Table 1. Search effort required to make statement of probability of absence (extinction) for eight species of Hawaiian forest birds. All have been suggested for delisting by the U.S. Fish and Wildlife Service and were reported as presumed extinct in a 2003–2004 report to Congress (U.S. Fish and Wildlife Service 2006b).

            Number of point counts required for three levels of confidence in absence
Species Island Range (km2) Effective detection distance (m) Effective area surveyed / station (ha) Number of point counts done 0.90 0.95 0.99
Lesser ’Akialoa Hemignathus ellisianus obscurus Hawaii 1045 32 0.32 2319 275 462 300 800 320 128
Moloka’i Creeper Paroreomyza flammea Molokai 573 28 0.25 131 197 280 215 427 229 270
Kamao Myadestes myadestinus Kauai 25 60 1.13 140 1875 2047 2179
Oloma’o M. lanaiensis Molokai 16 23 0.17 120 8165 8916 9488
Kaua’i O’o Moho braccatus Kauai 25 66 1.37 140 1550 1692 1801
Greater ’Akialoa Hemignathus ellisianus procerus Kauai 25 32 0.32 140 6590 7197 7659
O’u Psittirostra psittacea Hawaii 145 66 1.37 357 8986 9812 10 443

Nukupu’u Hemignathus lucidus		 Kauai
Kauai		 25
25		 66
39		 1.37
0.48		 140
140		 1550
4437		 1692
4845		 1801
5157

Maui Akepa Loxops coccineus		 Maui
Maui		 7
23		 39
34		 0.48
0.36		 35
84		 1243
5371		 1357
5865		 1444
6242