from Thomas Bader, English version checked by Rebecca Chapman © by herpetofauna.at

 

After our interesting field trip to Cres during the year 2002 (photos see Gallery) we - a small group interested in field herpetology from Vienna – decided to travel to the Ionian island of Corfu in 2003. So we started on April 25th with our Volkswagen Bus to go South. The journey on the ferry from Trieste to the city of Corfu via Igoumenitsa lasted about 26 hours and all our beer was finished before we reached the island. This helped us a bit to sleep on the hard benches - we did not want to afford booking a cabin!

The island of Corfu (Greek: Kerkyra) formerly known as the Emerald Island (about 600 square km) is the most Northern island of the Ionian Group. Because of the far North – West location the island has about 1200 mm rain a year (more than twice as much as in London). Corfu is known as the greenest island of Greece. The dense population (about 115.000 inhabitants) is concentrated in the area of the capital while the agricultural regions are still farmed in a very traditional way and the scenic landscape of the old olive gardens dominates the countryside.

 

One week ahead of our trip our Italian friends Edoardo Razetti and Massimo Delfino toured Corfu and told us about a reasonable accommodation in the village of Benitses as well as good herpetological tips all over the island - thank you very much guys! After a view problems in our hotel (defect toilet and bath, cleaning of the rooms – we had to change our rooms about four times) we really could not wait to start our field excursions.

Corfu, the island near the Albanian – Greek border has an extraordinary rich heroetofauna. Not less than 8 reproducing species of amphibians and 23 reptiles occur on the island as well as some single records (Elaphe longissima, Telescopus fallax, Testudo marginata and the dubious discovery of the tropical sea-snake Laticauda colubrina) were reported. On a nearby small island the marine turtle Caretta caretta is found as well.

The town of Kerkyra has 40.000 inhabitants – traffic jams and gridlock are common happenings. Nevertheless a manifold of herpetofauna can be found in the city. The most common and ubiquitous species is the dalmatian algyroides (Algyroides nigropunctatus). We found this lizard nearly in every habitat – also in the centre of Corfu Town. The lizard seems to be the favoured prey of Dahl´s whip snake (Platyceps najadum). We found two of these snakes moving on a wall of the old castle. This snake is one of the more common species on the island inhabiting stone walls, ruins and mattock.

While we took pictures of the mentioned whip snakes, Karl caught a big male of the starred agama, also called hardun (Laudakia stellio). This species is quite common in the triangle area of Kanoni - Corfu Town – Achilleion (palace of Emperoress Elisabeth of Austria) and inhabits the top of stone walls, buildings or olive trees. The naturally shy agamas are more trusting in some touristy areas – they can be easily recognised by their typical nervous head nodding.

 

We assessed an extension of the hardun - distribution compared to the known triangle around the town to the West, where its dispersal reaches nearly the coast nearby Sinarades. On the Kanoni peninsula, where the presence of Bufo viridis from literature is known, we could only find water frogs (Rana epeirotica), but no green toads.

A surprise was the discovery of a “new” species for Corfu. While we went for a walk near the harbour of Kerkyra, Christoph discovered some lizards different from algyroides. After a short hunt Karl managed to capture a view of these lizards, which we could identify as wall lizards (Podarcis muralis). We took some DNA - samples and after our return Werner Mayer could determine a Greek - mainland origin.

During lunch time we hardly found any animals, so we decided to spend some afternoons on the shore, e.g. in the North, close to Sidari, where we enjoyed swimming, relaxing and (of course) beer and instead of herps we watched girls! After our stop we started to observe a highly polluted stream and discovered many toad tadpoles as well as a European pond turtle. We could find other specimens of Emys orbicularis in the Ropa valley as well as in the lagoon of the Korrision.

 

During this time of the year the terrapins are difficult to find because of the high availability and stage of water in the water bodies. But nevertheless Franz jumped into the dirty stream and caught the shy turtle. While we drove back we found a familiar butterfly species - the Viennese peacock moth (Saturnia pyri), one of the largest European butterflies.

 

The Central Part:

While we searched for accommodation in the village Benitses, we searched for herps and found five species in a stream pond. After our daily dinner in our favourite tavern (and after a lot of Mythos and Retsinas) we tried to locate the croaking tree frogs – we could hear but hardly find them! Hyla arborea from Corfu and from Central Europe don´t differ a lot, in opposition to Hyla meridionalis from the Western Mediterranean area with the missing lateral stripe. We found tree frogs also in the central mattock ponds as well as in the Gavrolimni area and lake Limni Korrision.

The local subspecies of the newt Triturus vulgaris graecus is common all over the island but nowhere numerous. An extraordinary verification succeeded directly on the beach in Agios Gordis in the West part of the island, where a small beck leads into the sea. In a shallow pool near the estuary of the stream we found about ten green frogs, tadpoles of the common toad and nine common newts. The difference of this subspecies of Triturus vulgaris is detectable during the mating season, when males wear their wedding look. The Southern subspecies graecus and meridionalis have relatively low and flat comb, whereas graecus shows more dark spots, while meridionalis seems more plain and light. Our friend Peter F. Keymar first found the Southern crested newt – Triturus carnifex subspecies macedonicus – which we searched for in vain.

