jshuey at TNC.ORG
Wed Mar 10 11:05:59 EST 2004
Alex brings up the case of Mitchell's satyr and say's:
"And...as far as "collectors" causing butterfly extinctions are concerned,
all know that numerous studies have been made by scientists including Paul
Opler, Paul Ehrlich etc. in which experiments were made, where deliberate
attempts to wipe out a butterfly colony by overcollecting in the colony
proved impossible...The idea of "collectors" causing extinctions of
butterfly species/subspecies has never been documented anywhere and must be
considered as a total myth...And the truth of the extinction of Mitchell's
Satyr in NJ is now becoming widely known..."Collectors" did not cause the
butterfly to disappear in NJ as "someone" wrote (and it probably still
exists there unknown to us)...it was loss of habitat resulting from
excessive development, and in at least one case, a colony was destroyed by
overgrowth of sedges caused by the cessation of mowing of the vegetation
where the colony existed (under a power line - and there is another rumored
cause of this extinction)...As it has been pointed out, "collectors" have
collected for decades in Michigan's Mitchell's colonies, without the loss of
a single colony, and I also hear that more colonies have been discovered in
Michigan, as well as in several other states (so just WHY is the species
"endangered"???)...But a freeway is NOW being planned in Michigan that would
extend RIGHT THROUGH a major colony..."
First - it's not that cut and dry - and we discussed this at length years
I've attached an old email initiated by Bob Kriegle in which I laid out what
I knew at the time. Not much has changed relative to this particular story
since 2000 (we have annual recovery team meetings where all new info is
discussed - in fact this year's meeting is tomorrow in Lansing MI). The
major change is that the research I talk about below is finally "in press"
in American Midland Naturalist.
As to the Highway Alex refers to cutting through the population - that plan
was abandoned about three years ago. The new HW route (US-31) simply
diverts to the west of the fen and merges with I-94 for a mile or so (at a
cost savings relative to going with the original route).
So read below if you are interested in the murky gray story behind the
Mitchell's satyr debate.
Director Conservation Science
Indiana Office of The Nature Conservancy
> -----Original Message-----
> From: jshuey at tnc.org [mailto:jshuey at tnc.org]
> Sent: Wednesday, May 17, 2000 9:22 AM
> To: leps
> Subject: Re: Extinction of Mitchell's Satyr by collectors
> Bob Kriegel asks a hard question below. I'll provide as much information
> can, and then let you decide. If you want the short answer, my bottom
> that I don't know.
> kriegelr at PILOT.MSU.EDU wrote:
> > I know that there are list participants out there who have more
> > on the truth-or-urban-legend of the statement below.
> > > It is widely believed that Mitchell's Satyr was eliminated from its
> > > known New Jersey location by collecting.
> The evidence that led people (and by people I mean Dale Schwietzer, at the
> a TNC employee) to believe that collecting played a role is as follows.
> 1. Dale visited one of the three sites himself on perhaps the last year
> recorded from the fen. He never saw a mitchell's satyr at the site, but
> find a glassine envelope laying on the trail, indicating that a butterfly
> collector had proceeded him to the site.
> 2. The collector (some New York City MD., now deceased) that really knew
> two, possibly three sites really did collect the hell out of the
> One needs only visit the American Museum of Natural History to see the
> drawers of specimens collected from these small populations in just a few
> years. Several hundred specimens in total. The data on the specimens are
> purposefully cryptic, such that you can't really tell where they were
> from (hence the confusion of how many sites there really were). The other
> thing you notice when you look at the data, is that this guy collected the
> 3-4 times a week during the 2-week flight period. And when you look at
> quality of specimens, you get the impression that he bagged every specimen
> encountered (there are lots of complete rags in the series). If ever
> was a collector who typified the stereotype bad stamp collector mentality,
> guy was probably it.
> So that was the evidence at the time - circumstantial to say the least.
> Confusing the issue is the condition of the two known sites (based on
> conversations I've had with New Jersey Heritage staff). Both fens are
> degraded, suffering from invasion of red maple (either fire or beaver
> played a role in maintaining the open nature of the habitat). This
> was well underway when Mitchell's satyr was declining. Today, these fens
> seem likely to be able to support the butterfly, based on habitat size
> (unless someone has been managing them since I had these discussions a few
> years back). Hence, it seems likely that habitat dynamics alone could
> been responsible for the ultimate decline of the butterfly.
