Frogs - Burns Bog Conservation Society

Frogs Vocabulary : herptiles, cold-blooded, amphibians, reptiles, vertebrates, temperature, Pacific Treefrog, Green Frog, Bullfrog, reproduce, froglets, herbivore, omnivore, metamorphosis, prey, predator, habitat, pollutant, indicator species, hibernate, brumate, invasive, native, nourish.

Frogs are amphibians. Snakes are reptiles. There is a word that means ‘amphibians and reptiles’ – Herptiles. Herptiles are coldblooded and they are vertebrates. Cold-blooded means their blood doesn’t keep their bodies warm. They need to keep their bodies at the right temperature some other way. They could bask in the sun to warm up or go into cold water to cool down. Vertebrate means that they have a backbone inside their body.

In Burns Bog we often hear Pacific Treefrogs in the spring. The males call out to attract females. In the summer we often see Green Frogs in the creek or in the groundwater. We sometimes hear Bullfrogs. These frogs are bigger than the others and they are invasive. This means they are not native to British Columbia or even Canada, and they can take over the habitat by eating smaller frogs.

Burns Bog Conservation Society 2013

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rogs are amphibians. Amphibians live part of their life in water and part of their life out of water. The word ‘Amphibian’ means ‘both lives’.

Amphibians are vertebrates, which means they have a backbone. They are also cold-blooded, which means they cannot control their own body temperature from inside. They have to bask in the sun to warm up, or go to the bottom of the pond. Frogs need water to reproduce. Frogs lay their eggs, called frogspawn, in a clump in water. They hatch into tadpoles, then change and grow until they are adult frogs. The first change – they grow back legs.

The second change – they grow front legs.

As they change and grow, they use up the stored energy in their tadpole tails. When they have both sets of legs, but still have some of their tail left, they are called froglets. When frogs are larvae (tadpoles) they only eat plants. They are herbivores. They breathe through water. When they are adult frogs, they eat plants and insects, Adult frogs are omnivores. They breathe air and they can breathe in the water as well. The whole change from tadpole to adult frog is called Metamorphosis. Burns Bog Conservation Society 2013

Frogs and tadpoles are food for other creatures. They are prey to snakes, some birds and mammals and sometimes to larger frogs like bullfrogs. Tadpoles are sometimes eaten by fish. When they are adult frogs, they are sometimes predators. They sit very still on a leaf, on a log or at the side of the pond, and they catch insects. Bullfrogs are predators when they eat smaller frogs. Amphibians have delicate skins. Frogs easily take in pollutants from their habitat. Because frogs may disappear if the habitat becomes unhealthy, we say they are an indicator species. If we can hear them, it indicates that the habitat is still healthy enough for them to live there. If we don’t hear them at all for a season, it indicates that the habitat is too unhealthy for them. People sometimes say that frogs hibernate in winter, but in fact they brumate. They go to the bottom of a pond and burrow into the mud which is warmer than the water. They still need to be partly in water, because they need the water to be able to breathe. Some frogs become ‘frogcicles’ in the winter. They make a sugar called glucose in their liver. This glucose travels to every part of the frog and stops the frog from freezing to death. This is like when your grown-ups put antifreeze in their cars. Find out more…

Here are some links to useful sites. http://www.env.gov.bc.ca/wld/documents/pacifictreefrog.pdf http://www.geog.ubc.ca/biodiversity/efauna/amphibians.html http://www.env.gov.bc.ca/wld/frogwatch/publications/factsheets/frogs/green .htm


Frog round-up! Find the word that means….

1. Has a backbone inside its body. 2. Makes babies. 3. Cannot control its body temperature from inside. 4. Changes as it grows. 5. Eats only plants. Metamorphosis, reproduces, herbivore, cold-blooded, vertebrate.

Q

What happens to a tadpole’s tail as it grows? What does ‘Indicator species’ mean? What is the difference between a predator and prey?

Fill in the gaps using words you find in the text.

A frog is an _________. This means it has two stages to its life. It changes from a _______ to an adult frog. When it lives in the water, it eats plants, we say that it is a _________. When it lives both on land and in water, it eats plants and animals, it becomes an ________. Because a frog has delicate skin, it easily absorbs __________ from its _______. In the winter, a frog ________. Bullfrogs sometimes eat smaller frogs, we say that the Bullfrog is a _______ and that the smaller frog is ____.
