During harmful algal blooms (HABs), fish at sensitive developmental stages (embryo and larva) are exposed to toxins released from algal cells into the surrounding water column. Although it is well known that the dietary uptake of toxic algae can cause acute fish kills in adult fish, little is known about the sublethal, chronic effects of dissolved toxin exposure on early life history stages of marine fish. Exposure during these sensitive developmental stages may impact metabolism, growth, viability, fecundity and/or recruitment of marine species. Important fish populations that are at risk include northern anchovies (Engraulis mordax) and Pacific herring (Clupea pallasi), species that are vital to marine food webs and commercial fisheries.

The goal of the present study is to define the specific sublethal effects of dissolved algal toxin exposure on early development in economically and ecologically important marine fish species. Because of the inherent difficulties of working with marine planktivorous fish larvae, we are first using the zebrafish (Danio rerio), as an experimental model system to define the chronic developmental effects of algal toxin exposure on early life history stages of fish. Our aim is to identify sublethal indicators of developmental toxicity that can be clearly related to the health or performance of fish at later life history stages. After toxicological endpoints that are specific for each toxin have been identified in the model, we will use these markers to establish sublethal toxicological thresholds in marine species of concern.

Investigators
Kathi Lefebvre and Nat Scholz

Collaborators
Vera Trainer, Marine Biotoxins Program, NWFSC, NOAA Fisheries

Paul Herschberger and Nancy Elder, Marrowstone Marine Laboratory, USGS

Support
Ecology and Oceanography of Harmful Algal Blooms (ECOHAB)

Relevant Publications/Presentations
Lefebvre, K.A., Trainer, V.L. and Scholz N.L. (2004) Morphological abnormalities and sensorimotor deficits in larval fish exposed to dissolved saxitoxin. Aquatic Toxicology 66:159-170.

Lefebvre, K.A. (2003) Morphological abnormalities and sensorimotor deficits in larval fish exposed to dissolved saxitoxin. Second Symposium on Harmful Algae in the U.S., Woods Hole, MA. Poster presentation.

Lefebvre, K.A. (2003) Temporal patterns of mechanosensory impairment caused by algal toxin exposure in larval zebrafish. Symposia on Developing Zebrafish Models for Neurobehavioral Toxicology, Behavioral Toxicology Society & Neurobehavioral Teratology Society Joint Meeting, Philadelphia, PA. Invited speaker.

Lefebvre, K.A., Trainer, V.L. and Scholz, N. (2003) Effect of a common algal toxin on early development and behavioral performance in fish. Proceedings of the Georgia Basin/Puget Sound Research Conference 2003, Vancouver, British Columbia. Oral presentation.

Lefebvre, K.A., Scholz, N., Baugh, K. and Trainer, V.L. (2002) Sublethal effects of saxitoxin on early development and behavioral performance in fish. Xth International Conference on Harmful Algae, St. Pete Beach, FL. Oral presentation.

Lefebvre, K.A., Bargu, S., Kieckhefer, T. and Silver M.W. (2002) From sanddabs to blue whales: the pervasiveness of domoic acid. Toxicon 40:971-977.

Lefebvre, K.A., Silver, M.W., Coale, S.L. and Tjeerdema T.S. (2002) Domoic acid in planktivorous fish in relation to toxic Pseudo-nitzschia cell densities. Marine Biology 140:625-631.

Lefebvre, K.A., Dovel, S.L. and Silver M.W. (2001) Tissue distribution and neurotoxic effects of domoic acid in a prominent vector species, the northern anchovy. Marine Biology 138:693-700.