Comprehensive Site Development Plan ... - City of Kelowna

Avocets at Glenmore Landfill
5
There is considerable time (5-10 years) before the remaining wetlands in the Glenmore Landfill
are needed for landfill purposes. This gives us the comfort of having a number of years to attempt
to encourage the colony to move to offsite habitats. As that scenario would be by far the most
cost-effective mitigation scenario, considerable effort should be made to make that occur.
Another reason to encourage the movement of the colony to an offsite location is that although
American Avocets presently breed successfully at the Glenmore Landfill, there are no guarantees
that as the landfill expands they will not abandon the site due to disturbance, or as conditions
change.
If a colony becomes established at Robert Lake, or other wetlands, whether or not avocets
continue to nest at the Glenmore Landfill, then the danger of extirpation in the Okanagan valley
becomes diminished. This hoped-for result would give resource managers short term comfort
while planning for long term conservation of avocets, and a long-term option to perhaps more
fully develop the Glenmore Landfill as pressure to expand the landfill increases, without
endangering the Okanagan avocet population.
3.2 Alternative breeding habitat at Slough No. 2 and Bubna Slough
At the same time as habitat enhancement work is being conducted at Robert Lake, a few nesting
platforms should be installed at Slough No. 2 and Bubna Slough. These wetlands have not been
used by avocets previously, but it would be an inexpensive experiment and, if successful, would
provide additional conservation options.
3.3 Potential for off-site mitigation at Robert Lake
Robert Lake is regularly used for foraging and nesting occurred once. There appears to be ample
shoreline to support a breeding colony of American Avocets. This shoreline currently attracts a
number of migrant and local avocets to forage. Clusters of artificial floating nesting islands
might be used to stimulate colony development, but this would have to be tested before this could
be relied on as a mitigation method. These might be preferable to constructing permanent low
islands with 12:1 side slopes on public land or rights-of-way in the lake as water levels cannot be
controlled at the present time. Permanent islands might be flooded in some years, and connected
to the mainland in other years, thereby becoming unsuitable for nesting avocets. However, there
are water management options that could control water levels, if all stakeholders agreed.
Unless private owners were amenable to making portions of land available, the best option on
public land for construction of permanent islands would be for a single island (0.07 ha or 30-m
diameter) in the south west corner. That part of Robert Lake is presently owned by Central
Okanagan Regional District and could be managed as parkland (Weir and Gyug 1999).
3.4 Maintain existing wetland habitat at the Glenmore Landfill for breeding
avocets
While attempts to encourage the breeding colony to move elsewhere are underway, it is
imperative that the existing wetland at the Glenmore Landfill is retained. It may be necessary to
manage water levels in such a way as to make the landfill site less desirable s nesting habitat than
usual, but the wetland should be retained in such a condition that it could be restored to a suitable
condition quickly.
Manning, Cooper and Associates