134 
Fishery Bulletin 120(2) 
e Observed catch 
— Predicted catch 
Ww 
— 
© 
Sg 
i?) 
Q 
Ke) 
{%2) 
ro) 
=) 
S 
‘= 
oO 
iO 
© 
Oo 
Frequency 
Deviance residuals 
[urieripe iui 
4 0 4 8 0 50 100 150 
Deviance residuals Month 
Figure 6 
Predicted catch (000s) 
0 10 20 30 
Observed catch (000s) 
Fit of the stock assessment model to observed data on catch of flathead lobsters (Thenus 
orientalis) by small fishing boats, called tarad, from 1995 through 2008 in the waters of 
Saudi Arabia in the Arabian Gulf (top panel). Diagnostic plots for the model are also pro- 
vided (bottom panels). 
EA 
on 
a 
Yee 
ts 
SI 
—— 
Te se 
Ti 
nee 
root 
eres 
“ 
SS 
. 
ES 
PSY | | 
1995 1997 1999 2001 2003 2005 2007 
Year 
Figure 7 
Predicted biomass (solid line) of flathead lobster (Thenus orientalis) 
caught in the waters of Saudi Arabia in the Arabian Gulf during 
1995-2008. The gray polygon indicates the 0.5 standard error. The 
rectangles formed with dashed lines indicate the fishing season for 
the flathead lobster. 
for development of a new fishery is the very 
wide fluctuations in abundance, driven by fluc- 
tuations of 2 orders of magnitude in recruit- 
ment and by intense M. In 8 months of the time 
series, stock biomass was below 500 t or 2.7 
million flathead lobsters, and in the months of 
higher abundance the stock could have over 
10,000 t or 55 million flathead lobsters. Because 
of the wide fluctuations in stock size, it would 
be necessary to adopt a precautionary stance 
regarding the potential to resume landings 
either as allowed bycatch of shrimp trawlers 
or as a targeted stock in a specialized small- 
scale fishery. Nevertheless, it should also be 
noted that the highest landings recorded as 
bycatch of the shrimp trawlers (~50 t in 2005) 
amount to just 10% of the minimum monthly 
biomass. Therefore, it should be safe to resume 
allowed landings of flathead lobsters as a com- 
mercially valuable bycatch of shrimp trawling, 
but the development of a targeted small-scale 
fishery would require careful fine-tuning of 
gear efficiency, magnitude of effort, and sea- 
sonal closures, considering that the very low 
biomass of the stock may drop during natural 
fluctuations. 
