Nippon
Suisan
Gakkaishi
On the
54(7),
Flying
1167-1174 (1988)
Behavior
Observed
of Neon
in the Central
Flying
and
Squid
Ommastrephes
Northwestern
North
bartrami
Pacific
Mamoru Murata*
(ReceivedDecember12, 1987)
The
region
the
R/V
under
from
the
14-18cm)
night,
by
and
in
day
that
from
a distance
and
Judging
mantle
they
squid
172•‹W
period
squid.
18cm
flying
and
flew
both
flying
their
160•‹E
in
direction
about
and
of neon
long.
length:
same
purpleback
day
behavior
Omi-Maru
mantle
the
flying
between
length
have
by
from
of
was
along
observed
lat.
July
to
10-20m
at
The
form
a gliding-type
Hokkaido
守:北
of
of squid
it
is
squid
flying
10-300
1-2
in
m
behavior
on
sea
fish,
in
that
of
individuals
surface
flying
surface
smaller
the
board
(estimated
resembled
the
near
like
the
closely
that
mainly
subtropical
squids
above
flight
beleived
live
in the
17-24•Ž),
of
the
mainly
sea,
to
by
escape
enemies.
Several species of the family Ommastrephidae
are known to show a leaping, or flying behavior.1-3
Arata1) reported on the flying behavior of neon
flying squid, Ommastrephes bartrami, or webbed
flying squid, O. calori, observed off the Atlantic
coast of North
America.
Akimushkin2)
and
Clarke3) also referred to the flying behavior of
these species, and reported that the name "flying
squid" was applied to O. bartrami because of this
behavior.
It was also reported4) that purpleback
flying squid Sthenoteuthis oualaniensis was observed flying over the sea surface off the Pacific
coast of the southern Japan.
Moreover, Azuma5) inferred from photographs
of purpleback
flying squid in flight in the Indian Ocean that their
arms and instant membranes would play a vital
role in flight.
However, none of the reports have included
such information as the size of the squids observed
flying, their numbers, flight condition, and associated oceanographic and weather conditions.
Although the neon flying squid stock is quite
considerable in the northern part of the North
Pacific,6) and yields an estimated 182,000 tonnes
per year (1982-86 average) to Japan's squid gillnet
and jigging fisheries,7) virtually no information
has yet been reported on the flying behavior of this
species from this area.
During a survey on the distribution of squid in
the North Pacific in 1984, 8 flights of neon flying
squid were observed.
The results of the observations and some considerations on the relationship
*
Roughly
a height
results,
flying
locations
temperature:
1984.
of
these
8 different
(surface
August,
night.
neon
at
37•‹N
Regional
Fisheries
海 道 区 水 産 研 究 所).
Research
Laboratory
between
flying
squid,
the
and
the
sented
behavior
possible
swimming
and
of
the
depths
of
the
length
of
flight
the
behavior,
squid,
are
pre-
here.
Materials
The
of
survey
neon
on
the
was
August
3,
Maru
of
High
School
length).
using
cruise
and
shown
in
Squid
Fig.
stations
before
morning
hours
sighting
survey
day
sunset
on
Kushiro,
172•‹W;
To
different
operated
are
and
in
sizes
Kushiro,
long.
the
used
as
follows:
Hokkaido,
The
out
sunrise
and
this
and
report
occurred
at
37•‹N,
long.
1913-1916,
re-
158-175•‹E.
catch
was
17
early
carried
in
lat.
and
37•‹N,
the
day.
sunset
at
by
at
Hawaii,
given
0447-0449
bias
next
was
times
Sunrise
gillnet
set
Honolulu,
All
lat.
stations
in
the
respectively,
size
, Katsurakoi,
for
items,
22
between
between
at
the
of
daytime
run
at
mesh
overall
station
were
retrieved
mammals
the
and
at
gillnets
and
for
1819,
avoid
of
survey
(0300-0600)
times.
selectivity,
Omi-
Fisheries
in
locality
while
sunset,
the
spectively,
and
vessel
47.10m
principal
were
in
and
1
Prefectural
GT,
Hokkaido.
local
0341
North
July
research
track,
(2000-2300);
each
marine
1.
jiggings
night
the
the
on
between
Yamaguchi
The
abundance
as
northwestern
out
(417.47
operations,
well
and
carried
the
and
as
central
1984,
Methods
distribution
squid,
in
Pacific,
and
the
flying
mammals,
are
body
causes
from
mesh-size
constructed
33,
37,
085,
of
42,
Japan
48,
13
55,
(村 田
1168
Murata
63, 72, 82, 93, 106, 121, 138 and
157mm.
