Northern rockhopper penguin the ship broke up, leaving an oil slick that surrounded the island, threatening its population of rockhopper penguins. Nightingale Island has no fresh water, so the penguins were transported to Tristan da Cunha for cleaning. Northern rockhopper penguin Recent studies show the northern rockhopper penguin, Moseley's rockhopper penguin, or Moseley's penguin ("Eudyptes moseleyi") distinct from the southern rockhopper penguin. A study published in 2009 showed that the population of the northern rockhopper had declined by 90% since the 1950s. For this reason, the northern rockhopper penguin is classified as endangered. The rockhopper penguins have been considered to consist of two
Rockhopper Exploration in production licences PL023, PL024, PL032 and PL033 covering approximately 3800 km. In 2005 it farmed into licences PL003 and PL004 operated by Desire Petroleum plc. In 2011, Rockhopper increased its share of PL004b from 7.5% to 60.0% and in PL004c from 7.5% to 25.0%. Licence PL004b contains an extension to the Sea Lion field as well as the Beverley, Casper and Casper South discoveries. The Rockhopper board comprises eight directors; a non-executive chairman, three executive directors and four non-executive directors, one of whom acts as senior independent director. Four of the non-executive directors are considered to be independent. The