Danube bleak branched rays while the anal fin has fifteen to nineteen. This fish is morphologically quite variable which may be due to local adaptations to various habitats but is more likely to be due to several species being involved. The Danube bleak occurs in slow flowing stretches of rivers flowing into the Black Sea and the Caspian Sea and in the Aral Sea basin, in Alpine rivers among others. It is a migratory fish, spawning in the headwaters of the rivers and then moving down to the lower parts, estuaries and brackish areas of sea. These migratory patterns have been disrupted
Cryptid whale Another argued hypothesis is that that pod was part of an inbred population, which led to the mutation. Another possibility is that Quoy and Gaimard observed specimens which were neither deformed nor members of an unknown species or population, but rather mistaken identification of a pair of beaked whales that, by perspective, appeared to be one single creature. The high-finned sperm whale, or the high-finned cachalot, is an alleged variant or relative of the known sperm whale, "Physeter macrocephalus", with an unusually tall dorsal fin from the North Atlantic. The physician Sir Robert Sibbald, in 1687, described an alleged stranded