[texbirds] Re: Whooping Crane Counting Changes
- From: Jim Sinclair <jim.sinclair@xxxxxxxxx>
- Date: Fri, 21 Feb 2014 07:28:55 -0600
Lots of "if's" in Phil's reply.
Any time one wishes to challenge a particular scientific method, one must
provide the justification for such challenge. In this particular case, the
rebuttal to the current methods has not included any statistical proof.
Additionally, no justification is provided to support Phil's assertion that
"If Tom's statement of "estimated 254 plus or minus 62 whooping cranes in
the survey area" is correct then the methodology is hopelessly inadequate
for the purpose intended and needs to be immediately reverted." Even if
Tom's assertions are correct (they may be, but I want to see the proof),
Tom's assertions do not support Phil's assertions. No justification is
provided as to why a precise count is required for management purposes.
In the case of the Whooping Cranes on wintering grounds FWS has no ability
to control the movement of the cranes. It can only try to maintain the
viability of the habitat that it either owns outright (refuges) or controls
through conservation agreements. It cannot control the cranes themselves.
There is currently enough preserved habitat acreage to support about 500
cranes, if that habitat remains viable. FWS has been tasked to identify
and preserve enough habitat to support 1000 cranes, but has been given no
funding to acquire any additional habitat by purchase. As cranes continue
to utilize other resources that are not under the influence of FWS, the
habitat monitoring will become increasingly complicated.
I think most of us recognize that the current protected habitat is under
assault, due primarily to water issues. The more the habitat degrades, the
more the cranes are going to have to disperse.
The bottom line is that the challenges facing us in our efforts to protect
the cranes are all related to habitat conservation. And I have seen no
quantified assertion that addressing those challenges is significantly
impacted by the difference in precision of the count between the old method
and the new method.
This discussion about the precision of the count has been going on ever
since Tom retired, and the methods changed. I have yet to see any
quantified argument to support the contention that a precise count on the
wintering grounds is essential for supporting the primary goal of
maintaining habitat. And to repeat, maintaining the habitat on the
wintering grounds is the only local action we can take in support of the
cranes.
On Fri, Feb 21, 2014 at 5:09 AM, Phil Jeffrey <phil.jeffrey@xxxxxxxxx>wrote:
> > Jim Sinclair wrote:
> >
> > As much as I admire Tom's work and dedication through the years, I think
> he
> > is doing a disservice to those responsible for continuing the work with
> > less experience (that will come with time) and fewer dollars (probably
> > permanently gone).
> >
> If one is attempting to monitor the population of a nearly-extinct species
> with one viable wild flock for the purposes of seeing if it's expanding or
> contracting, highlighting errors is an important part of the process. If
> Tom's statement of "estimated 254 plus or minus 62 whooping cranes in the
> survey area" is correct then the methodology is hopelessly inadequate for
> the purpose intended and needs to be immediately reverted.
>
> If FWS had intended to do anything accurate enough for management purposes
> they would have needed to implement the new methodology in tandem with the
> old one so they would know the accurate count and estimate the errors in
> the new method and tweak it so that it's useful, before dropping the old
> method. What they actually did seems more a function of policy than
> science.
>
> Taking, again, Tom's assertion of his 2% error level (~5 birds) from his
> flights they'd have to average their results for the entire winter with the
> new method to reach his sampling error levels (even if this were a valid
> idea). If you need to save money you run the more accurate method with
> less frequency and *still* end up with far better data. In fact it could
> be both cheaper and better than what they're currently doing.
>
> Phil Jeffrey
> Princeton, NJ
>
>
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--
Jim Sinclair (TX-ESA)
TOS Life Member
Kingsville, TX
"The significant problems we face cannot be solved at the same level of
thinking we were at when we created them." - Albert Einstein
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