The Humane Society claims hundreds of badgers may have drowned in the floods that devastated the Somerset Levels earlier this year.
The animal protection organisation makes the claim in support of its efforts to prevent the badger cull re-starting. From this week the pilot culls in the Gloucestershire and Somerset cull zones can technically begin again.
Mark Jones, the Humane Society UK's executive director said: "Both Somerset and Gloucestershire were badly affected by adverse weather conditions, including severe flooding and freezing temperatures only weeks after badgers in those areas had already endured shooting during the Government's culls.
"We know that the bodies of drowned badgers were reported, including by farmers, and a few lucky but exhausted badgers were rescued. We fear these few may have been the tip of the iceberg. It is quite possible that hundreds of badgers in the local area could have died.
"Notwithstanding our contention that badger culling is unnecessary, inhumane and ineffective as a means of controlling TB in cattle, it would be irresponsible of Defra to allow further culling to take place without first carrying out thorough surveys."