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A little over a year ago, I wrote "The 300 - No Tadpole Left Behind," describing our rescue of a few hundred tadpoles from a drying mini-pond. The transformation from tadpole to frog was supposed to take about 8-12 weeks, and we were determined to get them all through the process.
It didn't work out that way. While about 1/4 of the tadpoles did transform within that "official" period, most were several weeks late, and quite a few were still tadpoles in July. The last tadpole transformed in August - and was about 36-40 weeks old. This strikes me as a interesting adaptive strategy. In most cases, that late wave will die as their watery home dries out. In an ecology that does feature summer willdfires, however, the ones in lasting bodies of water provide an interesting insurance policy for a species that lives in grasslands et. al.
Along the way, some of the 300 were lost. A prominent biologist in the area told me very few biologists had ever raised this frog, even though (or perhaps because) it's so common. We did the research, but we're also learning as we go with respect to the species. Overall, however, it has gone well - and the journey hasn't quite ended yet.
metamorph
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Over a year later, we've spent several hundred dollars on our little guys, and still have about 30 frogs. Another 173 have been released back into the wild.
Another 80-100 were casualties, which is always depressing but is still well above natural survival rates. We had one tank TPK - fortunately, a small tank. Other tadpoles died for reasons that seemed to have no explanation, or wasted away and refused to transform. We also lost a few frogs, a couple of whom were so small when they transformed that could have sat on a dime and fit.
Pacific Trees Frogs (Pseudacris Regilla) are land-living frogs. They can't be in water all the time, but they can also dry out very easily due to their small size (the very biggest they get is about 2", and most are under 1" when they sit). We learned those lessons the hard way; the only really safe place to keep Pacific Tree Frogs is in a tank with dry areas and substantial water, ideally a wet/dry tank like our 50 gallon Margaritaville.
The transformed frogs surprised us with their colors. Many look coppery, and some even look golden. Others are pure green. Still others are a mottled brown with spots, or grey. When you look at where they live, this is a great palette. Coppery/golden blends into fallen leaves, green blends into green plants by the water, grey works against mud, and brown is good against tree bark, stems, etc. The proportion of these things will vary depending on where the frogs are, and so coming out in all those colors ensures good matches every time for at least some.
The rest of our Pacific Tree Frogs/ Pacific Chorus Frogs have a neat trick up their sleeve. They can change color to match their surroundings - slowly. It takes about a week, but a green frog will become mottled brown if they live in that color environment, brown frogs can go green, etc. All they have to do is survive the discrepancy periods when they hatch, when the terrain dries out, etc.
The other things our new frogs surprised us with was the fact that they weren't very good at catching food. Until they had a few golden chances, they were tentative, often missed their targets, and made me wonder how many die in nature at this stage. We decided to keep them, and put them through a couple weeks of Predator 101 to improve their chances.
Feeding began with wingless fruit flies, tiny things that look like small ants. Dust with Rep-Cal's calcium supplement and Herptivite just before feeding; the supplements are VERY important to ensure that the frogs get what they need to survive, and Rep-Cal's quality is worth the extra buck or two. I didn't know there were dietary supplements to pump frogs up - or a mail order business for wingless flies. But there are. Mail order is much cheaper than the pet shops, which is good, because they eat a lot.
When the 2007/08 rains looked like they would underperform again, I stopped releasing the frogs and resolved to keep them until the situation clarified, because a number of locations I used were becoming dangerously dry. The remaining 70 frogs got a lot bigger, and I had to begin feeding them crickets. Small crickets, mostly, and still dusted with Rep-Cal and Herptivite, but it did get expensive buying 500 a week, even in bulk.
Cute little guys, but hungry. I continue to be surprised at the ability of our frogs to eat a cricket almost as long as they are - then continue to chase more crickets, and simply expand their body like a balloon. Really, a frog is a stomach with legs - the good they do in keeping insects in check is way underrated, until you see how much they'll eat if they get the chance.
As the rains got better, we recently began the release program again. The 30 or so frogs who remain in Margaritaville are all below breeding size; I'm hoping to keep them just a little while longer so they're big enough to improve their survival odds through the no-rain summer and fall.
It had been kind of fun to have their larger companions singing in the house, but it would be cruel to keep them away from the singles bar. Especially after some of them laid a cluster of eggs in Margaritaville.
