Site Fidelity, Home Range, and Tidal Movements of White Perch during the Summer in Two Small Tributaries of the York River, Virginia

Abstract

The white perch Morone americana is one of the most common species residing in the brackish tributaries of Chesapeake Bay. White perch make long-distance movements during spring spawning events and find thermal refuge in the winter; however, little is known about their movements in the summer. This study tracked 16 white perch that were implanted with acoustic tags during the summer in two small tributaries of the York River, Virginia. Site fidelity, tidal interactions, and habitat effects were investigated with the program ArcView. If site fidelity existed, a home range and utilization distribution (frequently used locations) were calculated. Most of the tagged fish exhibited site fidelity; for those that did, home ranges averaged 0.11 km². White perch only frequented a small portion of their home range, as depicted by utilization distributions equal to 10% or less of the home range. White perch exhibiting site fidelity displayed one of two different behavioral patterns based upon the surrounding habitat. White perch associated with a marsh habitat used two core areas of activity. The fish were located during high tide upon the flooded marsh and shallow creeks, possibly to forage, and in the relatively deep main channels during low tide, thus avoiding stranding and avian predators. In contrast, white perch associated with submerged structures had only one core area of activity, typically remaining around the one location for the duration of the tag's battery life. The relatively small home range of white perch makes this species vulnerable to local stressors and habitat degradation.