Similar practices are still in use on some islands, as on Chios. However, today, as the migratory birds face growing problems, this massive persecution is nothing but an additional and unjustified burden. According to the same source, the total catastrophe was prevented by the sudden appearance of vast flocks of a bird that devoured the menace, a miracle attributed to St. Athanasios. Having spent the winter in the Indian sub-continent, it migrates westwards as far as the steppes around the Black Sea. Occasionally, it moves in large flocks further west, breeding wherever conditions are suitable.
Locust swarms are often the cause of such unexpected appearances.
It is therefore a matter of debate as to why several mainland species don't occur on the islands. The reason for this absence is that the islands don't provide enough space and suitable habitats for all bird species. Y. Roussopoulos Rocky coast on Faradonisia islets, Leros. T he open sea is the haunt of the seabirds, like the Levantine Shearwater, which move over great distances following the shoals of fish. Coastal waters are shallow so fishing is easier here.