202 
NOAA 
National Marine 
Fisheries Service 
Abstract— With data from Taiwan- 
ese jiggers that targeted the Ar- 
gentine shortfin squid (Illex argen- 
tinus) in the southwest Atlantic 
between 1986 and 2010, we used 
log-transformed catch per unit of ef- 
fort (logLD as an index of the abun- 
dance of this squid to explore squid 
recruitment strength in response to 
environmental conditions. The log{7 
was negatively correlated with sub- 
surface seawater temperature (at a 
depth of 5 m) observed during Feb- 
ruary and April on the southern 
Patagonian shelf during the fishing 
season. The logf/ was also correlated 
with the Antarctic Oscillation (AAO), 
positively correlated in December 
of the fishing season and in March 
and May of the previous 2 years, 
and negatively correlated in Novem- 
ber and December of the previous 
2 years. A generalized linear model 
selected 4 environmental variables 
as predictors of annual catches that 
accounted for 83% catch variation: 
AAOs in November and March of 
the previous 2 years and subsurface 
seawater temperatures in March 
of the current and previous year 
in the southern location. The AAO 
would not directly affect the squid 
abundance more than 1 year later 
and biotic and abiotic linkages be- 
tween atmospheric circulation pat- 
terns and stock fluctuations are not 
understood. 
Manuscript submitted 17 February 2014. 
Manuscript accepted 25 February 2015. 
Fish. Bull. 113:202-212 (2015). 
doi: 10.7755/FB.113.2.8 
The views and opinions expressed or 
implied in this article are those of the 
author (or authors) and do not necessarily 
reflect the position of the National 
Marine Fisheries Service, NOAA. 
Fishery Bulletin 
fy- established 1881 
Spencer F. Baird 
First U.S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
The Antarctic Oscillation index as an 
environmental parameter for predicting 
catches of the Argentine shortfin squid Ullex 
argentinus . ) (Cephalopoda: Ommastrephidae) 
in southwest Atlantic waters 
Ke-Yang Chang 1 2 
Chih-Shin Chen 3 
Hui-Yu Wang 4 
Chin-Lau Kuo 2 
Tai-Sheng Chiu (contact author ) 1 
Email address for contact author: tschiu@ntu.edu.tw 
1 Department of Life Science 
National Taiwan University 
Taipei 106, Taiwan 
2 Fisheries Research Institute 
199 Hou-lh Road 
Keelung 202, Taiwan 
3 Institute of Marine Affairs and 
Resource Management 
National Taiwan Ocean University 
Keelung 202, Taiwan 
4 Institute of Oceanography 
National Taiwan University 
Taipei 106, Taiwan 
The Argentine shortfin squid ( Illex 
argentinus) occurs on the Patagonian 
shelf and slope (22-55°S) in the south- 
west Atlantic (Jereb and Roper, 2010). 
Commercial harvesting of this squid 
species extends almost throughout 
its distributional range, particularly 
along the shelf break (Beddington et 
al., 1990; Haimovici et al. 1998; Lap- 
tikhovsky et al. 1 ). Concentrations of 
Argentine shortfin squid are found 
between 45° and 46°S in January and 
February, and then gradually migrate 
southward toward the Falkland Is- 
lands, where they grow rapidly (Bas- 
son et ah, 1996; Haimovici et ah, 1998). 
The catch is high between March and 
May in the Falkland Interim Conser- 
1 Laptikhovsky, V. V., A. V. Remeslo, 
C. M. Nigmatullin, and I. A. Polish- 
chuk. 2001. Recruitment strength 
forecasting of the shortfin squid Illex 
argentinus (Cephalopoda: Ommastrephi- 
dae) using satellite SST data, and some 
consideration of the species’ popula- 
tion structure. ICES Council Meeting 
(C.M.) Documents 2001/K:15, 9 p. 
vation Zone (Beddington et ah, 1990; 
Basson et ah, 1996). Toward the end of 
the fishing season, Argentine shorfin 
squid begin migrating northward to 
spawn and die around July or August 
(Arkhipkin, 1993; Basson et ah, 1996). 
The fishery for Argentine short- 
fin squid is one of the most impor- 
tant squid fisheries in the world. The 
greatest tonnage has been taken, in 
descending order, by Korea, Japan, 
Taiwan, Poland, Spain, China, Bra- 
zil, Falkland Islands, Cambodia, and 
Honduras (Jereb and Roper, 2010). 
Taiwan entered the Argentine short- 
fin squid fishery by jigging in 1983, 
and approximately 120 vessels have 
fished in this area annually and have 
accounted for approximately 30% of 
the total catch of this squid (Chen et 
ah, 2007a). The fishing sites of the 
Taiwanese jiggers in past decades 
have included nearly the entire dis- 
tributional range of this species, and 
the main fishing season usually runs 
from January through June (Chen et 
ah, 2007a, 2007b). 
