[Tweeters] RE: Spotted Owls ( and Barred Owls)

Rob Sandelin floriferous at msn.com
Mon Dec 13 08:50:26 PST 2004


The competition between Barred and Spotties raising some interesting
questions about endangered species. Owls have a function in the forest
ecosystem. They move nutrients around and affect populations of their prey.
Clearly, Barred owls seem to be better adapted to the conditions which exist
in the current world, thus  their populations are expanding, while spotties
seem to be poorly adapted to the conditions and are declining. It appears on
the surface, and I am no expert, that Barred owls can occupy similar niches
in the environment, eat the same prey,  and seem to be more succesfull
nesting in the current multi-abuse forest environment. So one owl, which is
better adapted, is replacing another.  It seems that Barred owls could
easily occupy the niche in the forest vacated by Spotties without any large
scale effects on the ecosystem, since barred fills the niche of Spotties as
far as we know. There appears to be cases where even in large old growth
tracts, barred are outcompeting Spotties.  So, in a pretend world, in which
all the old growth habitat existed intact, would barred owls take over from
Spotties over time? If so, isn't this a natural progression?

Or to put this in a biological question, in 50 years, if Barred owls replace
Spotties, what measurable affect would it have on the function of the
forest? 

Or, is there something a Spotted Owl does in the forest which a Barred owl
does not do?

Of course, given what little we can really know about much of how things
work, we will never know. 

Rob Sandelin
Naturalist, writer, teacher

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.805 / Virus Database: 547 - Release Date: 12/3/2004
 



More information about the Tweeters mailing list