As the weather is warming, the frogs are returning to our ponds. I noticed this year that we have 2 distinct types. So in my usual manner, I set out to find out who was who.

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This plump fellow above is the Green & Gold Bell Frog, Litoria aurea.

Both our frogs are Australian varieties, & both are listed as vulnerable in Australia. Over the last few years we have seen less frogs around the place, so this year, we’re taking the goldfish out of our small house pond, so the tadpoles stand less chance of being eaten. Always handle frogs with wet hands if you need to move them. One reference I found said that these frogs secrete a ‘noxious substance’ but we’ve never had any problems…. just the odd dream of flying, (no I’m kidding! before you go off to annoint yourself with frog slime!).

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This rather warty number is the Southern Bell Frog or the name I prefer is the Growling Grass Frog, Litoria raniformis.

Both varieties of frog can vary widely in colour, from olive green to bright green & with mottled patches. The Southern Bell has generally dark brown or black patches, while the Green & Gold Bell has gold or bronze markings. Both frogs have smooth, single coloured bellies, & their groins & backs of thighs are bright blue.

Both these frogs are avid hunters, when our son was young he used to tie a dead fly on a piece of cotton & dangle it over the pond. The frogs would stand up tall,on all 4 legs & then stalk the fly, just like a cat after a mouse, quite bizarre to watch. They eat mosquitoes & their larvae, also woodlice, crickets, flies & cockroaches, apparently the also eat each other!

One web site I explored about raising frogs in an aquarium, said never to put anything smaller than the frog in the tank unless it was meant to be food.

The eggs hatch in about 3 days, starting off, floating on the surface of the water on a raft of jelly, this gradually breaks up & the eggs sink.Tadpoles are pinkish grey with yellow fins, they live on plant matter & algae until their legs appear. Total metamorphosis takes up to 11 months, but the average time is about 6 weeks.

We do have 4 native species of frog, which live in quite different habitats to the Bell Frogs. If you want to find out more about them, there are some excellent websites, including:

http://www.teara.govt.nz/TheBush/FishFrogsAndReptiles

One of the reasons frogs are important to us, apart from being fun to have around, is that they are indicators of our environment.They have 2 methods of breathing, through the buccal cavity, & through their moist skin, which acts as a semi-permeable membrane,  so anything in their environs acts directly on them. also as insectivores they are a few moves up the food chain, so will suffer from feeding on sprayed bugs.

We have lost 3 of our 7 indigenous frogs, & nearly a third of Australia’s many frogs are in decline, some of the things contributing to this are:

  • run off into water ways of nitrates & phosphates
  • frogs are very sensitive to Round up spray
  • increased U.V.
  • Fungal & viral infections
  • Squashed on roads

January 2014

This year we have resorted to buying in some tadpoles. We got some Golden Bell Frogs & some Whistling Tree Frogs from Nelson. At present they are in a tank, where we can watch them as they grow up. Once they have 4 legs we put them into our concrete pond, which has no goldfish in it. I’m trying to photograph the stages, so will add in more pics as they develop,( having forgotten to photograph the ones we let go last week with all their legs.)

Although we studied the life cycle at school, I’m amazed all over again watching the tiny little legs grow & turn into frog legs, the mouths widen from an (0) into the typical wide frog grin, eyes begin to bulge & the whole shape slim & change. Wouldn’t it feel weird to suddenly have a leg sprout out of your side, or find that you suddenly needed to breathe in a different way? I picked up a set of plastic frogs from Apple Activities, to show the Grandchildren, so they could really get a handle on the changes, of course I like them too!

Bell & Whistling Tree Frog Tadpoles Bell Frog Froglet Froglets

Large Bell Froglet & small Whistling Tree Frog Young Bell Frogs Educational frog Life Cycle

Well, all the froglets have been released & hopefully most will survive. We are certainly seeing more frogs about, only the larger Bell Frogs at present (Feb), it remains to be seen if the Whistling Tree Frogs can survive the Winter to entertain us with their serenades.

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