Influence of Physical Processes on the Early Life History Stages of Walleye (Stizostedion vitreum) in Western Lake Erie

Influence of Physical Processes on the Early Life History Stages of Walleye (Stizostedion vitreum) in Western Lake Erie

Edward F. Roseman, William W. Taylor, Daniel B. Hayes, Robert C. Haas, David H. Davies, and Scudder D. Mackey

Influence of Physical Processes on the Early Life History Stages of Walleye (Stizostedion vitreum) in Western Lake ErieThis is part of Ecosystem Approaches for Fisheries Management
Format Price  
PDF download [208.5 KB] Free Add to Cart
  Bypass cart and download

Description

Physical processes create the environmental settings in which biological processes occur. Therefore, physical processes can have strong effects on fish populations, especially during vulnerable early life history stages. Much of the variability in recruitment of Lake Erie walleye is thought to be caused by variable survival during the egg and larval stages. Recent research on Lake Erie walleye indicates that density-independent physical processes directly affect the vital rates of these early life history stages. In western Lake Erie, large scale storm events in spring were related to high mortality of walleye eggs and larvae on reefs and subsequently produced poor recruitment. In addition, variability in environmental conditions (e.g., water warming rate) prolongs life history stage durations over which high mortality rates operate. Slower water warming rates in western Lake Erie prolonged walleye egg incubation and pelagic larval stages extending the period of vulnerability to disease and predation for these early life history stages and negatively impact year-class strength. Physical processes rarely function independently but facilitate the underlying ecological mechanisms
that drive fish population dynamics. Therefore, it is essential to
examine physical processes in relation to biological processes in order to gain a more complete understanding of the linkages between them. By doing so, we gain a stronger basis for predicting the response of fish populations to environmental variability.

Item details