Experimental evidence for concentration-dependence and intraspecific variation of movement behaviour in American lobster (Homarus americanus) larvae

TitleExperimental evidence for concentration-dependence and intraspecific variation of movement behaviour in American lobster (Homarus americanus) larvae
Publication TypeJournal Article
Year of Publication2017
AuthorsPedersen, E. J., Stanley R. R. E., Snelgrove P. V. R., and Guichard F.
JournalCanadian Journal of Zoology
Volume95
Issue10
Number of Pages759-770
Date PublishedOct
Type of ArticleArticle
Reprint Number0008-4301
LTER Accession NumberWOS:000412886500007
Keywordsbenthic invertebrates; vertical-distribution; milne-edwards; coastal, dependence; larval dispersal, gulf; dispersal; transport; consequences; connectivity; populations;, Homarus americanus; American lobster; movement ecology; concentration, maine, Zoology
Abstract

Predicting dispersal paths of marine larvae with extended pelagic durations, such as American lobster (Homarus americanus H. Milne Edwards, 1837), requires understanding the cues to which larvae respond, and how that response reflects changes in larval behaviour. If larvae respond to conspecific presence by varying their movement, then this behaviour can bias laboratory estimates of environmental responses. We tested whether larvae actively decreased their local intraspecific density by measuring how the vertical distribution of larvae changed under high versus low concentrations of conspecifics. We observed weak increases in vertical dispersion at higher concentrations both in newly hatched larvae and in postlarvae, but not in intermediate larval stages. We also tested for differences in horizontal swimming behaviour in high and low concentrations, by fitting a novel random walk model that allowed us to model both larval interactions and persistent turning behaviours. We showed substantial reduction in diffusive behaviour under high concentration conditions resulting from more frequent turns by each larva, but no evidence for consistent avoidance of conspecifics. Our study is the first to demonstrate concentration-dependent behaviours in lobster larvae.

DOI10.1139/cjz-2016-0100
Print Copy LocationCan. J. Zool.