Silver Redhorse - Abstract

Abstract

The Silver Redhorse (Moxostoma anisurum) is slowing becoming more and more rare in the rivers and lakes across the southeast. It is considered threatened in the state of Arkansas by the Nature Conservancy. The reasons for their decline vary from year to year, but one theory from 2003 stands out from the rest. Weyers, Jennings, and Freeman conclude that the high-velocity, pulsed water flow that makes its way downstream from hydropower-generating dams has been the leading reason for decline in the species. With these problems happening primarily in the south, the Silver Redhorse (Moxostoma anisurum) seems to thrive better in the far north. Comtois claims that in Quebec, Canada the Silver Redhorse is abundant in what they call V-males, as they outnumber the females considerably. For every female on the spawning bed, there is a minimum of 2 males that are used to successfully reproduce. These observations which were recorded in 2004 were greatly useful to the understanding of reproduction the Silver Redhorse. But before these findinds surfaced, it was an electrophoretic study of the Silver Redhorse that gave the scientific world an idea of the species reproductive status. In 1983 Morgan, Smith, and Stauffer concluded that the protein composition of the species larvae had a direct comparative link to the gradient electrophoresis used to separate the larvae. One year previous, in 1982, 2 new species (Pseudomurraytrema milleri) and (Pellucidhaptor moxostomi) are recorded to be a branch or sub-species of the Silver Redhorse. Mergo and White state that the gills of both the Pseudomurraytrema milleri and the Pellucidhaptor moxostomi are directly connected to those of the Silver Redhorse (Moxostoma anisurum).