A Guide to the Herons, Egrets, and Bitterns of Northwest NA

My guide to the herons, egrets, and bitterns of the Northwest Region of North America provides a comprehensive look into this group of wading birds. It features detailed species accounts with information on identification, habitat, range, behavior, food, nesting, breeding, lifespan, population status, conservation concerns, and audio recordings of their calls. The accounts are accompanied by custom-made identification plates, making it a valuable resource. In this guide, the Northwest Region of North America encompasses the states of: Washington, Idaho, Montana, Oregon, Wyoming, Alaska, and the Canadian provinces of British Columbia, and Alberta.

Species of Herons, Egrets, and Bitterns in this Guide

• Great Blue Heron (Ardea herodias): Largest North American heron; heavy bill, vocal. Includes a white morph.
• Great Egret (Ardea alba): Slender, very long neck, yellow bill.
• Snowy Egret (Egretta thula): Small, slender; black bill, yellow face, black legs, bright yellow feet.
• Cattle Egret (Bubulcus ibis): Smallest white egret; short neck; often near livestock in highlands.
• Green Heron (Butorides virescens): Small, stocky; dark plumage, pointy bill, crouches near water.
• American Bittern (Botaurus lentiginosus): Large, secretive; cryptic plumage, long neck, pointed bill.
• Black-crowned Night-Heron (Nycticorax nycticorax): Stocky, short neck, nocturnal; thick bill, mainly eats fish.

Herons, Egrets and Bitterns not found in the Northwest Region

The following species are not known to occur in the Northwest Region. However, they have been reported as vagrant individuals throughout the region. These include:

• Tricolored Heron (Egretta tricolor): Slender, long-necked; very long, slender bill; white belly, dark upperparts.
• Little Blue Heron (Egretta caerulea): Slender; faint bicolored bill; white juvenile plumage, piebald subadult.
• Reddish Egret (Egretta rufescens): Large, slender; bicolored bill, dark and white morphs, forages in shallow saltwater.
• Least Bittern (Ixobrychus exilis): Tiny, secretive; buffy and black plumage, moves in dense vegetation.
• Yellow-crowned Night-Heron (Nyctanassa violacea): Slender, longer neck, nocturnal; stout black bill, feeds on crabs.

If a heron observed in the Northwest Region is not found in this guide it may be that it is a vagrant individual. Please visit my Guide to the Herons, Egrets, and Bittern of the Southeast Region of North America, which lists all species known to occur in North America.

Note: Many people find it tricky to tell the white herons and egrets apart. For help with identification, see my guide: North American White Egrets and Herons: An Identification Guide

Herons and Egrets: Understanding the Difference

The distinction between “heron” and “egret” is primarily based on traditional naming conventions and visual appearance, particularly plumage color, rather than strict biological classifications. There is no particular set of characters that differentiates one group from the other.

Traditional Naming Conventions:

Historically, the term “egret” has been used to describe members of the Ardeidae family that typically have white plumage, especially those that develop long, decorative plumes during breeding season, such as the Great Egret and Snowy Egret. In contrast, “heron” is often used for the larger, non-white members of the family.

Taxonomic Reality:

From a taxonomic perspective, both herons and egrets belong to the Ardeidae family. Therefore, egrets are, technically, a type of heron, and vice versa. There is no clear-cut scientific division that definitively separates all “herons” from all “egrets.” In fact, the Great Egret (a purely white-plumaged bird) is taxonomically more closely related to the Great Blue Heron than it is to other white-plumaged egrets.

Exceptions to the Rule:

However, this is not a strict rule, and there are many exceptions. For example:

• The Little Blue Heron is white only as a juvenile, transitioning to a dark gray-blue as an adult.
• The Reddish Egret exhibits both a white color morph and a dark color morph.
• The Great Blue Heron also has a white color morph, as well as individuals with intermediate plumage.

