Post Point Heron Colony: A History of Community Conservation
Author: Analiese Burns, MA, PWS. Analiese Burns serves as the Habitat and Restoration Manager for the City of Bellingham Public Works Department – Natural Resources Division
Spring is a busy time at the Post Point Heron Colony. This year we welcome the herons’ return for their 24th nesting season – and celebrate the one year anniversary of a new conservation easement on the Post Point property.
As in past years, great blue heron (Ardea herodias) adults began gathering near the Post Point Lagoon in south Bellingham in mid-winter, getting ready for the long nesting season ahead. Although the timing of their return varies slightly from year-to-year based on weather and other factors, their nesting rituals are ancient and have been a part of the Post Point habitat since herons established the colony in 2000.
The Post Point Heron Colony is located on a City-owned forest patch in south Bellingham, adjacent to the Post Point Lagoon south of Harris Avenue. Great blue herons have long used the young forest patch to rest or preen, but the first nest wasn’t observed until 1999. In 2000 there were six active nests, establishing the site as a colony. Based on an early assessment by Nakheeta Northwest Wildlife Services, the herons likely relocated from an abandoned Chuckanut Bay colony west of Chuckanut Drive.
Since the colony’s establishment, the City of Bellingham has recognized it as a unique habitat and taken a variety of stewardship measures. The City commissioned a management plan for the colony in 2003 and in 2004 the City Council adopted a resolution to commit to continuing conservation and protection measures for the heron colony on the City’s Post Point property. The City also funded a 2005 scientific baseline study, 2019 updated management recommendations, and annual monitoring since 2005.
Annual monitoring has documented the nesting sequence and nuances specific to the Post Point Heron Colony. Herons occupy a variety of habitats in and around the colony from January to early September. In January and early February, adult herons gather in roosting habitats (forest and structures) near Post Point Lagoon. In February, adults reoccupy old nests or occasionally build new ones within the nesting area called the colony nucleus. Typically egg laying begins in March or early April. Most herons lay a single clutch, but some will stay in the colony to lay a second. Young herons hatch after approximately 28 days of incubation, beginning an especially sensitive eight weeks as adult herons search for food in grass fields and intertidal foraging habitats. Post Point adults heavily forage in the nearby Post Point Lagoon and the marine shoreline from Marine Park south. They also travel up to 11 miles round-trip to feed their growing young from marine shorelines along the Nooksack Delta, Portage Bay, and Chuckanut Bay.
During the entire nesting season, the herons are vulnerable to weather, human disturbance, and bald eagle intrusions. The forest “buffer” around the colony nucleus acts as an important wind break and protection from surrounding disturbances. The Post Point Heron Colony Management Recommendations Update (Nahkeeta Northwest Wildlife Services, 2019) recommends a 300-foot vegetation retention and no-disturbance buffer. Most of this 300-foot buffer is public land, with the exception of the residential neighborhood to the south. In 2022, the City increased protection to the south by purchasing 1.72 acres of colony buffer along Shorewood Drive. Funding was provided by the City and Whatcom Land Trust. To provide additional protection, the City granted Whatcom Land Trust a conservation easement over the 1.72 acres. As the easement holder, the Whatcom Land Trust shares the responsibility of preserving and protecting the Post Point Heron Colony in coordination with the City, including avoiding impacts to the herons or their habitats.
The nesting season ends when all the young have left the nests, or fledged. Typically, fledging begins in July and is complete as late as September 15. The colony has seen relatively steady growth since 2000. In 2022, the colony expanded to 46 successful nests, the highest number since the colony’s inception. The 2023 nesting season is just unfolding and we can all do our part to support its success.
You can help the continued success of the Post Point Heron Colony by staying on designated trails. From January to September, you can support the colony by avoiding entering the beach area south of Marine Park; maintaining quiet on trails, in parks, and other surrounding areas; and avoiding drone use near the colony. Learn more about the Post Point Heron Colony by visiting www.cob.org/herons.