Highly suspect piece from Living Green. To begin with Antarctic sea ice is increasing, not decreasing and this has been the case for the last 50 years or so. Moreover the Antarctic Peninsula is not at all representative and the portion under discussion is not even in the Antarctic but protrudes north of the Antarctic Circle into the Southern Ocean.
Three penguin species that share the Western Antarctic Peninsula for breeding grounds have been affected in different ways by the higher temperatures brought on by global warming, according to Stony Brook University Ecology and Evolution Assistant Professor Heather Lynch and colleagues.
The work by Lynch and her team is contained in three papers that have been published online in Polar Biology, Ecology and Marine Ecology Progress Series (MEPS).
Lynch and her colleagues used a combination of field work and, increasingly, satellite imagery to track colonies of three penguin species – Adélie, chinstrap and gentoo. The Adélie and chinstrap migrate to the peninsula to breed, while the gentoo are year-round residents. (Penguins are only found in the Antarctic, and not in the Arctic.)
The Antarctic is considered one of the world’s most rapidly warming regions. Warmer temperatures move up the breeding cycle, causing the penguins to lay their eggs earlier. The resident gentoo population is able to adapt more quickly and advance their “clutch initiation” by almost twice as much as the other species. Lynch believes this may allow them to better compete for the best nesting space. The Adélie and chinstrap are unaware of the local conditions until they arrive to breed and have not been able to advance their breeding cycles as rapidly.
In addition, the gentoo prefer areas with less sea ice, and have been able to migrate further south into the Antarctic as the sea ice shrinks. The chinstrap and Adélie species rely more heavily on the abundance of Antarctic krill, which require sea ice for their lifecycle.
The result – the gentoo numbers are increasing while the other two species have noticeably dwindling populations on the Antarctic Peninsula.