Poecilia sphenops is a native species recently
reported to be widespread and widely distributed in the Balsas basin and the
Amacuzac River in Morelos (Mexico). This research studied some aspects of
Poecilia sphenops reproductive biology from the Emiliano Zapata reservoir in
Central Mexico. Specimens were collected from January to December 2006 using a
20 m-long die with a 5 mm mesh scale. A total of 581 specimens were collected:
407 females (70.0%), 83 males (14.3%) and 91 non-differentiated sex individuals
(15.7 percent ). The fish had a total length of between 20 and 96 mm and a body
weight of between 0.01 and 13.07 g. The ratio of female to male sex (4.9:1)
substantially deviated from the unit (χ2= 214.2, p<0.05). Monthly
differences in gonadosomatic (GSI) and hepatosomatic (HSI) indexes and stages
of ovarian growth showed that the spawning season of P. sphenops coincided with
the rainy season between July and October. In February, another reproduction peak was
recorded. For males and females, the largest length recorded was 96 mm and 83
mm, respectively. Some of the variables that could restrict fish reproduction
in the reservoir were temperature, food availability and efficiency. The
reproductive knowledge obtained in this P. sphenops analysis would make it
possible to control fisheries. No concrete steps to control this resource have
been introduced to date. In exploitation, the size at first maturity should be
considered.
Author(s) Details
Gómez-Márquez, José Luis
Laboratorio
de Limnología, F.E.S. Zaragoza, U.N.A.M., C.P. 09230 Iztapalapa, Ciudad de
México, Mexico.
Peña-Mendoza, Bertha
Laboratorio
de Limnología, F.E.S. Zaragoza, U.N.A.M., C.P. 09230 Iztapalapa, Ciudad de
México, Mexico.
Guzmán-Santiago, José Luis
Laboratorio de Limnología, F.E.S. Zaragoza, U.N.A.M., C.P. 09230
Iztapalapa, Ciudad de México, Mexico.
View Book :- https://bp.bookpi.org/index.php/bpi/catalog/book/343
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