Brock Lake
Grebe Survey Summary
- Max Adults: 6
- Year: 2006
- Most Recent Adults: 6
- Year: 2011
- Survey Type: Shore; Boat; Air
- Most Common Threats Reported: N/A
- Lake name:
- Brock Lake
- Location:
- Alberta
- Latitude:
- 53.8141667
- Longitude:
- -114.8433333
- Basin type:
- non-reservoir
- Management agency:
- Alberta Parks
- Region associations:
- Prefontaine Brock Lakes Natural Area
- Designations:
- Natural Area
- Comments:
- Part of Prefontaine Brock Lakes Natural Area.
Surveys (3)
Survey Citation:
COSEWIC. 2014. COSEWIC assessment and status report on the western grebe (Aechmophorus occidentalis) in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. 55 pp. www.registrelep-sararegistry.gc.ca/default_e.cfm
-
Type
shore; boat; air -
Time period
1991, 2011 -
Source
Report -
Both Western and Clarks?
N
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 1 to 100 | 6 | 1991-2011 |
| Most Recent Adults | 1 to 100 | 6 | 2011 |
| Max Nests | N/A | N/A | N/A |
| Most Recent Nests | N/A | N/A | N/A |
| Max Chicks | N/A | N/A | N/A |
| Most Recent Chicks | N/A | N/A | N/A |
Comments:
From Table A.2, maximum counts of breeding Western grebes from surveys mostly conducted during nesting season from June and July from 1991 to 2011 (sourced from Wilson, A. and Smith, P.A. 2013. Distribution and population status of Western Grebes in Canada. Unpublished report for the Canadian Wildlife Service). No break out of data per year or other details.
Survey Citation:
Erickson, M. E. 2010. Persistence and abundance of the western grebe in Alberta. Dissertation. University of Alberta. Edmonton, Alberta, Canada. Same lakes and abundance estimated were checked against Erickson, M. E., C. Found-Jackson, and M. S. Boyce. 2017. Habitat associations with counts of declining western grebes in Alberta, Canada. Avian Conservation and Ecology. 12(1):12. Appendix to Erickson et al 2014 is unavailable but presumed to be the same list of lakes and abundance estimates.
-
Type
shore -
Time period
27 May 2008, 25 August 2008 -
Source
Dissertation -
Both Western and Clarks?
N
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 1 to 100 | 6 | 2006 |
| Most Recent Adults | 0 | 0 | 2008 |
| Max Nests | N/A | N/A | N/A |
| Most Recent Nests | N/A | N/A | N/A |
| Max Chicks | N/A | N/A | N/A |
| Most Recent Chicks | N/A | N/A | N/A |
Comments:
From Table B.1 and Table C.1, survey methods and dates for 2008 field season, and latest abundance estimate from 2008, compared to maximum abundance estimate. Source of maximum abundance estimate is from 2006 sourced from Alberta Sustainable Resource Development Species at Risk (SAR) #121. I didn't include maximum abundance estimate as part of the survey date for Erickson's surveys.
Survey Citation:
Hanus, S., L. Wilkinson, and H. Wollis. 2002. Western (Aechmophorus occidentalis) and Eared (Podiceps nigricollis) grebes of Central Alberta: 2002 field season summary. Alberta Sustainable Resource Development, Fish and Wildlife Division, Alberta Species at Risk Report Number 60. Edmonton, Alberta, Canada.
-
Type
boat -
Time period
27 June 2002 -
Source
Report -
Both Western and Clarks?
N
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 1 to 100 | 5 | 2002 |
| Most Recent Adults | 1 to 100 | 5 | 2002 |
| Max Nests | 0 | 0 | 2002 |
| Most Recent Nests | 0 | 0 | 2002 |
| Max Chicks | N/A | N/A | N/A |
| Most Recent Chicks | N/A | N/A | N/A |
Comments:
Colony was not found. The small number of adults was a new sighting for this lake.