Page 6 - Ragonese_Bianchini_1996

130 S. Ra;;onese. M.L. Bianchini l Fisheries Research 26 ( 1996) 125-137

90
•

80
e
e
.:.l
..
~ 70
-=
c
~
.:i 60
~
"" e
...
-<:
50

40
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Brody's codficient (Kiy)

Fig. 3. Scatterplot of asyrnptotic length and Brody's coefficient resulting frorn bootstrapping the LFD under the
ELEFAN-1 routinc with the corresponding bi variate confidence ellipsoid ( 95%), for Aristeus antennatus. The
asterisk denote., the location of the estirnates derived by MIX.

t han 5 kg h - 1 ( Ragoncse and Bianchini, 1992). with the catch dominated by females (se x
ratio 6: l). lncidentally, the captures of Aristeus antennatus are not correlated with the
abundance or scarcity of Aristaeomorphafoliacea.
A total or 79R females were measured, i.e. 156, 129, 280 and 233 for the spring, surnmer,
auturnn and winter survey, respectively. The smallest length is 22 rnm CL, and the largest
66 m m CL. The me an length of the pooled sample is 41.3 m m CL ( with an SD of 8.7 m m);
most of thc sample ( 98%). falls in the range 26-61 m m CL. M ales are smaller, averaging
only 29.7 mm CL.
Lcngth frequency distributions (Fig. 2) show a t !cast two clear modes. The start of
recruitrnent is obscrved in summer, but the young-of-the-year appcar to be fully recruited
only in autumn when the cohort is well represented and discriminated from the adult stock.

Table l
Dcscriptive statistics for asymptotic length (CL.; mrn). Brody's coefficicnt ( Kly ). and index of goodness of fit
( !?, ) d cri v ed after bootstrapping (n= 99) the LFD under the ELEFAN-I routine. for Aristeus antennatus
Statistics Fast Slow Cornbined

Cl.. Klr R, CL KA R, CL. Klv R,
Minirnum 55.0 0.67 0.43 61.0 0.38 0.35 55.0 0.38 0.35
Maxirnurn 67.0 0.79 0.78 87.0 0.5 l 0.84 87.0 0.79 0.84
Me an 61.0 0.74 0.57 74.5 0.45 0.54 67.7 0.59 0.56
SE 0.1 0.01 0.01 0.3 0.01 0.01 0.5 0.01 0.01
Skcwness 02 - () 81 0.00 0.6 -026 0.01 0.2 -0.01 0.00
Mcdi an 61 () o 74 0.57 74.0 0.45 0.54 67.0 0.53 0.55