[Tweeters] White-collared Seedeaters ... and other spp.

Jim Greaves lbviman at blackfoot.net
Tue Mar 31 14:53:49 PDT 2009


At Tweeters, "Messick, Katie" <Katie.Messick at kingcounty.gov>
wrote comments regarding Arundo donax and its adverse impacts on
several species. I do not think the science is "done" on that score;
perhaps the politics is. And I do not endorse its retention. That said...

It is NOT true that Bell's vireo and Willow flycatcher do not use
Arundo donax (for nest cover as well as nest support), as I have
found a small percentage of LBV nests in A.donax during a decade-plus
of monitoring a sizable population along Santa Clara River in Ventura
and LA counties in California. Additionally, the first successful
SWFL nest in Ventura county in many decades (of 3 nests found during
2000, after it was considered extirpated as a breeder in the county)
was from a nest suspended on A.donax at the same time a nest on A.
donax was being monitored in San Diego County. And, the next year
(2001), while one pair in vicinity of that 2000 Ventura nest raised 4
young from nettles, simultaneously a female (probably the 2000
female) raised several nestlings from A.donax at the exact spot as
the prior year's nest (which had been collected and donated to Santa
Barbara MNH collection). So, of 3 nests known to fledge young SWFL in
2000 and 2001, 2 were from Arundo-supported nests, 1 from native [2
prior nests in 2000 failed, cowbird dump and infertility, 1 in
nettles, and 1 on Rubus ursinus and Scirpus] -- this in an area
replete with native vegetation that supported/supports 30-plus pairs
of LBV within a mile of the site [Fillmore Fish Hatchery]; in 2007, a
SWFL built a nest on Arundo just off the hatchery, and was later seen
feeding young within 30 meters of that nest (the nest was not
re-found on subsequent visits, so not certain if it was the one from
which the young emerged). Anomalous, perhaps, but sufficient, along
with references of nests I've found of other species in, on, or
surrounded by Arundo, to warrant caution. It is an important element
where found, regardless of its obnoxiousness:
http://blackfoot.net/~larkwick/Aliens_nests_1.html
This is by NO means an endorsement of retaining the stuff, but until
it is replaced with native vegetations (plural) of sufficient density
and cover to provide what is taken when it is removed, caution should
be used in the removal of ANY "invasive" or alien plant species,
regardless of motivation or "correctness" of the chosen solution --
Jim Greaves, Montana



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