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The 7 species of herons, egrets, and bitterns that occur in the Northwest Region

Great Blue Heron

Identification: Largest North American heron with long legs, sinuous neck, and dagger-like bill. Blue-gray plumage with a black stripe over the eye. Head, chest, and wing plumes give a shaggy appearance. White morph individuals are restricted to the Florida keys.
Habitat: Freshwater and saltwater habitats such as marshes, grasslands, isolated swamps, lakes, and ponds bordered by forests. They also forage in meadows and farmland.
Range: The Great Blue Heron is a year-round resident along the coastal region of southern Alaska, British Columbia, Washington State, and all of Oregon. It also resides year-round in the lower areas of Washington State, Idaho, Wyoming, and Montana. In the eastern half of Montana, Wyoming, Idaho, and the Province of Alberta, however, the Great Blue Heron is primarily a breeding visitor. Across all states and provinces of the Northwest Region, the species can be found as a non-breeding visitor.
Migration: The Great-blue Heron migrates to Quebec and Ontario Provinces during the month of mid May-mid July and migrates south during the Fall and Winter months mid July through December.
Behavior: They wade slowly or stand still, stalking prey in shallow water or open fields. In flight, the neck is tucked in, and legs trail behind. They defend feeding territories with dramatic displays.
Diet: Fish, amphibians, reptiles, small mammals, insects, and other birds. They grab smaller prey or impale larger fish with their bills. 
Nest: A simple platform made of small sticks in trees. They can also nest on the ground, bushes, mangroves, and structures usually in mixed-species colonies of  500 or more nests.
Breeding: Breeding months: Mid March-Mid August | Clutch Size: 2-6 eggs | Number of Broods: 1-2 | Egg color: Pale blue | Incubation Period: 27-29 days | Nestling Period: 49-81 days.
Lifespan: The Great Blue Heron lives at least 24 years and 6 months.
How many are there?: The global breeding population is estimated to be 700,000.
Conservation: Great Blue Heron numbers are stable and increased in the U.S. between 1966 and 2019. They are of low conservation concern.

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Great Egret

Identification: Tall, long black legs, all white plumage with an S-curved neck and yellow bill. Smaller than a Great Blue Heron, larger than a Snowy Egret. It grows long plumes from its back during the breeding season.
Habitat: Freshwater, brackish, and marine wetlands.
Range: The Great Egret is a breeding visitor (May-September) in parts of Oregon, Wyoming, Idaho, and perhaps Washington State. Although have be present throughout the region, it is not known to regularly occur in Alaska, and the Canadian provinces of British Columbia and Alberta.
Migration: Great Egrets migrate north to the breeding grounds visiting northern states between mid May through September. From October to mid May they migrate south to warmer latitudes.
Behavior: Wades in shallow water to hunt, typically standing still and watching for prey, then strikes with a jab of its neck and bill. 
Diet: Mainly small fish, but also amphibians, reptiles, birds, small mammals, and invertebrates.
Nest: A platform made of sticks and twigs, up to 3 feet across in or near the top of a shrub or tree. Breeds in colonies with other egrets and herons.
Breeding: Breeding months: Late March-July | Clutch Size: 1-6 eggs, Number of Broods/year: 1-2. | Egg Description: Pale greenish-blue | Incubation Period: 23-27 days | Nestling Period: 21-25 days.
Lifespan: The oldest known Great Egret was 22 years, 10 months old.
How many are there?: Approximately 9.5 million breeding birds on the continent.
Conservation: The Great Egret is considered a species of low concern. Populations are increasing.  

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Snowy Egret

Identification: All white with a black bill, black legs, and yellow feet. Immatures are similar with duller, greenish legs. During the breeding season, they grow filmy, curving plumes.
Habitat: They can be found in all types of fresh, salt and brackish water wetlands. 
Range: The Snowy Egret is a breeding visitor from mid-May through July to selected areas in southern Idaho and Wyoming. It occurs as a nonbreeding visitor in Southeast Oregon, part of Idaho, and Wyoming. It is not known to regularly occur further north.      
Migration: Snowy egrets migrate north during the Spring and Summer months but return to the south, usually to coastal areas, during the Fall and Winter months.
Behavior: Wades in shallow water to spear fish. They may run back and forth chasing their prey or use their bright yellow feet to paddle in the water or probe in the mud, rounding up prey before striking with their bill.
Diet: Mostly small fish and other animals, including frogs, worms, crustaceans, and insects.
Nest: A shallow, loosely woven platform of twigs 14–18 inches across. The nest is usually over water in the top or outer branches of shrubs or trees.
Breeding: Breeding months: Mid March- July | Clutch Size: 2-6 eggs | Egg color: Pale greenish blue | Incubation Period: 24-25 days | Nestling Period: 20-24 days.
Lifespan: The Snowy Egret lives for at least 17 years, 7 months.
How many are there?: Partners in Flight estimates the global breeding population at 2.1 million.
Conservation: The Snowy Egret is a bird of low conservation concern. Their biggest continuing threat is habitat loss.

