Human Threats: For both of these species the common habitat is the Marram grass and fresh water regions within the Nature Reserve. As there are many contributing factors to the loss and damage of both of these habitats, it is difficult to pinpoint which factor causes the most destruction. Habitat loss and fragmentation, an overall decline in groundwater quality, water pollution incidents, water shortages and predation from feral populations such as ducks and competition from introduced exotics such as the common frog are all reasons for the decline of the Agile Frog. For this reason the States of Jersey aim to reduce all the possible threats to the region with the aim of steadying the numbers of both species. Firstly, one of the main threats
…show more content…
The damage caused by fires this year was at its lowest point in four years, with only 1,140m2 of gorse being destroyed in two small fires. However, in previous years the damage from fires has resulted in substantial areas of the nature reserve being destroyed. This destroys the habitats of the wildlife found in the dunes and can take long periods of time to regrow and be inhabitable again. One factor that has played a big role in the depletion of the number of Agile Frogs has been pollution. In 2012 two pollution events occurred. The first, a pond in the SSI became contaminated with fuel, which was one of the major breeding sites of the Agile frog and badly affected the water quality. The second, 10 barrels full of oils and solvents were dumped on the site, leaking into the surrounding area. Furthermore, the Transport and Technical Services ranger team have been clearing away huge quantities of general waste and illegally dumped material at Les Mielles. In 2012, 5,640litres of general waste 11,411ltrs of green waste, 1,381ltrs of ash and 420ltrs of rubble was dumped at Les Mielles instead of being correctly disposed …show more content…
In2012 many hurdles were erected either side of the paths running through the nature reserve in order to ensure people remain on the paths to prevent destruction of habitats. However, many of these were broken or removed, resulting in the breeding sites of the Green Lizard and the Agile Frog being disturbed. Similarily, on the heathland at Les Landes, deep rutting has occurred on and off the footpaths, which increases erosion. This damage takes many years to heal. There is also an erosion issue on Les Blanches Banques due to activities such as sand surfing, which in turn create sand blow outs resulting in a net loss of vegetation cover and sand from the area.
Natural Threats: There are also predation pressures. Ducks and palmate newts eat the frogspawn. Birds, cats and feral-ferrets eat adult frogs. Introduced exotics - Common frogs (Rana temporaria) and mainland European green frogs (Rana lessonae/ esculenta), which have recently become established in Jersey compete with, and predate on, agile frogs. Small populations of both species due to the population ‘bottle-neck’ can also affect the wellbeing of both species. Issues include ‘genetic risk factors’ such as interbreeding depression. This can reduce the biological fitness of the species, which refers to a species’ ability to reproduce and survive.
Conservation
The damage caused by fires this year was at its lowest point in four years, with only 1,140m2 of gorse being destroyed in two small fires. However, in previous years the damage from fires has resulted in substantial areas of the nature reserve being destroyed. This destroys the habitats of the wildlife found in the dunes and can take long periods of time to regrow and be inhabitable again. One factor that has played a big role in the depletion of the number of Agile Frogs has been pollution. In 2012 two pollution events occurred. The first, a pond in the SSI became contaminated with fuel, which was one of the major breeding sites of the Agile frog and badly affected the water quality. The second, 10 barrels full of oils and solvents were dumped on the site, leaking into the surrounding area. Furthermore, the Transport and Technical Services ranger team have been clearing away huge quantities of general waste and illegally dumped material at Les Mielles. In 2012, 5,640litres of general waste 11,411ltrs of green waste, 1,381ltrs of ash and 420ltrs of rubble was dumped at Les Mielles instead of being correctly disposed …show more content…
In2012 many hurdles were erected either side of the paths running through the nature reserve in order to ensure people remain on the paths to prevent destruction of habitats. However, many of these were broken or removed, resulting in the breeding sites of the Green Lizard and the Agile Frog being disturbed. Similarily, on the heathland at Les Landes, deep rutting has occurred on and off the footpaths, which increases erosion. This damage takes many years to heal. There is also an erosion issue on Les Blanches Banques due to activities such as sand surfing, which in turn create sand blow outs resulting in a net loss of vegetation cover and sand from the area.
Natural Threats: There are also predation pressures. Ducks and palmate newts eat the frogspawn. Birds, cats and feral-ferrets eat adult frogs. Introduced exotics - Common frogs (Rana temporaria) and mainland European green frogs (Rana lessonae/ esculenta), which have recently become established in Jersey compete with, and predate on, agile frogs. Small populations of both species due to the population ‘bottle-neck’ can also affect the wellbeing of both species. Issues include ‘genetic risk factors’ such as interbreeding depression. This can reduce the biological fitness of the species, which refers to a species’ ability to reproduce and survive.
Conservation