Blacketts Lake
| Blacketts Lake | |
|---|---|
 Starr Island on Blacketts Lake | |
  Blacketts Lake Location of Blacketts Lake in Nova Scotia | |
| Location | Cape Breton Regional Municipality, Nova Scotia |
| Coordinates | 46°4′7″N 60°18′28″W / 46.06861°N 60.30778°W |
| Type | Freshwater lake |
| Upper Sydney River system; Gillis Lake[1] | |
| Sydney River | |
| Basin countries | Canada |
Surface area | 172 ha (430 acres)[2] |
Average depth | 9.5 m (31 ft)[2] |
| Max. depth | 30 m (98 ft)[2] |
Water volume | 16,400,000 m3 (580,000,000 cu ft)[2] |
Shore length1 | 2.4 km (1.5 mi)[2] |
| Islands | Starr Island |
| 1 Shore length is not a well-defined measure. | |
Blacketts Lake is a freshwater lake and unincorporated community in the Cape Breton Regional Municipality, Nova Scotia, Canada. The community is in the upper Sydney River watershed, of which the lake forms the headwaters. It had a population of 270 in the 2001 census.[3] The lake and its connected waters contain the northernmost known population of the yellow lampmussel (Lampsilis cariosa).[4]
Characteristics
[edit]Blacketts Lake lies in the upper Sydney River system and is connected to Gillis Lake. Flow through the lake is generally imperceptible except near the road bridge and causeway on Blacketts Lake Road. During winter, most of the lake freezes, although areas of faster flow near the bridge and the mouths of brooks may remain open.[4]
Published measurements differ by survey and methodology. The federal yellow lampmussel management plan reports a surface area of 187 ha (460 acres), while a Nova Scotia lake survey completed in July 2018 calculated a surface area of 172 ha (430 acres).[4][2] An earlier provincial lake-inventory map gives a maximum depth of approximately 25 m (82 ft), whereas the 2018 survey recorded approximately 30 m (98 ft).[5][2] The 2018 survey measured a mean depth of 9.5 m (31 ft), a volume of approximately 16,400,000 m3 (580,000,000 cu ft) and a shoreline length of approximately 2.4 km (1.5 mi).[2]
The same survey recorded a surface pH of 7.8, total phosphorus of approximately 0.003 mg/L and chlorophyll a of approximately 2.4 mg/m3. The lake stratifies thermally during summer.[2] The alkaline conditions in the upper Sydney River watershed reflect the area's calcareous geology.[6]
Hydrology and water use
[edit]The lake is dammed at its outlet to the Sydney River. A fish ladder at the dam allows fish to move between the river and the lake.[1] The lake was formerly a primary drinking-water source and later served as a backup water supply for the Cape Breton Regional Municipality and as an industrial water supply.[1]
Sydney and neighbouring communities now obtain their municipal water chiefly from the Middle Lake Road Wellfield, a groundwater system commissioned in 1996.[7]
Climate
[edit]Blacketts Lake does not have a long-term weather station. The nearest long-term records are from the Sydney area. The regional climate is humid continental and strongly influenced by the Atlantic Ocean, with cool summers, wet and windy winters, substantial snowfall and precipitation throughout the year.[8]
Ecology
[edit]Yellow lampmussel
[edit]Blacketts Lake and its connected waters contain a substantial part of the Nova Scotia population of the yellow lampmussel. The Sydney River population is the northernmost known population of the species. In Canada, the mussel is known from Nova Scotia and New Brunswick.[4][1]
The yellow lampmussel is listed as a species of special concern on Schedule 1 of the federal Species at Risk Act and as threatened under the Nova Scotia Endangered Species Act.[1] The 2022 provincial recovery plan estimated that the Blacketts Lake subpopulation represented approximately 38% of the known Nova Scotia population.[1]
The mussel requires a fish host during its larval stage. Field studies in the Sydney River system have confirmed white perch (Morone americana) as its host fish in Nova Scotia.[6][9]
Across its wider range on the Atlantic slope of North America, the yellow lampmussel is declining. A 2025 review identified habitat alteration, barriers, invasive species, pollution and gaps in knowledge about host fishes and population trends among the species' conservation concerns.[10]
Fish and invasive species
[edit]Ten species of native freshwater fish have been recorded in the Sydney River system, including brook trout, white perch, American eel and Atlantic salmon.[6]
Chain pickerel (Esox niger) was introduced illegally to Blacketts Lake around 2010 and subsequently became established in Blacketts Lake, Gillis Lake and the upper Sydney River.[1] Chain pickerel prey on white perch, reducing the availability of the lampmussel's larval host. Surveys conducted in 2018 and 2019 found no evidence of recent yellow lampmussel recruitment in Blacketts Lake, and the provincial recovery plan described the subpopulation as potentially non-reproductive.[1]
Muskrats (Ondatra zibethicus) are the principal predators of adult yellow lampmussels in the Sydney River system. Although muskrat predation is generally considered a limited threat to healthy mussel populations, it may have greater importance at Blacketts Lake because of the lack of recent recruitment.[4][1]
Conservation and research