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Cattle Egret

Identification: A stocky heron with a short thick neck. Adults are white with buff plumes during breeding season. The bill is yellow turning bright red before pairing. Juveniles lack colored plumes and have a black bill. 
Habitat: Inundated grasslands, pastures, farmlands, wetlands, and rice paddies. They exploit drier, open areas more than other heron species.
Range: In the Northwest Region of North America, the Western Cattle Egret is mostly a non-breeding visitor to southern Oregon, Idaho, and Wyoming. It may breed in selected locations in these states. It is not known to regularly venture further north to Washington State, and the Canadian provinces of British Columbia and Alberta.
Migration: Cattle Egrets expand their range throughout the Northwest Region in the months of mid March through November but migrate south and it is absent from the region from mid December through March.
Behavior: Often accompany cattle, catching insects and small vertebrates disturbed by these animals. They have a distinctive head-pumping strut. 
Diet: Primarily insects like grasshoppers, crickets, flies and any other invertebrate. They may also eat eggs and chicks of small birds.
Nest: A platform of sticks in trees or shrubs in swamps or reed vegetation in marshes. It breeds in colonies with other wading birds. 
Breeding: Breeding Months: March-June | Clutch Size: 3-4 eggs | Number of Broods: 1 | Egg Appearance: Pale bluish-white | Incubation Period: 23 days | Nestling Period: 30 days.
Lifespan: Can reach a longevity of 15 years.
How many are there?: Estimated global population is 3.8–6.7 million individuals.
Conservation: Considered a species of Least Concern by the IUCN.

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Green Heron

Identification: The Green Heron has a velvet-green back, rich chestnut body, and a dark cap. Juveniles are browner, with pale streaking on the neck and spots on the wings.
Habitat: Swamps, marshes, lakes, ponds, impoundments, and other wet habitats with trees and shrubs.
Range: The Green Heron is a breeding visitor (March through mid-November) along the coastal region of Oregon, Washington State, and extreme southern British Columbia. It is not known to regularly occur in the rest of the Northwest Region.
Migration: Green Herons migrate north into the Northwest Region in mid March through mid November and return to the south for the rest of the year.
Behavior: Green Herons hunt by standing still at the water’s edge, in vegetation, or by walking slowly in shallow water. When a fish approaches, the heron lunges forward and strikes with its head. 
Diet: Mainly small fish. They also feed on insects, spiders, crustaceans, snails, amphibians, reptiles, and rodents.
Nest: A simple platform made of sticks 8–12 inches across. Pairs choose a secluded site within their territory, usually in a tree or bush with overhanging branches to conceal the nest. 
Breeding: Breeding months: Mid February-mid July | Clutch Size: 3-5 eggs | Number of Broods: 1-2 broods | Incubation Period: 19-21 days | Egg color: Pale green to bluish | Nestling Period: 16-17 days.
Lifespan: The Green Heron lives at least 8 years, 11 months old.
How many are there?: Partners in Flight estimates the global breeding population at 1.2 million.
Conservation: Although Green Herons are fairly common, their population has suffered a decline of about 51%. Green Heron is included on the list of Common Birds in Steep Decline.