Results
Flight
Observations
During
was
the
survey,
observed
23,
1984
in
(Fig.
1)
1.
The
Table
flight
of
squid
neon
2 in
yuki
Yamawaki)
3-7
in
on
1)
of
survey
lat,
0700
became
being
retrieved.
10-20m
the
(range
in
length,
at
the
of
the
this
to
station,
salinity,
the
had
(2)
lat.
around
0530
surface
and
as
squids
flew
of
vessel
the
surface
the
the
the
of
height
sea.
flight
in
the
squid,5)
horizontal
surface
color
flight,
of
of
the
about
of
direction,
20m
in
Three
and
the
with
in
sea,
mantle
appearing
direction
above
squids
the
the
fins
lasted
resembled
arms
Moreover,
andjfins
very
mesh
coincided
flight
and
the
landed
72-mm
direction
squid
the
These
the
the
at
broke
from
2m
directions.
the
26),
squids
10-20m
caught
flying
4;
1)
20-30
of
The
pleback
19.2•‹C,
(Station
retrieved.
were
In
was
being
2).
wind
of
surface.
Beaufort
about
was
and
3-4s.
floatline
Table
about
(Fig.
the
size
modal
sea
at
2 in
gillnet
section
about
against
airborne
a
num-
mesh
immediately
175•‹06'E
20,
distance
at
of
the
July
gillnet
a
neon
large
in
the
2 (No.
became
vessel
were
as
clear.
long.
on
in
occurred
E-SE'ly
37•‹09'N,
height
squids
caused
temperature
Observation
At
of
a
15-19cm;
surface
was
distance
size
55mm
winds,
was
gillnet,
net
at
caught
sharply
weather
a
at
squids
the
the
same
length:
flight
the
of
gillnet,
and
1)
100
The
being
48
ship
34.12•ñ;
1)
flew
the
results
(Station
as
the
The
slap
The
follows:
surface.
mantle
rolling
gillnet
ship,
about
of
dorsal
the
floatline
to
were
17cm).
after
dorsal
made
37•‹N)
Table
the
sea
gillnets
in
squids
of
that
the
I
the
angle
be
squids
out
(Nos.
during
approximately
The
above
by
7,
near
to
flying
the
July
right
estimated
with
(Hiro-
1).
as
172•‹00'W
from
at
1-2m
(Fig.
1 (No.
airborne
20-30m
lat.
were
long.
on
about
on
(Nos. 1
track
were
37-43•‹N)
37•‹03'N,
around
and
two
5 flights
(near
observations
Observation
At
At
retrieved
vessel's
observations
(lat.
flight
(1)
the
a
1) and
researcher
observed
extremity
area
the
bers
during
Table
being
the
7-
shown
one
group
another
along
these
southernmost
of
a
8 in
board
are
witnessed
in
was
squid
July
data
author
while
flying
during
relevant
squid
gillnet
neon
surveys.
All
of
the
(No.
1),
Table
of
times
present
the
Table
sighting
and
operation
when
and
flight
different
flying
jigging
others
the
eight
only
purspread
the
blended
with
dark,
while
Flying Behavior
of Neon Flying Squid
1169
Fig. 1. Track chart of the R/V Omi-Maru during July and August in 1984, and the locations (stars)
where flying behaviors of neon flying squid were observed.
Numerals and alphabets denote
No. of Stations, while numerals (1-8) in parentheses are the same as Obs. No. in Table 1.
Fig. 2. A schematic
diagram
1984 (See No. 2 in Table
the
ventral
surface
appeared
the
previous
sea
surface
floatline
in
one,
of
the
been
gillnet.
was
E-NE'ly
the
mantle
color.
