Estimating live standard length of net-caught walleye pollock larvae using measurements in addition to standard length

In our study, we used measurements of other body parts as ancillary data to estimate live lengths of preserved fish larvae caught at sea. We report on two common preservatives: ethanol and formalin. To avoid the problem of duration of time in the net, shrinkage correction equations were formulated by pooling data of known-length larvae that were treated for varying durations in simulated plankton tows in the laboratory and then preserved. Morphometric measurements were collected on preserved larvae that could be used in equations to obtain more accurate and precise estimates of live length. Rather than use alternative body part measurements as a substitute for length, we hypothesized that other body parts, nonshrinking or otherwise, could be used to correct for shrinkage, in spite of how long larvae had been in nets.