Reptile & Amphibian Forums

I write all my field observations in a book and after going through the numbers for the last few years there's something very striking (no pun)

Copperheads are getting more common than Gartersnakes in one particular area. There are more surviving adults each year.

Why do think that is?

L

>>Why do think that is?

Any significant change in habitat and/or prey availability? Sometimes housing developments drive species like mice into new areas as their previous homes are razed. Just an idea.
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Chris McMartin
www.mcmartinville.com
I'm Not a Herpetologist, but I Play One on the Internet

I agree with Chris, probably has to do with habitat and prey availability. I was in c. OH last weekend where our group found 15 to 20 Eastern garters. My friends were from s.e. Ohio and commented on the lack of garters in their area, an area where copperheads are pretty common. I lived in that area for three yrs. myself and never saw very many garters, usually only if I was around some aquatic habitat.

Last weekend we started very slowly because we were in woodlands. We found two garters. Everyone was disappointed there weren't more snakes, but when we went to an area that bordered open wetlands, we started finding many garters, which is what we were after.

Copperheads are pretty common in Appalachian foothills, which is the habitat you're talking about, I think. Garters in your area are probably around lakes, swamps, or riverine habitats more, especially ribbons or Butler's or short-headed garters. Good luck.

TC

>>I agree with Chris,

Someone agreeing with me--that doesn't happen too often!
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Chris McMartin
www.mcmartinville.com
I'm Not a Herpetologist, but I Play One on the Internet

there has been some contrustuion and habitat disturbance-industrial work but no building of houses or other structures.

The area sees a far amount of hikers more than a few years ago.

another species in decline is black ratsnakes-I thought that might have something to do with a rise in food for copperheads.

there are other factors but it's difficult to dicuss in an open forum without hinting too much on where the area is.

L

I'm sure it is a local phenomenon, but it could also be attributable to some other causes...

1. Gartersnakes are primarily amphibian predators. Amphibian breeding areas are being disrupted/destroyed at an alarming rate (dams, clearing forest around ponds, drainage or wetlands, pollution) and this would result in a drop in Gartersnake populations. Reduced amphibian populations = reduced Gartersnake populations.

2. Gartersnakes are active far ranging snakes (compared to a copperhead). Unfortunately, snakes that wander around conspicuously and over large distances get killed more often (run over, deliberately killed, etc.) Copperheads may be less inclined to wander around and so are killed less often.

3. Gartersnakes eat more often than Copperheads and are generally less massive snakes. Therefore a gartersnake is more likely to bioaccumulate toxins such as pesticide residues. This is likely to be exascerbated by the fact that they feed on so many fish and amphibians, which also have high exposure levels due to runoff of pesticides into the water.

I will add that down here where I live (SE TX), Eastern Gartersnakes are extremely rare and localized and have been on the decline for 40+ years as best we know. The reason is not clear, but pesticide use, fire ants, and habitat destruction have all been mentioned.
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Chris Harrison

Have there been any significant changes in annual percipitation? When I lived in OK, I found many more garters in rainier years. Maybe they spent more time above ground or maybe there numbers were greater. Also, are there any mass hibernation sites in the area? If so, disturbance of one such site can be devestating to a populus. Just my $0.02

>>Have there been any significant changes in annual percipitation? When I lived in OK, I found many more garters in rainier years. Maybe they spent more time above ground or maybe there numbers were greater. Also, are there any mass hibernation sites in the area? If so, disturbance of one such site can be devestating to a populus. Just my $0.02

Good point. Garters and other natricines love moisture. On my mini-farm I've found all natricines to be much scarcer in dry years, and in Michigan we've been dealing with drought-like conditions for over five yrs. Lake Michigan was down 17 ft. at one point. Our natricine snakes have been much harder to find, including garters. Maybe that's what's happeing in the east too.

TC

sorry it took a bit to reply-I wanted to look into the reasons you all went into:

1. Preciptation about normal to above for the last 3 year-4 years back was a draught.
2. No really lasting changes in the overall environment except for more people using the area.
3. The environment consists of a mountain with forest, lower forest, open field, swamp areas and perminent water source all in a rather small area not more than 30 x 30 miles
4. Doing a little more reading on copperheads in found they eat one interesting thing that has been in abundance for periodcally over the last 8 years-periodic cicadas-which are not considered a problem and are not sprayed for.
5. I haven't seen any declind in insects and the area is banned from insecticide usage by local government-unless a pool were to be found positve for West Nile virus-which is hasn't yet.
6. The area has wide range of herps salamanders, frogs, toads, and snakes-few turtles. It also has an abundance of food animals small mammals, birds, insects, worms, etc.
7. Lastly-collecting the area is banned-but it does go on according to officials and arrest and fine records-this is on the increase. These collectings are not the private person picking up one snake-this commercial large scale poaching for profit. Now all types of collecting are prohibited. Apparently copperheads are not on the list of snakes the poachers bother to collect.

what else would you like to know about the area that might be a hint.

L

please pardon any mistakes in typing-I see there are few.

There are just so many variables in the wild that finding the exact cause would be very difficult. With that in mind: to just throw up some ideas; Perhaps the area is more wooded than covered with dead grass and weeds or perhaps last fall produced an overabundance in dried leaves making the habitat more favorable to camoflauge the copperheads than the garters and predators are reducing the numbers, possibly there is a predator which prefers garters to copperheads and for whatever reason it's population is up for the year, since garters are found in and near water often, possibly there has been a water polutant, there might be a disease targeting the garters and not the copperheads, thee might be a disease affecting he food source such as frogs or fish and not mice and ground squirrels, or with all do respect perhaps the field outings have just turned up more copperheads as of late, it is impossible to know how may snakes are actually in the area when a great deal of there life is spent underground or in inaccessable locations. Like I said here are just too many variables in the wild, I'm sure i didn't even cover half of them.
I wish I could be more helpful,
Nathan

n/p