The
occurred
had
temperature
winds
of
whitish
and
sharply
At
Beaufort
after
station,
the
by
the
salinity,
5,
and
the
surface
behavior
of squid
observed
on
20 July,
was cloudy.
arms
similar
whipped
this
the flying
the
flight,
immediately
17.4•Ž,
at
showing
1).
to
(3)
the
At
the
underway
Observation
around
at
proximately
33.94•ñ,
Iphis
were
weather
The
dolphins
3-5
1630
on
lat.
40
(Nos.
July
20,
37•‹01'N,
common
sighted
at
then
3-5
in
while
long.
distance
began
1)
vessel
was
173•‹06'E,
dolphins
a
Table
the
ap-
Delphinus
of
moving
about
toward
de3.6km.
the
1170
Murata
vessel
and
in
alongside.
about
three
separate
served.
flight;
were
around
50
soon
thereafter,
squids
was
in
the
the
same
dolphins.
winds,
was
cloudy.
(4)
Observation
(0700-1100),
at
flight.
At
While
near
the
station
at
was
direction
operated
about
of
the
vessel
and
Table
2.
R/V
St•@
K
squids
2).
Neon
at
at
were
as
long
was
surface
described
and
were
above
at
The
to
and
at
height
depths
surface
172•‹E
luminosa
catches
totalled
615
luminous
in
Stations
to
the
other
large
numbers
luminous
I and
of
(102
flying
outnumbered
Stations
the
squid
J.
lumious
H,
I
and
331
squid
Although
flying
J,
per
stations
squid
between
long.
station),
(1
to
few
37
squid
station).
At
(Station
but
flying
The
caught
numbers
at
neon
of
Eucleoteuthis
and
were
Flights
vicinity
37•‹N),
greatly
all
Observed
the
taken.
squid
caught
per
lat.
squid
large
164•‹
of
in
squid
and
squid
caught
lat.
flight.
the
of
of
gillnet
jigging
represent
may
(5-7m)
gear
the
be
records
Size
1)
squid
at
lat.
caught
and
(0-30m)
possible
used,
depths
by
these
of
Neon
airborne
flew
in
the
1-2m
above
close
to
of squids
by
1984.
gillnets
Date
and
Composition
The
water
in
of
jigging
37•‹00'N,
became
a height
Date•@
6 July
flying
stations,
were
dorsal
flying
squid
were
observed
flight
at
two
the
are
hook
thought
which
fishing
squid
gears.
mantle
Flying
length
taken
at
the
flying,
or
observations,
are
Squid
compositions
locations
at
the
of
where
stations
shown
in
Fig.
neon
squids
nearest
to
3.
Although a fairly wide size range (15-49cm) was
seen in the squid taken at Station 1, 83
of the
the
or jiggers
at
locations
are
Location•@
O.
Gillnets•@
1
all
flying
area
34.45•ñ,
They
the
Omi-Maru
etc.
Vicinity
species
(Table
flight
while
vessel.
reentered
Catch
the
two
squid
between
in
Table
23,
Station
at
(20cm
the
station,
the
flying
only
observed
roughly
8 in
100
the
began
jigging)
this
13-
flight
hand
At
(near
flying
appeared
salinity
caught
length:
clear.
July
at
from
surface
and
8 (No.
on
flights
neon
23,
160•‹20'E),
the
Ob-
squids
were
jig
in
stations
2,318
1)
dolphins
in
survey
observed
The
July
observed
these
that
squid
the
7.
luminous
were
salinity,
3.
observed
this
calm,
2100
20m
14
24.0•Ž,
160•‹20'E,
about
on
long.
was
being
1810
of
The
used
colora-
in
mantle
large
water.
Catches
the
and
23
164•‹18'E),
Table
a
and
squid
14cm).
Observation
relatively
were
to
this
long.
thereafter,
squids
July
21.7•Ž.
7 in
squid
dorsal
salinity,
the
Squid
162-163•‹E,
to
flying
hook
the
observed
of
Beaufort
160•‹32'E,
37•‹00'N,
around
at
at
Observation
long.
closest
7 (No.
nearest
lat.
