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ABSTRACT.-
Gonadal condition of the cyprinid stream fish Notropis telescopus (telescope shiner) was monitored from Feb. to Sep. to determine reproductive schedule. The study site was at the southern limit of species range in northeastern Alabama. Notropis species are multiple batch spawners with strong seasonality to gonadal size and condition. The number of maturing oocytes observed in ovaries was at a peak from Apr. to Jul., with strong majorities of oocytes at the most mature stages in Apr., May and Jun. Ripe and fully mature ovaries were found in fish collected in Apr., May and Jun. A pronounced peak in the gonadosomatic index (GSI) was found in Jun. for both males and females. The evidence points to an Alabama spawning season from Apr. to Jul., peaking in the middle of this season.
INTRODUCTION
Cyprinid stream fishes of temperate North America typically spawn in the spring to allow larvae to grow enough to survive their first winter. The details of each species' reproductive effort vary as an important part of its ecological niche. With the high species diversity of cyprinid stream fishes in the southeastern United States there are many variations on the theme of vernal spawning and thus in the ecological niches of these species (Warren et al, 2000).
One such cyprinid is Notropis telescopus (Cope) (telescope shiner), found in the Cumberland and Tennessee river drainages east of the Mississippi River and the White and Black drainages in the Ozarks west of the Mississippi. N. telescopus is a common inhabitant of runs and flowing pools over sand and gravel in creeks and small rivers with clear water. Emier and Starnes (1993) report observations of the species spawning in Tennessee from mid-Apr. through mid-Jun.
The purpose of this study is to determine the schedule of reproduction (sensu Heins and Rabito, 1986) oí Notropis telescopusby examining gonadal condition. Fish were sampled from Feb. through Sep. to observe any patterns of gonadal maturation, maturity and decline. No previous study has addressed the schedule of reproduction for this species. Both males and females in the genus Notropis and closely related genera are known to be multiple spawners, with females producing more eggs than are found in the ovary at any one time (Heins and Clemmer, 1976; Dahle, 2001;...