FECUNDITY OF SCOMBEROMORUS SIERRA (PERCIFORMES: SCOMBRIDAE) IN THE COLOMBIAN PACIFIC

Abstract

Scomberomorus sierra (Pacific sierra) is one of the most important species in the artisanal fishing on
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30 Boletín de Investigaciones Marinas y Costeras • Vol. 46 (1) • 2017
the Colombian Pacific. In order to investigate its reproductive biology, important input for fishery
management, gonadal development was described and partial fecundity and average size of the oocytes
were estimated. Fish samples came from commercial landings on different fishing grounds. Total (TL)
and standard lengths of each fish were measured, as well as the total and gonadal weights. Fecundity
was estimated using a gravimetric method combined with image analysis performed using the open
access software Image J®. 79 fish were collected between November 2013 and April 2014, ranging
from 39.0 to 85.0 cm in TL and weighing between 300 and 2850 g. The allocation of gonadal maturity
was histologically verified, finding 75 females and 4 males. From the measurement of 12084 oocytes, an
average diameter of 0.551 ± 0.024 mm was obtained, while fecundity varied between 52398 and 480803
oocytes per gonad. Microstructurally, four stages of oocyte development (perinuclear, cortical alveoli,
vitellogenic and hydrated) were identified; only one state was observed in males. Mean diameter of the
oocytes in the cortical alveoli, vitellogenesis and hydrated stages were 168.75 ± 3.86 μm, 324.08 ± 5.89
μm and 388.90 ± 8.81 μm, respectively. The relationship between fecundity and morphometric variables
of the fish was significant and positive, evidencing that the largest females are the most fertile. Size at
sexual maturity was preliminary estimated at 58.88 cm TL. The results obtained are inputs from fishery
models with direct applicability to management of S. sierra.