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American Bittern

Identification: Medium-sized heron with a compact body, shorter legs, and a thick neck. Warm brown and buff with strong streaks. When alarmed, it points its bill straight up to blend with reeds. 
Habitat: Shallow freshwater marshes with reeds and vegetation, typically near the margins. 
Range: The American Bittern is a year-round resident along the coastal region of Oregon and the southern half of Washington State. It breeds (mid-June through mid-August) throughout the Northwest Region, without reaching Alaska.
Migration: The American Bittern is a highly migratory bird commuting between the breeding grounds in the Northwest Region and the non-breeding and year-round grounds in the Southwest and further.
Diet: Insects, crustaceans, fish, amphibians, reptiles, and small mammals and large insects. 
Nest: A mound or platform built among thick stands of cattails, bulrushes on shallow water or on dry ground. The nest is made of dead, dry reeds, sedges, or other vegetation and lined with fine grasses.
Breeding: Breeding months: April-August | Clutch Size: 2-7 eggs | Incubation Period: 24-28 days | Nestling Period: 7-14 days (chicks linger around nest for weeks) | Egg color: Beige-brown to olive.
Lifespan: The American Bittern lives at least 8 years and 4 months.
How many are there?: The global breeding population is estimated at 2.5 million.
Conservation: Considered a species of relatively low conservation concern, but their numbers have declined in some regions.

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Black-crowned Night-Heron

Identification: Adults have light-gray plumage with a black back and crown. Immatures are brown with white spots and blurry streaks. Adults have all-black bills, while immatures have yellow-and-black bills.
Habitat:  Saltmarshes, freshwater and brackish water wetlands of all types. They require aquatic habitat for foraging and terrestrial vegetation for cover.
Range: The Black-crowned Night-Heron is a year-round resident only in southwest Oregon. It is a breeding visitor in Washington State, about half of Idaho, parts of Montana and Wyoming. It is also a breeding visitor to part of the Canadian province of Alberta.
Migration: It expands throughout the region during the Spring and Summer months but migrates to the south and selected regions in Western USA during the fall and winter months.
Behavior: Most active at night or at dusk. They spend their days perched on tree limbs or concealed among foliage and branches.
Diet: They are opportunistic feeders eating many kinds of terrestrial, freshwater, and marine animals. They also eat carrion, plant materials, and garbage from landfills.
Nest: It nests in a tree or in cattails; a platform of sticks and other woody vegetation. Black-crowned Night Herons nest colonially, sometimes with a dozen nests in a single tree.
Breeding: Clutch Size: 3-5 eggs | Egg appearance: Greenish-blue | Incubation Period: 24-26 days | Nestling Period: 29-34 days.
Lifespan: The Black-crowned Night Heron lives at least 21 years, 5 months.
How many are there?: Partners in Flight estimates a global breeding population of 3 million.
Conservation: The Black-crowned Night Herons is a species of low conservation concern. 

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Habitats of Herons, Egrets, and Bitterns

In the Northwest Region of North America, Herons, egrets, and bitterns use an array of aquatic habitats. The presence of shallow water and an abundance of small fish, amphibians, and crustaceans are the most important factors for observing these birds.

These habitats include:  

Estuaries: Where freshwater rivers meet the saltwater of the ocean, creating brackish environments. These are highly productive areas, providing abundant food sources. Expect to see a high diversity of egrets and herons, particularly during low tide when foraging is optimal.

Wetlands: Including salt marshes, freshwater marshes, swamps, and pocosins. These areas are vital for filtering water, preventing floods, and providing habitat. These areas attract species that prefer freshwater prey, such as the American Bittern and Green Herons.

Rivers: From slow-moving coastal rivers to faster-flowing Piedmont and mountain rivers. Riverbanks and floodplains offer foraging and nesting sites. Look for herons along riverbanks and in shallow areas, especially during early morning and late evening.

Lakes, Lagoons, and Reservoirs: Including natural lakes and man-made reservoirs that provide open water and shoreline habitats. Look for herons along riverbanks and in shallow areas, especially during early morning and late evening.

Coastal versus Inland Habitats

The coastal habitats: The mix of saltwater and freshwater is particularly productive for these wading birds. Estuaries, where rivers meet the ocean, offer abundant food sources like fish, crabs, and shrimp. Salt marshes, with their shallow waters and dense vegetation, provide ideal foraging and nesting sites.

Inland habitats: While the coast boasts a high concentration of these birds, inland areas also offer valuable habitats. Freshwater lakes, rivers, and wetlands provide essential foraging and nesting sites.

