recovery programs. Further research is recommended to examine the long-term impacts of captivity on behavior, physiology, and phenotypic traits.