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
What Bird is That? friends, together with the succinct but compendious descriptive information, will place within easy reach of the bird lover, a most valuable "vade mecum" of bird and bush lore for out of doors as well as a thing of beauty for the library." Cayley’s aim in creating this work was to make available a book that would encourage and help people to learn about and appreciate Australia’s remarkable and unique bird life. He saw and responded to a need for a simple book that was accessible to the non-specialist birdwatcher. Each species was illustrated in colour and the birds were organised