Publication Abstract

Length changes in herring (Clupea harengus) larvae: effects of capture and storage in formaldehyde and alcohol

C.J. Fox

The effects on standard length of storing laboratory-reared larval herring (9-19 mm livt length) in 4°% buffered formaldehyde or 70°o buffered ethanol with and without simulated capture b, towed net were assessed. Lengths during storage were considered stable after 15 days for larvae place( directly in formaldehyde. and after 30 days for larvae placed directly into alcohol or for larvae treatec by net-capture simulation before storage. The following linear regressions described the relationship: between live length and the stored lengths of larvae after these times: for larvae stored directly it formaldehyde, L = 1.765 + 0.867 x X,: for larvae stored directly in alcohol. L = 0.564 + 0.971 x X,: fo larvae subjected to net-capture simulation then stored in formaldehyde, L = 0.98-1 + 0.993 x X,; and fo larvae subjected to net-capture simulation then stored in alcohol, L = 0.532 + 0.989 x X„ where L = livt standard length and X, = standard length after storage. The non-linear regression formula parameter ized by Theilacker (Fish. Bull. US, 78.685-692.1980) for northern anchovy larvae provided a good fit t< the data for herring larvae subjected to net-capture simulation and then stored in formaldehyde. How ever. the model had to be re-parameterized to provide a good fit for larvae stored in alcohol. Tht precision achieved in length measurements using a computer-aided measuring system is also discussed.

Reference:

C.J. Fox, 1996. Length changes in herring (Clupea harengus) larvae: effects of capture and storage in formaldehyde and alcohol. Journal of Plankton Research, 18: 483-493.