Temporal changes in release rates and quality of lobster (Homarus americanus) feeding attractants from herring (Clupea hareng us) baits

Abstract

Primary amine release rates of various herring preparations (frozen, fresh, and 20% salt) were determined over a 45h period in order to evaluate characteristic chemical‐release profiles of baits for lobsters (Homarus americanus). Over the first 5.5h, salted herring had high but declining amine release rates. A similar, less pronounced pattern of amine release was observed for frozen herring while that of fresh herring remained stable and low. After 12h, the release rates of all preparations were equivalent and low. A behavioral bioassay of post‐larval lobsters was used to determine the level of directed food‐search response to frozen and salted herring leachates collected over the 45h period and adjusted to equimolar amine concentrations. No differences in attractiveness among the two bait types were observed at any one time of leaching. Attractants were confined to polar, primary amine containing fractions. There was, however, a decrease in response to the leachates with time suggesting that decay adversely affected attractant solution milieu. Removal of compounds of low and intermediate polarity did not remove inhibition effect. The addition to attractant solutions of four amines associated with fish spoilage (trimethylamine, cadaverine, putrescine, histamine) did not result in response inhibition or enhancement.

Key words:

• Bait
• lobster
• herring
• feeding attractants

Notes

Present address: Department of Biology, Georgia State University, Atlanta, GA 30302, USA.