Diversity of marine benthic communities from nearshore environments on the Labrador and Newfoundland coasts

• Main Author: Barrie, John Dickie
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 1979
• Subjects: Newfoundland
• Online Access: https://research.library.mun.ca/7764/; https://research.library.mun.ca/7764/1/Barrie_JohnDickie.pdf; https://research.library.mun.ca/7764/3/Barrie_JohnDickie.pdf

The structure and species diversity of benthic communities were examined from samples collected by SCUBA and Shipek grab from sand bottoms on the Labrador coast and in Conception Bay Newfoundland. The effects of the physical environment on the benthic community were studied using the factors of depth, distance offshore, substrate type, substrate diversity and exposure to open water. -- Two communities were found in the areas surveyed; one on finer sands in protected environments characterized by Prionospio steenstrupi and Pectinaria granulata and one on coarser sands in more exposed environments characterized by Diastylis sp. and Nephtys longosetosa. Three species found in Labrador, Laonome kröyeri, Amphiophiura convexa and Onisimus affinis were new records for the Labrador coast. -- Species diversity was found to be greatest at medium exposures, where heterogeneity of the environment was greatest and on substrates with the greatest diversity of grain sizes. Variations in numbers of species between Newfoundland and Labrador and between sites with similar physical conditions was found to be due to non-burrowing species. Attempts were made to explain differences in number of species for sites on the Labrador coast and between Newfoundland and Labrador sites as the basis of differences in exposure, substrate conditions and predation.