CANADIAN CONFERENCE FOR FISHERIES RESEARCH
(CCFFR)
THE J.C. STEVENSON MEMORIAL LECTURE
This is a prestigious lectureship instituted in memory of Cam
Stevenson, the long-time Editor of the
Canadian Journal of Fisheries and Aquatic Sciences (CJFAS), and is
conferred
upon a young, energetic and creative researcher at the cutting edge of an
aquatic discipline. Each year a Lecturer is selected by the Journal's
Editorial Board from a widely solicited list of North American Candidates.
The Lecturer delivers a stimulating presentation of their work as the
keynote address in the opening session of the Annual CCFFR meeting. A
written version of the presentation is normally published as the lead
article in the January issue of CJFAS or sometime soon thereafter.
The 2000 Stevenson Lecturer is:
Dr. Daniel Boisclair
University of Montreal
A multi-scale approach to fish habitat modeling
Models that predict the effect of changes of environmental conditions on
fish communities focus on variables integrated over time and space (total
fish yield or production, average phosphorus concentration, mean depth,
degree×days). These models reveal general rules on how ecosystems work.
However, perturbations do not affect all parts of an ecosystem equally,
and all parts of an ecosystem do not equally contribute to maintain fish
communities. In the context of the increasing pressure to use natural
resources and to modify habitats, procedures to identify areas of key
importance for fish communities must be developed. Temporal and spatial
scales at which fish and habitats should be studied may be obtained by a
better description of fish distribution. Once these scales are
identified, ecosystems may be represented as a 3D mosaic of
micro-habitats defined using temporal and spatial scales relevant to
fish. The ecological value of each micro-habitat may be defined by its
potential for reproduction, survival, and growth. Bioenergetic models may
be a valid framework to assign values of 'potential for growth' to
micro-habitats because they can function at various temporal and spatial
scales. While objectives are simple to set, making models operational is not.