Article
Variation in vertical distribution of sand dollar larvae relative to haloclines, food, and fish cues
Journal of Experimental Marine Biology and Ecology
(2012)
Abstract
Larvae of marine invertebrates may vertically position themselves in locations where conditions favor growth, development, and survival. Areas in stratified water columns with favorable salinities, concentrated food, or low predation may increase the probability for larvae to reach settlement. We examined the vertical distribution of three developmental stages of the echinoid Dendraster excentricus in response to haloclines, food cues, and predator cues in laboratory microcosms. Embryos, 4-arm plutei, and 8-arm plutei responded similarly to haloclines by swimming upward through haloclineswhen the bottom layer was at salinity 31 (ambient) and the top layer was at 27 or 23. The centers of larval mass for all stages were near the halocline when the top layer was at salinity 19 or 15. We tested the tolerance of each stage to prolonged exposure to each of these salinities and found sublethal effects under salinity 23, suggesting costs for concentrating in low salinity environments. To test the response of 4-arm larvae to food patches, we constructed a food layer composed of cells or supernatant of one of three species of algae (Dunaliella tertiolecta, Isocrysis galbana, Rhodomonas sp.). The larvae distributed above the food layer in the presence of two algal species, D. tertiolecta and Rhodomonas sp., but distributions were similar to controls when I. galbana was tested. Finally, larvae significantly changed their distributions in response to cues from a potential predator (juvenile perch), showing an avoidance behavior. The observed larval behaviors in response to haloclines, algae, and a potential predator suggest that D. excentricus plutei behaviorally respond to their environment and likely change position in response to environmental cues in the field.
Keywords
- Behavior,
- Dendraster excentricus,
- Embryos,
- Pluteus,
- Pycnocline,
- Salinity
Disciplines
Publication Date
March 15, 2012
DOI
https://doi.org/10.1016/j.jembe.2012.01.008
Publisher Statement
Copyright © 2012 Elsevier B.V. All rights reserved.
Citation Information
Shawn M. Arellano, Adam M. Reitzel and Cynthia A. Button. "Variation in vertical distribution of sand dollar larvae relative to haloclines, food, and fish cues" Journal of Experimental Marine Biology and Ecology Vol. 414-415 (2012) p. 28 - 37 Available at: http://works.bepress.com/shawn-arellano/6/