132 
Fishery Bulletin 115(2) 
Table 1 
Names and number of sightings of cetacean species observed in the U.S. Hawaiian Islands Exclusive Economic Zone during 
the Hawaiian Islands Cetacean and Ecosystem Assessment Survey in 2010. Stock names refer to those used in the National 
Marine Fisheries Service stock assessment reports (Carretta et ah, 2014). Ntot is the number of systematic, nonsystematic, 
and off-effort sightings (n=398); Nsys is the number of sightings made while on systematic effort in Beaufort sea states 0-6 
(n=211); and Nest is the number of sightings made while on systematic effort that were within the analytical truncation 
distance and, therefore, used in the abundance estimation (n=177). The abundance of some species could not be estimated 
(N/A). NWHI=Northwestern Hawaiian Islands. 
Common name 
Scientific name 
Stock name 
Ntot 
Nsys 
Nest 
Pantropical spotted dolphin 
Stenella attenuata 
Pelagic 
12 
11 
10 
Striped dolphin 
Stenella coeruleoalba 
Hawaii 
25 
20 
18 
Spinner dolphin 
Stenella longirostris 
Pelagic 
4 
0 
N/A 
Rough-toothed dolphin 
Steno bredanensis 
Hawaii 
24 
8 
8 
Bottlenose dolphin 
Tursiops truncatus 
Pelagic 
19 
7 
6 
Risso’s dolphin 
Grampus griseus 
Hawaii 
10 
9 
9 
Fraser’s dolphin 
Lagenodelphis hosei 
Hawaii 
4 
3 
3 
Melon-headed whale 
Peponocephala electra 
Hawaiian Islands 
1 
1 
1 
Pygmy killer whale 
Feresa attenuata 
Hawaii 
5 
4 
4 
False killer whale' 
Pseudorca crassidens 
Pelagic and NWHI 
14 
6 
6 
Short-finned pilot whale 
Globicephala macrorhynchus 
Hawaii 
36 
15 
11 
Killer whale 
Orcinus area 
Hawaii 
1 
1 
1 
Sperm whale 
Physeter macrocephalus 
Hawaii 
41 
26 
23 
Dwarf sperm whale 
Kogia sima 
Hawaii 
1 
0 
N/A 
Unidentified Kogia 
Kogia sirna/breviceps 
N/A 
1 
0 
N/A 
Blainville’s beaked whale 
Mesoplodon densirostris 
Hawaii 
2 
1 
1 
Cuvier’s beaked wbale 
Ziphius cavirostris 
Hawaii 
23 
2 
2 
Longman’s beaked whale 
Indopacetus pacificus 
Hawaii 
3 
3 
3 
Unidentified Mesoplodon 
Mesoplodon spp. 
N/A 
10 
6 
6 
Unidentified beaked whale 
Ziphiid whale 
N/A 
27 
4 
3 
Minke whale 
Balaenoptera acutorostrata 
Hawaii 
1 
0 
N/A 
Bryde’s whale 
Balaenoptera edeni 
Hawaii 
32 
19 
19 
Sei whale 
Balaenoptera borealis 
Hawaii 
2 
2 
2 
Fin whale 
Balaenoptera physalus 
Hawaii 
2 
1 
1 
Blue whale 
Balaenoptera musculus 
Western North Pacific 
1 
1 
1 
Humpback whale 
Megaptera novaeangliae 
Central North Pacific 
1 
1 
N/A 
Sei or Bryde’s whale 
Balaenoptera borealis/edeni 
N/A 
12 
9 
8 
Unidentified rorqual 
Balaenopterid whale 
N/A 
11 
9 
6 
Unidentified small dolphin 
Small delphinid 
N/A 
17 
10 
6 
Unidentified medium dolphin 
Medium delphinid 
N/A 
6 
3 
1 
Unidentified large dolphin 
Large delphinid 
N/A 
3 
2 
2 
Unidentified dolphin 
Delphinid 
N/A 
19 
9 
6 
Unidentified small whale 
Small whale or large dolphin 
N/A 
1 
1 
1 
Unidentified large whale 
Large baleen or sperm whale 
N/A 
8 
6 
N/A 
Unidentified whale 
Small or large whale 
N/A 
3 
2 
2 
Unidentified cetacean 
Cetacean 
N/A 
16 
9 
7 
'Abundance estimation of the pelagic and NWHI stocks of false killer whales is covered in Bradford et al. (2014, 2015) and was 
not considered further in this study. 
eludes the total number of individuals in mixed-species 
groups, treated as a continuous variable), cruise num¬ 
ber (the number assigned to each survey on a given 
ship in a given year, treated as a categorical variable), 
ship (the survey ship, treated as a categorical variable), 
year (the survey year, treated as a categorical variable), 
and species (the most abundant species v^ithin a group, 
treated as a categorical variable). The categorical co¬ 
variates were tested only if there were at least 10 ob¬ 
servations for each factor level. 
To correct for the tendency of individual observers 
to over- or underestimate group size, correction factors 
were applied to the “best” estimates of sighting group 
size made by observers who were calibrated during 
previous SWFSC surveys by a comparison of observer 
group size estimates and counts of the same cetacean 
groups from aerial photographs (Gerrodette and For- 
cada, 2005). An indirect regression-based calibration 
method was used to calibrate noncalibrated observers 
in relation to the calibrated observers (Barlow, 1995; 
