wetlands and biodiversity

Great crested newt  

Their fingertips are allways yellow and well suited to even climb on vertical walls.

In autumn the newt’s move up onto dry land and hide away. They need to fill up and find a secure place for their very first hibernation. Therefore it is important for us humans not too tidy in nature and remove old piles of leaves, rocks and other natural hiding-spots that could also be suitable for other amphibian species. Would we survive winter without shelter from the cold and harsh environment? What we see as a messy backyard might be the home of many individuals seeking shelter and awaiting spring again.

The male newt will prior to mating season from April to July develop a large back-fin starting from the forehead all the way to the tip of the tail and a beautiful  tiger-like pattern appears on their belly!

The newt’s are easiest found on damp or rainy nights but you need to be careful where you step. You need to use a torch. These animals are slow and don’t have the senses that tell them to move away. Instead they freeze upon threat and hope to be unnoticed.

They can often be seen with a lifted head, smelling the air for interesting scents.




A female folding and wrapping the leave around a newly laid egg. Newt’s can lie like this for several minutes without moving which implies that it excretes some sticky secretion to attach the protection leaf for the egg.

Damaged and already pierced leaves like this water-lily, are softer and easier to fold which is why you  are more often find many eggs on these leaves.

A great crested newt has folded the edge of this waterlily leaf to protect the egg. But in this photo it was not so successful and the egg is already disconnected from the leaf and falling off. Although newt’s care for the perfect placement of their eggs many of them end up on the bottom of the waterbody where they will be eaten by larger insects such as dragonfly larvae.

If there is a lack of plants almost anything like leafs or paper will do as protection for the eggs. Inside this paper many eggs can be counted.


Isn t it a wonderfull rose? This was an ordenary kitchenroll tissue with a little stone inside to keep the paper under water.
Soon the long larvae change appearance and gain green-white stripes along their sides. Soon its time to leave this safe environment which has worked like a bubble, holding onto the foetus ever since the eggs was laid there weeks ago.

When observing the development of the eggs it is noticeable that only half of the eggs become larvae. This is the result of a genetic defect from ancient times.

After approximately 6 weeks the surviving eggs have become dragonlike little beeings with gills like antennas and large eyes which very bright when reflecting light. Its organs can even be spotted through their thin transparent skin with strong lighting.

The now very fragile larvae lay in the water almost paralyzed to minimize the risk of being spotted by larger animals looking for food. They lay here waiting for waterfleas to come close enough and when they do, they quickly suck it in to their mouth.


Only a few larvae make it to the adult stage and if they do they can live up to more than 20 year.
In the left picture an approximately 4cm long larvae of great crested newt is being observed breathing with gills. The front right foot is unfortunately damaged on this individual but is prone to grow back again which is subject to extensive research today. It is very unusual that organisms naturally re-grow whole body parts such as feet.

It is only a question of time until humans have understood the biology behind this phenomena.

The larvae is recognized by its black spots on the body and back which is missing on the smooth newt larvae. When developing and progressing in the larvae stage a substantial size-difference is visible between the two species. Initially they live of zoo-plankton and later water fleas and other small insects. At this stage the newt larvae only has a few weeks until the gills disappear and it starts breathing with its lungs instead.
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© Peter Feuerbach