Pelagic Cephalopods — P earcy 
263 
North America, was found in several otter trawl 
collections where the depth was 100 m or less, 
but was absent from midwater trawl collections. 
Rossia pacifica, another myopsid, was taken 
mainly in otter trawl collections, as was the 
large (DML 200 mm) Gonatus magister. Go- 
natus anonychus was collected only with a dip 
net under night lights (Pearcy and Voss, 1963). 
The relative abundance of the cephalopods 
captured by midwater trawling from all sta- 
tions and depths is shown in Figure 1. Gonatus 
fabricii comprised about 38 percent of the total 
catch. A group consisting of larval and juve- 
nile individuals of the genus Gonatus, but 
without sufficient differentiation of hooks for 
specific identification, was next in numerical 
importance. At least three separate species of 
Gonatus may be represented (Table 1) but, 
judging from the relative abundance of larger 
gonatids, most are probably G. fabricii. 
Geographic Distribution 
Little difference in the species composition 
of cephalopods was noted among the latitudes. 
Gonatus fabricii, G. spp., and Abraliopsis dom- 
inated the midwater trawl collections at nearly 
all series of stations. Pelagic cephalopods, as 
well as mesopelagic fishes (Pearcy, 1964), 
were rare at the inshore stations off Newport, 
where the depth of water was 300 m or less. 
Depth Distribution 
The number of common squid captured per 
hour of towing appeared greater in tows to 
200 m than in deeper tows; this was particu- 
larly true of Gonatus spp., Chiroteuthis veranyi, 
and Abraliopsis sp. (Table 2 A). Since an 
opening and closing device was not used on 
the trawl, some of the animals found in tows 
to 500 and 1000 m were probably caught while 
the trawl sampled through the upper 200 m. 
Such differences in catches suggest that the 
four common squids are largely epipelagic in 
distribution during the night, when most of 
the 0-200 m collections were made. Compari- 
sons of day and night catches of the two most 
abundant squids, G. fabricii and Abraliopsis sp., 
show that highest catches were made during 
the night in tows to 200 m depth but during 
the day in tows to 500 m (Table 2C). This 
PERCENTAGE OF TOTAL CATCH 
0 10 20 30 
I I i i 
Gonatus fabricii 
/// /////// 
7 / 7 "// "////// 
*7777777777, 
Gonatus spp. 
Abraliopsis sp. 
1/ ’///////////;'//////////,', //I 
Chiroteuthis veranyi 
1 . TZZZZZZZZZZZA 
Japetella heathi 
V777A 
Gonatopsis borealis 
cm 
Octopodidae 
□ 
Taonius pavo 
m 
Gonatus magister 
□ 
Ga/iteuthis armata 
□ 
Octopoteuthis sicu/a 
□ 
Onychoteuthis banks! 
q 
Rossia pacifica 
d 
Vampyroteuthis inferna/is 
D 
Cranchia scabra 
0 
Meteagroteuthis ho/yei 
0 
FIG. 1. The relative abundance of pelagic cephalopods found in midwater trawl collections off Oregon. 
