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Books at Duke; Re: dealing with exotics



Hi C-birders,

Was inside Duke's Bryan Center today instead of outside. The Gothic
Bookshop had two greatly discounted bird books on their outside racks.
First, "The Birder's Handbook" by Steve Kress, marked on the hardcover as
$25 but priced by the Gothic at $10. Tips on selecting optics,
photography, observing bird behavior, lots more inside. Secondly,
"Chickadees, Tits, Nuthatches and Treecreepers" by Simon Harrap,
comprehensive guide to those birds and their relatives, identification,
distribution, behavior, habitats, etc. Listed at ABA Sales at $60, selling
at the Gothic for half that! This is on Science Drive on the Duke West
Campus; buy them quick before I relent and buy them myself...

Florida Keys are getting some excitement, with a Zenaida Dove on Key Largo
(along with one of the Western Spindales), and a Yellow-faced Grassquit on
Loggerhead Key in the Dry Tortugas (accessible only by private boat). Few
vagrants of note between there and Massachusetts, where the Eurasian
Kestrel is still being seen, and a Bar-tailed Godwit has shown up on
Martha's Vineyard.

On Tue, 7 May 2002, Harrold, Eric S wrote:
>
>  Great idea Mike, but logistically, well it might be a bit much to pull off.
> As a biologist, getting rid of exotics is a fundamentally sound notion. I'm
> afraid we'd need participation from a vast majority of our society, most of
> whom are ecologically ignorant on all fronts. About the most constructive
> action I can't think of with Starlings and House Sparrows is to pick them
> off one by one with a pellet rifle as they menace your feeder or nest boxes
> and pretend that you've just eliminated another conservative right-wing
> militant with a big-business political agenda.

As a third biologist (Mike is one too), I'd have to bring up that killing
adults is generally an inefficient way to control adult animal
populations. The deaths of the adults usually decreases intraspecific
competition, territoriality, etc. and so increases the breeding success of
the remaining critters. Much more expensive, but generally more effective
in the long run, is sterilization: the exotics can't reproduce, but still
defend territories, consume resources, monopolize mates and negate *their*
reproductive success too, and make it difficult for new youngsters to
survive. The sterilized adults eventually die of old age or predation,
after having depressed their species' population for years.

Unfortunately, most of the most severely ecologically damaging exotic
species in the Carolinas are plants (Ligustrum/Privet, English Ivy,
Mahonia/Oregon Grape, Japanese Honeysuckle, Chinese Wisteria, Kudzu, White
Mulberry, Eleagnus/Russian- and Autumn-Olives, bamboo, etc.). As far as I
know, nobody's come up with a method to sterilize plants yet, outside of
the rare seed-eating insect or fungus, all we can do is keep weeding them
out until the right insect comes along.

Good birding,

Josh


Joshua S. Rose
Duke University
Department of Biology (Zoology, R.I.P.)

jsr6@duke.edu
http://www.duke.edu/~jsr6/