Hey Kids! Did you know that a group of frogs is called an ‘army’? (A group of toads is called a ‘knot’.) In this edition of the Waranga News we are taking a look at Australian frogs.
There are over 2500 species of frogs throughout the world. Approximately 200 species are found only in Australia. Frogs are known as an Indicator Species; that is they tell us something. For example, having many frogs in an area tells us the environment is healthy. However if frogs are suddenly missing from an area or their numbers decline, this tells us that their environment is changing. This could mean a change in the quality of the air we breathe or the water we drink.
Frogs are amphibians, which means they have a double life. At a young stage (tadpoles) they live in water and breathe through gills. As adults they breathe with lungs and live on land. However they need to be around water to breed and keep their skin wet.
Life cycle of a frog
Australian native frogs typically produce 1,000 to 2,000 eggs a year. Whereas the fearful imported Cane Toad (Bufo marinus), can lay as many as 30,000 eggs in one sitting. In spring and summer you will hear male frogs calling. This is the best time to mate and for females to lay their eggs in any water they can find; pools, puddles, swamps. They will even breed in water troughs and buckets filled with rainwater.
Native eggs or spawn appear as white foam floating at the surface of the water; it’s a mixture of air bubbles and clear jelly, rather like beaten egg whites. The female uses her hands as an egg-beater to whip up the froth as she lays her tiny black and white eggs. The foam protects the eggs from sun and predators as they are hidden within and beneath the jelly-coated bubbles. The jelly has an awful taste, which protects the eggs from predators until they are ready to hatch.
Feeding and diet
Frogs are nocturnal and they are often found around lit areas that attract various types of bugs and insects to them. Insects and spiders make up the majority of their diet, as well as crickets, lizards, other frogs and cockroaches and, when in captivity, they will even eat small mice.
Frogs are more often heard than seen. Only males call but both sexes may give shorter warning calls or screams when danger threatens. The males increase the loudness of their calls by ballooning out their throats. Very few Australian frogs make a croaking call; most cackle, grunt, whistle, moan and chime – but the Green Tree Frog is one of the few frogs that do croak; it’s call is a deep ‘waulk, waulk’.
You may be familiar with the call of the Pobblebonk Frog (also known as the Eastern Banjo Frog). Males usually call concealed in floating vegetation or less commonly from land at the water’s edge. The call is a short musical, explosive note producing a resonant ‘bonk’. The call is usually repeated every few seconds. Some individuals from eastern populations can produce a rapid series of ‘bonk bonk bonk bonk’ lasting about one second.
Although frogs are protected across Australia, there are provisions that allow you to capture tadpoles, watch them change into frogs, and then return the juvenile frogs to the place you captured them. It’s a golden opportunity to watch a small miracle of nature in action. Just remember to give the tadpoles plenty of clean, fresh water (rainwater is best) and some food (a bit of boiled spinach or lettuce) and the amazing change from tadpole to frog will take place before your eyes. Remember when they become frogs to return them to where you found the tadpoles.
Would you like to see more frogs in your garden?
Remember that most native frogs prefer cool dark places, so find an area in your garden that is shady. When setting up your frog habitat it’s a great idea to add at least one or two solar lights as these will attract bugs at night when the frogs are looking for food. Plant some frog attracting foliage such as Bird Nest plants, Tree Ferns, Staghorns, and Elkhorns.
Make sure that the frogs have access to water. There are many ways to install water into your frog habitat. You can utilise many containers; try to recycle unused things such as old baths, sinks, laundry tubs and unused bird baths. Remember, if you use a bird bath put a water plant in it as this will deter the birds and give the tadpoles and frogs somewhere to hide.