Ecology & Conservation Status of Freshwater Turtles in Minorca Jonathan González

INTRODUCTION

INTRODUCTION

Emys orbicularis (European Pond Turtle)

DISTRIBUTION It has been detected the presence of European pond turtles in 123 UTM 1x1 km squares, grouped in 15 hydrographic basins and 7 wetlands or isolated basins of stream basins.

DISTRIBUTION

HABITAT The Turtles use five types of aquatic habitats. Most of the populations occupy torrents, followed by artificial ponds associated with torrents, temporary ponds, marshes and mouths of torrents. 9.7% 6.5% 9.7% Mouths Marshes Torrents Artificial Pond Temporary Pond 15.4% 58.5%

HABITAT Most of the populations inhabit areas with clayey substratum (83.74%), while the sandy substrates represent 14.63% of the grids and only in 2 localities (1.63%) have been found in artificial substrate. 1.6% 14.6% Clayey Sandy Artificial 83.7%

HABITAT The populations located in an intermittent watercourse have been the most abundant, with a total of 53 UTM 1x1 km squares. The rest of the populations are present in habitats of permanent hydroperiod (28.45%) and temporary (28.45%). 28.45% 28.45% 43,1%

HABITATS

HABITATS

HABITATS

HABITATS

THREATS Several threat factors have been detected in different populations of freshwater turtles. Up to 4 potential threat factors have been observed in some populations. The potential threat factors observed are habitat destruction and modification, water extraction, agricultural and livestock activities, industrial pollution, exotic turtles and mass tourism on beaches. 10.25% 10.25% 2.56% 10.25% 15.38% 51.28%

THE ALIEN TURTLES Alien turtles have been detected at mouths of torrents, canals and artificial irrigation reservoirs in a total of 12 localities of Menorca. In all of them I they share habitat with the European Pond turtle.

CONSERVATION ACTIONS - During the year 2015 the Biodiversity Monitoring Program was initiated, promoted by the Menorca Biosphere Reserve Agency. - Its objective is to provide data on biodiversity and its temporal variations, which will improve the efficiency of management decisions. - The program tries to carry out a long-term follow-up of about 30 emblematic species, threatened or indicative of the territory of the Biosphere Reserve of Menorca. - In 2016, the European tortoise was included, in order to provide annual abundance data to determine species variations, data on its biology, identify threat factors and propose corrective measures.

STUDY ZONE  During the year 2016 it has been sampled in a total of 8 different typology localities located in both the northern sector of Menorca and the southern sector. It is a coastal wetland, 3 mouths of torrents, 2 artificial rafts associated with torrents, 1 torrent of intermittent course and 1 temporary pond.

MATERIALS AND METHODS Minnow traps and hoop traps have been used for the capture of the specimens. Complementary manual capture.

NUMBER OF CAPTURES

EFFORT OF SAMPLING & EFFECTIVENESS

SEX RATIO

SEX RATIO

CLASES DE EDAD

BIOMETRY

POPULATION ESTIMATION

AREA ACCUPIED In closed populations such as Clot d'es Guix or Macarella, it has been possible to determine the area occupied by the pond turtles. It has been taken into account the surface of the water body where the presence of freshwater turtles has been confirmed and a perimeter zone of 50 meters has been estimated.

CONCLUSIONS

ACTIONS FOR 2017 Establish a long-term methodology. 6 new study areas and continue sampling in the above locations. In this way a total of 14 locations will be studied. New capture methods for alien turtles.

Thanks for you attention!