Toxicity thresholds for juvenile freshwater mussels Echyridella menziesii and crayfish Paranephrops planifrons, after acute or chronic exposure to Microcystis sp
Article first published online: 4 APR 2012
Copyright © 2012 Wiley Periodicals, Inc.
Volume 29, Issue 5, pages 487–502, May 2014
How to Cite
Clearwater, S. J., Wood, S.A., Phillips, N.R., Parkyn, S.M., Van Ginkel, R. and Thompson, K.J. (2014), Toxicity thresholds for juvenile freshwater mussels Echyridella menziesii and crayfish Paranephrops planifrons, after acute or chronic exposure to Microcystis sp. Environ. Toxicol., 29: 487–502. doi: 10.1002/tox.21774
- Issue published online: 7 APR 2014
- Article first published online: 4 APR 2012
- Manuscript Accepted: 7 FEB 2012
- Manuscript Revised: 5 FEB 2012
- Manuscript Received: 28 OCT 2011
- New Zealand Foundation for Research, Science and Technology. Grant Number: CO1X0803
- freshwater mussels;
- freshwater crayfish;
- Te Arawa;
- Rotorua Lakes;
- Microcystis sp.
Survival of juvenile freshwater mussels (Echyridella menziesii (Gray, 1843) formerly known as Hyridella menziesi) and crayfish (Paranephrops planifrons, White, 1842) decreased after four days exposure to microcystin-containing cell-free extracts (MCFE) of Microcystis sp. at concentrations typical of severe cyanobacterial blooms. Crayfish survival was 100, 80, and 50% in microcystin concentrations of 1339, 2426, and 11146 μg L−1 respectively, and shade- and shelter-seeking behavior was negatively affected when concentrations were ≥2426 μg L−1. Mussel survival decreased to 92% and reburial rates decreased to 16% after exposure for 96 h to MCFE containing microcystins at concentrations of 5300 μg L−1. Crayfish survival was 100% when fed freeze-dried Microcystis sp. incorporated into an artificial diet (6–100 μg microcystin kg−1 ww) at dietary doses from 0.03 to 0.55 μg g−1 body weight d−1 for 27 days. Specific growth rate was significantly lower in crayfish fed ≥0.15 μg g−1 body weight day−1 compared with controls, but not compared with a diet incorporating nontoxic cyanobacteria. Microcystins accumulated preferentially in crayfish hepatopancreas and mussel digesta as MCFE or dietary concentrations increased. These laboratory data indicate that, assuming dissolved oxygen concentrations remain adequate, and no simultaneous exposure to live Microcystis sp. cells, cell-free microcystins will only be a significant stressor to juvenile crayfish and mussels in severe Microcystis sp. blooms. In contrast, crayfish were negatively affected by relatively low concentrations of microcystins in artificial diets compared with those measured locally in benthic cyanobacterial mats. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 487–502, 2014.