Effects of chronic ammonia exposure on gonad growth and survival in green sea urchin Strongylocentrotus droebachiensis

• Published in: Aquaculture Vol. 242; no. 1; pp. 313 - 320
• Main Authors: Siikavuopio, Sten I., Dale, Trine, Foss, Atle, Mortensen, Atle
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 20.12.2004; Elsevier Science; Elsevier Sequoia S.A
• Subjects: Ammonia; Animal aquaculture; animal growth; Animal productions; Aquaculture; Biological and medical sciences; Chronic ammonia exposure; Echinodermata; Echinoidea; environmental exposure; feed intake; Fundamental and applied biological sciences. Psychology; General aspects; Gonad growth; gonads; Green sea urchin; mariculture; Marine; mortality; Strongylocentrotus droebachiensis; Survival analysis; Toxicity; Chronic ammonia exposure; Gonad growth; Toxicity; Green sea urchin; Echinodermata; Growth; Survival; Ammonia; Chronic; Gonad; Strongylocentrotus droebachiensis; Echinoidea; Invertebrata; Sea urchin; Aquaculture
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2004.08.042

The effects of chronic unionised ammonia (UIA) exposure on mortality, gonad growth and feed intake (FC) in green sea urchin Strongylocentrotus droebachiensis were examined. Sea urchins with a mean (S.D.) initial weight of 58.2 (15.2) g were reared in shallow raceways (initial stocking density of 1.9 kg m −2) and exposed to four concentrations of UIA [0.0001 (control), 0.016 (low), 0.032 (medium) and 0.068 (high) mg l −1] for 42 days at 7.3 °C, salinity 33‰ and pH 8.04. Sea urchin mortality was influenced by UIA concentrations and increased with increasing levels of UIA. The mortality in the high-concentration group increased throughout the experimental period, and, ultimately, only 24% of the sea urchins survived. Compared to the control, gonad growth was significantly reduced at UIA concentrations above 0.016 mg l −1. Sea urchins from the exposed groups did not display a significant reduction in feed intake compared to the control, which suggests that the gonad growth reduction could not be attributed to a decreased feed intake. The present study demonstrates that adult green sea urchins show low tolerance to ambient unionised ammonia and are unable to maintain high gonad growth facing such conditions.