CLBMON-36: Kinbasket and Arrow Lakes Reservoirs: nest mortality of migratory birds due to reservoir operations
Author: C. Craig, R. Gill, J.M. Cooper
Assess nest mortality of bird species in Kinbasket Reservoir and Revelstoke Reach in Arrow Lakes Reservoir. CLBMON-36 is a 10-year project addressing knowledge gaps related to the management of reservoirs (their drawdown zone habitat and their operations) to enhance avian productivity and minimize incidental destruction of nests caused by reservoir operations.
Since 2008, there have been 209 nest failures (of 36 species) observed as a direct consequence of reservoir operations (Table 3-4); 26 nests (8 species) in KIN, and 183 nests (35 species) in ALR. At KIN, nest inundation was observed in every year except 2008, 2009, and 2014; at ALR, nest inundation was observed in every year except 2015.
Being positioned near the head of the Columbia River and having a huge capacity for storage, the KIN water level traditionally reaches its annual maximum later in the year compared with the ALR. However, as in 2015 and 2016, KIN filled unusually early in 2017, leading to greater nest flooding impacts than in earlier years.
Like Year 9, Year 10 was marked by higher than normal nest flooding in both KIN and ALR. Although we have witnessed relatively high nest flooding impacts in KIN for the past three years, the impact is still relatively low compared to ALR.
In the summer of 2017, ALR’s peak elevation was comparatively high, at 439.57 m ASL, though it reached this peak a bit later in the season than in other high-water years such as 2008, 2012, and 2013. The higher water levels in 2017 results in greater nest flooding impacts than in the two previous years. At ALR we have observed a high variability in annual maximum water elevation during the study.
To date, we have observed that nest flooding is a factor affecting productivity for 37 species, mostly in ALR. Qualitatively, our impression at the ALR is that species that nest in low elevation habitats in the reservoir drawdown zone (e.g., SAVS, Western Meadowlark (Sturnella neglecta), SEOW), and those nesting directly on the ground (e.g., dabbling ducks and shorebirds), have higher chances of nest submersion, and are uncommon. These populations may be limited by reservoir operations and could increase if nest flooding was not an issue. We have previously shown that nest flooding is also an important issue for species nesting in emergent vegetation (e.g., rails, grebes, blackbirds (CBA 2013, 2015a, 2015b)). Species nesting in shrubs commonly suffer from nest flooding in the ALR, but this impact is compensated to some degree by reduced nest predation for nests positioned over water (van Oort et al. 2015).
Since 2008, there have been 209 nest failures (of 36 species) observed as a direct consequence of reservoir operations (Table 3-4); 26 nests (8 species) in KIN, and 183 nests (35 species) in ALR. At KIN, nest inundation was observed in every year except 2008, 2009, and 2014; at ALR, nest inundation was observed in every year except 2015.
Being positioned near the head of the Columbia River and having a huge capacity for storage, the KIN water level traditionally reaches its annual maximum later in the year compared with the ALR. However, as in 2015 and 2016, KIN filled unusually early in 2017, leading to greater nest flooding impacts than in earlier years.
Like Year 9, Year 10 was marked by higher than normal nest flooding in both KIN and ALR. Although we have witnessed relatively high nest flooding impacts in KIN for the past three years, the impact is still relatively low compared to ALR.
In the summer of 2017, ALR’s peak elevation was comparatively high, at 439.57 m ASL, though it reached this peak a bit later in the season than in other high-water years such as 2008, 2012, and 2013. The higher water levels in 2017 results in greater nest flooding impacts than in the two previous years. At ALR we have observed a high variability in annual maximum water elevation during the study.
To date, we have observed that nest flooding is a factor affecting productivity for 37 species, mostly in ALR. Qualitatively, our impression at the ALR is that species that nest in low elevation habitats in the reservoir drawdown zone (e.g., SAVS, Western Meadowlark (Sturnella neglecta), SEOW), and those nesting directly on the ground (e.g., dabbling ducks and shorebirds), have higher chances of nest submersion, and are uncommon. These populations may be limited by reservoir operations and could increase if nest flooding was not an issue. We have previously shown that nest flooding is also an important issue for species nesting in emergent vegetation (e.g., rails, grebes, blackbirds (CBA 2013, 2015a, 2015b)). Species nesting in shrubs commonly suffer from nest flooding in the ALR, but this impact is compensated to some degree by reduced nest predation for nests positioned over water (van Oort et al. 2015).
