Feeding Frogs?

[Stefan-A]

The question is, are the parasites found inside those WC vertebrates in fact spreadable to our snakes? That's not a poke in the ribs to Stefan that's just a serious question I have that I am having trouble finding answers to...

Duly noted.

The answer is "Yes." Many of them are spreadable. We can get many of them if we eat uncooked or undercooked fish. The fact that both amphibians and reptiles are "cold blooded", already takes down one barrier (temperature) that could perhaps otherwise prevent some parasites from transfering from prey to predator.

worldwide, you are totally right, they're not doing well on a global basis. BUT, in my backyard, with all this rain I can't even take a walk outside without accidentally smooshing a baby toad or frog... so if I need to use a few to get a picky eater off the ground, I do!

Local abundance says nothing about the overall situation. Remember that kid who fed T. brachystomas to his ringnecks? He used that argument.

I don't use them as a steady diet though as there is really no reason to. Garters are easy to switch onto other already dead preys and I don't enjoy decimating wild populations of frogs for my convenience.

Good.

Just to be clear, I'm not being short here to be rude, it's just that it's 2:39 AM.

[aSnakeLovinBabe]

Local abundance says nothing about the overall situation. Remember that kid who fed T. brachystomas to his ringnecks? He used that argument.

If the species of frog in my yard were an endangered species like t. brachystoma I would see it comparable... but considering the frogs in my yard are not endangered, and are not illegal to take, and I need a few every now and then, I feel no shame. As far as the world's amphibian population goes, I can't really do much for them except continue to advise people that on no circumstances should they be releasing amphibians into the wild. People are always wanting to buy bullfrog tadpoles at my store and then say they just want to turn them loose when the change into a frog. Makes me sick every time. Then they get offended when I tell them it's not okay to do that.

[DrKate]

my thinking is that whatever people can catch in their yards probably has less of a parasite load than anything that's been cycled through the pet industry

Yes and no... Diseases do spread better in dense, stressed-out populations such as feeder breeding colonies, and some parasites can thrive under those conditions. BUT... Many parasite species require more than one host species to complete their life cycle - for example, a vertebrate and an invertebrate host - so wild-caught prey that have been living outdoors in a natural environment really do have more of those kind of parasites.

There is also the fact that parasites usually adapt to particular host species. In their normal host, they don't to much harm and are pretty much just along for the ride. But if they get into an *abnormal* host, they can cause severe illness. So a perfectly healthy wild-caught frog could be carrying a parasite that would make your snake very sick (this scenario is most likely for the lungworms already mentioned). Unfortunately, dissecting a specimen and seeing how many parasites you can find doesn't tell you much about whether any of those could in fact spread to your snakes (unless you can identify the parasites and know their biology). If the parasites in your local frogs can't spread to snakes, then eating a parasite-laden frog is just that much more nutrition for the snake.

So my guess is, there are risks to each kind of food source. I wish I could offer more specific information than that. I don't know enough about the parasites of snakes (or frogs/fish/mice/earthworms) to know which parasites and therefore which food sources are most worrisome. And of course, in the case of the wild-caught foods, risks change depending on where you are, what species exactly you're feeding, what time of year it is...

I don't want to make any promises I can't keep, but I may be able to ask some bona fide parasitologists what they think about what prey items are "cleaner" in terms of parasites that would harm snakes. If I get anything useful I'll post back here, since so many of us are using wild-caught prey of one kind or another (even earthworms are part of the life cycle of some parasites).

[Stefan-A]

If the species of frog in my yard were an endangered species like t. brachystoma I would see it comparable... but considering the frogs in my yard are not endangered, and are not illegal to take, and I need a few every now and then, I feel no shame.

Legislation always lags behind and the current status says nothing about population trends.

[Stefan-A]

Unfortunately, dissecting a specimen and seeing how many parasites you can find doesn't tell you much about whether any of those could in fact spread to your snakes (unless you can identify the parasites and know their biology).

So true. However, my point was first and foremost to address the question whether or not they are parasite-laden.

I don't want to make any promises I can't keep, but I may be able to ask some bona fide parasitologists what they think about what prey items are "cleaner" in terms of parasites that would harm snakes. If I get anything useful I'll post back here, since so many of us are using wild-caught prey of one kind or another (even earthworms are part of the life cycle of some parasites).

That would be greatly appreciated.

