Harvest management - Ecological Applications: Toward a Sustainable World - page 212

A socioeconomic view of harvest management
One shortcoming of a purely ecological approach to harvest management is failure
to recognize that when harvesting is a business enterprise, the monetary value of
the harvest must be set against the costs of obtaining it. Economic models have been
developed to estimate the economically optimum yield (EOY), which is invariably
less than the MSY. 'Social' factors also enter the sustainable harvesting equation -
because of the need to factor human nature (poaching, etc.) into harvest manage-
ment procedures and because political realities sometimes work against taking
ecological advice.

The fi nal word

Elena, the Guatemalan forester, was frankly amused to hear about the effect of
hunting on the size of trophy animals. ' We laughed when I told my friends about how
hunting for the big animals made them evolve to be smaller - the hunted ones strike back!
My parents said this explained why the fi sh market seems to sell much smaller fi sh than
they remember from their younger days. Thank goodness the same thing does not happen
with our forest trees. '
Check back over Chapters 5, 6 and 7 to review the importance of understanding
evolutionary theory when managing endangered species, pests and harvests. What
mistakes will managers make if they do not believe in evolution?

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