Union Reservoir (Calkins Lake)
Grebe Survey Summary
- Max Adults: 150
- Year: 2010
- Most Recent Adults: 150
- Year: 2010
- Survey Type: Shore; Boat
- Most Common Threats Reported: N/A
- Lake name:
- Union Reservoir (Calkins Lake)
- Location:
- Colorado
- Latitude:
- 40.1822163
- Longitude:
- -105.0390504
- Surface area (km2):
- 2.9
- Basin type:
- reservoir
- Dam completion date:
- 1903 tunnel
- Management agency:
- City of Longmont
- Lake use:
- water supply
- Comments:
- The 1903 tunnel construction made Union Reservoir (Calkins Lake) into a reservoir.
Surveys (5)
Survey Citation:
Giroir, G.P. and T. Leukering. 1999. Breeding distribution and numbers of Eared, Western, and Clark's grebes in Colorado. J. Colorado Field Ornithologists 33:83-90.
-
Type
shore -
Time period
23 May 1998, 28 July 1998 -
Source
Occasional Paper -
Both Western and Clarks?
Y
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 101 to 500 | 120 | 1998 |
| Most Recent Adults | 101 to 500 | 120 | 1998 |
| Max Nests | N/A | N/A | N/A |
| Most Recent Nests | N/A | N/A | N/A |
| Max Chicks | 1 to 100 | 51 | 1998 |
| Most Recent Chicks | 1 to 100 | 51 | 1998 |
Comments:
One of 93 lakes, ponds, and reservoirs surveyed in CO for 3 species of grebes.
Survey Citation:
Cavitt, J. F., S. L. Jones, N. M. Wilson, J. S Dieni, T. S. Zimmerman, R. H. Doster, and W. H. Howe. 2014. Atlas of breeding colonial waterbirds in the interior western United States. Research Report, U.S. Department of the Interior, Fish and Wildlife Service, Denver, Colorado.
-
Type
shore -
Time period
25 July 2010 -
Source
Report -
Both Western and Clarks?
Y
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 101 to 500 | 150 | 2010 |
| Most Recent Adults | 101 to 500 | 150 | 2010 |
| 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:
Miller is observer. Conducted as part of Western Colonial Waterbird Survey (WCWS), a breeding survey of 18 species from May to July 2009 to 2011, resulting in this Atlas. Survey dates given here are the only dates provided.
Survey Citation:
Ely, David. 1999. News from the field: the summer 1998 report (June and July). 33(1): 69-76. Published by the Journal of Colorado Field Ornithologists.
-
Time period
14 July 1998 -
Source
Notes -
Both Western and Clarks?
N
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 1 to 100 | 36 | 1998 |
| Most Recent Adults | 1 to 100 | 36 | 1998 |
| Max Nests | N/A | N/A | N/A |
| Most Recent Nests | N/A | N/A | N/A |
| Max Chicks | 1 to 100 | presence | 1998 |
| Most Recent Chicks | 1 to 100 | presence | 1998 |
Comments:
Observed 18 pairs with young, no exact brood counts given nor indication of how many pairs had young.
Survey Citation:
Ely, David. 1999. News from the field: the summer 1998 report (June and July). 33(1): 69-76. Published by the Journal of Colorado Field Ornithologists.
-
Time period
14 July 1998 -
Source
Notes -
Both Western and Clarks?
N
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 1 to 100 | 60 | 1998 |
| Most Recent Adults | 1 to 100 | 60 | 1998 |
| Max Nests | N/A | N/A | N/A |
| Most Recent Nests | N/A | N/A | N/A |
| Max Chicks | 1 to 100 | presence | 1998 |
| Most Recent Chicks | 1 to 100 | presence | 1998 |
Comments:
Observed 30 pairs with young, no exact brood counts given nor indication of how many pairs had young.
Survey Citation:
Beason, J., R. Levad, and T. Leukering. 2005. Monitoring Colorado’s Birds: The 2004 field season report. Rocky Mountain Bird Observatory unpub. report. __ pp.
-
Type
boat -
Time period
2004 -
Source
Report -
Both Western and Clarks?
N
| Count Type | Range | Max | Year |
|---|---|---|---|
| Max Adults | 1 to 100 | presence | 2004 |
| Most Recent Adults | 1 to 100 | presence | 2004 |
| Max Nests | 1 to 100 | 2 | 2004 |
| Most Recent Nests | 1 to 100 | 2 | 2004 |
| Max Chicks | N/A | N/A | N/A |
| Most Recent Chicks | N/A | N/A | N/A |
Comments:
Per authors, active nest count = # nests detected + 0.5*(juveniles detected). One of only 2 sites with active nesting in 2004. Surveys were conducted from 1998 to 2004 for this report but since only nests counted in 2004 were mentioned for this lake, I noted this for just 2004.