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- The tree frog and other amphibian
The tree frog and other amphibian
All amphibians are protected
There has been amphibians living on earth for millions of years, and it is reckoned that just 50 years ago the stock of amphibians was 5 times higher then it is today. 14 species of amphibians is found in Denmark, 9 of them is living in the Sønderborg-area and 5 of these are under strict protection.
The amphibians under strict protection is; European tree frog, Common spadefoot, Natterjack toad, Moor frog and Northern crested newt.
Amphibians breed in water
Many ponds have vanished in the wish of more farm land or need of space for housing. In the municipality Sønderborg Kommune, an amazing cooperative with private enthusiasts has helped recreate many ponds. However, recreating ponds is not enough, they also need maintenance so they don´t become choked.
Did you know, that frogs lay their eggs in large clusters , while toads lay their eggs in strings?
Observe the amphibians and learn more
Catching tadpoles and observing their development is extremely facsinating. On island Als it is allowed to collect tadpoles excepted those of the tree frog. It is important that you release the tadpoles or developed frogs back in to the same pond.
Amphibians develop in several exciting stages. The simple tadpole grows legs, when it has turned in to a frog the tail disappears.
Natterjack toad
This toad is found at the beach and in areas of sandy tidal meadows with barren vegetation.
The Natterjack toad is becoming rare at many places in Denmark. Here in the Sønderborg-area you´ll only find it on the northern part of island Als and at a single site on Broagerland.
Northern crested newt
This newt is recognized by its warty skin and the orange-yellow belly with black spots. After the larva is developed in to an adult newt, it stays on land and only return to the water during breeding season.
Northern crested newt is easy to recognize with its warty skin and the black-spotted orange belly. During breeding season, the male develops a large serrated dorsal fin.
Moor frog
It is easy to confuse the Moor frog with the Common frog, however there are some distinctive features of the Moor frog, like the knot at the inner toe of the hind legs and the white or yellowish belly without pattern, where the belly of the Common frog is spotted.
The Moor frog thrives in many various types of nature close to ponds. An extraordinary feature of the male during a few days of the breeding season is seen in the photo at foot of the page.
Common spadefoot
Also known as Garlic toad. Outside breeding season, the Common spadefoot likes to live in areas of loose and sandy earth surface. The soil in the Sønderborg-area is very good fertile clayey soil, however with some luck you should be able to find the Common spadefoot on the most northern part of island Als and on the mainland, near Tørsbøl.
That doesn´t look like a garlic? If frightened the Garlic toad secrete a substance smelling like garlic and it is capable of crying out high panic-screams.
European tree frog
Island Als has a very central role in the future of the Tree frog. It is right here, Denmark´s largest population of this little green frog is found. The clear green colour makes it extremely recognizable, however you must remember to look up during the search, it likes to sit between leafs of green.
The European tree frog is found at many spots on Island Als, it is often difficult to spot, however its croaking is very loud an distinctive - it sounds like a hoarse duck.
Amphibians are vulnerable
The amphibians need ponds of clean water without fish! Release of fish in pools and ponds is a threat towards the amphibians; fish eat their eggs and larva. Another threat is duck feeding which leads to water pollution.
Is this the same frog species? The Moor frog male changes his colour and turns blue a few days during breeding season.