Resources Data:
Name: CLBMON-36-YR10-2018-05-03
Format: PDF
URL: https://www.bchydro.com/content/dam/BCHydro/customer-portal/documents/corporate/environment-sustainability/water-use-planning/southern-interior/clbmon-36-yr10-2018-05-03.pdf
Additional Info
Study Years: 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018
Published: 2018
Topics
Tags: Arrow Lakes Reservoir, BC Hydro, Bombycilla Cedrorum, British Columbia, Cedar Waxwing, Habitat Distribution, Habitat Suitability, Juvenile Survivorship, Kinbasket Reservoir, Nest Flooding, Nest Monitoring, Nest Mortality, Nest Survivorship, Passerculus Sandwichensis, Reservoir Operations, River Regulation, Savannah Sparrow, Setophaga Petechia, Wildlife, Yellow WarblerCLBMON-36: Kinbasket and Arrow Lakes Reservoirs: nest mortality of migratory birds due to reservoir operations
Author: C. Craig, R. Gill, J.M. Cooper
Tags: Arrow Lakes Reservoir, BC Hydro, Bombycilla Cedrorum, British Columbia, Cedar Waxwing, Habitat Distribution, Habitat Suitability, Juvenile Survivorship, Kinbasket Reservoir, Nest Flooding, Nest Monitoring, Nest Mortality, Nest Survivorship, Passerculus Sandwichensis, Reservoir Operations, River Regulation, Savannah Sparrow, Setophaga Petechia, Wildlife, Yellow Warbler
Assess nest mortality of bird species in Kinbasket Reservoir and Revelstoke Reach in Arrow Lakes Reservoir.
CLBMON-36 is a 10-year project addressing knowledge gaps related to the management of reservoirs (their drawdown zone habitat and their operations) to enhance avian productivity and minimize incidental destruction of nests caused by reservoir operations.
Summary
Since 2008, there have been 209 nest failures (of 36 species) observed as a direct consequence of reservoir operations (Table 3-4); 26 nests (8 species) in KIN, and 183 nests (35 species) in ALR. At KIN, nest inundation was observed in every year except 2008, 2009, and 2014; at ALR, nest inundation was observed in every year except 2015.
Being positioned near the head of the Columbia River and having a huge capacity for storage, the KIN water level traditionally reaches its annual maximum later in the year compared with the ALR. However, as in 2015 and 2016, KIN filled unusually early in 2017, leading to greater nest flooding impacts than in earlier years.
Like Year 9, Year 10 was marked by higher than normal nest flooding in both KIN and ALR. Although we have witnessed relatively high nest flooding impacts in KIN for the past three years, the impact is still relatively low compared to ALR.
In the summer of 2017, ALR’s peak elevation was comparatively high, at 439.57 m ASL, though it reached this peak a bit later in the season than in other high-water years such as 2008, 2012, and 2013. The higher water levels in 2017 results in greater nest flooding impacts than in the two previous years. At ALR we have observed a high variability in annual maximum water elevation during the study.
To date, we have observed that nest flooding is a factor affecting productivity for 37 species, mostly in ALR. Qualitatively, our impression at the ALR is that species that nest in low elevation habitats in the reservoir drawdown zone (e.g., SAVS, Western Meadowlark (Sturnella neglecta), SEOW), and those nesting directly on the ground (e.g., dabbling ducks and shorebirds), have higher chances of nest submersion, and are uncommon. These populations may be limited by reservoir operations and could increase if nest flooding was not an issue. We have previously shown that nest flooding is also an important issue for species nesting in emergent vegetation (e.g., rails, grebes, blackbirds (CBA 2013, 2015a, 2015b)). Species nesting in shrubs commonly suffer from nest flooding in the ALR, but this impact is compensated to some degree by reduced nest predation for nests positioned over water (van Oort et al. 2015).