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In a message dated 1/3/2014 5:01:01 P.M. Eastern Standard Time,  
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Have you seen this paper?
 
January 4, 2013
 
Marty Martin
 
re: Population declines of eastern indigo snakes (Drymarchon couperi) over  
three decades in the Gulf Hammock wildlife management area, Florida, USA by 
J.  Steve Godley and Paul E. Moler (Copy here attached)
 
Marty:
 
Thanks for bringing this paper to my attention. This study, if one may call 
 it such, only confirms the obvious. The sample sizes are too small for the 
 results to be of any significance other than to indicate an undeniable 
trend  toward extinction. Several of the assertions need to be challenged.
 
let me begin with the presumption, common among herpers of a certain age  
and explicit in this paper, that many once common herp species prefer 
disturbed  habitats. If that were true there would be more herps than ever, 
especially wide  ranging generalist species such indigos and kingsnakes. 
 
As you know, kingsnakes though largely extirpated today were until recently 
 found from the Atlantic to the Pacific and everywhere in between except 
for the  driest deserts and the coldest mountaintops. Unlike indigos which 
have large  home ranges and are thus greatly subject to road mortality 
kingsnakes were until  recently capable of living in densely populated areas. 
Nevertheless, they are  now gone. The bottom line is that climate and 
biogeographical history are the  only constraints to the range of either Drymarchon or 
Lampropeltis.
 
Past "studies" have indicated that indigos require gopher holes for shelter 
 but nothing could be further from the truth, they are neither habitat nor 
prey  specific and prior to their decline could be found anywhere throughout 
their  range eating whatever they could stuff into their mouths. Over the 
course of my  herping career I have been privileged to have seen quite a few 
Drymarchon here  in Florida, in Texas, in Mexico, and especially in Belize 
where they are one of  the most common snake species. Within their range they 
may be found in virtually  every habitat from seashore to mountaintop, from 
marshlands to savanna to the  deepest jungle. Having said that the 
preponderance of my observations have been  made in undisturbed or relatively 
undisturbed habitats. That is especially true  of large individuals. Nowhere is 
that more true than in Gulf Hammock which was  for the most part forest 
primeval until the 1970s and was full of big indigos. 
 
Moler's observation that indigos in Gulf Hammock preferentially occupied  
ten year old clearcuts is misleading. Disturbed and especially edge habitats  
often experience a temporary increase in biological productivity that can 
be  exploited by top trophic level species like indigos. It does not follow 
that  these peripheral feeding areas are somehow more important to the 
species than  the core habitats to which they are primarily adapted. For example, 
in late  summer timber rattlesnakes often utilize the edges of farmer's 
fields at the  foot of the mountains that are their core habitat. Does it follow 
that farm  fields are more important than hibernacula? Grain farming 
produces an  unnaturally high concentration of rodents yet rattlesnakes continue 
to decline  everywhere except where large areas of core habitat are 
protected. Unless I am  mistaken both indigos and rattlesnakes were doing quite well 
prior to 1492  despite a lack of disturbed habitats and heavy predation by 
indigenous  Americans.
 
Sampling bias also leads to the false impression that anthropogenic  
disturbance is somehow good for herps. Old herpers such as ourselves fondly  
remember the days when flipping a piece of tin would often turn up a snake. Try  
it today and all you will find are a few fire ants. That is even true in 
those  rare instances where an old house with tin abuts a protected core 
habitat. It is  tempting to blame the fire ants, or a combination of all other 
such factors such  as habitat destruction, road mortality, etc, but none or 
even all of those  factors can fully explain the decline. More on that in a 
moment.
 
The most common form of herp census, and the primary method used in this  
study, is by means of road cruising which can lead to false conclusions. The  
roads in Gulf Hammock predominantly pass through clearcuts. That is why the 
 roads were built in the first place, to destroy the forest. Only rarely do 
the  roads pass through significant stretches of undisturbed forest except 
in the  case of deep swamps. Indigos will live in swamps but it is not their 
preferred  habitat so it should not be surprising that the majority of 
specimens are found  on stretches of road surrounded by ruined habitat. 
 
It is often said that it is difficult to find snakes in the jungle and that 
 is true. Ecotourists can wander for weeks in the rainforest and never see 
a  snake. But build a new road through undisturbed rainforest and presto 
snakes  cover the road until the inevitable decline due to road mortality. 
Should we  suppose that the sudden increase in snake observations means that 
roads are the  preferred habitat of snakes? It is all a matter of sampling bias.
 
The most egregious error in this report is the assertion that,  
"environmental pollution, disease, and climate change seem to be insignificant  or 
discountable factors at this site". I would agree that pollution and climate  
change are negligible factors. There is little or no pollution in Gulf 
Hammock,  and climate change should if anything be of benefit to the indigo which 
is a  predominantly tropical genus. 
 
There is no reason whatsoever for the authors to assert that disease is not 
 a factor. They offer no explanation for this position for the simple 
reason that  they have no information. Lack of evidence is not evidence of lack. 
They have no  information because when a snake gets sick it crawls into a 
hole and dies never  to be seen again. It is very difficult to study epizootic 
incidents in cryptic  species because you can't study what you cannot see, 
but there is an ever  increasing body of indirect and anecdotal evidence 
that points to invasive  pandemics as the underlying cause of reptile decline 
not only in Gulf Hammock  but throughout the world. 
 
