How long does it take for a tadpole to become a frog?

Do you have a question about anatomy, life cycle, taxonomy, or anything else that isn't covered by the other projects? Ask them here (or provide an answer to other people's questions).

Moderators: Chris Key, Gerry Marantelli, Mod Squad

User avatar
Site Admin
Posts: 15
Joined: Sun Jun 15, 2003 12:00 am

How long does it take for a tadpole to become a frog?

Postby frog » Mon Jul 05, 2004 5:21 pm

There is no simple answer to this question. Life cycles vary greatly between species and, of course, the development of the tadpoles is one major difference.

Tadpole life is often dictated by environmental factors. That is, conditions and evolutionary pressures have adapted the frogs' life-cycles to best suit their surroundings. For example, species which live in arid environments must have a very fast tadpole development in order for eggs to be laid in pools following rain and tadpoles fully develop before those pools dry up again in a matter of days, while frogs which live by permanent water sources can have a much longer development.

Another evolutionary modification is the removal of some or all of the "free-living" tadpole stage. Direct development is where the eggs are laid out of water and the tadpoles pass their entire developmental period on land, and delayed emergence is where the eggs are laid on land and the tadpoles enter the water at a relatively advanced stage of development. About one-quarter of Australian frog species use one of these methods.

Even within a single species, the time taken for tadpoles to develop can vary. There are a number of factors that determine this. One is the temperature of the water (within a comfort range, warmer water leads to faster development). Another is the density of tadpoles - overcrowding leads to the tadpoles metamorphosing at a slower rate (and maturing at a smaller size too). A tadpole can require up to 20 Litres of water for itself before it develops at its full potential.

The final stages of metamorphosis are less variable. Within two to ten days of the appearance of front arms, the tadpole will have become a "metamorphling" and will be more recognisable as a frog.

Posts: 74
Joined: Sat Nov 25, 2006 2:01 pm
Location: Far North Queensland

Postby {~*Laura*~} » Sun Nov 26, 2006 4:29 pm

Some frogs have developed even more bizarre reproductive habits. The time it takes often depends on the supply of food. Many tadpoles can survive with very little food, but obviously more food = more growth. The female Poison Dart Frog (Phyllobates/Dendrobates) ensures her tadpole a safe supply of water and food. Yes tadpole - most lay only one or two fertile eggs at a time. Some lay them directly into a bromeliad, others wait by the egg until it hatches then carry the tadpole on their back (it holds on with its mouthparts) to a bromeliad. Most then return every few days and deposit an unfertilised egg for the tadpole to eat until it metamorphoses. This frogs' time cycle depends on how often she comes back and if she is killed or gets lost, the tadpole will starve.
Also there's the Common Frog or Wood Frog in northern America and Canada - this one takes the cake for long breeding periods. One of these sepcies can become frozen while in its tadpole stage. It is laid in the spring meltwater but the water is so cold it hardly grows. Some tadpoles take three years to develop into their adult form...

Gerry Marantelli
Amphibian Research Centre
Amphibian Research Centre
Posts: 361
Joined: Sun Jun 15, 2003 12:00 am
Location: Victoria

Postby Gerry Marantelli » Tue Dec 05, 2006 11:32 pm

the tailed frog can take 4-6years to metamorphose
many salamanders never do!

Posts: 317
Joined: Sat Dec 23, 2006 3:46 pm
Location: Echuca, Vic

Postby manicackel » Tue Jan 16, 2007 10:39 pm

Yes witness the humble axolotl!! The most boring pet out!! :cry: I am glad you can get frogs now!!

Posts: 4
Joined: Wed Apr 01, 2009 8:43 pm
Location: SA

tadpoles morphing

Postby avidhawker » Wed Sep 30, 2009 2:01 pm

My green tree frog tadpoles took from 6 - 12 weeks to morph.
Next time around if and when they breed i will keep keep the larger tadpoles together as we noticed the larger ones got all the food.
My last morphing tadpole had 4 legs and his tail for 5 weeks yet all the others absorbed their tails within 24 hours of having all 4 legs.

Posts: 391
Joined: Mon Aug 10, 2009 5:01 pm
Location: Tas

Postby ~heket~ » Fri Oct 29, 2010 8:23 pm

The Tailed frog is really odd! and about 5-6 years before they are ready to breed, longest i've ever heard for frogs.

Return to “Think Tank”

Who is online

Users browsing this forum: No registered users and 1 guest