, image = Boundary Bay Regional Park in Tsawwassen.jpg , image_size = 260px , alt = , caption = Looking east across Boundary Bay from

Tsawwassen Tsawwassen ( ) is a suburban, mostly residential community on a peninsula in the southwestern corner of the City of Delta in British Columbia, Canada. It provides the only road access to the American territory on the southern tip of the peninsul ...

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British Columbia British Columbia (commonly abbreviated as BC) is the westernmost Provinces and territories of Canada, province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include ...

and

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

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Bay A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a gulf, sea, sound, or bight. A cove is a small, circular bay with a nar ...

, etymology = , part_of =

Salish Sea , image = PNW-straits.jpg , alt = , caption = The Salish Sea, showing the open Pacific Ocean at lower left, and from there, heading inland: the Strait of Juan de Fuca, the narrow Puget Sound at lower r ...

, inflow = , rivers = , outflow = , oceans = , catchment = , basin_countries =

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tota ...

and

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

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bay A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a gulf, sea, sound, or bight. A cove is a small, circular bay with a nar ...

situated on the

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

coast of North America on the

Canada–United States border The border between Canada and the United States is the longest international border in the world. The terrestrial boundary (including boundaries in the Great Lakes, Atlantic, and Pacific coasts) is long. The land border has two sections: Can ...

between the

Canadian province Within the geographical areas of Canada, the ten provinces and three territories are sub-national administrative divisions under the jurisdiction of the Canadian Constitution. In the 1867 Canadian Confederation, three provinces of British Nort ...

and the

U.S. The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territor ...

state of

Geography

Boundary Bay is bounded to the east by the city of Blaine in Washington and the cities White Rock and Surrey in British Columbia. It is also bounded to the east by the reserves of the

Semiahmoo First Nation Semiahmoo First Nation ( ) is the band government of the Semiahmoo people, a Coast Salish peoples, Coast Salish subgroup. The band's main community and offices are located on the Semiahmoo Indian Reserve which is sandwiched between the boundar ...

in British Columbia. To the north, it is bounded by the City of Delta. To the west, it is bounded by the Tsawwassen Peninsula, which contains the communities of

(a suburb of Delta) and

Point Roberts, Washington Point Roberts is a pene-exclave of Washington on the southernmost tip of the Tsawwassen peninsula, south of Vancouver, Canada. The area, which had a population of 1,191 at the 2020 census, is reached by land from the rest of the United States by ...

(a pene-exclave of the

). To the south, it is bounded by the

Strait of Georgia The Strait of Georgia (french: Détroit de Géorgie) or the Georgia Strait is an arm of the Salish Sea between Vancouver Island and the extreme southwestern mainland coast of British Columbia, Canada and the extreme northwestern mainland coast ...

, the northern arm of the larger

. The eastern section of Boundary Bay straddling the US/Canada border and adjacent to the cities of White Rock and Blaine is known as Semiahmoo Bay; Blaine's Drayton Harbor opens into it. The northern tip of Boundary Bay is known as Mud Bay.

Inflows

The main rivers flowing into the bay are the Nicomekl and Serpentine Rivers falling into Mud Bay, the Campbell River falling into Semiahmoo Bay, and California Creek and Dakota Creek falling into Drayton Harbor.

Ecology

It is an important stop for birds migrating along the Pacific Flyway, particularly for western sandpiper and

dunlin The dunlin (''Calidris alpina'') is a small wader, formerly sometimes separated with the other "stints" in the genus ''Erolia''. The English name is a dialect form of "dunling", first recorded in 1531–1532. It derives from ''dun'', "dull brown ...

, and has been designated a Hemisphere Reserve by the

Western Hemisphere Shorebird Reserve Network The Western Hemisphere Shorebird Reserve Network (WHSRN) is a conservation strategy targeting shorebirds in the Americas launched in 1985. Its aim is to protect the nesting, breeding and staging habitats of migratory shorebirds. The first site t ...

and a Canadian

Important Bird Area An Important Bird and Biodiversity Area (IBA) is an area identified using an internationally agreed set of criteria as being globally important for the conservation of bird populations. IBA was developed and sites are identified by BirdLife Int ...

. The

mudflat Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal f ...

s, extensive eel grass beds and

salt marsh A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is domin ...

es support a rich population of marine

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s which are an important source of energy for migrating

shorebird 245px, A flock of Red_knot.html" ;"title="Dunlins and Red knot">Dunlins and Red knots Waders or shorebirds are birds of the order Charadriiformes commonly found wikt:wade#Etymology 1, wading along shorelines and mudflats in order to foraging, ...

s. During migration times the bird count in the bay may exceed 100,000

Pollution and industrial activity in the area pose potential threats to wildlife.

Conservation

On June 21, 1995, the entire Canadian portion of Boundary Bay was protected within the

Boundary Bay Wildlife Management Area Boundary Bay Wildlife Management Area is a wildlife management area encompassing the entire Canadian portion of Boundary Bay in the Lower Mainland of British Columbia. It was established by the British Columbia Ministry of Forests, Lands, Natura ...

Activities

The area is also used for recreational boating and includes park area and beaches. The

Boundary Bay Airport Boundary Bay Airport or Vancouver/Boundary Bay Airport is located beside Boundary Bay and east of Ladner in Delta, British Columbia, Canada, south southeast of Vancouver and close to the Point Roberts-Boundary Bay border crossing. The air ...

, on its north flank, is used by small aircraft and has been the setting for various film shoots.

References

External links

Birds on the BayFilm footage of Centennial Beach in 1958A Nature Guide to Boundary Bay
Author's Site.

Photographer's Site. {{British Columbia hydrography Bays of British Columbia Bays of Washington (state) Landforms of Lower Mainland Bodies of water of Whatcom County, Washington Delta, British Columbia Surrey, British Columbia White Rock, British Columbia Important Bird Areas of British Columbia