Birds of the Hawaiian Islands 



The Hawaiian Archipelago includes such outlying islets as Laysan, which is the 

 scene of the sea-bird group that represents this fauna in our hall. The habitats are 

 varied — sandy islets, larger islands with sea beaches, bare lava flows, hot dry deserts, 

 fertile valleys, marshy lowlands, grassy hills, wet forests, and bare snow-capped peaks. 

 Isolated in the North Pacific far from any continent the islands have a truly oceanic 

 fauna; all the animals arrived by travelling overseas, the land animals as waifs and 

 strays — accidental colonists. 



These colonists, once established in the isolation of their new island home, evolved 

 into new forms, colonized other islands and evolved still more forms; so the process 

 went on. The length of time the birds have been isolated is reflected in the degree of 

 distinctiveness they have achieved. There is one endemic family (honey creepers, with 

 about 45 species), obviously representing the oldest colonist; there is one endemic 

 genus each of rail, honeyeater, thrush, flycatcher and goose; three endemic species — a 

 crow, a hawk, and a duck; and four endemic subspecies- an owl, a stilt, a gallinule, 

 and a coot. The most recent arrival is probably the night heron, which is still quite the 

 same as the form on the mainland. 



Colonization from across a wide sea has been difficult and has occurred only at long 

 intervals. Thus the numbers of birds known in the archipelago is small; there are only 

 96 resident species (plus 8 regular migrants, 34 accidentals or of casual occurrence, 

 and 94 introduced species). To consider the amount of endemism in another way, 

 77 of the 96 birds of regular occurrence are endemic, that is, found nowhere else. 



From a study of the endemic birds, Mayr concludes there had been fourteen differ- 

 ent colonizations. By studying the relationships of these birds it was possible to deter- 

 mine whence their ancestors, the original colonists, tame; in eleven of the coloniza- 

 tions they came from America and only in two from Polynesia. Though the islands are 

 in the Pacific, and the native people Polynesians, it appears the bird fauna must be 

 grouped as predominantly North American. 



The sea birds, mostly of more widespread distribution in the Pacific, will be dis- 

 cussed in connection with the Laysan Island exhibit below. The regular migrants, in- 

 cluding three ducks and five shore birds, and the casuals and strays (thirty-four species) 

 will not be discussed further. The endemic mountain birds and the introduced 

 species will have a further word here. 



MOUNTAIN FOREST BIRDS 



In the mountain forests there are from 50 to 55 native perching birds. They include 

 a crow, 6 thrushes, 3 flycatchers, 5 honeyeaters, and between 40 and 45 species of 

 native honey creepers belonging to the peculiar Hawaiian family Drepaniidae. 



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