Southern rockhopper penguin first noted. Their breeding colonies are located from sea-level to cliff-tops and sometimes inland. Their breeding season starts in September and ends in November. Two eggs are laid but only one is usually incubated. Incubation lasts 35 days and their chicks are brooded for 26 days. Foraging behavior in penguins varies across ecological conditions. Rockhopper penguins are present at a variety of climates and locations; Amsterdam Island's (AMS) subtropical waters, Kerguelen Archipelago's (KER) subarctic coastal waters, and Crozet Archipelago's (CRO) subantarctic coastal waters. Due to the species plasticity they are able to express different strategies and foraging behaviors depending on
Bird-of-paradise lek-type mating system. Others, such as the "Cicinnurus" and "Parotia" species, have highly ritualised mating dances. Males are polygamous in the sexually dimorphic species, but monogamous in at least some of the monomorphic species. Hybridisation is frequent in these birds, suggesting the polygamous species of bird of paradise are very closely related despite being in different genera. Many hybrids have been described as new species, and doubt remains regarding whether some forms, such as Rothschild's lobe-billed bird of paradise, are valid. Birds-of-paradise build their nests from soft materials, such as leaves, ferns, and vine tendrils, typically placed in a tree