Consultant's Report - Minnesota State Legislature

Figure 2 demonstrates that hatching and survival rates from 0 - 24 h were low (7
%). Survival from 24 96 h was much higher, particularly between 72 - 96 h, when
survival was 97 %. The biological half-life for 72- to 96-h-old larvae was 102.2 h, which
was close to the range of 36.0 - 67.2 presented by Fisher et at. (1994) for laboratoryspawned
D. potymorpha of the same age. Mortality beyond 100 h is observed due to
larvae no longer feeding on yolk sacs and subsequently requiring micro-algae food.
Background control mortality was accounted for in the subsequent toxicity tests by using
Abbott's con-ection within the ToxCalc© software package (Tidepool Scientific,
McKinleyville, CA).
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