Effects of elevated ammonia levels on the fingernail clam, Musculium transversum, in outdoor experimental streams

• Published in: Archives of environmental contamination and toxicology Vol. 16; no. 2; pp. 225 - 231
• Main Authors: ZISCHKE, J. A, ARTHUR, J. W
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer-Verlag 01.03.1987; Berlin; New York, NY
• Subjects: ammonia; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on protozoa and invertebrates; Fresh water environment; Fundamental and applied biological sciences. Psychology; Musculium transversum; Freshwater environment; Ammonia; Reproduction; Bivalvia; Growth; Invertebrata; Mollusca; Survival
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/BF01055803

Caged fingernail clams were exposed to ammonia in experimental streams for 2-8 weeks during the summers of 1983 and 1984. Weekly mean unionized ammonia concentrations were 0.02-0.08, 0.04-0.25 and 0.14-0.56 mg per litre in 1983, and 0.04-0.20, 0.07-0.38 and 0.48-1.17 mg per litre in 1984. In 1983, clam survival was 50-85 per cent in control and low treatment streams , 30-55 per cent in the medium treatment stream, and zero in the high treatment stream. Older clams appeared more sensitive to ammonia than younger clams. Growth was adversely affected by medium ammonia concentrations. In the 1984 experiments, total yields of clams in control, low, medium and high ammonia streams, respectively, were 12.2, 4.7, 1.1 and 0.03 times the original stock. Reproduction, in terms of numbers of newborn clams recovered from the cages after 4 weeks' exposure, was 90 per cent lower in the low treatment stream than in the control stream. Based on the numbers of clams recovered from low and medium ammonia streams in 1984, the lowest mean concentration affecting survival was between 0.09 and 0.19 mg ammonia per litre. The unionized ammonia criterion suggested by the U.S. EPA (1985), and the British water quality criterion (1982), were 0.03-0.05 mg per litre (pH 8, temperature 20C) and 0.025 mg per litre, respectively.