European pond terrapin
Encyclopedia
The European pond turtle (also called the European pond terrapin), Emys orbicularis is a long-living freshwater species of turtle
.
, West Asia and North Africa
. In the early post-glacial period
, the pond turtle had a much wider distribution, being found as far north as southern Sweden
.
for feeding. Emys orbicularis is usually considered semi-aquatic, as their terrestrial movements can span 1000 meters, and occasionally found traveling up to 4000 meters, away from the water.
, Emys orbicularis adult males are always found to be smaller than females. In males, smaller plastrons offer them a wider mobility compared to females. In females, due to their differential diet and foraging habits, there may be a correlation to an adaptive effect on their skull and head morphology.
turtles. As an Emys orbicularis turtle grows in age and becomes an adult the amount of plant material consumption increases during the post breeding period. Emys orbicularis turtles may prefer less energetic food after the breeding season, a period of time where most of its energy is spent to recover from reproduction.
Nest fidelity is a characteristic that female European pond turtles carry out by selecting a nesting site based on its ecological characteristics and then return there for future expeditions so long as the site has not changed. Emys orbicularis females tend to change to another nesting site if there are visible changes to the present environment or because of dietary changes. If an Emys orbicularis female must change from nest to nest, it will typically select a site in close proximity. In addition, females can also lay eggs in an abandoned nesting site if the conditions change to become better suited for egg survival. If the ecological characteristics of the nesting site changes, this may influence the survival of the hatchlings and their sex ratio. Due to ecological changes such as trees growing to shade the nest, this can change the environment into an inadequate location for egg incubation. Females that do not exhibit nesting fidelity and lay eggs in the same area for long periods of time, even with the ecological changes, may produce large proportions of males as vegetation grows and nesting areas become more shaded. Since the sex of these turtles are temperature-dependent, a change in temperature may produce a larger number of males or females which may upset the sex ratio.
Emys orbicularis species have become rare in most countries even though they are widely distributed in Europe. The building of roads and driving of cars through natural habitats of Emys
is a possible factor that threatens the populations of the European pond turtle. Road networks and traffic often carry complex ecological effects to animal populations such as fragmenting natural habitats and creating barriers for animal movement. Mortality on the road is most likely due to females selecting nests near roads which places a potential danger for the hatchlings as well. Hatchlings that wander too closely to roads are more likely to be killed and put the future population in danger. Although the possibility of roads being a major causation for the mortality of Emys orbicularis turtles is a rare phenomenon, long-term monitoring is necessary. Life span is 40–60 years. They can live over 100 years but it is very rare and unusual.
stepanovi, monogeneans of genus Polystomoides, vascular trematodes of genus Spirhapalum and many nematode
species.
Turtle
Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield...
.
Geographic range
It is found in southern and central EuropeEurope
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, West Asia and North Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
. In the early post-glacial period
Atlantic (period)
The Atlantic in palaeoclimatology was the warmest and moistest Blytt-Sernander period, pollen zone and chronozone of Holocene northern Europe. The climate was generally warmer than today. It was preceded by the Boreal, with a climate similar to today’s, and was followed by the Sub-Boreal, a...
, the pond turtle had a much wider distribution, being found as far north as southern Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
.
Habitat
Emys orbicularis turtles prefer to live in wetlands surrounded by a large proportion of natural, wooded, landscape. Specimens of Emys orbicularis are also found in upland environmentsUpland and lowland (freshwater ecology)
In studies of the ecology of freshwater rivers, habitats are classified as upland and lowland.-Definitions:Upland habitats are cold, clear, rocky, fast flowing rivers in mountainous areas; lowland habitats are warm, slow flowing rivers found in relatively flat lowland areas, with water that is...
for feeding. Emys orbicularis is usually considered semi-aquatic, as their terrestrial movements can span 1000 meters, and occasionally found traveling up to 4000 meters, away from the water.
