Jwel Project No. 1203 Marine Mammals and Seabirds In
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JWEL PROJECT NO. 1203 MARINE MAMMALS AND SEABIRDS IN THE STRAIT OF BELLE ISLE LHP 98-12 PREPARED FOR NEWFOUNDLAND AND LABRADOR HYDRO LABRADOR HYDRO PROJECT 500 COLUMBUS DRIVE P. O. BOX 12400 ST. JOHN’S, NEWFOUNDLAND A1A 2X8 PREPARED BY JACQUES WHITFORD ENVIRONMENT LIMITED 607 TORBAY ROAD ST. JOHN’S, NEWFOUNDLAND A1A 4Y6 Tel: (709) 576-1458 Fax: (709) 576-2126 and MICHAEL KINGSLEY November 8, 2000 With Updated Executive Summary and Introduction by Nalcor Energy – November 2009 EXECUTIVE SUMMARY Updated by Nalcor Energy – November 2009 The proposed Labrador-Island Transmission Link includes the installation of a submarine cable across the Strait of Belle Isle. Construction activity in and adjacent to the marine environment associated with cable installation has the potential to interact with marine mammals and seabirds in the project area. The primary objective of the 1998 marine mammal and seabird survey in the Strait of Belle Isle was to estimate the relative abundance of marine mammals and seabirds in the Strait and surrounding area during the ice-free season. These baseline data will contribute to the requirements for a future environmental assessment and any follow-up monitoring, if required. Aerial and boat-based surveys were conducted approximately every three weeks from July to December, 1998. The aerial survey covered the entire Strait of Belle Isle and the northeast Gulf of St. Lawrence, an area of approximately 5,400 km 2. The boat-based survey covered an area of approximately 725 km 2 in the general area of the proposed cable crossing corridors. Nine species of whales and dolphins and two species of seals were sighted during the 1998 marine mammal survey of the Strait of Belle Isle. Marine mammals in the Strait of Belle Isle were most abundant in August, with harbour porpoise, white-sided dolphin, and humpback, fin and the minke whales at their peak relative abundance. The relative abundance of most species, except the white-sided and white-beaked dolphins, declined after August. The most common baleen whale, the humpback, appears to be most frequent near Belle Isle and along transects running southeast to the Northern Peninsula from L’Anse au Loup to L’Anse au Clair. The harbour porpoise, the most abundant species during the survey, was most frequent near the western end of the study area, along the transects running northwest to Labrador from Castor’s River to Eddie’s Cove West and along transects running southeast to the Northern Peninsula from L’Anse au Clair to Blanc Sablon. Overall, there appeared to be a preference for the Labrador side of the Strait by most marine mammals. A dedicated observer conducted seabird surveys during four of the boat-based mammal surveys between August and October. A total of 29 seabird species were seen during the surveys between August and October. When considering all surveys together, there were just 10 species that comprise the five most abundant species during each survey. The total number of species seen for each of the surveys was consistent. However, species composition and abundance varied greatly between surveys. Species that breed in the area in relatively large numbers (Greater Black- backed Gulls, Herring Gulls, Atlantic Puffin, and Common Murre) were most abundant in the August survey. The results of the 1998 marine mammal and seabird survey and literature review reported herein will be used in the Project’s Environmental Impact Statement (EIS), along with any additional information and literature that has become available since that time, in order to describe the existing (baseline) conditions in the Strait of Belle Isle area which could potentially interact with Project works and activities. JWEL Project No. 1203 • Marine Mammals & Seabirds • November 8, 2000 • Updated Sections - November 2009 Page i TABLE OF CONTENTS Page No. 1.0 INTRODUCTION ........................................................................................................................................... 1 1.1 Project Overview.....................................................................................................................................1 1.2 Marine Mammal and Seabird Survey: Study Purpose and Rationale .....................................................3 2.0 DESCRIPTION OF STUDY TEAM .................................................................................................................... 5 3.0 SUMMARY OF STUDY OBJECTIVES ............................................................................................................... 8 3.1 Marine Mammals Surveys ......................................................................................................................8 3.2 Seabird Surveys.......................................................................................................................................8 4.0 DESCRIPTION OF THE STUDY AREA .............................................................................................................. 8 4.1 Study Area...............................................................................................................................................8 4.2 Coastal Geomorphology..........................................................................................................................8 4.3 Oceanography.........................................................................................................................................9 4.4 Meteorology............................................................................................................................................9 4.5 Ice Conditions..........................................................................................................................................9 5.0 METHODS .................................................................................................................................................. 10 5.1 Aerial Survey .........................................................................................................................................10 5.1.1 Aerial Survey Design....................................................................................................................10 5.1.2 Aerial Survey Execution...............................................................................................................12 5.2 Boat-Based Survey ................................................................................................................................12 5.2.1 Marine Mammals........................................................................................................................12 5.2.2 Seabirds.......................................................................................................................................13 5.3 Mammal Survey Data Analysis..............................................................................................................13 5.3.1 Line-Transect Analysis of Boat Survey Sightings .........................................................................17 5.3.2 Line-Transect Analysis of Aerial Survey Sightings .......................................................................18 5.3.3 Comparison of Boat Survey with Aerial Survey Sighting Rates ...................................................20 5.4 Quality Assurance/Quality Control .......................................................................................................20 6.0 RESULTS..................................................................................................................................................... 21 6.1 Literature Review of Historical Marine Mammal Data .........................................................................21 6.1.1 Whales.........................................................................................................................................21 6.1.2 Seals ............................................................................................................................................39 6.2 Effects of Construction on Marine Mammals.......................................................................................41 6.3 Survey Results.......................................................................................................................................43 6.3.1 Marine Mammals........................................................................................................................43 6.3.2 Seabirds.......................................................................................................................................56 7.0 DISCUSSION AND CONCLUSION ................................................................................................................. 65 7.1 Marine Mammals..................................................................................................................................65 7.1.1 Blue Whale ..................................................................................................................................65 7.1.2 Minke Whale ...............................................................................................................................65 7.1.3 Fin Whale ....................................................................................................................................66 7.1.4 Long-Finned Pilot (Pothead) Whale ............................................................................................66