Rockhopper penguin is one of the world’s most numerous penguin populations, it is estimated that the population declined by some 30 percent over the final 30 years of the 20th century. The cause of this decline is mainly unknown, but scientists have speculated that humans are involved, mostly by commercial overfishing, oil exploitation, and pollution. Recent research has shown that rockhopper penguin population declines with changes in ocean surface temperature, indicating a direct impact from climate change. These activities have depleted much of the rockhopper penguin’s food supply and raised the sea surface temperatures, and because this species is geographically isolated to
Fitcher's Bird as sign of disobedience"). Among Grimm's fairy tales, the forbidden door features here and in "Mary's Child" (AT 710), as have been remarked in the notes to that tale. Some European variants of the ballad "Lady Isabel and the Elf Knight", Child ballad 4, closely resemble this tale. Fitcher's Bird "Fitcher's Bird" (German: "Fitchers Vogel") is a German fairy tale collected by the Brothers Grimm, tale number 46. It is Aarne-Thompson type 311, the heroine rescues herself and her sisters. Another tale of this type is "How the Devil Married Three Sisters". The Brothers Grimm noted its close similarity to