Human impact
Historically, Emys orbicularis had been maintained as pets; however, this practice has been prohibited due to protection laws. Due to human impact, turtles have been found to be relocated in areas distant from their origin. However, it is possible to localize and indicate a region of origin with genetic testing.Appearance
The European pond turtle is a medium size turtle and varies quite a bit across its distribution, from 12 to 38 cm length. Its shell is brown with a hint of green, spotted yellow.Morphology
An important factor that affects Emys orbicularis development is temperature and thermal conditions. It has been reported that differential growth rates of the same species occur, including variation of body size and clutch sizes, because of varying temperatures in certain areas. Due to evident patterns of sexual dimorphismSexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
, Emys orbicularis adult males are always found to be smaller than females. In males, smaller plastrons offer them a wider mobility compared to females. In females, due to their differential diet and foraging habits, there may be a correlation to an adaptive effect on their skull and head morphology.
Diet
Emys orbicularis turtles eat a mixed diet of plants and animal matter that can increase the efficiency of their digestive process. Although it is assumed that Emys orbicularis turtles are strictly carnivorous, it seems that not all Emys orbicularis are entirely carnivorous as their diet also consists of plant material. It has been reported that an adult's diet starts from a carnivorous to a more herbivorous diet as it ages and grows in size. This is also very similar to other omnivore EmydidaeEmydidae
Emydidae, commonly called the pond turtles or marsh turtles, is a family of turtles. Previously, several species of Asian box turtle were classified in the family. However, revised taxonomy has separated them to a different family. Now, Emydidae, with the exception of two species of pond turtle,...
turtles. As an Emys orbicularis turtle grows in age and becomes an adult the amount of plant material consumption increases during the post breeding period. Emys orbicularis turtles may prefer less energetic food after the breeding season, a period of time where most of its energy is spent to recover from reproduction.
Nesting
Most freshwater turtles lay their eggs on land, typically near a water body, but some species of Emys have been found to lay their eggs distances less than 150 meters from water. The search of a nesting areas by adult females can last several hours to more than one day. Once the location of the nest is established, females spend time for the construction of the nest, laying of the eggs, and closing the nest which can take up to another 4 hours.Nest fidelity is a characteristic that female European pond turtles carry out by selecting a nesting site based on its ecological characteristics and then return there for future expeditions so long as the site has not changed. Emys orbicularis females tend to change to another nesting site if there are visible changes to the present environment or because of dietary changes. If an Emys orbicularis female must change from nest to nest, it will typically select a site in close proximity. In addition, females can also lay eggs in an abandoned nesting site if the conditions change to become better suited for egg survival. If the ecological characteristics of the nesting site changes, this may influence the survival of the hatchlings and their sex ratio. Due to ecological changes such as trees growing to shade the nest, this can change the environment into an inadequate location for egg incubation. Females that do not exhibit nesting fidelity and lay eggs in the same area for long periods of time, even with the ecological changes, may produce large proportions of males as vegetation grows and nesting areas become more shaded. Since the sex of these turtles are temperature-dependent, a change in temperature may produce a larger number of males or females which may upset the sex ratio.
Mortality
Climate has an effect on the survival of Emys orbicularis hatchlings. Hatchlings are only able to survive under favorable weather conditions, but due to regular annual clutch sizes and long lifespan, Emys orbicularis adults, along with many freshwater turtles, balance out loss of hatchlings due to climate.Emys orbicularis species have become rare in most countries even though they are widely distributed in Europe. The building of roads and driving of cars through natural habitats of Emys
Emys
Emys is a small genus of turtles. Its members are:* Emys orbicularis - European pond turtle* Emys trinacris - Sicilian pond turtle * Emys blandingii - Blanding's turtle * Emys marmorata - Western pond turtle- Sub-species :...
is a possible factor that threatens the populations of the European pond turtle. Road networks and traffic often carry complex ecological effects to animal populations such as fragmenting natural habitats and creating barriers for animal movement. Mortality on the road is most likely due to females selecting nests near roads which places a potential danger for the hatchlings as well. Hatchlings that wander too closely to roads are more likely to be killed and put the future population in danger. Although the possibility of roads being a major causation for the mortality of Emys orbicularis turtles is a rare phenomenon, long-term monitoring is necessary. Life span is 40–60 years. They can live over 100 years but it is very rare and unusual.
Parasites
This species hosts several species of parasites, including HaemogregarinaHaemogregarina
Haemogregarina is a genus of haemoprotozoans, parasitic mainly on cold-blooded vertebrates. They are unicellular organisms which are parasitic in the red blood cells.-History:...
stepanovi, monogeneans of genus Polystomoides, vascular trematodes of genus Spirhapalum and many nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
species.