Allee and patch size

[Kondla, Norbert FOR:EX]

Maine, where after
years of public debate a law was passed requiring clearcutting to be limited
to relatively small patches with equally small patches in between left
unlogged. There is now evidence that the bird species mix has been
substantially affected by the increase in edge. Some have actually backed
the
idea of clearcutting larger areas but also leaving larger uncut areas, with
the total logged area not changing. However, all parties are tired after the
last debate and there has been reluctance to reopen a contentious issue
(this
information is 2-3 years old and may have changed-- anyone?)."
 
Logging and how to do it "right" continues to be subject to differing and
strongly held views.  Like most complicated matters that deal with
ecosystems over large landscapes; there is no single "right" approach.
Clearcutting only in small patchs with only small leave areas is guaranteed
to fragment the ecosystem into oblivion (or at least a substantially altered
state) and is counter to the results of all research that I am aware of on
this issue of habitat connectivity in forested ecosystems.  Risk management
to reduce the risk of accidently losing an organism over a landscape points
to keeping a variety of patch sizes in the landscape, unless of course one
is dealing with a forested ecosystem where the natural disturbance regime is
clearly confined to small structureless openings.
 
 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Norbert Kondla  P.Biol., RPBio.
Forest Ecosystem Specialist, Ministry of Environment
845 Columbia Avenue, Castlegar, British Columbia V1N 1H3
Phone 250-365-8610
Mailto:Norbert.Kondla at gems3.gov.bc.ca
http://www.env.gov.bc.ca
 
 
 
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