[edit]Conservation research in the Sydney River watershed has examined yellow lampmussel population structure, host-fish relationships, invasive chain pickerel, muskrat predation, fish passage and methods for detecting freshwater mussels.[9] Research reported by Fisheries and Oceans Canada found that chain pickerel predation contributed to declines in white perch abundance, while Cape Breton University studies confirmed white perch as the mussel's host fish in Nova Scotia.[9]
Research has also examined food-web relationships among chain pickerel, yellow lampmussel and small-bodied rainbow smelt, and has evaluated environmental DNA as a possible method for detecting freshwater mussels.[9] Fish ladders at the Sydney River dam were repaired following assessments of fish passage.[9]
Federal and provincial recovery documents identify continued monitoring, prevention of further aquatic invasive-species introductions, protection of shoreline habitat and water quality, and assessment of possible conservation interventions as priorities. Because recruitment has not recently been detected at Blacketts Lake, possible measures discussed for future evaluation include host-fish stocking, habitat and fish-passage improvements, management of chain pickerel and translocation of mussels to suitable habitat.[1][9]
History and naming
[edit]The lake lies on an ancient Mi'kmaq canoe portage route connecting East Bay on the Bras d'Or Lake with Sydney Harbour by way of the Sydney River. The nearby community of Portage takes its name from the same approximately 3.5-kilometre (2.2 mi) crossing, whose Mi'kmaq name was recorded as Tewitnochk and later rendered as "Tweednooge".[11]
The lake has been known by several names. It was called Portage Lake after the canoe route, Barn Lake after the barn of an early settler named Ingoville, and Forks Lake before receiving its present name from the Blackett family, who lived on its shores.[12]
According to a family history published in Cape Breton's Magazine, William Blackett was sent from England by the British government in the 1780s to purchase timber for English shipyards and settled on Prince Edward Island. His son Walter Blackett later obtained a Crown land grant on the upper Sydney River and established a homestead there.[13]
The present lake is largely artificial. The Sydney River was dammed in 1902, flooding the valley above the dam and converting the former tidal reach of the river into a freshwater lake.[6] A local family account similarly describes the flooding of riverside meadow and small islands as industrial development proceeded downstream.[13]
Community
[edit]The official geographical name of the community is Blacketts Lake. The Canadian Geographical Names Database also records "Blackett Lake" as the former official name of a local post office.[14]
The community had a population of 270 when it was enumerated as a designated place in the 2001 census.[3] This figure is historical and should not be interpreted as a current population estimate.
See also
[edit]References
[edit]- 1 2 3 4 5 6 7 8 9 10 Nova Scotia Department of Natural Resources and Renewables (October 2022). Recovery Plan for the Yellow Lampmussel (Lampsilis cariosa) in Nova Scotia (PDF) (Report). Nova Scotia Endangered Species Act Recovery Plan Series. Retrieved 11 July 2026.
- 1 2 3 4 5 6 7 8 9 "Nova Scotia Lake Chemistry Data (Blacketts Lake, site 2, Sydney R.)". Nova Scotia Lake Survey. Government of Nova Scotia. doi:10.25976/r2b8-7966. Retrieved 11 July 2026.
- 1 2 Statistics Canada (2002). "2001 Community Profiles: Blacketts Lake, Nova Scotia (designated place)". Statistics Canada. Retrieved 11 July 2026.
- 1 2 3 4 5 Fisheries and Oceans Canada (2010). "Management Plan for the Yellow Lampmussel (Lampsilis cariosa) in Canada". Environment and Climate Change Canada. Retrieved 11 July 2026.
- ↑ Blacketts Lake, Cape Breton County (PDF) (Map). Nova Scotia Fisheries and Aquaculture. Retrieved 11 July 2026.
- 1 2 3 4 COSEWIC (2004). COSEWIC assessment and status report on the Yellow Lampmussel Lampsilis cariosa in Canada (Report). Ottawa: Committee on the Status of Endangered Wildlife in Canada. Retrieved 11 July 2026.
- ↑ "Source Water Protection". Cape Breton Regional Municipality. Retrieved 11 July 2026.
- ↑ "Sydney A, Nova Scotia — Canadian Climate Normals 1991–2020". Canadian Climate Normals. Environment and Climate Change Canada. Retrieved 11 July 2026.
- 1 2 3 4 5 6 Fisheries and Oceans Canada (2025). "Yellow Lampmussel (Lampsilis cariosa), 2015 to 2022: progress report of management plan implementation". Environment and Climate Change Canada. Retrieved 11 July 2026.
- ↑ Farrington, Stefanie J.; Murphy, Christina A.; Perkins, David; Roy, Allison H. (2025). "Range-wide ecology, conservation, and research needs for yellow lampmussel (Lampsilis cariosa)". Hydrobiologia. 852 (11): 2729–2754. doi:10.1007/s10750-024-05765-2.
- ↑ Fergusson, C. Bruce (1967). Place-Names and Places of Nova Scotia. Halifax: Public Archives of Nova Scotia. p. 182.
- ↑ Brown, Thomas J. (1922). Place-names of the Province of Nova Scotia. Halifax: Royal Print & Litho. p. 146.
- 1 2 Kennedy, Isabel Blackett (1991). "Mystery at Blackett's Lake". Cape Breton's Magazine. No. 55. Retrieved 11 July 2026.
- ↑ "Blacketts Lake". Canadian Geographical Names Database. Natural Resources Canada. Retrieved 11 July 2026.
External links
[edit]- Blacketts Lake bathymetric and lake-inventory map — Nova Scotia Fisheries and Aquaculture
- Yellow lampmussel management plan — Government of Canada
- Recovery Plan for the Yellow Lampmussel in Nova Scotia — Government of Nova Scotia