Influence of larval and juvenile life history on age at first maturity in two tropical amphidromous fish species

Abstract

This study investigates how age at first maturity of two tropical amphidromous species Sicyopterus lagocephalus (Pallas, 1770) and Cotylopus acutipinnis (Guichenot, 1863) varies in relation to their larval and juvenile life history. Reproductive stage was estimated based on histological observation of ovaries of more than 200 females of each species caught monthly over 1 year. The age of fish was estimated by interpreting the daily increments deposited on otoliths during the oceanic larval phase, and the juvenile phase in the river. The age at first maturity was approximately 9 months for S. lagocephalus and 7 months for C. acutipinnis, corresponding to approximately 70–130 and 90–130 days after they returned to freshwater respectively. For both species, the time spent in freshwater before maturity was significantly influenced by the duration of the pelagic larval stage at sea (PLD) and the season of return in freshwater. Individuals with a long PLD, or returning in freshwater during the warmer season, maturated faster once in freshwater. This reproductive advantage may minimise the risk of extirpation due to catastrophic events at each generation and thus probably benefits amphidromous species living in very unpredictable tropical rivers.

Aquaculture as a tool to support goby‐fry fishery? Current knowledge on biology and ecology of the red‐tailed goby Sicyopterus lagocephalus

“…The females are not mature at sizes below 41 mm (Teichert et al, 2014b). In the field, Lagarde et al (2020b) found the age at first maturity is approximately 9 months for S. lagocephalus, i.e. 90-130 days after they returned to freshwater, but varied depending on the duration of pelagic larval life and the season of recruitment.…”

“…In freshwater, for a few days, the post-larvae can keep a pelagic swimming and a herd behaviour with small schools of 10-100 individuals (Hoareau, 2005;Keith et al, 2015). Metamorphosis into juveniles occurs in freshwater (Keith et al, 2012;Taillebois et al, 2011), and fish become sexually mature after 90-130 days in rivers (Lagarde et al, 2020b). The red-tailed goby life expectancy in freshwater remained unknown but was estimated at 2 years (Artzrouni et al, 2014) by comparison with another similar species, S. stimpsoni (Blob et al, 2010).…”