At
sea
fog.
of
weather
was
SE'ly
sea
Soon
300
temperature
(6)
for
weather
were
was
winds
vessel.
the
into
size
in
after
steel
shape
the
The
length,
temperature,
the
1)
long.
squids
37•‹00'N,
by
long.
and
of
lat.
underway
37•‹00'N,
the
at
Observation
200
the
morning
37•‹00'N,
neon
(range
modal
cast
of
the
34.66•ñ,
and
Table
the
station
J
and
(5)
with
jigging
stainless
long.
salinity,
6 in
temperature
covered
K
lat.
the
surface
34.63•ñ,
path
flights,
4;
coincided
flight,
resembled
above.
immediately
20
flight
37•‹01'N,
21.0•Ž,
Beaufort
30-50
(Station
the
(lat.
the
observed
during
between
flight
H
6 (No.
underway
roughly
as
the
squid
2
18cm;
and
the
the
servation
At
While
was
at
10
of
by
there
occurred
case,
direction
was
E-NE'ly
each
these
temperature
and
200-300
third
During
tion
ob-
when
between
In
vessel.
path,
were
1638
the
roughly
to
their
when
at
Station
closest
surface
1633
and
general
At
172•‹30'E)
at
flying.
swimming
in
schools
second
squids,
seen
and
squid
was
the
when
were
were
them
of
first
took
minutes,
of
flights
The
squids
in
10
Ahead
37•‹00'N,
172•‹00'W
344
26
19
July
37•‹00'N,
175•‹00'E
145
H
20
July
37•‹01'N,
172•‹30'E
-
I
21
July
37•‹01'N,
168•‹40'E
J
23
July
37•‹0O'N,
164•‹18'E
K
23
July
37•‹00'N,
27
24
July
37•‹00'N,
the
locations
those
around
at
onset
Number
of
of
squid
lat.
37•‹N
squid
board
caught
bartrami•@
E.
Jiggers•@
on
jigging
Gillnets•@
282
0
6
luminosa
Jiggers
4
0
1
640
-
136
-
58
-
102
-
285
-
331
160•‹20'E
-
160
-
158•‹00'E
106
292
4
0
37
Flying Behavior
of Neon Flying Squid
catch fell within narrow range of 16-18cm. The
modal length was 17-18cm. At Station 26 and
Station H, 80% and 90%, respectively, of the
catches were squids in the 17-19cm size range;
the modal length was 18cm in both cases. At
Station J, 95% of the catch were between 16 and
18cm; the modal length was 17cm.
Similarly, at
Station K, the size range was 13-18cm; the modal
length was 14cm.
On
at
the
other
hand,
3 locations
ed
in
to
temperature
(Fig.
occurred
The
surface
locations
of
4),
all
of
there
10
4.
Horizontal
(from
behaviors
data
distribution
of
of
Japan
squid
of
Fish.
were
surface
Infor.
observed.
water
Ser.
except
in
(•Ž)
the
stations
referred
the
to
100-m
vertical
depth
as
the
and
37•‹
43•‹N,
shallower
the
vertical
the
distribution
lat.
40•‹N.
the
warm
50m,
along
of
middle
the
locations
area,
correspond
region,
of
July
where
surface
40•‹-41•‹N,
subarctic
region.10)
the
long.
temperature
37•‹-40•‹N,
survey
more
and
under
42•‹N
subtropical
subarctic
depths
lat.
lat.
and
temperatures
reached
41•‹
that
temperature
175•‹E,
with
between
of
the
in
at
the
158•‹E,
even
well
in
denote
of
lat.
appears
and
at
are
waters
from
to
salinities
or
at
generally
as
July
flights
northward
flights,
vicinity
42•‹-43•‹N
Stars
and
area
Judging
it
in
isotherms.
flights,
warm
at
distributions,
surface
squid
prominent
long.
the
the
of
period
surface
chart
between
occurred
temperature
with
13•Ž.
10•‹C
in
waters
Cent.9)).
to
5),
than
100m
boundary,
a
temperatures
the
(Fig.
