Aspects of the Ecology of the Fishes of Holyrood Pond: A Coastal Lake with Occasional Access to the Sea Located in St. Mary's Bay, Newfoundland

• Published in: Internationale Revue der gesamten Hydrobiologie und Hydrographie
• Main Authors: O'Connell, Michael F., Andrews, Cater W., O'Brien, Johannah P., Dawe, Earl G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1984
• Subjects: Gadus morhua; Newfoundland
• Online Access: http://dx.doi.org/10.1002/iroh.19840690303; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Firoh.19840690303; https://onlinelibrary.wiley.com/doi/pdf/10.1002/iroh.19840690303

Abstract Physical and chemical conditions and fish were studied during spring and summer in 1974 and 1975 in Holyrood Pond, Avalon Peninsula, Newfoundland. It is a landlocked body of water lying at sea level (length = 21.72 km; maximum width = 1.55 km; maximum depth = 100.0 m) which is occasionally opened to the sea. The landlocked condition is caused by prevailing southwest winds and wave action which create a beach barrier that effectively isolates the mouth from St. Mary's Bay. Under landlocked conditions, there was a continual decrease in salinity and dissolved oxygen at all depths. Temperature profiles were of a dichothermic nature; a certain amount of temporal variability was noted in lower lying water. When the barrier was opened (by bulldozer) and the pond came under tidal influence, there was a replenishment of salt water and dissolved oxygen. Temperature profiles retained the same overall shape but were more erratic, and compared with the closed barrier condition, showed greater variability with time especially in the deeper water. A small amount of commercial fishing is carried out in the pond during both open and closed barrier conditions. A total of 30 species of fish was encountered during the sampling period. Of these, Salvelinus fontinalis, Gadus morhua, Urophycis tenuis, Pseudopleuronectes americanus and Alosa pseudoharengus were studied in detail. Aspects of their biology are compared with other populations and discussed in the context of environmental conditions peculiar to Holyrood Pond.