‘Recovering’ Rookery on Miller Bay?
When the tide was out, I noticed the increased posturing and territorial displays of the Great Blue Herons lining Miller Bay. The Great Blue Heron is the largest heron in north America, standing as high as 4 feet tall, with a wing span of nearly 6 feet, they are icons of the wetlands and are often seen in the shallows foraging for food. Herons are usually solitary creatures, but when breeding season rolls around, that behavior changes dramatically.
Photo: Jennifer Duvall
This spring showcased the most heron activity we’ve seen in the 15 plus years we’ve lived on Miller Bay. We observed a ‘personal record’ of 12 herons hanging out along the shore at the same time! They defend their feeding territories from other herons with dramatic displays where they approach intruders with their heads thrown back, wings outstretched and bills pointing skyward. Gulls and even humans may be a target of this defensive maneuver. The constant chasing and guttural squawking that happens with their territorial posturing is hard to ignore.
One afternoon two herons flying with sticks caught my attention. I watched their less than robust attempt to start a nest directly across the bay from our house, in a tree that was leaning precariously over the water. Perhaps fortuitous for the future heron chick, the sticks fell through the branches and into the water and nest building efforts in that tree ceased!
All this activity made me wonder if herons were nesting in the area again, and in what can only be called a serendipitous moment, I received a text from a neighbor across the bay with a video of some heron chicks near her house! There used to be a rookery near that same area until the early 90’s when, despite the efforts of the Miller Bay Citizen’s Action Group (now known as Friends of Miller Bay—read about our history here), to protect the rookery, the subdivision ‘Heron’s Cove’ was approved, built and the herons subsequently abandoned the rookery. So, I was very intrigued…do we have a burgeoning rookery in the making?
Photos by Sheri Flynn
Herons start mating in winter or early spring — by January in the southernmost regions, usually by February or March farther north. Pairs are monogamous throughout the season, but they usually look for new mates each year with elaborate courting displays. For most of the year, great blue herons are solitary, but they almost always nest in a rookery. Rookeries, defined as a congregation of nesting birds, can include anywhere from 50 to more than 500 pairs nesting together. Though they can nest on or near the ground, great blue herons are more likely to be nesting up to 100 feet high in the treetops.
As you might expect for such large birds, they build large nests, stretching at least 20 inches across. Because herons will reuse nest sites, nests can become substantial over time, some are as long as four feet across and several feet deep. Local resident, Jennifer Duvall, said this is the first year they’ve seen heron nests being built; three nests in two trees, one nest ended-up with three chicks (no chicks were noted in the other two nests).
The female heron lays two to six pale blue eggs, over several days. Incubation takes nearly a month, with males and females taking turns sitting on the eggs. Newly-hatched heron chicks are gangly and covered in soft gray down, and they weigh about as much as a tennis ball. They have voracious appetites, and both parents are kept busy feeding them with regurgitated fish, crustaceans, frogs, or insects. After the first month, parents switch to whole fish, rodents, frogs, and more.
It takes a while for these nestlings to grow to their full size — about two and a half to three months. They begin to fledge when they’re around two months old, stretching their wings and hopping around in the nest and on branches nearby. After they build enough strength in their wing muscles, the young birds take flight and begin their lives as one of the largest water birds in North America.
Only time will tell if this is the beginning of a rookery or just a few herons setting-up camp in the neighborhood. Either way, it has been fascinating to observe the behaviors of these magnificent birds!
By Michelle Amicucci
Michelle has lived in the PNW for almost 30 years. She’s now retired and enjoying creating art, watching birds, reading, gardening and most of all, playing with her dogs. She considers her biggest gardening achievement to being able to finally attract bats to her garden, (they’ve returned the past five years!). To learn more about attracting bats to your garden, visit https://www.batcon.org/about-bats/bat-gardens/
Sources:
Cornell Lab of Ornithology, “Great Blue Heron: Life History,” “Bird Cams FAQ: Great Blue Heron Nest“
National Audubon Society, “Field Guide: Great Blue Heron“
All About Birds, “Great Blue Heron”
If you witness Distressed Wildlife...
After a recent incident where I witnessed two bald eagles attack an osprey, leaving the osprey literally stuck in the mud, and me helpless to render aid (the mud made it almost inaccessible and I was also on crutches), I reached out to Westsound Wildlife Center and asked for advice on how to assist wildlife in distress when the shelter isn’t open. (FYI- Fortunately for the osprey (and my mental health!) the rising tide allowed it to wriggle free and was last seen perched on some driftwood as darkness fell.)
Wildlife Resources:
West Sound Wildlife Shelter
9 a.m. to 4 p.m. daily
https://westsoundwildlife.org/
206-855-9057 ext. 1
There are useful tips on rescuing wildlife on the shelter’s website. For after-hours assistance, Sawyer Kibler, Education Program Manager recommends calling the Washington Dept of Fish and Wildlife. Note: If someone is able to safely capture the animal, it’s acceptable to keep it in a well-ventilated box or carrier, somewhere dark and quiet until connecting with the shelter the following morning.
Washington Department of Fish and Wildlife (WADFW)
360-902-2936 Option 1. They are one of the few resources available to help after hours.
