Reproductive biology of female cardinalfish, Epigonus crassicaudus de Buen, 1959

Abstract

Summary The cardinalfish (Epigonus crassicaudus) is a long‐lived and endemic deep‐water fish inhabiting the central and southern coast off Chile. Knowledge about basic biological attributes including maturity aspects is fragmentary in this species. The historical and comprehensive data available are applied to provide a detailed study of the reproductive biology of the female cardinalfish. The gonadosomatic index was computed from 5110 female gonads collected by onboard scientific observers between October 2000 and December 2012. A total of 1467 females gonads collected between March 2007 and December 2009 were subjected to histological analysis of maturation upon which a maturity ogive was estimated. The ovarian development of this specie is asynchronous, characterized by a continuous reproductive cycle in which reproductive activity is found throughout the year with a maximum during the austral autumn and summer (between May and June). Length at 50% maturity was estimated in 23.2 cm of fork length (95% CI: 21.7–23.9 cm). The results presented here are compared with previous sparse estimates available for this species.

Reproductive traits and natural mortality of the cardinalfish Epigonus crassicaudus: crucial information for stock assessment and sustainable management measures

“…If L∞ = 34 cm FL, indicated by Moyano et al (2018), is considered, the value for this relationship in E. crassicaudus would be 0.65-0.67. The results for L50% confirmed those reported by Flores et al (2015), who used the histologic methodology to estimate this value, could validate the macroscopic approach in fish maturity studies when funding is scarce, or a quick estimation is needed.…”

“…In the present study, after 28 cm FL, some portion of females continued being assigned to the immature fraction of the population, which is frequent in macroscopic scales of maturity because mature adult females in resting, could be mistakenly classified as immature due to its poor ovarian development (Hunter & Macewicz, 2003;Murua & Saborido-Rey, 2003;Tomkiewicz et al, 2003;Brown-Peterson et al, 2011). Despite this apparent bias in the allocation of maturity states, L50% reached 22.3 cm FL close to the value estimated by Flores et al (2015), who reported an L50% of 23.2 cm FL for samples coming from a similar study area. Compared with L50% in technical reports, our results were close to 24.3 cm FL estimated by Gálvez et al (2013) and smaller than 32.1 cm FL, estimated by Cubillos et al (2009), who considers smaller samples and a more restricted study area.…”

“…These results are partially coincident with the unique study published before in the reproductive biology of Epigonus crassicaudus. Flores et al (2015) showed the occurrence of permanent vitellogenesis through the year, although identified through GSI, a reproductive peak between May and June. Hence, the results of the current study confirm the spawning season for this species to be concentrated in austral fall off the Chilean coast.…”

“…In studies related to the maturity process in size or age, it is common to find 100% of mature individuals after a certain length or age. To E. crassicaudus, Flores et al (2015), based on histological analysis of ovaries, determined 100% of mature females occurred about 28 cm FL. In the present study, after 28 cm FL, some portion of females continued being assigned to the immature fraction of the population, which is frequent in macroscopic scales of maturity because mature adult females in resting, could be mistakenly classified as immature due to its poor ovarian development (Hunter & Macewicz, 2003;Murua & Saborido-Rey, 2003;Tomkiewicz et al, 2003;Brown-Peterson et al, 2011).…”

“…Regarding its biology, some studies addressing the food and trophic levels of this species have been reported (e.g., Arancibia & Meléndez, 1987;Neira & Arancibia, 2004;Leal et al, 2009;Sepúlveda et al, 2018). Also, the annual reproductive cycle and maturity in length to females was reported by Flores et al (2015). However, to date, there not published information on natural mortality (M) for E. crassicaudus; nevertheless, technical reports (Cubillos et al, 2009;Tascheri & Flores, 2013) have suggested low values to this parameter due to low growth rates and a potential long-life span.…”