Ernie, we disagree on less than you might think. Not sure why you're all agitated. But there are a few points we can keep discussing:
Plain and simple get caught fooling with indigos in Florida and your screwed. Glades Herp Owners Guilty--Lacey Act Violations
Yes, because the
state manages indigos on a hands-off basis, not because they're federally-listed. I think that's worth pointing out. It's a Lacey because snakes outlawed in 1 state were moved across that state's lines.
That's quite a biological contradiction. For starters the indigo has not been neglected. Indigos and panthers share the same environment. Land acquisition, habitat management, also protects the indigos habitat. With habitat loss being far and away the primary issue of concern. Saving the panther habitat is also saving the indigos habitat. It's hands down the most ecologically beneficial thing that can be done for indigos.
It's a matter of
scale. The area of range overlap is small. Yes indigos (& much other wildlife) have benefitted a ton from habitat acquisition and management
for panthers, in a few counties in SW FL. The snakes have not benefited much from all the work to reduce cat roadkill, manage cat inbreeding, study cat movement patterns, etc.
Show me land acquisition, land management, etc for indigos. Hell, show me a single development proposal that's been nixed in FL just because of indigos. It doesn't happen because FWS (in Vero Beach FL;
not in Brunswick GA) isn't willing to declare a place is occupied habitat and thus developing it would constitute a "take". This is
one of the many reasons I say indigos have been neglected, relative to panthers.
As one survey puts it " Our efforts to document the current distribution of the Eastern Indigo Snake indicate that it still occurs throughout much of its historical range in Georgia and Florida".
Again, a matter of scale. Resolution, that us. If the reporting units are
counties, sure, they're still in most counties where they're native. What if the reporting unit was 1000-square mile polygons? Or "tiny" polys of just 100 square miles? (About the size of Webb WMA.) What fraction of the historic range would be reported as "still occupied" using a larger number of smaller reporting units? I believe the honest answer is, the answer would
change, and it would
go down. To illustrate further - flip the problem over and use a single reporting unit - the USA. Has the indigo lost any range whatsoever? No, not at all, because it's still in the USA.
As for old citrus farms, sure they can be great indigo habitat, everyone knows that. They're also great places to build, because the water table is lower than the rest of the landscape, and depth to water is probably the very first consideration for a FL developer. It's never out of their thoughts.
Reliable survey methods for D. couperi are known only for sites where the species use tortoise burrows in winter (Stevenson et al. 2003). ... They also like wood piles, armadillo holes , going down in soft ground, hiding under the front porch and many places where they are very difficult to find.
Depends what you want to know. Things change. We've come
a long way with both detector dogs and population statistics. If you want to estimate occupancy, versus say abundance or density or survival or whatever, and thus you
only need to find evidence of a single snake, once, hey occupancy is fine. You don't need to catch a bunch of animals, over and over again. One shed or turd or eggshell - or DOR or photo - is enough. Another nice thing about occupancy modeling is you can estimate extinction and colonization probabilities for different habitat patches. Of, for example, different sizes or other qualities.
This "occupancy" approach didn't exist before 2002:
http://www.uvm.edu/rsenr/vtcfwru/spread ... season.pdf
For both species much of the population data is via chance encounter.
Whether or not this level or type of data is "good enough" depends on
what you're trying to describe or determine. See above regarding occupancy versus e.g. abundance.
All the data that in the end add up to a guess when it comes to the numbers game.
There are
guesses, and there are
estimates. Behind each estimate there is an estimator - a model. Different types of models have different properties - e.g. sensitivity to violations of embedded assumptions - and require different types of information - survival rates, life span, detection probability, age at first reproduction, number of young produced per repro event, frequency of repro events, how
all these things vary randomly and also vary in association with other factors like prey abundance, etc.
Lots of that type of work has gone into panthers. Much, much less into indigos. Indigo stuff is way, way more seat-of-the-pants than the panther work, if we're talking "how many are there?" I don't really even like that question, for indigos. Measures like "how much of their former range do they still occupy?" are much more appropriate IMO.
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Bill -
The population reduction in a more northern area, the Osceola National Forest wasn't because of houses, IMHO, so much as the agricultural practice of not leaving stumps when lumber pines were harvested.
Pulp wood is/was a lost cause for the habitat. The obvious destruction after clear-cut of the pulp wood seems/seemed hopeless as the trees are grabbed in a huge claw, incised, stacked, and then the whole area is turned over with a disc for the next crop. This is more akin to clearing a field for a crop.
Yeah, stumping & pulping has been a bad, bad thing for wildlife, herps being no exception whatsoever. Luckily Osceola is converting a fair amount of their short-rotation, even-age slash pine stands into uneven-age longleaf stands for red-cockeaded woodpecker management. Osceola constitutes a large chunk of the unrealized potential for recovery (ESA-T) of that particular recovery unit. They have been a
great partner in the RCW recovery effort. The longleaf is not plowed, the groundcover is restored and burned frequently. If we can get gophers back onto the ridges there in meaningful densities, we could get decent numbers of indigos back too.
Global pulp prices are so bad, relative to prices for sawlogs & pine straw, that I'd be surprised not to see a lot of the small private landowners of the lower coastal plain making the switch from one product stream to the other.
Cheers,
Jimi