> > Other than a presumed increase in collecting pressure, what evidence is
> > there that the last population was eliminated by collectors?
> Now I want to confuse the issue further, based on some recent work on
> Mitchell's satyr in SW Michigan.
>Based on two years of mark-release-recapture data at two sites, here is
> what we know about population structure relative to these issues.
>A) Populations at these sites were fairly small, somewhere between
> total adults.
> B) With daily effort, we were able to capture around 50% of the
> each year.
> C) Fecundity is apparently pretty low, with most females laying 5-10
> day over about a five to seven day period. There is no initial large
> eggs produced from what we can tell.
> D) vagility is very low - most females move less than 50 meters during
> life span.
> So, if you factor in this information, it does seem likely that you
> the course of a several year effort, cause a serious decline in small
> populations of this species. For example, if we had been killing females
> instead of writing numbers on their tushes, I bet we would have knocked
> study populations down by about 50% over the two years.
> But now, I'll confuse the issue even further. Two sites in Michigan have
> the brunt of collecting over the decades, Wakelee Bog and Liberty Fen
> partially owned and managed by the Conservancy). Both support very
> populations. In the case of Liberty, the population did decline
> the mid 80's, but has now recovered. At Wakelee, the population has
> seemed very robust (likely much larger than the populations were we did
> work). This despite a long and glorious history of collectors driving
> over the country to collect these two sites.
> Now and interesting aside: the southern subspecies, Neonympha mitchellii
> francisci, was emergency listed because of the threat from collectors.
> species was described by Parshall and Krall, two collectors who are of the
> classic long series mind set (as in the longer the better). Remember,
> was one of the three collectors later convicted for violating several
> laws regarding endangered species and collecting in protected
> areas. Hence, when North Carolina heritage staff visited the only known
> population site (type locality) and could not find it, they naturally
assumed that it had been
> collected out of existence. (keep in mind that heritage staff have long
> under the influence of Dale Schwietzer's opinions, and hence were already
> that New Jersey populations had been "collected to extinction").
> So the story started (as part of the emergency listing) and persisted (I
still see it
> kicked around, most disturbingly in the recovery plan for this
> North Carolina populations were collected to extinction.
> As it turns out, this was all a big screw-up. The map to the
> type locality (provided by the authors) was bogus. Of course the
> population at the site was "extinct". Once folks finally figured out
> type locality really was, they found the butterfly. But the story still
> persists as urban legend. As it turns out, the exact spot where the
> originally discovered has indeed gone temporarily extinct (the habitat has
> over). But the real population persists in the impact range of Fort
> apparently healthy and thriving in the habitat maintained by a steady
> procession of bomb-induced wild fires.
> The repercussions of all of this persist to this day. A small set of
> populations have recently been discovered in another east-coast
> state. The perceived threat of collectors is so great that almost nothing
> known in the general conservation community about the sites (for example,
> yesterday I was talking to the guy working on Mitchell's satyr at Ft.
> he heard that the new populations were in the mountains, I had heard that
> were in the piedmont - and we are both heavily involved in conserving this
> > Folks, this one is worth airing out. This extinction event has been
> > referred to in Nature Conservancy literature and in National Geographic
> > magazine. It is the most widely cited case in North America for the
> > extinction of a butterfly population by collectors. I have heard strong
> > opinions on both sides of the argument about this event. !
> > What I have not heard is evidence
> > Bob Kriegel
> The bottom line is this, as a TNC employee, it almost killed me when I
> printing this "factoid" in our national publication (this goes out to
> million members). National Geographic hits even more folks - and both are
> supposed to be pretty authoritative. I think that the evidence is way to
> to say with certainty that the story is fact.
> On the other hand, if ever there was a convergence of factors
> ranging from a susceptible species to a collector who could actually put
the hurt on a
> population, New Jersey is it.
> So, years into pondering all the evidence I've come to the conclusion that
> there really isn't a clean answer to this issue.
> John Shuey
> Director of Conservation Science
> Indiana Office of The Nature Conservancy
> phone: 317-923-7547
> fax: 317-923-7582
> email: Jshuey at tnc.org
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