[celticguitar]

That is a very good question. I think collecting frogs from an area where this an abundance of frog won't destroy the population if you are the only one doing it. There is a local woodland pond where they are so many Green and leapord frogs you almost step on them walking along the edge of the pond. I see atl east 4-5 garter snakes with a casual look. I read that frogs are a good marker as to the cleanlyness of a pond as far as pesticides and this pond has a ton. I saw in a 2 foot area near the shore at least a hundred newly morphed frogs and toads (spade foots!) etc. So there is plenty to eat. As far as parasite load goes? I guess if it's a clean area the load would less? but not nil and I think all live stuff even pet store unless it's frozen dead mice are going to have bacteria and probably parasites because do you think they really care?. If you have a good healthy specimen of snake with a nice clean healthy enviroment I don't think they would overwhelmed but the occasional frog. My garters are wild caught and they look healthy clean and active they came form this pond area I spoke of but I feed them worms and guppies although one ate a frog on the way home because I did have a seperate container for the snake and frog ooops
Dwight

[Stefan-A]

That is a very good question. I think collecting frogs from an area where this an abundance of frog won't destroy the population if you are the only one doing it.

It would depend on the total amount removed from the area.

[celticguitar]

It would depend on the total amount removed from the area.

True but if you are only taking one or 2 I doubt that's much of an impact. I am not advocating it the place I go to is probably over populated as it is and there would a natural die off to keep things in check but then again you are interfering with natural selection and taking away the fit that survive. My green frog came from there and he will probably return in the fall so he can breed next year he's just a summer observation pet for my son and I He's 5 1/2 and I am introducing him to nature up close and personal.
Dwight

[Stefan-A]

True but if you are only taking one or 2 I doubt that's much of an impact.

But why take them at all, when there are better and safer options?

I am not advocating it the place I go to is probably over populated as it is and there would a natural die off to keep things in check but then again you are interfering with natural selection and taking away the fit that survive.

Every population is at its maximum size, overpopulation tends to occur after some dramatic change, as when a species spreads to a new area or a year when reproduction has been exceptionally successful. Or when the size of the population is considered big enough that it becomes a nuisance to us. It's not possible to interfere with natural selection, either. It occurs regardless. It's not like a fragile ecosystem, it's more like math.

I'm trying to keep this short, so I apologise for the lack of illustrating examples.

My green frog came from there and he will probably return in the fall so he can breed next year he's just a summer observation pet for my son and I He's 5 1/2 and I am introducing him to nature up close and personal.
Dwight

Of course it's your choice and he'll probably learn a lot, but I can't see anything good coming from keeping summer observation pets, as far as the animal itself is concerned.

Don't worry, I'm just thinking out loud.

[GradStudentLeper]

As far as feeding frogs is concerned...

Yes. They are good for garter snakes to eat. They are what they feed on in the wild primarily (depending on species and population of course. I work with cyrtopsis in my lab, frog specialists). They provide complete low fat nutrition.

As to the issue of parasites, everything has parasites. You have parasites, I have parasites (90% of us have pinworm, it is often why little spaces inside your nether regions itch, there is a roundworm squirming around where it does not want to be), snakes have parasites, feeder mice have parasites. You get the point. The issue is not whether or not a given prey item has parasites that can be transmitted to the snake. They do. This issue is two fold:

1) Does the snake have defenses against the parasites?

Much like giving native americans small pox blankets, a pathogen a snake has not co-evolved with (If there is a creationist here... I am evolutionary biologist. Bite me) can cause a lot more harm to it than one which it has. There is a cost to an animal to defend against every possible predator. There is not much of one to being flexible with prey choice. As a result parasites are more likely to be able to jump species than their host is likely to be able to put up a strong defense.

Of course what I mean to say here is that by switching to something the snake would not normally eat in the wild (like feeding T. atratus mice) you actually cause more problems than you would be feeding the snake frogs.

2)Does the snake have the resources it needs to deal with the parasites or live with them?

These snakes survive in the wild with the parasite loads of their prey. This must be true, or there would be no snakes. An animal that dies from parasites has other problems like osmotic stress or poor nutrition. IE there just was not enough food to go around that year. This can also happen to breeding females, because they are capital breeders. Unlike a human who is pregant and has odd cravigs for dill pickle icecream, a female garter snake dumps her fat reserves into reproduction. If she has a heavy parasite load and then a bad prey year happens, she dies.

Unless you are doing something wrong, this should NEVER happen in captivity. In fact, you should by all rights have snakes that are so fat and happy you need to worry about obesity more than parasites.

Now this is not to say freaky things cant happen. But they should be rare, rare things, and typically result from other husbandry problems. After all, under far more stressful conditions than exist in your hopefully naturalistic palaudarium (I cant stand seeing semi-aquatic snakes in terrestrial setups) these snakes can thrive and reach very high densities.

Long story short. Go ahead, feed frogs to your snakes. If you are worried about parasites, collect egg masses and raise tadpoles, or hell do what I will be doing for my lab animals and breed your own.

As for whether you should use the frogs in your yard, that is another matter. It depends on where you live and what species they are. Do you happen to know what kind of frogs?