HAWAIIAN DUCK (KOLOA) Anas wyvilliana (Sclater) 



Order: ANSERIFORMES Family: ANATIDAE 



Distinguishing characteristics : Small, teal-sized duck, streaked brown and buff. 

 Color similar to a Mexican duck in male, but with somewhat paler body and darker head. 

 Female similar in color to a female mallard. 



Present distribution : Resident on island of Kauai, Hawaii, where it inhabits coastal 

 lagoons, marshes and mountain streams. Reintroduced experimentally on Oahu and 

 Hawaii . 



Former distribution : Resident on the main islands of the Hawaiian group except Lanai 

 and Kahoolawe . 



Status : Much reduced from former numbers . 



Estimated numbers : State Division of Fish and Game personnel estimate 3,000. 

 (Swedberg 1967) . 



Breeding rate in the wild : Clutch size averages 7.8 eggs. 



Reasons for decline : Changes in agricultural practices (great decline in taro and rice 

 acreages) and destruction of other wetlands, indiscriminate shooting. Predation by 

 mongooses, (except Kauai) rats, cats, dogs, and pigs, particularly on nests. 



Protective measures already taken : Protected by Federal and State law . Not hunted 

 since 1930. Introduction of mongoose on Kauai prevented. Hawaii Division of Fish and 

 Game has completed a special study of their ecology and conducted a propagation program 

 with funds from the World Wildlife Fund. Many in aviaries in the United States and Europe 

 are available for stocking purposes. In 1968, 32 were liberated in Kawainui Swamp, 

 Oahu and 52 in Kohala Mountains, Hawaii. Some breeding by latter birds has occurred. 

 Critical habitats identified , reasons for decline detailed and action program recommended 

 in booklet published jointly by Bureau of Sport Fisheries and Wildlife and Hawaii Division 

 of Fish and Game. Acquisition of key area at Hanalei as a national wildlife refuge. 

 Negotiations in progress for other key areas on Kauai . 



Measures proposed : Preservation of natural environment including establishment of 

 needed refuges. Control predators where needed. Reintroduction into former range. 

 Increase law enforcement effort. Continue ecological and life history research. Surveillance 

 for chemical contamination and other such environmental pollution. 



Number in captivity : Low hundreds distributed a;nong various zoos and aviaries . 



Breeding potential in captivity : Good . 



References : 



Hawaii Division of Fish and Game Administrative Reports. 



Munro, G. C. 1960. Birds of Hawaii . Charles E. TuttleCo., Rutland, Vermont, 

 and Tokyo, Japan. 



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