Copper Toxicity to Sperm, Embryos and Larvae of Topsmelt 'Atherinops affinis', with Notes on Induced Spawning

摘要

Topsmelt, Atherinops affinis, were induced to spawn repeatedly in the laboratory using a combination of environmental cues. Temperature spikes appeared to be the most important factor to induce spawning. Egg production peaked four days after a 2C increase in water temperature, and declined thereafter. A series of static toxicity tests compared the relative sensitivity of topsmelt sperm, embryos, and larvae to copper chloride. Of the three developmental stages compared, sperm were more sensitive than embryos, and embryos were more sensitive than larvae. The mean EC50 from four separate 48-h fertilization experiments was 109 micrograms copper/liter. The mean EC50 from three, 12-day embryo development development tests was 142-147 micrograms copper/liter, depending on the endpoint used. The mean LC50 from three, 96-h larval mortality tests was 238 micrograms copper/liter. Topsmelt are amenable to laboratory culture and are a promising eastern Pacific toxicity test species. (Copyright (c) 1991 Elsevier Science Publishers Ltd, England.)