Summertime has been busy for our staff here at CVWMA, also for all the resident and migratory populations of wildlife that bring new life to the wetlands. The young of year are now moving towards the next season of growth, migration, and survival. Waterfowl are starting to arrive and move through the wetlands as well, so make sure to look to the sky periodically and notice who is passing by.
We welcomed Living Lakes Canada’sBiodiversity East Kootenay/Columbia Wetlands Field School for two days of workshops at our Administration Office in early August. It was a pleasure to be able to attend and participate in some of the presentations and discussions to a small group of eager young-career participants. Knowledgeable professionals also provided unique hands-on field skill opportunities for participants to engage in and gain field work experience. Thanks to Jessica Holden, Isobel Phoebus, Jared Hobbs, and Norman Allard Jr. for including CVWMA staff for the presentations.
Included in this August summary is an update on the double-crested cormorant and great blue heron rookery monitoring from Julia Shewan, our Conservation Programs Assistant, as well as a reminder to “give bats some space”. Finally, CVWMA is seeking proposals for the use of the West Meadows Farm south of Duck Lake for agricultural purposes – see details and the link provided below.
Soak in the slower days of September and the bounty of what this beautiful valley offers at this time of year.
Kindly,
Alyson Brda
CVWMA Office Administrator
A Tail of Two Neighbours
Article by: Julia Shewan, CVWMA Conservation Programs Assistant
This year’s rookery counts are now complete! We completed our aerial drone survey earlier in June this year and we now just crunched the numbers. This year marks the 12th year we have completed this monitoring at the double-crested cormorant and great blue heron rookery in Leach Lake. The monitoring continues despite our having surpassed the 10-yr monitoring commitment to provide cormorant nest counts to the United States Pacific Flyway Non-Game Technical Committee. We will continue the monitoring as often as resources allow given the conservation value of this feature. Double-crested cormorant and great blue heron are both Blue-listed species in the province, a conservation status that indicates they are particularly sensitive to human activities or natural events. Furthermore, the Leach Lake rookery is one of the only known colonies for either species in the Creston Valley. As such, ongoing monitoring can provide a snapshot of how the local population is faring.
Our aerial survey was completed on June 23, in line with previous years’ survey timing around the summer solstice. We assessed there were 243 cormorant and 30 heron nests present when we reviewed the images collected from the drone. Keen readers will know these numbers represent an increase for cormorants and a decrease for herons from last year. Nest counts have cycled in past years, and 2026 counts are within the bounds of previous years’ variation. But the numbers alone don’t reveal the true picture of how the colony is changing over time. Nesting location is changing, and our survey and data analysis methodology permits us to track these changes.
Leach Lake rookery as seen from the air
There has been a concerted shift in nesting away from the riverside in both species, which is where the birds originally settled when the colony was established circa 2010 at that location. At this point, both species have concentrated their nesting to the strip of cottonwood trees at the inland edge of the riparian area, as far away from the river as they can get! The herons started the inland shift, likely to avoid nesting next to an increasing number of cormorants, though over time the cormorants have followed the herons inland. It seems like a not-so-subtle hint among neighbours was not taken!
Nest sites are more visible than ever before to those who journey further afield in Leach Lake; visitors will know you needed to be eagle-eyed to spot even one nest just a few years back. The “improved” visibility of nests stems (pun intended!) from the fact that the nesting trees become defoliated as feces from adults and nestlings accumulate over time. Many trees end up dying with repeated years of use. The dead trees do continue to provide nesting habitat, though over time limbs and branches are lost and eventually some trees fall down. As a result, nest sites have continually less visual obscurement as the trees die back and fall over. This process of defoliation and subsequent tree death has decreased the overall amount of suitable nesting habitat for both species across the entire colony boundary. Formerly occupied areas have not yet had time to recover and now there is an ever-shrinking amount of suitable habitat left in the current colony centre. While we have seen some individuals adapt and nest at the fringes of the current colony centre, there does not appear to be a concerted shift to these outer edges as of yet.
It’s for this reason (amongst others) that makes Leach Lake rookery monitoring so interesting and valuable to continue. We want to know where the herons will nest once their former stronghold, where they had nested in relatively high numbers just a few years ago, is continually taken over by cormorants. Likewise, what will the cormorants do as their nesting habitat shrinks? An outward expansion from the current colony boundary is possible. Or, we may see a larger scale shift where the entire colony is abandoned in favour of a brand new location. Such a largescale shift has happened in the past, whereby birds shifted roughly a kilometre northwest from their original colony to the current colony between 2010 and 2013. Either way, it is interesting to watch the dynamics of these two nesting neighbours. Until next year!
It’s dusk, I am outside in my yard close to the creek, enjoying the late summer evening and then I notice something speed by me silently, and in a flash it’s gone. Then another, and another, and soon my eyes adjust and I can see it is feeding time for our bat friends. As humans, we can sometimes think of a big bug hatch as a nuisance, but if you can think like a bat, it’s an exciting evening buffet! I wonder which kind of bats they are in our yard, and interestingly these little guys could be a number of different species, because in the province of BC we have 15 species, 12-13 of which can be found in the Creston Valley! This is the most diversity of bats in Canada! Sadly though, many of these bats are endangered due to habitat loss, disease and human disturbance. This is all the more reason to be aware of these residents in our yards and the environment around us and respect them. In the later part of the summer, bats are on the move, and it could be more likely that you will see them around.
It is very important to remember to leave bats alone. Give them space and never try to pick them up or handle them. Keeping your distance is safer for humans, pets, and the bats alike. Less then 0.05% of bats carry rabies. If you or someone you know has questions, concerns, or want to learn more and help bats, you can check out the BC Community Bat Program website. This is an excellent resource for all things bats!
Creston Valley Wildlife Management Authority is currently offering to interested persons, an opportunity to participate in the CVWMA Agricultural Land Use Permit Request for Proposals – West Meadows Farm.
Please read fully and fill in all application package as follows, and submit to the CVWMA no later than submission deadline of Sept 25, 2026.
Interested candidates must register and attend a mandatory field visit on Friday, September 4th, 2026, from 9:30-11:30. Meeting location to be determined.
Please, call the CVWMA office at 250-402-6900 to register for this field visit.
Questions and inquiries can be sent via email to askus@crestonwildlife.ca, or please call the CVWMA Administration office 250-402-6900.
THANK YOU to all who support CVWMA and believe in our mission to manage the Creston Valley Wildlife Management Area for conservation and natural species diversity through active habitat and wildlife management, research and education!
CVWMA is a federally registered Charity.Donate Now,though our website, and an official receipt will be issued to you for tax purposes.
