Who killed 20 plus frogs and toads

Who killed 20 plus frogs and toads

Observation - Who killed 20 plus frogs and toads - UK and Ireland. Description: There are always frogs and toads in this loch at this time of year; however, this is the first time we have found dead ones. All the dead ones we saw were within 2-3 metres of the grassy mound shown in photograph 1. There were numerous live frogs in the l

Identification is for the live toads in photographs 8 & 9.
There are always frogs and toads around the loch at this time of year; however, this is the first time we have found dead ones. All the dead ones we saw were within 2-3 metres of the grassy mound shown in photograph 1. There were numerous live frogs and toads (photos 8 & 9) in the loch. I would like to know what killed the frogs/toads and whether there are toad remains too?