(Editor’s note: Alison Green, senior marine biologist at The Nature Conservancy, is spending the next two weeks diving and exploring Palmyra Atoll as part of the first marine assessment of the atoll. Follow her posts from Palmyra on Cool Green Science…and learn more about the expedition.)
The tropical oceans of the world comprise four major biogeographic regions: the Indo-West Pacific, Eastern Pacific, Western Atlantic and Eastern Atlantic. These four regions show considerable variation in species composition and diversity, resulting from differences in their evolutionary history and oceanographic conditions.
Of these, the Indo-West Pacific, where Palmyra is located, is by far the most diverse.
This region is very large, and comprised of several sub-regions where endemic (locally restricted) species can be found. One of these is the Central Pacific, which includes Palmyra.
Consequently, the reef fishes of Palmyra are a mixture of widely distributed Indo-Pacific species, such as the Redfin Butterflyfish (Chaetodon lunulatus), and species that are endemic to the Central Pacific.
As a self-confessed fish geek (the marine version of an avid bird watcher), I’ve spent many hours making species lists of reef fishes, and looking for new species to add to my lifetime list wherever I go. So one of the reasons I was excited about coming to Palmyra was to see species that I haven’t seen before.
Palmyra did not disappoint me, and I have added nine fish species to my lifetime list. Some of which are very colorful and beautiful such as the Golden Gregory (Stegastes aureus), while others have more drab coloration such as the Central Pacific Coris (Coris centralis) and are not nearly as glamorous. But it’s all the same to me — I love to see them all.
(Images: Redfin Butterflyfish, Palmyra (top) and Golden Gregory, Palmyra (bottom). Credit: Kydd Pollock/TNC.)