Will the eggs hatch, and begin the cycle all over again for a 20-30 more tadpoles? I tend to doubt it, but you never know...
This is so cool! Most folks would rescue a furred mammal before they'd look to other classes of critters - you rock!
Walked by the area where we found the tadpoles last year. There was a little bit of water left, and no tadpoles - just mosquito larva. No coincidence, that.
Our working theory is that 2005/06 rainy season was a deluge year, with lots and lots of late rain. We suspect that may have expanded the frogs' range a bit, and the 2006 winter had rain as usual so they would have remained in the expanded range. The vernal pool was the only convenient place for them to breed in spring 2007. The 2006/07 rainy season was very dry, however (less than half normal rainfall). That's why we had to rescue the tadpoles, and the dryness would have made it almost impossible for the frogs to survive in that area over the summer.
After all, I released some of our frogs near streams in 2007, and worry about how many survived there because some of those the streams went dry. In drier, hilly terrain away from the streams? Based on our experience raising them, and seeing their vulnerability to drying out, I'd think there'd be almost no chance. The lack of tadpoles seems to confirm it.
Having grown up in southern California when there were still open spaces there, tadpole collection was on of my spring to-do list, and I wondered each year how the king snakes, fence lizards and burrowing owls also out there were going to fare under the pressure of what I knew was to come.
That always having been on my mind, last spring I also saved a drying pond's worth of tadpoles. Brought them to my East Bay hills backyard pond (removed the goldfish!) and watched them grow. I think we had the larval products of at least three spawnings, given the waves of maturation; in the end there was a robust mixture of Pacific Treefrog and Western Toad. I have not seen the toads since they were an inch long, in July, but did hear a treefrog in December. Surely there is a minimum population threshhold of immature animals that would allow for successful breeding in the next season, so I will try to find another drying pond this year--only with more tadpoles. My aim is to hear the frogs croak and the toads scurry in the dry leaves at night during the summer, all in reclaimed habitat. Spread the word!
I have 9 Pacific Tree Frog tadpoles. One jsut became a frog and hopped onto the dry part of our tank this week. I'm wondering where is the best place to release them in the San Francisco area? I live in the Sunset, near the beach and would love to create a little habitat here in my yard for a few of them, but don't know how ethical this is considering their status in the wild. I live near Lake Merced, which has a marsh area.
I'm also wondering about their feeding after morphing. Should I get my little from some wingless flies? One site said that they don't eat for a month after morph to change from plant to insect eaters. I want to do the best for these little guys and can't get in touch with the person who got me the eggs. Looking for feedback.
renee,
First of all, FEED THE FROGS. You got bad information, and if you wait a month, they'll be dead. We've had frogs eat before their tails have disappeared, and it's those tails that sustain them in the last week or so as their stomachs shift. When the tail is gone or mostly so, the frog is ready.
Wingless fruit flies are a good idea, and you can pick them up at a pet store to get them quickly.
John, great initiative. The pond should provide enough of a water reservoir to sustain the frogs... IF here's enough food around it. Otherwise, the pressure forces the frogs away, and then they're at the mercy of conditions beyond, which may be too dry. Sic transit pseudacris regilla.
If that's so, consider a program that releases just 4-6 frogs in the backyard, so they can stay near the pond. Odds are, there's a breeding pair or two in 4-6. Or, have more frogs and release crickets once a week near the pond.
If there's a marsh nearby, of course, that's ideal as a release area. The things I look for in release areas are:
These are pretty much the conditions you'll want to ensure for any frogs in the backyard, and Pacific Tree Frogs are currently on the "no worries" list so that's not an issue. The issue is doing it right.
Pacific Tree Frogs are small enough that a vast variety of things can eat them. Pond design is driven by that, if you want frog habitat.
For instance, I have friends with ponds, but don't have a lot of hiding places and low, low ground cover because it's all nicely gardened. That's just a free-fire zone for frog predators, so those were off the release list. On the other hand, there's a church around here with a spring/stream, minnows in the water, bridges and mini-culverts where frogs could take refuge, and lots of areas with ground ivys, tall grasses, et. al. That qualifies.
Cats and raccoons are probably the biggest threats, with snakes close behind. But skunks, possums, any small hawks and owls, some other birds, scorpions - even large wolf spiders would be an issue for some of the smaller ones. Eliminating the predators is unwise and mean (except for scorpions - UV light and blowtorch at night works).