 

 

In Kerkyra the green frog complex consists of the epirus frog - Rana epeirotica and the marsh frog - Rana ridibunda, whereas epirus Frogs are more common all over the island, also in small ponds and streams. The species differ in their voices, at which marsh frogs show their typical laughing and epirus Frogs quack like our Rana esculenta. Both species together colonise the dolines of Gavrolimni, Poulades and Onoufrios, where marsh frogs dominate the quires.

While we hiked down into the dip of Gavrolimni Karl caught two Lacerta trilineata and afterwards he searched for scorpions, skolopenders and clausilians (snails) under some stone and found instead of his primary targets a very agile worm snake (Typhlops vermicularis), which reminds one more of an earthworm than of a snake. On closer examination of the eyes we could realise the subterrestrial pattern of life. It was nearly impossible to take photos of this animals because of its anxious behaviour. It was our only detected specimen – according to literature Typhlops also occurs around Korrision lagoon. Only view minutes after Karl’s catch Thomas could also capture a rare snake of the island – a subadult dice snake (Natrix tessellata). The captured snake was the only melanistic of three observed specimens. The last dice snake reports date back to the Eighties!

Finally after an intensive search Hannes found a huge Montpellier snake (Malpolon monspessulanus) and caught the animal by its tail, while he turned around and tried not to be bitten. This was probably the biggest snake we ever saw in nature – not in terms of length (“only” 160 cm), but in diameter. These snakes have poisonous teeth in the back of their mouth – only really big individuals are possibly dangerous – and in this case it was better to avoid being bitten. After the first aggressive phase the snake calmed down and we could measure and take photos, while the animal lurked like a spectacled cobra. Montpellier Snakes – a frequent snake, which we could find all over the island in dry and wet habitats – awe by their fierce eyes. It is a very speedy snake and really hard to catch and very abrasive while being caught.

 

A very common lizard on the island is the Balkan green lizard (Lacerta trilineata) mostly well disguised in the vegetation and only noticed while making loud noise by taking refuge. We could catch some lizards by hand, most were caught by Karl with his fishing rod. Young “trilis” distinguish from adults by three typical stripes on the back and its brown colour. We all were crazy about these lizards because of their speed, curiosity, courage and appearance and each catch was a highlight of our tour! We doubted the occurrence of the sister species Lacerta viridis for a long time but finally under a metal plate Franz found a semi-adult Common Green Lizard in a karst funnel near Poulades which showed no stripes on the back. We took a tail sample for chemical DNA analysis in the Museum of Natural History in Vienna which will bring the result for species assignment and affinity between both species.

Southwards from Afra to Val di Ropa highly diverse but dryer valleys and hills adjoin to the Tembloni Karst. We could find a high number of the Greek tortoise (Testudo hermanni boettgeri). In spite of trade and impairment of nature and landscape this area seems to be one of the last hideaways on the island, which could also be confirmed by detection of several juvenile tortoises. In addition to this central area the second centre of dispersion is around Limni Korrision, where we also found both juveniles and adults, although a lot of young animals were found dead. At the Korrision a lot of carapaces were injured, which indicates a high number of predators, while in the centre most individuals were unapproachable . We found Testudo mainly in early hours while grassing dewy vegetables, During the hot hours we hardly found any tortoises.

One of our main targets was the discovery of the most beautiful European snake - the Leopard Snake (Elaphe situla) – but – like in Cres – our search was in vain. Our Italian colleagues could find a single animal in Val di Ropa about two weeks before. Contrary to this expectations Michael and Franz accidentally caught the quickest and largest European snake - a Caspian whip snake (Hierophis caspius) under a olive collecting net. This species can grow up to 3 m length, while our specimen measured around 1,30 m and wore the typical youth costume with black points on its back.

One more exemplar was found dead on the road – this species is widely distributed, but although rare and particularly hard to catch. A closely related species is the more common but also smaller and shorter Balkan whip snake (Hierophis gemonensis), which can grow only up to one meter. All Hierophis species are very snappy and aggressive and prefer dry areas where lizards are its main prey. We caught about 5 H. gemonensis in the garrigue and two more in dry pine forests. We recommend gloves on one hand to avoid being bitten and on the other hand to protect yourself against spiky plants.

The two native Glass Lizards of Kerkyra occur often together with whip snakes all over the island. The slow worm (Anguis fragilis) is the second most frequent reptile species after the Dalmatian algyroides. Especially Franz found a lot of slow worms – so we called him Slow Franz - because he always needed a lot of time to take pictures of these also in Austria widely distributed lizards. Thomas once found a clew of slow worms (about 8) under a stone.

The European glass lizard or scheltopusik (Pseudopus apodus) was also common and generally distributed. Mostly lying in damp grass the scheltopusiks take flight very quickly while somebody approaches. To catch this funny looking reptile you have to dive on the ground as soon as you discover it lying down and you can only catch it, when no shrub is close by. After a successful catch Glass Lizards mostly leave some excrements as a souvenir on trousers or shirts!

