Finally, a coherent discussion of a complex issue that does more than
push emotional buttons on one side or the other.

I generally take the view that, if we can leave it alone rather than try
to engineer the world, that will be the best decision. Clearly there
are times and circumstances when we should not engineer the world to our
specifications. That is appropriate when I argue that continuing
releases of non-indigenous taxa are a bad idea, even though we can't
change past mistakes (think more turkeys and more hatchery salmon as bad
engineering in most circumstances). But when our actions have pushed a
species to the brink of disappearance over a substantial portion of its
range (SPOW), we should carefully evaluate how and when that dreaded (by
me) engineering is needed. SPOW deserve more than a passive society
watching them experience massive reduction in their range (or worse), if
we can do something to halt that trend.

And of course the decisions on these issues should be grounded in the
most comprehensive review of the scientific information available to
us. Scientific information is crucial to making the best decision,
although it is not the only thing relevant to leading us to the right
decision.

Jim Karr



Bob Pearson wrote:
> I have been tracking Spotted and Barred owls in northern Gifford
> Pinchot NF since 1992. I've documented the rapid increase of Barred
> Owl pair sites throughout my area as well as the decline of active
> Spotted Owl pair sites. I'm not ready to give up on Spotted Owls
> yet. Here are some observations based on my experience.
>
> Even though much of what is reported concerning Barred Owls in areas
> with Spotted Owls is doom and gloom, there are Spotted Owls that
> continue to hold territories and reproduce with Barred Owls in the
> vicinity, and there are areas that have more Spotted Owls than Barred
> Owls. In my area, the Spotted Owls that have persisted generally are
> those on the steeper and drier ridge-sides. The areas with the highest
> density of Barred Owls are generally flatter and in valley-bottoms,
> often associated with wetlands. I have Spotted Owls that have been
> adjacent to Barred Owls for more than 10 years, active Spotted Owl
> sites surrounded by Barred Owls, and several areas where there are
> still only Spotted Owls.
>
> Given the rapid increase of Barred Owls and decline of Spotted Owls,
> the conclusion that Barred Owls will completely displace Spotted Owls
> is the "safe" conclusion. But the final result of Barred Owl
> colonization and the impact to Spotted Owls is an unknown. I think it
> is important to fully consider that Spotted Owls were in trouble due
> to habitat loss prior to the widespread distribution of Barred Owls.
> It is also important to consider that the changes we made to the
> landscape that were detrimental to the Spotted Owl were very
> likely favorable to the Barred Owl. Because of this environment we
> have created, you can't really say that it's natural for Barred Owls
> to displace Spotted Owls.
>
> To say that we should let nature take its course is to absolve us from
> responsibility for our actions. It is not a natural progression, it is
> nature responding to our manipulations of the environment. If killing
> Barred Owls to benefit Spotted Owls is "murder," then doing nothing to
> redress our past actions is "murdering" Spotted Owls. It is semantic
> sleight of hand to say that selective removal of Barred Owls is
> murder, while loss of Spotted Owls through inaction is not.
>
> The proposal to selectively remove Barred Owls in the Draft Recovery
> Plan is not intended to extirpate Barred Owls from the range of the
> Spotted Owl, it is to "target key areas for removal of Barred Owls."
> The purpose is to remove Barred Owls from certain areas to see how
> Spotted Owls respond. The results of this action would then be
> assessed for the potential to help recover the Spotted Owl.
>
> The premise is straightforward: Barred Owls appropriate habitat that
> Spotted Owls use for nesting and reproduction, and so that habitat
> becomes unavailable to Spotted Owls. Remove the Barred Owls and the
> habitat then becomes available again for Spotted Owls to use. In
> northern California, a Barred Owl pair was removed from an historical
> Spotted Owl nest site, and the Spotted Owls were back within one week.
>
> When Spotted Owls vacate a site it is unlikely they are killed by
> Barred Owls (not very cost-effective for Barred Owls, as Spotted Owls,
> being nearly equal in size, could do a lot of damage). It is more
> likely that they become "floaters" that roam about without nesting,
> possibly even in the same area as they had been nesting, as seems
> likely in the California example. These are the owls (as well as
> dispersing sub-adults) that would re-colonize areas where Barred Owls
> were removed. Adult Spotted Owls that have occupied a territory are
> proven to be successful, but will eventually die, and this brings with
> it an urgency in time to provide the opportunity for them to
> re-colonize before they do die.
>
> I believe that Spotted Owls, to have the chance to recover, need some
> breathing room from the onslaught of habitat removal compounded by
> Barred Owl incursion. It needs to be considered that a population
> weakened by habitat removal may have a harder time fending off Barred
> Owls than a strong population. The selective removal of Barred Owls
> from key areas would provide local havens where Spotted Owls could
> gain rather than lose ground and, perhaps most importantly, raise
> juveniles to support the population.
>
> Another factor that may be pertinent is colonization dynamics. There
> are indications in British Columbia that the Barred Owl population may
> have peaked and then somewhat declined. The idea to explain this would
> be that prey available to Barred Owls was plentiful at first and
> allowed over-population, but then the population leveled out at a
> lower number due to decreased prey, and would stay at the lower level.
> If this is what happens, then Spotted Owls would be better able to
> contend with Barred Owls at lower numbers. But if Spotted Owls reach a
> critical level of low numbers before this happens, they may not be
> able to recover. Selective control of Barred Owls in key areas could
> be the difference.
>
> Every one of us who lives in a wooden house, uses toilet paper, or
> buys a product with more packaging than product has indirectly
> contributed to habitat loss and attendant loss of wildlife. Every one
> of us who has driven in the forest has directly killed wildlife. As a
> society, we will not stop building, logging or driving, but we can do
> our best to take responsibility and mitigate the effects of our actions.
>
> Barred Owls are here to stay, and I really like Barred Owls, but I'd
> like to give Spotted Owls every opportunity to stick around as well,
> particularly since we have already made it so difficult for them to do so.
>
> Bob Pearson
> Packwood
>
>
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