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Effects of simulated blasting on mortality of Rainbow Trout eggs
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- Author(s) / Creator(s)
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Blasting in or near water can negatively affect fish. In Canada, there are maximum allowable limits for blasting-induced overpressure (100 kPa) and peak particle velocity (PPV; 13 mm/s) to protect fish and their incubating eggs, respectively. No studies, however, have related PPVs from blasting to egg mortality. To address this information gap, we developed a laboratory blast simulation procedure for relating egg mortality to different levels of PPV exposure. Eggs of rainbow trout Oncorhynchus mykiss were subjected to PPVs of up to 245.4 mm/s during six sensitive developmental stages. Eggs also were exposed to a previously described drop height method, in which the final velocity of the eggs is used to estimate PPV exposure; we tested both the original out-of-water treatment and an in-water drop height treatment. Using blast simulation, egg mortality increased at only one developmental stage and only from exposures greater than 132.3 mm/s. Mortality was greater when eggs were placed in spawning gravel versus free in containers, although mortality generally increased at the same PPV level for both treatments. In the drop height method, eggs held out of water were more sensitive to a given exposure level than were eggs held in water. The drop height method may not provide an accurate assessment of blasting-induced PPVs, especially when eggs are out of water, but should be suitable for comparing the egg sensitivity of different species or development stages. Our controlled, laboratory-based results indicate that the Canadian PPV guidelines provide ample protection for rainbow trout eggs within spawning beds.
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- Date created
- 2008
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- Subjects / Keywords
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- Type of Item
- Article (Published)
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- License
- ©Copyright by the American Fisheries Society 2008