Stanley Park is home to one of the largest urban great blue heron (Ardea herodias fannini) colonies in North America. They have been nesting at their current location behind 2099 Beach Avenue since 2001 and have been documented nesting in various other locations in Stanley Park as far back as 1921. Today, sightings of these majestic birds in and around the park are common place.
Unfortunately, this is not the case everywhere and these birds are classified as a species at risk in BC. This subspecies of heron does not migrate. As they have difficulty finding undisturbed habitat and nesting sites, their population has declined across the province. Some colonies, including the Stanley Park heronry, have become accustomed to the presence of humans, but this is rare as human disturbance commonly causes birds to abandon their nesting areas. Raccoons, owls and bald eagles are natural predators of the eggs and young.
The Stanley Park Ecology Society has been monitoring the heronry in Stanley Park since 2004 and has worked with the Vancouver Park Board and the Canadian Wildlife Service to support herons in their urban environment. The creation of a Stanley Park great blue heron management plan was a giant step towards the successful management of this species.
Identifying Breeding Adults
Breeding adults have ornate plumes on their heads, necks and backs while non-breeding adults and juveniles don’t have these features. Juveniles have a distinctly larger black crown on their heads. Males are slightly larger than females and have longer bills, but they are extremely hard to tell apart.
Heron Nesting Calendar
Mid-February – Mid-March
Males return to the colony and begin courting females by stretching their necks vertically and emitting loud cries. Courting couples will cross their bills. Together they occupy existing nests or build new ones, improving and maintaining their nest together.
March – April
Eggs are laid 1-2 days apart and after a 28-day incubation period the 3 to 7 eggs begin to hatch. Both adults feed the young by regurgitating directly into the chicks’ open beaks. Weaker chicks often starve due to sibling dominance or may be pushed out of the nest by siblings.
May – June
At 6 weeks of age, the young are still fed in the nest but they begin walking along nearby branches. Two weeks later, they begin their first clumsy flights between branches and nearby trees.
July – August
At 10 weeks of age, the young leave the nests and follow their parents to feeding grounds where they learn to hunt for fish, frogs and voles, beginning the process of independent life.
For more details, please read the Stanley Park Heron Colony 2012 final report
To support our programs, please consider Adopting a Nest