There is no denying that the "usual suspects" such as habitat destruction,  
road mortality, direct persecution, pollution, climate change, and fire 
ants all  contribute to the decline, but not even the sum of these factors can 
explain the  sudden widespread disappearance of otherwise successful 
generalist species  throughout their range. 
 
Frogs and turtles are much more easily studied than snakes and so there has 
 been a recent avalanche of empirical evidence that both of these groups 
have  been devastated by several recently emerged pandemic diseases spread 
initially  by anthropogenic means. 
 
As you know, I am interested in the possibility that Ranavirus may be one  
of the primary culprits in the overall decline of our herpetofauna. It is a  
devastating disease to which almost all exothermic taxa are susceptible to 
some  degree. I know from personal experience that in turtles it spreads 
rapidly, has  a very high mortality rate, and can kill susceptible individuals 
within a week.  You are highly unlikely to find a snake in the field which 
is suffering from  such a virulent disease. It will either be uninfected or 
dead, a moldering line  of vertebrae somewhere in a hole in the ground. 
 
It is worthy of note that both indigos and kingsnakes are primarily  
ophiophagous species that eat other snakes that eat frogs, some species of which  
such as bullfrogs are relatively resistant to Ranavirus and have been shown 
to  carry the disease. Likewise, it is worthy of note that those species 
such as  rattlesnakes that are primarily rodentivores have been less affected 
by mass die  offs despite the impact of habitat destruction and direct 
persecution.
 
I am a field naturalist not a scientist per se, so I cannot say with any  
certainty that Ranavirus is the primary factor in the decline of indigo 
snakes  in Gulf Hammock but I strongly suspect that it is. One should not 
conclude from  this that other pathogens, land management practices, or 
environmental factors  are not involved.
 
There is one more criticism of this report that I must regretfully mention, 
 a conflict of interest concerning the authors.
 
Mr. Godley is an environmental consultant who works closely with the  
phosphate industry and other development and resource extraction industries. He  
was instrumental in preparing the biological inventory and other such 
reports  necessary for the permitting of the King Road Mine in Gulf Hammock, a 
project  which will further fragment and destroy what little is left of Gulf 
Hammock’s  original forest ecosystem. Mr. Godley knows what side his bread is 
buttered  on.
 
It is a sorry fact that throughout the nation the integrity of the  
environmental consulting industry has declined faster than the ecosystems they  
purport to study. They are bought and paid for either by industries that 
require  permits and are loathe to see results that might negatively affect their  
projects, or by governmental bureaucracies that seek to maintain the status 
quo  for political reasons. Such is the case with the ill named Florida 
Fish and  Wildlife Conservation Commission which has muzzled its finest 
scientists  throughout their careers. In either government or industry if you rock 
the boat  you are out the door.
 
Some say that advocacy has no place in science but I disagree. Should we  
respect the opinions of climate change denialists simply because the data are 
 inconclusive and they are doing their jobs on behalf of their masters? 
What  about those who study dying ecosystems and come to no conclusions other 
than  that we need more studies (for which they get paid)? When I see a bug 
stop a  future pipeline I might change my tune, but the days of the snail 
darter are  gone. In a time of diminishing resources business always wins.
 
As for Gulf Hammock and indigo snakes it is probably too late. The forest  
is gone and the wildlife extirpated or extinct. There is no easily 
foreseeable  cure for any of the presumed disease issues. 
 
Nevertheless, if the political will existed there are steps that could be  
taken. Here is my wish list.
 
Other than small private inholdings, many of which contain the last  
remaining patches of original forest, the entirety of Gulf Hammock should be  
confiscated by the government and those responsible for the environmental crimes 
 should be imprisoned. Their sentences could be reduced through the 
provision of  field labor necessary for the ecosystem restoration program. For 
example, the  CEO of Georgia Pacific could get a one hour reduction in his 
sentence for every  Monsanto brand pine tree he cuts down with a rusty hatchet. (I
’m channeling Pol  Pot here.)
 
The good news is that the destruction of Gulf Hammock is a relatively  
recent event so the germs of life remain in the seed bank. Likewise, a small  
amount of intact hammock remains in the nearby Waccasassa Bay State Preserve. 
In  a few hundred years all should be well provided that the whole place has 
not  been submerged by rising sea levels.
 
Meanwhile back at the lab leading scientists such as Paul Moler could be  
working on reintroduction programs rather than just documenting declines. I 
just  said that there is no foreseeable cure for an epizootic event once the 
cat is  out of the bag but that is not necessarily true in the long run. All 
diseases  either die out or coevolve with their hosts through a lessening 
of virulence.  Even such plagues as water hyacinth and fire ants are slowly 
coming into  “balance”. The problem is that coevolution cannot happen if the 
host is missing.  Therein lies the value of reintroduction programs no 
matter how hopeless they  may seem at first. All you can do is try. Without such 
efforts there is no hope  whatsoever because extinction is forever. As for 
keystone creature such as bears  and panthers all they need is a little 
boost and a lack of bullets.
 
So I reject the paper’s finding that the cause(s) of indigo snake decline  
in Gulf Hammock are unknown and that nothing can be done. Meanwhile I will  
cherish the memory of a giant indigo glistening in the winter sun along 
Spring  run in what used to be Gulf Hammock.
 
Bruce J. Morgan
Environmental Designs
POB 1519
Archer, FL 32618  USA
352 495 9748
_www.environmentaldesigns.org_ (http://www.environmentaldesigns.org)