However,
Fig.
was
along
respectively
rang-
18cm
to
observed
observed
to
172•‹W,10)
the
observed
the
from
salinities,
taken
chart
10-day
21-24•Ž
the
and
175•‹E.
squid
172•‹E,
16cm.
temperatures
the
to
1,
higher
11
distributional
second
distributions
and
the
the
According
than
to
the
of
ranged
from
for
where
projection
nearest
14
and
Conditions
According
Table
164•‹
lengths
from
Oceanographic
flying
long.
mantle
lengths
19849)
luminous
between
dorsal
modal
Fig. 3. Dorsal mantle length compositions of neon
flying squid caught by gillnets or by jiggers at
the locations where squid were observed in flight,
or at the stations nearest to flight observations
in July of 1984. N and N' denote numbers of
squid measured from the catches by jiggers and
by gillnets, respectively.
1171
in
1984
flying
1172
Murata
Fig.
5.
Vertical
of
1984
ST:
From
the
observed
of
subtropical
peratures
ranged
at
33.9
the
it
flights
the
to
of temperature
from
is
believed
place
within
where
the
to
and
depth
FZ:
took
17
(•Ž)
along
the
long.
that
24•Ž,
all
of
waters
10
the
TR:
to
to
be
neon
squids
Yoshida,8)
tem-
neon
salinities
temperatures
as
this
13•Ž.
1) squid
jigging
vicinity
of
bers
as
of
the
neon
squid
mately
long.
the
and
the
gillnet
for
gillnet
observed
flying
seen
20-30
175•‹E
squid
flight;
that
seen
2
was
the
in
175•‹W
in July
gillnet
in
the
about
and
the
2)
flight
Table
1),
being
retrieved,
of
the
at
3 were
cy
num-
same
size
37•‹N,
caught
and
in
were
for
modal
from
21cm;
in
37•‹N
and
squid
to
lengths
17
to
at
27cm
lat.
40•‹N,
with
from
densely
37•‹N,
and
modal
25cm
the
ranged
length
at
lengths
to
to
squid
mantle
lat.
tenden-
farther
the
18cm;
20
near
a distinct
dorsal
17
the
most
distributed
lat.
in
14,
showed
distributed
boundary
showed
be
at
19cm
of
at
Moreover,
were
subarctic
to
area
widely
42•‹N.10)
also
Namely,
14
of
regarded
population
survey
very
they
the
catches
larger
was
squid
the
were
that
near
The
and
composition
gillnet
actual
squid
revealed
north.10)
from
approxilat.
lat.
by
the
Kubodera
length
3).
catches
distributed
immediate
large
of
flying
by
mantle
caught
(Fig.
neon
squid.
report
dorsal
that
location
40•‹N.
flying
the
squid
reflecting
catches
beleived
reasons:
yielded
of
in
were
following
fishing
squid
in
flight
flights
squids
(No.
in
neon
the
flying
that
observed
flying
and
zone
from
between
the
be
Judging
The
of
175•‹E
Transitional
identified
to
the
from
boundary,
the
surface
surface
where
ranged
Subarctic
Discussion
All
158•‹E,
al. 10).
zone,
region,
34.7%,
100-m
et
Subtropical
above,
squid
from
distributions
(Murata
lat.
with
38•‹30'N,
of
with
18
and
modal
Flying Behavior
lengths
of
farthest
to
27
to
42cm
20
the
and
north
with
24cm;
at lat.
modal
while
those
41•‹30'N
lengths
caught
ranged
of
27,
of Neon Flying Squid
from
38
and
41cm.
The flying behavior of neon flying squid was
limited to the southernmost portion of the survey
area, and no flight was observed in the more northerly areas in spite of the denser distribution of
squids. The reason for this may be closely related
to the size of squid existed.
According to the
relationship
between dorsal mantle length and
body weight of neon flying squid,11) body weight
of most of the squid taken in the area near the
observed flights is calculated to be from 57 to
216g with mantle length of 13.0-19.9cm.
The
body weight of neon flying squid increases very
rapidly with the growth in mantle length, as seen
the following data: at a length of 15.5cm, weight
is 9g; at 20.5cm, 237g; at 25.5cm, 471g; and
at 30.5cm, 826g.
