|Mysterious toad deaths in Cornwall|
|Written by ARG UK|
|Wednesday, 07 March 2012 13:08|
ARG UK was contacted recently about the mass mortality of toads and frogs around spawning ponds in Cornwall. Devon Reptile & Amphibian Group member Melanie Pritchard was greeted with the gruesome find of lots of toad and frog bodies by the side of the pond she was surveying. Individual toads and frogs were left in pieces in some places while in other areas toads were left piled in heaps of dead and dying bodies.
At first Melanie was concerned about the possibility of disease and made contact with the ARG UK panel for advice. Several members of the panel reviewed the evidence contained in the photos and came to the conclusion that this was the work of a predator, most likely otter, mink, rat or heron. Melanie will be checking for further signs of the culprit.
The grouping of large numbers of amphibians in or approaching the breeding pond at spawning time provide an easy food source for their predators. The piling up of bodies around the pond edge is either where the animal sets up a feeding station catching prey and then taking it to the same spot to eat or it could be the behaviour of caching food items when it is plentiful.
Although toads have toxins in their skin and paratoid glands which secrete a milky substance over the skin to make them taste bad to deter predators, some animals have learnt that toads can be eaten from the belly which does not have the toxins. Often toads which have been eaten by otters seem to have been turned inside out as the otter flips them over and eats the flesh and spawn from the underside of the toad. Frogs do not have such toxins and therefore are also defenceless against these predators. Despite this, sufficient frogs survived to spawn in the pond.
Frog Spawn Clumps and Toad Spawn Strings can be reported to the Big Spawn Count 2012
If you have seen any frog or toad deaths then please do let us know about them in the Record Pool sightings card