The South

Going to the South the island becomes narrower and only a few hills rise but the biological diversity seems to be still very high. The island ends in an Eastern direction near the town Lefkimi and the estuary of Chimaros River with huge marshland and brackish water areas and an extraordinary flora. Eminently the Avifauna attracted our attention with species, which disappeared in our homeland long time ago like hoopoes, lesser grey as well as woodchat shrikes, bee-eaters and the tiny scops owl. Also the number of locusts, dragonflies, butterflies, spiders and orchids impressed us a lot.

The marshland of Chimaros is the distribution centre of the agile frog (Rana dalmatina) in Corfu – more North this frog is distributed widely, but not very common. The occurrence of R. dalmatina on an island is an exception, because only few island are populated in the Mediterranean Sea. We found both adults and juveniles of this only brown frog species.

The frog shares its habitat with the Balkan water turtle (Mauremys rivulata), the second terrapin on Corfu Island. But we only found a single specimen, just hatched out view days ago. According to literature Mauremys should be more common than Emys – contrary to this we found three Emys and only one Mauremys. Maybe the water level or the weather affected more observations. Our Italian colleagues found a carapace of a sea turtle an the beach, probably Caretta caretta, which ought to nest on the near island of Nisi Lagoudia according to the report of a native.

An old acquaintance from Mali Losiny – the Turkish gecko – was found in cisterns, waste sites and near villages. Mostly found under stones Hemiactylus turcicus comes out during warm nights to search for prey. The geckos are very filigree and easily lose their tails. In one cistern we found approximately 15 individuals with very different markings on their backs.

Lake Korrision:

Although Lake Korrision is a part of the South we dedicate an own chapter to this lagoon because of its extraordinary diversity and landscape. Huge sand dunes change with marsh land, rocky hills, ponds with fresh and brackish water and farmland with fountains where we could find the rare fresh water shrimps. From herpetolocical point of view we found nearly every species in the hinterland of Korrision. An exceptionally rare snake species, reported from Korrision, attracted us to and lead us back to the lagoon several times. Our obstinacy was awarded during our last evening…

 

We found the Balkan Wall Lizard (Podarcis taurica), a widely distributed but rare species which inhabits mainly meadows and not walls! While on Corfu A. nigropunctatus is more common than P. taurica ionica the relation changes on the more South Ionian island like Zante, where P. t. ionica is the dominating lizard. Here it assumes the ecological niche of the sand lizard of Central Europe.

Franz and Karl managed to catch a Snake-Eyed Skink (Ablepharus kitaibelii) under leave bedding. Though the skinks only have degenerated legs it is very hard to catch them because they disappear somewhere in the soil and can not be found anymore. Furthermore their camouflage is perfectly adapted to the colour of old leaves – so it is hard to say whether the species is rare or not. Our Italian friends found many skinks after rainy weather while we could hardly find a handful in 10 days.

On the first day we found a juvenile grass snake (Natrix natrix persa) near to our accommodation, but we could not catch it. A big one escaped Thomas twice at the Korrision, but he could finally snatch the animal on its favourite sunbathing place during its flight by jumping into the water - a real beauty was the reward for wet trousers.

Another common snake, which we found all over the island (most individuals around the Korrision), is the four - lined snake (Elaphe quatuorlineata). The juvenile and adult colouration differs completely. While young snakes are spotted, the change of colouration takes place during the second or third year of age and turn into the typical striped form. Also their spirit is very variable – while some bite like whip snakes others stay calm while being caught. Four – lined Snakes colonise a wide variety of habitats - from very dry to wet areas, rocky and mossy soil, borders of woods, lakefronts and olive grows.

 

One of our main targets was missing till the last day – it is a Constrictor - Snake, which last was observed on Corfu during the Eighties. So we drove tenaciously to the area of its last observation (which is Limni Korrision) nearly every day to find the Western sand boa (Eryx jaculus). This subterraneous snake can sometimes be found under stones – so we turned nearly every stone in the Korrision area.

On our last evening searching for sand boas, Franz caught a huge four – lined Snake, Thomas caught a 1,60 m Montpellier Snake preying for a trili and Mike caught s skink. Shortly before we wanted to leave, Hannes and Mike turned a stone on top of a stone wall and found a big sand boa, which wanted to hole up into a mouse hole, but Hannes managed to catch the animal and made our day! Sand boas can grow up to a total length of 80 cm - our beautiful striped female was about 60 cm long. The small eyes are typical for subterraneous animals and the acute snout is adapted for digging. Our sand boa excreted a stinking secretion like the Natrix species which did not stop us from taking photos and ... “there is life in the old dog yet”

After this report please take for granted, that we did not injure or hurt any caught animal and we set them free after taking photos – an exception was the taking of some DNA tail - samples for genetic researches in the NHM Vienna

For Corfu - pictures click here: Foto-Gallery