"Spawning clasps and gamete deposition in pebble nest-building minnows " by Mark Henry Sabaj

Date of Award

1992

Document Type

Thesis

Degree Name

Master of Science

Department

Biology

Abstract

Spawning in five species of North American cyprinid minnows (Rhinichthys a. atratulus, Exog/ossum laurae, Semotilus atromaculatus, Nocomis leptocephalus, and N. micropogon ) are analyzed on videotape filmed in Virginia and Maryland streams. Behaviors are chronologically resolved into a sequence of categories (Interim, Approach, Alignment, Run, Clasp and Dissociation) exemplary of a successful spawn as defined by the clasp. The categories are used to describe spawning behaviors in each species. In all species studied, a successful spawn is a female initiated event effecting the clasping response of a male.

The species-specific pattern of male-female interactions not only reflects the coordination of the spawning clasp, but the architecture of the spawning substrate. In the pebble nest-building cyprinids (i. e., species of Exoglossum, Semotilus and Nocomis ) a successful spawn is the end result of a topographically fixed sequence of behaviors that place the clasped pair over a discrete area of the nest specifically composed for gamete deposition and retention.

Share

COinS