DIEL PERIODICITY OF ACTIVITY AND VERTICAL DISTRIBUTION OF PERCH (PERCA FLAVESCENS MITCHILL) UNDER THE ICE.

Abstract

An echo sounder was utilized from early January to midMarch to collect information on the daily activity patterns and depth distributions of yellow perch in Lake Mendota, Wisconsin, a highly productive eutrophic lake with winter characteristics very similar to other eutrophic lakes of temperate regions. The ice reaches a thickness of at least 20 inch (50 cm) and the lake usually remains icecovered for an average of 114 days. Recordings of 24 hours duration were made throughout the winter at selected sites. It was learned from these observations that the yellow perch are active primarily during daylight hours with peak periods occurring in mid-morning and early afternoon. Usually the afternoon peak is of smaller magnitude than the morning peak. The peaks are in large part owing to perch schools which are active at those times. There was a marked difference in the number of perch recorded at shallow stations as compared to deep stations. The number of fish recorded was always much larger at the deep (over 50 feet) stations. Perch appear to remain concentrated in the deeper portions of the lake throughout the duration of ice cover. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 23, 1965
Accession Number
AD0619974

Entities

People

  • A. D. Hasler
  • G. L. Hergenrader

Tags

DTIC Thesaurus Topics

  • Daylight
  • Fish
  • Geographic Regions
  • Observation
  • Periodic Variations
  • Regions
  • Sonar
  • Temperate Regions
  • Thickness
  • Wisconsin

Fields of Study

  • Environmental science

Readers

  • Aquatic Ecology
  • Polar and Arctic Studies
  • Space/Atmospheric Physics.