Where to find Herons, Egrets, and Bitterns in the Northwest Region

This section guides you to prime locations in Washington, Oregon, and British Columbia for observing herons, egrets, and bitterns. We’ve highlighted conservation areas with essential wetland and aquatic habitats. For each region, find a recommended coastal and an inland site, complete with their status, to help you plan your birdwatching excursions.

Where to Find Herons, Egrets, and Bitterns

Here are some key conservation areas in the subject states and province that offer suitable habitats for herons, egrets, and bitterns:

Washington

• Coastal:
• Padilla Bay National Estuarine Research Reserve ( National Estuarine Research Reserve (managed by the Washington State Department of Ecology)
• Inland:
• Columbia National Wildlife Refuge (managed by the U.S. Fish and Wildlife Service)

Oregon

• Coastal:
• Oregon Islands National Wildlife Refuge (includes accessible units like Nestucca Bay and Bandon Marsh) (managed by the U.S. Fish and Wildlife Service)
• Inland:
• Malheur National Wildlife Refuge (managed by the U.S. Fish and Wildlife Service)

British Columbia

• Coastal:
• George C. Reifel Migratory Bird Sanctuary (managed by Environment and Climate Change Canada)

• Inland:
• Vaseux-Bighorn National Wildlife Area (managed by Environment and Climate Change Canada)

Land-locked States and Province

This section focuses on finding herons, egrets, and bitterns in the inland regions of Idaho, Montana, Wyoming, and the Canadian province of Alberta. These areas feature vital wetland, riparian, and lake habitats. Below are recommended conservation areas in each location, including their names and management statuses, to assist you in planning your search.

Idaho

• Camas National Wildlife Refuge (managed by the U.S. Fish and Wildlife Service)
• Hagerman Wildlife Management Area (managed by Idaho Fish and Game)

Montana

• Lee Metcalf National Wildlife Refuge (managed by the U.S. Fish and Wildlife Service)
• Bowdoin National Wildlife Refuge (managed by the U.S. Fish and Wildlife Service)

Wyoming

• Cokeville Meadows National Wildlife Refuge (managed by the U.S. Fish and Wildlife Service)
• Hutton Lake National Wildlife Refuge (managed by the U.S. Fish and Wildlife Service)

Alberta

• Frank Lake Conservation Area (managed in partnership, including Ducks Unlimited Canada)
• Lois Hole Centennial Provincial Park / Big Lake (managed by Alberta Parks)

Final Remarks:

The Northwest Region of North America offers a diverse types of habitats for herons, egrets, and bitterns along the Atlantic Coast. While some species breed in parts of the region, most are widespread as Spring and Summer season visitors migrating south during the cold month of Fall and Winter. This guide examines the seven species found in this region encompassing the states of: Washington, Idaho, Montana, Oregon, Wyoming, Alaska, and the Canadian provinces of British Columbia, and Alberta. I hope this guide enhances your appreciation for the herons, egrets, and bitterns of the Northwest Region.

Photo Credits:

The photographic material used in this guide was made available on various websites. Many thanks to Andrew Morffew, Mark Mochell, Elizabeth Milson, Duzan Brinkhuizen, Matt Weller, Troy Anderson, Dennis Church, Wendy Miller, Rick From Alabama, Carlos Sanchez, John Benson, Mick Thompson, Steve Guttman, Victor Espinoza, Kelly Colgan-Azar, Andy Reago, Chrissy McLaren, Garry C., Michael Janke, Cuatro77, Linda Fortuna, Vicky DeLoach, Paul Hurtado, Tom Murray, Tom Wilberding, Patricia Pierce, Kenneth Cole-Schneider, Doug Greenberg, Brian Garrett, David White, Victoria Pickering, Becky Matsubara, Dan Mooney, and Julio Mulero.

Voices:

Most recordings were made by Paul Marvin (Xeno-canto https://xeno-canto.org/contributor/RFTXRYBVBX)

References and Sources:

• eBird. (https://ebird.org/)
• Sibley, David, 2000, The Sibley Guide to Birds.
• Species Longevity Data: United States Geological Survey (https://www.usgs.gov/)
• Allaboutbirds