To frustrate raccoons and cats, same rules apply as for fish: 3 feet deep, overhangs over the water. For frogs, add lots of crevices etc. to hide in where a cat or raccoon can't fish them out. The rock bordering can help with that. Lots of very low to the ground plants cover (as in, an inch or 3) have a dual role - protection from the sun (key!), and hiding from aerial threats.
The last thing: food.
You can't spray a garden that has frogs with any kind of insecticide. Not only will you kill their food, you'll kill them. But most people don't see the fact that gardens with lots of non-native plants sharply reduce the insect population, because they end up having to deal with the pests and assume the other bugs are all there. Ain't necessarily so.
If you want frogs, native plants are a huge plus with a bunch of other payoffs, beginning with less maintenance. Work with a native plant nursery to bring in some plants that will attract appropriate insects, and your frogs will be much, much happier.
UV light and blowtorch at night works
Hilarious!
bq I love your blog. I have about 20 pacific tree frog tad poles that I rescued from a rapidly depleating puddle. They are currently living in a smallish (2 gallon maybe), filtered aquarium intended for small fish. They are in the very early stages of developement (about 1/2" from head to tail with no signs of metamorphisis). I am feeding them bottmom feeder fish food and will move to blood worms once they get a little bigger. I plan to release them back to the wild when they become frogs. Does this method sound as if it will facilitate the survival of the little guys? Or, are we on the path to destruction? How often should the tank water be partially replaced? Don't they like it kinda funky? I appreciate any feedback!
Brette,
See our orginal article for tadpole care tips.
Cleanlines is actually important to the water. Tadpoles live in swamps, yes, but swamps are biologically active and in toxic terms, are clean. Fish tanks can look clean, but be toxic. Tadpoles are delicate, and have limited tolerance for ammonia et. al. if they build up! Mass die-offs can and do happen very quickly.
Food...
Pacific Tree Frog tads won't really go for bloodworms, and the bottom feeder foods aren't ideal.
Oh, and the UV/blowtorch combo? If you can't get chickens (which will absolutely solve your scorpion problem like nothing else, I'm told), it's probably the next best thing.
Scorpions glow in UV, and are easy to see. But they're often in crevices, and you can't go reaching in for obvious reasons. 2-3 seconds with a blowtorch will settle the issue once the scorpion's location is obvious, however, with minimal fire risk if properly directed. Not to mention zero collateral damage to your local ecosystem.
I personally catch and release the scorpions I've found inside - backing them into a glass jar is very easy to do, they aren't really dangerous to me, and given that calculus I'd rather let a creature live. But if I had kids to worry about, or more venomous species in my area, or felt there were too many (Arizona/NM/TX residents may be nodding at this point), that's a proven Plan B.
Brette, upon review, your tank may be an Eclipse system or something similar. The filter intake is potentially dangerous to the little tadpoles, but from my own experience it is pretty gentle compared to others, and you may get by. If your aquarium has a bio-wheel or other bio-filtration component that you always leave in and don't change, you may be covered.
Observe closely, and look for any signs of injury in your tads.
If you find any, you'll have to switch to an external air pump motor (I lie the small Tetra Whisper) plus a Jungle Dirt Magnet or similar (but not as good) Lee's filter.
We moved into a house with a pond out back. It was built by previous owners. Not extremely aesthetic, but it does have 2 waterfalls flowing into it and I planted some low growing lobelia and snap dragons along the concrete edge. Suddenly, this year we have Pacific Tree Frogs! Where did they come from? We have high walls and did not hear them at all from neighboring yards last year or the creek that is flowing behind our tall block wall. (They are cheerfully croaking as I compose this text.) It just bugs me where they came from. As I said, we do have a stream behind us, but it is way down in a flood control channel, and that is behind a twenty foot tall dirt berm/ block wall. Can they have climbed over that wall? Just wondering.
me and my brother in everett washington rescently found a tree frog on our front long and since then (2 days ago) we have got it a glass cage/ moss/ a heat pad/ rock bowl for water/ a little cocoanut/ sticks and we have also been feading it earthworms. but we have been trying to find another one such as a female beacause its a male. and our frog seems lonley, so we have been looking 2 days for another one but havnt found any. and we want to figure out where we should be looking?