at Fri May 6 17:05:23 2011 [ Report Abuse ] [ Email Message ] [ Show All Posts by RichardFHoyer ]
A forth issue mentioned by Zach is that of 'habitat destruction'. The relationship between species and habitat are a given. So when it comes to loss in a species' or subspecies' numerical abundance, one needs to examine the amount (percent) of lost habitat in relation to the original distribution of a species in any given region. If 50% of a species habitat in a given region has been converted or change in any manner to prevent the species from continued existence, then it is likely the species has lost about 50 percent in numerical abundance.
Having completed a 5 year study of the SRB in the San Bernardino Mts. (1993 - 1997), and having visited the San Jacinto Mts. on a few occasions, I can attest that the loss of SRB habitat in relation to its overall distribution is relatively small percentage wise in both regions.
For instance and in comparison, the distribution of the Rubber Boa use to include San Francisco County as well as neighboring San Mateo and Santa Cruz and western Santa Clara Counties to the south. It may still exist in some undisturbed habitat in southern S.F. county and perhaps on the Presidio (US Army) grounds but otherwise the species has been effectively extirpated over the large part of that county taken over by the city of San Francisco.
The percentage of lost habitat to the species has to be much greater in those West Bay counties than in the San Jacinto and San Bernardino Mts. Where I believe the species has possibly incurred the greatest percent loss of habitat however is in the East Bay regions of Alameda and Contra Costa Counties. The species is also known to occur in the Mt. Hamilton region of eastern Santa Clara County but I have not visited that region so can't say anything about loss of habitat for the species in that area of Calif.
If there is an area where the species might be considered most vulnerable, it would be my belief the East Bay region is the likely candidate for such a scenario. But I wouldn't list the species in any category of concern until proper science-based processes were employed.
As for Zach's view that the Rubber Boa be left to live out their lives in the wild, I share that view but of course, make exceptions. The major thrust of my study of the species involves mark / recapture efforts. It is always a pleasure to find an 'old friend' I originally captured and released in prior years.
Richard F. Hoyer
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