FISHERY BULLETIN: VOL. 78. NO. 3 



Table 2. — Shrinkage of laboratory-preserved northern anchovy, jack mackerel, and Pacific barracuda. Ratio is laboratory-preserved 

 size divided by previous live size (1.00 = no shrinkage). Standard length; head length; eye diameter; body depth at the pectoral, BD-1; 

 and body depth at the anus, BD-2. Measurements in millimeters. 



Standard length 



Head length 



Eye diameter 



BD-1 



BD-2 



Species Fixative No. Range Ratio SD No. Range Ratio SD Range Ratio SD Range Ratio SD Range Ratio SO 



Northern 

 anchovy 



Jack 



mackerel 

 Pacific 

 barracuda 



Formalin 61 3.9 -21.6 0.92 0.03 23 58-2.41 91 0.07 17-0.61 1.05 0.08 

 Alcohol 26 3.7 -19.0 1.00 04 — — — — — — — 



Bouins' 224 3.8 -15.7 92 .00 — — — — — — — 



_ _ 014-082 0.90 0.10 



Bouins 45 325-3.90 92 03 43 0.74-0.97 .82 



Bouins 54 3.75-5.23 .92 .02 56 1.00-1.63 .79 



.04 0.26-0,33 90 .06 0.48-0 67 0.75 05 20-0.26 .75 .05 

 .05 0.30-0.48 .82 .04 0.58-0.96 .75 .04 0.24-0,41 .77 .05 



'R Paloma. Fishery Biologist, National Marine Fisheries Service. La Jolla. Calif. Unpubl. data. 



the same preservative. Jack mackerel and Pacific 

 barracuda, deeper bodied than northern anchovy 

 at the same length, were preserved in Bouin's fixa- 

 tive, and northern anchovy were preserved in 

 Formalin. Head length, eye diameter, and body 

 depth shrank more in jack mackerel and Pacific 

 barracuda larvae than in northern anchovy larvae 

 (Table 2). Eye diameter of northern anchovy in- 

 creased in size after Formalin preservation; the 

 increase was significant (P = 0.058; paired ^-test) 

 but small (0.0145±0.0031 mm). 



Alcohol preservation did not cause a change in 

 northern anchovy standard length (Figure 4, 

 Table 2); smaller body parts were not mea- 

 sured because alcohol distorted the larvae and 

 they were extremely difficult to remeasure after 

 preservation. 



6 8 10 12 14 16 18 



LIVE STANOaRD LENGTH Imm) 



Figure 4. — Ratio of subsequent laboratory-preserved standard 

 length to live standard length in northern anchovy preserved in 

 alcohol . Dots are means of 10 larvae. Circles represent individual 



fish. 



Net-Treatment Shrinkage 



Shrinkage of net-treated larval northern an- 

 chovy varied with handling time and fish size (Ta- 



TABLE 3. — Shrinkage in standard length (millimeter) of northern anchovy larvae after net handling for four time intervals (X2). Ratio 

 (R) = mean net standard length (X,) divided by mean live standard length (L). Ratio of 1.00 = no shrinkage. 



'Estimated ratio = In X, -in L; Equation (4), see text and Table 4. 



688 



