The Herons Have Returned! Local heron enthusiast and CENC staff member Anna Scouten reported seeing several heron scouts on Feb 17th investigating the heron rookery. In past years within a week a larger “siege” of herons has returned in full to begin another noisy, raucous nesting season. This has proved true again this year with a number of herons returning to the rookery in the last weekend of February.
This is perfect timing for you to click onto our Live heron Cam below and zoom around the rookery to see if you can spot our returning families. Enjoy!
To activate the camera click on the screen above. Maximize the view by clicking the square in the bottom right hand corner. Take control of the camera for 5 minutes by clicking the blue “control” toggle in the bottom right hand corner of the screen. Enjoy!
Pacific Great Blue Herons in the Estuary
Photo by Todd Carnahan
Pacific Great Blue Herons are found throughout British Columbia, near lakes and coastal areas They may nest individually, or in heronries (colonies) with tens or or sometimes hundreds of birds, and typically return to the same nesting areas year after year. Herons lay 2-5 eggs, usually between February and April, which hatch in about 30 days. The parents share the duties of incubating the eggs and feeding the young. At two months old the young are able to fly and seek food. A heron’s diet consists mainly of fish, but they will also eat shellfish, insects, rodents, amphibians (mostly frogs), reptiles and small birds. Herons may live to be 17 or more years old.
Pacific Great Blue Herons are a Blue-listed species; considered vulnerable to disturbance by bald eagles and humans. Urban and rural development results in the loss of suitable nesting areas and disturbance to birds during their breeding season. Especially during the early stages of nesting, unusual events and loud noises such as mechanical chippers, chainsaws, and large trucks may cause the herons to abandon their nests. The Cowichan Bay Heronry in Wessex Ravine is designated as a protected development permit area (DPA) where these noisy activities are prohibited during heron nesting.
So what’s all the fuss about? As we face the two major environmental challenges of our time – the biodiversity and climate crises – a staggering 3 billion birds, close to one in three individuals, have been lost from Canada and the United States since just 1970. Birds Canada names the main threats to birds as “habitat loss, pesticides and contaminants, cats and invasive species, collisions and the climate crisis.” Within this bleak picture, 2019’s State of Canada’s Birds Report offers a glimmer of hope, reporting wetland and waterfowl bird populations are increasing from historic low levels – a success story for conservation partnerships.
Under the BC Wildlife Act, Section 34, the nests and nest trees of herons are protected year-round, whether or not the nest is currently active. Herons and their active nests are also protected under the federal Migratory Birds Convention Act. The Coastal (fannini) subspecies is listed under SARA as “special concern”, and both subspecies are listed as Identified Wildlife.
Our Heronry History
The almost 30-year-old Cowichan Bay heron nesting colony is no stranger to disturbances. In the early 2000s BC Ministry of Environment officials identified and flagged approximately 95 nests tucked into a grove of alders surrounded and protected by a mixed wood forest of conifers and Maples in the Wessex Ravine.
In 2004 a new housing development was planned. The forested area to the south of the heronry was clear-cut to the boundary of the colony leaving the herons’ nests exposed to increased eagle predation and human disturbance. As a result, the herons abandoned that site. But 30 pairs of herons re-nested not far away, deeper in Wessex Ravine and closer to the estuary. The colony at the current site has grown each year.
In 2008 local Cowichan Bay residents came together to successfully advocate for the creation of CVRD Development Permit Bylaw 3083 (now amended to CVRD Bylaw 3605) to protect the ecological attributes and socio-economic values common to this critical habitat and limit activities within a 100m radius of any Great Blue Heron nest trees.
In 2014, this protection was tested during the construction of a condominium complex which came within 30m of the colony. The development was not complete when the herons’ nesting period began. As local heron stewards heard hammering and sawing continuing, concerns heightened. BC Ministry of Forests, Lands, Natural Resource Operations’ staff met with the construction company, environmental consultants and the Cowichan Valley Regional District to put guidelines in place to protect the nesting herons, including noise reduction and disturbance monitoring protocols. They also confirmed Provincial authority to issue a “stop work order” if disturbance was noted, which was used for a brief period. This co-operative approach meant the herons were not significantly disturbed and nested successfully.
In 2017 biologists recommended a heron webcam for monitoring the Cowichan Bay heronry – a perfect location both for science and public education about this species of special concern. The Cowichan Estuary Nature Centre took up the challenge and the rest is history!
Special thanks to talented nature lover Anais MacPherson (10yrs old) for this beautiful ink and watercolour painting!
We hope it inspires you to take a moment to reflect and appreciate the beauty of nature.