Hello, tweets.

The Monk Parakeet thread is an interesting one, and people have
touched on some very important issues. The world has changed
immensely because of us, and its pristine nature has been severely
compromised. We have to admit and accept that it's not what it used
to be, at least over a large part of it. Certainly anywhere that
birders go regularly (or Yacolt, where we don't go regularly) would
have to be included in the "much altered" part.

I read a sobering article not long ago, a preprint of an article that
was to appear in Science (so I don't know which volume, but it should
be findable). It was titled Domesticated Nature: shaping landscapes
and ecosystems for human welfare, and was written by four people very
much concerned with conservation biology: Peter Kareiva, Sean Watts,
Robert McDonald, and Tim Boucher. Peter Kareiva works for The Nature
Conservancy.

Here is the abstract of the article:

"Like all species, humans have exercised their impulse to perpetuate
and propagate themselves. In doing so, we have domesticated
landscapes and ecosystems in ways that enhance our food supplies,
reduce exposure to predators and natural dangers, and promote
commerce. On average, the net benefits to humankind of domesticated
nature have been positive. We have of course made mistakes, causing
unforeseen changes in ecosystem attributes, while leaving few if any
truly wild places on Earth. Going into the future, scientists can
help humanity to domesticate nature more wisely by quantifying the
tradeoffs among ecosystem services, such as how increasing the
provision of one sesrvice may decrease ecosystem resilience and the
provision of other services."

The authors presented this as a realistic assessment of the world in
which we live, its potential future, and how we might think about
influencing that future in the wisest ways, as our presence (short of
our extinction while leaving the rest of the world intact) is a
given. Not only our presence but our continued population growth and
the all-too-understandable desire for a higher standard of living on
the part of all of us seem to be givens as well. All of these will
continue to domesticate nature at a rapid rate.

This is high-level scientific speculation, but one not-so-small part
of it is what nature will look like around each of us as she becomes
ever more domesticated. I look out in my yard, and eastern gray
squirrels are almost always part of the view. One part of my brain
thinks "damned invasive critters, look what we're doing to the
world." Another part thinks "it's nice to see a wild mammal (as
opposed to a dog or cat) in the yard." Then I think "in 100 years,
people who love nature/wildlife are going to be soooo thankful for
eastern gray squirrels and raccoons and, yes, probably house sparrows
and starlings." The world may some day be a place of Eurasian
Collared-Doves and Monk Parakeets and gray squirrels and raccoons,
survivors in the Domesticated Landscape, and we might at least spend
some time thinking about whether we really want to eradicate them
from our own neighborhood. The grouse and goshawks and bears and
martens aren't coming back to Seattle, so let's make sure the species
that are happy to live here remain happy. If we extirpated gray
squirrels and starlings, I doubt if any native species would appear
to take their places.

I have always been adamantly opposed to the introduction of species
anywhere in the world, just as a matter of philosophy, and I know a
lot about the terrible outcomes of such introductions, from predatory
fishes in lakes through mongooses onto islands to weedy plants into
shrub-steppe ecosystems. But it is interesting that a review article
published some years ago (sorry, can't recall the reference) on bird
introductions all around the world found very few instances of an
introduced bird species doing serious damage either to other bird
species or the local ecosystem. A lot of these birds are parrots,
pigeons, and partridges, and for the most part they seem pretty
benign and are usually most successful in environments that have been
much altered already. It is indeed ironic when the only harm these
introduced species do is to human endeavors!

The preface of Volume 10 of Handbook of the Birds of the World is a
recent account of introduced birds, their ecology and effects. It
will include the reference I mentioned above. For those of you who
don't know this series, I consider it the best set of bird books that
have ever been produced. They are expensive but worth every penny of
the cost.
-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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