The Animal Protection Group notes that over 60 dolphins have been found dead, but signs on the carcasses show that half of them died before the oil spill.
Most of the dolphins that died from oil injuries "died within the first ten days after the accident", according to the group. The dolphins belong to the endangered Azov species.
The Kerch Strait separates the Russian-occupied Crimean Peninsula and the Russian region of Krasnodar and is the connection between the Black Sea and the Sea of Azov, and has a strategic and crucial significance in the Russian invasion war in Ukraine.
Russia's President Vladimir Putin has called the accident an "ecological catastrophe". Ukraine is demanding sanctions against Russian oil tankers, often old ones, that travel through the strait.
The severe oil spill has forced local authorities to declare a state of emergency in several regions. In recent days, a crisis situation has also been declared along the shores of the city of Sevastopol, which is 25 miles from the Kerch Strait.
