The Abrolhos Region, spanning 56,000 square km, is a mosaic of marine and coastal ecosystems that encompasses the largest reef area and the highest marine biodiversity in the southern Atlantic. The Abrolhos Bank serves as the main breeding ground for humpback whales in the western South Atlantic Ocean and constitutes the only offshore site along the distribution of the guiana dolphin, and is also home to the rough-toothed dolphin, bottlenose dolphin as well as three IUCN Red-listed marine turtle species: the endangered green (Chelonia mydas) and loggerhead (Caretta caretta) turtles, and the critically endangered hawksbill turtle (Eretmochelys imbricata). The area experiences threats from severe overfishing, oil and gas drilling, tourism and urban development, but progress is in the works. There are currently four federally-protected marine protected areas in the region, and Conservation International has developed a proposal to expand the MPA network in the Abrolhos Seascape by expanding the Abrolhos National Marine Park and creating two new marine protected areas.