Title

Population Structure, Reproduction And Laboratory Behavior Of The Introduced Belonesox Belizanus (Poeciliidae) In Florida

Keywords

Brood size; Development; Exotic species; Feeding; Gestation period; Livebearer; Maturation; Neonate; Pike killifish; Sex ratio; Viviparity

Abstract

The pike killifish, Belonesox belizanus, is native to Mexico and Central America and was introduced into Dade County, Florida in 1957. This study reports on the structure and reproduction of the Florida population and compares the species with other members of the family Poeciliidae. The mean standard length (SL) of mature females was about 103 mm. Most females larger than 75 mm SL contained yolked ova, fertilized eggs, or embryos. Mature males averaged about 72 mm SL, and most males larger than 55 mm SL were mature. The sex ratio was significantly skewed in favor of females among adults, but it did not differ significantly from 1:1 among immature fish. Average brood size was about 99, and there was a significant positive correlation of brood size with size of the parent female. There was no evidence of superfetation. Sizes and weights of embryos and neonates were the largest reported for the family. There was a significant decrease in mean embryo weight as development proceeded, indicating that developing embryos received little or no nutrient input from the maternal system after fertilization. The average interbrood interval of aquarium-held females was 42 days, and females stored viable sperm at least 47 days. Reproduction continued year round in the field. Laboratory-born neonates were immediately piscivorous and exhibited distinctive behavior associated with filling the swimbladder and with avoiding detection by predators. © 1984 Dr W. Junk Publishers.

Publication Date

2-1-1984

Publication Title

Environmental Biology of Fishes

Volume

10

Issue

1-2

Number of Pages

89-100

Document Type

Article

Personal Identifier

scopus

DOI Link

https://doi.org/10.1007/BF00001665

Socpus ID

0021576746 (Scopus)

Source API URL

https://api.elsevier.com/content/abstract/scopus_id/0021576746

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