From the photographs
of purpleback flying
squid in flight in the Indian Ocean, Azuma5) reported that the flight was not the trajectory-type
flight exhibited by dolphins, but was rather glidingtype flight like flying fish. Azuma conjectured
that the primary lift would be provided by the
spread arms of the squid, as well as by an instant
membrane that was formed by a mucus.
The form of neon flying squid in flight, as described earlier, closely resmbled that5) of purpleback flying squid. It is therefore understood
that both neon flying squid and purpleback flying
squid show similar gliding-type flight behavior.
A thin membrane, referred to as the protective
membrane, is well developed on a pair of the third
arms of neon flying squid.12) This membrane
is thought to play an important role in flight.
However, judging from the structure of the body
parts, there seems to be relatively little lifting
power during flight. For this reason, it is assumed that the flying behavior of neon flying squid
is very closely related to the body weight.
Although no report on the relationship
between
flying behavior and body weight is available,
Arata1) reported that a squid (neon flying squid,
or webbed flying squid) with a dorsal mantle length
of 15.2cm flew a distance of 12-15m at a height
of 1.8-2.4m above the sea surface.
In spite of the fact that neon flying squid is one
of the commercially important species of the northern North Pacific, no observation has been re*
1173
ported previously on its flight behavior.* The
reason may be that the commercial fisheries are
exploiting squid that are much larger than those
that undertake these flights. In squid jigging and
gillnet fisheries, monthly averages of mantle
lengths of neon flying squid taken ranged from
22 to 32cm during August-October (Data of
Aomori Prefectural Fisheries Experimental Station) and from 35 to 42cm during June-November
(Data of Hokkaido Regional Fisheries Research
Laboratory), respectively.
The observed flights occurred both by day and
by night. Moreover, there seems to be no special
relationship between those flights and wind direction, wind force, or weather conditions. The
squid became airborne when dolphins existed in
the neighborhood (Nos. 3, 4, 5 and 7 in Table 1),
when the gillnet floatline sharply slapped against
the surface of the sea (Nos. 1 and 2 in Table 1), or
when a large squid jigging hook was cast into the
water (No. 8 in Table 1). Since the flights occurred habitually following a disturbance of the
sea surface, it seems that such the behavior may be
a form of fright reaction for escaping from danger.
Akimushkin2) as well as Clarke3) conjectured that
the squid made a flight when they were suddenly
frightened, or when they were trying to escape
from their enemies.
From the above, it is believed that neon flying
squid has a flying behavior to escape from their
frights and enemies such as dolphins, marlins and
so on. As Azuma5) has postulated, the flights
are considered to be gliding-type flights. The
initial leap and burst of speed is thought to be
supplied by the jet propulsion when a jet of water
is shot out of the funnel. However, the flight
behavior of neon flying squid seems to be limited
to the smaller individuals whose dorsal mantle
length is less than about 18cm, and whose body
weight is under about 170g. Larger individuals
are thought to be too heavy to fly. Furthermore,
this flying behavior suggests that the smaller ones
of neon flying squid lives mainly near the surface
of the sea by day and night.
Acknowledgements
I wish to thank Dr. T. Otsu in Honolulu, and
Dr. T. Sato, Hokkaido Regional Fisheries Research Laboratory, Kushiro, for reading the manuscript with suggestions for its improvement. Many
When the author interviewed the fishermen engaged in the neon flying squid fisheries , they had no available information on the flight of neon flying squid.
1174
Murata
thanks are also due to Mr. H. Yamawaki for
taking charge of a sighting survey in this cruise,
and the crew of the R/V Omi-Maru for their allout help in carrying out this survey.
References
1) G. F. Arata: Nautilus, 68, 1-3 (1954).
2) I. I. Akimushkin: Cephalopods of the sea of
the U.S. S.R. (translated by A. Mercado, edited
by R. Finesilver), Israel Program for Scientific
Translations, Jerusalem, 1965, 223 p.
3) M. R. Clarke: Review of the systematics and
ecology of oceanic squids, Adv. Mar. Biol., 4,
91-300 (1966).
4) T. Okutani: Report of 1976 annual meeting on
resources and fisheries of squid, Jap. Sea Reg.
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Japanese).
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