Nature Photography

One of the anuran species seen on a regular basis in The Netherlands is the Common brown frog (Rana temporaria) (photo right), one of the first amphibians to emerge from hibernation at the onset of spring. Clutches are often found in large groups together. They usually float near the surface of the water they were put in. In this way the eggs catch as much warmth from the sunrays as possible.

The Common toad (Bufo bufo) (photo below, amplexus) is a well-known amphibian to a lot of people as well. This species can be seen early in the year when large groups can be seen migrating to the ponds where reproduction will take place. The difference between egg-clutches from frogs and toads found in The Netherlands can easily be distinguished; frogs lay their eggs in lumped clutches, toads in the shape of long strings, often attached to aquatic plants.

Male Common toads (Bufo bufo) search for female toads and mount her subsequently (this is called amplexus, photograph left). This often happens already while migrating to the ponds where reproduction will occur, so couples are at times observed as well. Sometimes however individuals make 'mistakes', in such cases 'mixed' couples are observed. On the photograph below a male Common toad and a female Common frog (Rana esculenta complex) are seen.

Well into the summer season the Common green frog (Rana esculenta sp.) can be heard. During the mating season the males are often found croaking in large groups in ponds (picture left). At times they can be heard from quite a distance. Different sounds are made, for example to attract females or repel other males. Nowadays the Common green frog (in fact there are three different species) is frequently seen in garden ponds and even reproduces in such cases.

Moorfrogs (Rana arvalis) strongly resemble Common brown frogs, but the species are not related. These animals are frequently found in moors. A ligt dorsal stripe is one of the characteristics as well as the slightly more pointed head. Moorfrogs make a typical sound (usually in March, sometimes a lot earlier). Sometimes the reproductive season only lasts one week. Males show a very nice blue coloration for a very short period during the reproductive season (photograph on the right).

This rare species is mainly found in the Eastern and southern parts of The Netherlands. In the provinces of Noord-Brabant and especially Limburg a fairly large number of species can be found. At the right a photograph of the Tree frog (Hyla arborea), a real sun-loving amphibian. This one (below) was seen on the leaf of a blackberry bush at a temperature of about 30 °C.

Another rare species in The Netherlands is the yellow bellied toad (Bombina variegata) (pictures left). Its distribution around here is limited to parts of the province Limburg. This species can be characterized as a pioneer species, i.e. it is one of the first animals able to colonize 'new' terrain. The animals are capable of colonizing all kinds of temporary pools and ponds. Until a few decades ago cart tracks filled up with rainwater, as well as cattle-ponds were often important sites for reproduction for this species.

The Common Spadefoot (Pelobates fuscus) (photo on the right) is a rarely observed species, which spents most of its days hidden deep in loose soil. The males call submerged, but can easily be heard. During the past 30 years this species declined rapidly, one of the main reasons being the loss of habitat. At a small number of locations in The Netherlands the Spadefoot can still be found. During the mating season thick gelatinous bands of eggs are layed in shallow water. The tadpoles may reach a lenght of 10 centimeters.

Natterjack Toad (Bufo calamita) is a digging kind of toad. It is smaller than its relative the Common toad (Bufo bufo). Characteristic is a dorsal yellow line. Its main habitat should have a sandy soil to accomodate this digging species. The eggs (3000 to 4000 per string of eggs) are deposited in small temporary pools (often rich in algae that provide food for the larvae): therefore the larvae develop quickly. The diet consists mainly of insects. Males make a loud sound that can be heard from a far distance.

To the right a photograph of the small Smooth newt (Triturus vulgaris). This is about the most widespread newt species in The Netherlands. In this case a male specimen during the reproductive season. Most male newts develop a high keel on the back together with intensified colors during the mating season. Colors like red and blue can be observed at the part of the keel around the tail. After an elaborate display of courting the eggs are fertilized and produced. The female newts glue the eggs to aquatic plants and fold the leafs around them.

At the right (a male) and left (a female) two specimens of the Great crested newt (Triturus cristatus) are shown. This is the largest species of newt found in The Netherlands. In this case the males also develop a high keel during the mating season. The skin is warty and a white line can be detected along the tail. The animals have a bright orange belly with black spots in a particular pattern on it. This pattern is highly individual and can be used as an individual marker for identification purposes.

In the South and Southeastern parts of The Netherlands the Alpine newt (Triturus alpestris) occurs. In other occasions the species has been set free and in some cases seems to be succesfull. This newt may be found in a variety of different aquatic environments during the reproductive season, often in ponds in forested areas. Sometimes these ponds do not contain any plants that can be used for depositing the eggs. Under such circumstances eggs may be glued to all kinds of different material such as leafs and small pieces of wood. Both sexes have a beautiful orange belly, rarely spotted at the throat (right photograph). Females are dark-green, males dark-blue, both having small discolourations on their backs. During the mating season males have a low black-and-white keel.

The Palmate Newt is a species reaching its most Northern distribution in the South of The Netherlands. It somewhat resembles the Smooth Newt and females from the two species are almost indistinguishable. Males do not have the high crest that male Smooth Newts do have. They do however have a short tail filament (up to 5 mm) and webbed feet. The species is tolerant to acidic consitions (low pH-value). Total length up to 9 cm.

On a few locations in Limburg quite a rare species can be found, the Fire salamander (Salamandra salamandra terrestris) (photograph above). This is a real land salamander, even mating occurs on land. Larvae of this species hatch inside the female and are released in small ponds and streams. These hunt for small crustaceans. As is common in newts and salamanders the gills are situated outside the head. Following metamorphosis the young salamanders go ashore and start their terrestrial life. This species can reach a respectable size compared with most newts. Due to its hidden lifestyle however it is rarely seen.