Benthic herbivores are not deterred by vrevetoxins produced by the red tide dinoflagellate Karenia brevis

Erik E. Sotka, Amanda McCarty, Emily A. Monroe, Nicole Oakman, Frances M. Van Dolah

Research output: Contribution to journalArticlepeer-review

13 Scopus citations

Abstract

Gulf of Mexico blooms of the dinoflagellate Karenia brevis produce neurotoxic cyclic polyethers called brevetoxins. During and after a red tide bloom in southwestern Florida, K. brevis cells lyse and release brevetoxins, which then sink to the benthos and coat the surfaces of seagrasses and their epiphytes. We tested the possibility that these brevetoxin-laden foods alter the feeding behavior and fitness of a common benthic herbivore within Floridean seagrass beds, the amphipod Ampithoe longimana. We demonstrated that coating foods with K. brevis extracts that contain brevetoxins at post-bloom concentrations (1 μg g-1 drymass) does not alter the feeding rates of Florida nor North Carolina populations of A. longimana, although a slight deterrent effect was found at eight and ten-fold greater concentrations. During a series of feeding choice assays, A. longimana tended not to be deterred by foods coated with K. brevis extracts nor with the purified brevetoxins PbTx-2 and PbTx-3. Florida juveniles isolated with either extract-coated or control foods for 10 days did not differ in survivorship nor growth. A similar lack of feeding response to brevetoxin-laden foods also was exhibited by two other generalist herbivores of the southeastern United States, the amphipod A. valida and the urchin Arbacia punctulata. Given that benthic mesograzers constitute a significant portion of the diet for the juvenile stage of many nearshore fishes, we hypothesize that the ability of some mesograzers to feed on and retain brevetoxins in their bodies indicates that mesograzers may represent an important route of vertical transmission of brevetoxins through higher trophic levels within Gulf of Mexico estuaries.

Original languageEnglish (US)
Pages (from-to)851-859
Number of pages9
JournalJournal of Chemical Ecology
Volume35
Issue number7
DOIs
StatePublished - 2009
Externally publishedYes

Keywords

  • Benthic food web
  • Epiphytic algae
  • Harmful algal bloom
  • Herbivory
  • Seagrass

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Biochemistry

Fingerprint

Dive into the research topics of 'Benthic herbivores are not deterred by vrevetoxins produced by the red tide dinoflagellate Karenia brevis'. Together they form a unique fingerprint.

Cite this