Abstract
The Fundy Ocean Research Center for Energy (FORCE) developed and operates a tidal energy demonstration site and support facility along the north shore of Minas Passage in Nova Scotia’s Bay of Fundy. As a condition of its regulatory approvals to operate at the site, FORCE has been required to carry out an environmental effects monitoring program (EEMP) to provide information on the marine ecosystem, including seabirds and marine mammals, before and after installation of tidal energy devices, to verify predictions that these organisms are not likely to be impacted by tidal energy development activities. FORCE conducted vessel‐ and shore‐based observational surveys for seabirds and marine mammals beginning in 2009 and extending until 2012 as part of ongoing Environmental Effects Monitoring Program (EEMP) activities at the site.
The latest phase of the EEMP extends from 2016‐2021 and includes year‐round shore‐based monitoring of marine seabirds. The first year of shore‐based surveys under the present EEMP covers the period from May 6, 2016 to May 1, 2017, conducted from the FORCE Visitor Center on the north shore of Minas Passage, near Parrsboro, Nova Scotia, and covering a period both before and during the operation of a grid‐connected tidal turbine which was installed in early November, 2016, and which operated through the end of the survey period.
Surveys targeted the occurrence, abundance, local distribution, and annual pattern of composition and abundance of seabirds and water‐associated birds (loons, cormorants, waterfowl, gulls, alcids), in coastal waters of Minas Passage, which included the zone designated for deployment of tidal energy devices (the ‘Crown Lease’ area) and adjacent waters both inshore and offshore and on Black Rock, an island at the site. Thirty‐two (32) species of water‐associated birds and shorebirds, and three marine mammal species (Harbour Porpoise, Harbour Seal and Harp Seal) seen incidentally at the site, were observed during the year. The most common and abundant bird species included gulls (Great Black‐ backed Gull and Herring Gull, present in 88 and 100% of surveys respectively), Common and Red‐ throated Loon, Common Eider, Black Guillemot, Black Scoter, Double‐crested Cormorant and Great Cormorant. Least common species included shorebirds (Lesser Yellowlegs, Purple Sandpiper and Spotted Sandpiper), as well as Northern Gannet, Red‐necked Grebe, Razorbill, Common Murre, Blue‐winged Teal, Arctic Loon and Snow Goose, which were each observed on single surveys. An estimated four pairs of Black Guillemot and several Great Black‐backed Gull were nesting on Black Rock, but there was no indication of nesting by Herring Gull, Double‐crested Cormorant, or Great Cormorant on the island during the year.
Abundance of water‐associated birds (loons, cormorants, waterfowl, gulls, alcids) at the Minas Passage site showed seasonal peaks corresponding to migratory movements (March‐April and October‐ November); a late spring to early summer occupation of the area by local resident breeders such as Black Guillemot and Common Eider; and a low summer abundance when migrants are not present and individuals of local breeding species such as gulls and cormorants move out of the area. Number of species observed per survey ranged from a low of five species in early September and early December 2016; to a high of 17 species per survey in mid‐April 2017. Abundance ranged from a low of 1.8 birds per half‐hour on October 17, 2016 to a high of 267.8 birds per 30‐minute period on April 17, 2017.
Fewer species of seabirds and water‐associated birds visited the site than in the surveys conducted at the site in 2010‐2012, both in total numbers observed (32 versus 45) and average number per survey. Common and abundant species in 2016‐2017 were the same ones as in the earlier surveys, with the exception of Northern Gannet which was nearly absent this year, occurring in only one survey. Abundance was similar to earlier surveys but the peak abundance during the spring 2017 migration (April 17, 2017) was the highest of any observed at the site, when high numbers of Red‐throated Loon and Black Scoter, concurrently with high numbers of Double‐crested Cormorant, visited the area.
Birds showed moderate and about equal utilization of survey subareas including the ‘Crown Lease’ and areas east of it around Black Rock. Black Rock was a focal point for bird activity, with birds typically roosting on and otherwise using it as a stopover for longer flights; for nesting (e.g. Black Guillemot); or as a base for local feeding in the adjacent waters at various times. During migration peaks, however, birds moving through the area over the water dominated numbers using Black Rock. Since environmental monitoring at the Minas Passage site began in 2009, 50 species of water‐associated birds and shorebirds have been seen in the vicinity of the Tidal Energy Demonstration Site (Minas Basin, Minas Passage & Minas Channel), the majority in Minas Passage specifically at the demonstration site, as the result of shore‐based surveys.
Three species of marine mammal, the Harbour Porpoise (Phocoena phocoena), Harbour Seal (Phoca vitulina) and Harp Seal (Pagophilus groenlandicus) were observed during the year. Seal sightings were rare with three Harbour Seal noted on two surveys and a single Harp Seal on the January 2017 survey. Harbour Porpoise (Phocoena phocoena) occurred occasionally. Twenty‐one Harbour Porpoise were seen at the site, principally from early summer to early fall, with highest numbers detected in September‐October, and individuals most commonly observed in the tidal stream outside Black Rock and the Crown Lease area, south and southwest of Black Rock. Porpoise typically moved with the tidal current, westerly with the ebb tide (out‐going) and easterly with the incoming tide, typically in the tidal stream outside Black Rock and extending through the Crown Lease and inshore areas in the direction of the tidal stream.