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Lesueur’s Frog

By Alicia Carter

Most of us are familiar with glorious sound of frogs mating after the rain has fallen.  Now is the moment when all frogs will be coming out of hiding and hopping off to find a puddle and a much needed drink.  

You are most likely to see frogs after rain and they can be found around the waters edge or in nearby long grass, under rocks logs or under leaf litter. It is often easier to find frogs at night as you can hear their distinctive mating calls of which I am sure you are all familiar. The chorus that you hear at night is an indication of the health of you local water supply. You can often see foam egg masses in the water edges which are native frog spawn. The cane toad eggs float in spaghetti like strings and it is advisable to remove such clusters if you are certain that these are cane toad eggs.

Frogs are an ectothermic vertebrate, meaning they are cold blooded, relying on the outside temperature to maintain body heat.  These amphibians lay eggs in water that hatch into gilled tadpoles.  These tadpoles develop legs and lungs and emerge onto the land. Most species of frogs require damp conditions or water to breed.  As adults they breathe air through their lungs, but the skin is also an organ of respiration, used to take in oxygen and eliminate carbon dioxide, this is called cutaneous respiration

The Lesueur’s Frog (pictured) makes a soft purring sound which you may hear around creek beds.  This frog can vary in colour from yellow brown to dark brown and has a dark stripe from the tip of its nose, through its eye.  The groin is yellow with black blotches and the belly is white. The skin of this frog species is quite smooth and the toes are padded and quite long and slender.  These frogs can be found around rocky flowing creeks and will breed in still ponds formed near the creek.

The tree dwelling frogs are bright green, the function of this colour is camouflage, in some instances, however, the colour is to make it so conspicuous, that certain predator animals will assume that it would not be palatable. Most frogs are able to darken or lighten their colour's to match their surroundings, by contracting or expanding the various pigment cells in their skin.

Frogs have been around for at least 180 million years and are a valuable nutrient in the food chain as well as an indicator as to the water quality. Scientists all over the world have noted the decline in frog population which they thought was mainly due to human impact on the landscape. They have also found decline in frog populations in relatively pristine environments, which is why frog conservation groups are busily taking note of the frogs of the world. One third of Australia’s frog species occur in our dwindling rainforests, and there are most likely many not yet described.

We can help increase frog populations by not draining breeding sites of water, not introducing new fish species to fish ponds and in fact changing a fish pond into a frog pond. It is also crucial that we prevent the use of poisons around frog breeding areas.

Frogs are preyed upon by all sorts of creatures, wading birds stalk the shallows of water courses, diving birds, fish, freshwater tortoises, larger frogs and of course snakes. The poor frogs are even eaten by aquatic insects in the tadpole stage, one wonders how they manage to survive at all being such tasty morsels, soft and with little or no protection at all.

 

Updated January 11, 2017  

Webmaster: Susanne Ulyatt

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