, 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 province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

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 (geography), gulf, sea, sound (geography), sound, or bight (geogra ...

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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 ri ...

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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 tot ...

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 states, a federal district, five major unincorporated territorie ...

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Delta Delta commonly refers to: * Delta (letter) (Δ or δ), a letter of the Greek alphabet * River delta, at a river mouth * D ( NATO phonetic alphabet: "Delta") * Delta Air Lines, US * Delta variant of SARS-CoV-2 that causes COVID-19 Delta may also ...

Surrey Surrey () is a ceremonial and non-metropolitan county in South East England, bordering Greater London to the south west. Surrey has a large rural area, and several significant urban areas which form part of the Greater London Built-up Area. ...

, White Rock , pushpin_map = British Columbia , pushpin_label_position = , pushpin_map_alt = , pushpin_map_caption = , website = , reference = Boundary Bay is a shallow

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 (geography), gulf, sea, sound (geography), sound, or bight (geogra ...

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 North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

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 North ...

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 territori ...

state of

Geography

Boundary Bay is bounded to the east by the city of Blaine in Washington and the cities White Rock and

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 subgroup. The band's main community and offices are located on the Semiahmoo Indian Reserve which is sandwiched between the boundary of White Rock, Briti ...

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

suburb A suburb (more broadly suburban area) is an area within a metropolitan area, which may include commercial and mixed-use, that is primarily a residential area. A suburb can exist either as part of a larger city/urban area or as a separate ...

) 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 ...

pene-exclave An enclave is a territory (or a small territory apart of a larger one) that is entirely surrounded by the territory of one other state or entity. Enclaves may also exist within territorial waters. ''Enclave'' is sometimes used improperly to deno ...

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 Semiahmoo Bay ( ) is the southeastern section of Boundary Bay on the Pacific coast of North America. The bay is named for the Semiahmoo First Nation, who originally occupied the area. The Semiahmoo Peninsula borders the bay and was home to canne ...

; Blaine's

Drayton Harbor Drayton may refer to: People * Drayton (surname) Legal cases * ''United States v. Drayton'', 536 U.S. 194 (2002) Places Australia *Drayton, Queensland, a locality in the Toowoomba Region *Shire of Drayton, a former local government area in Quee ...

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 The Pacific Flyway is a major north-south flyway for migratory birds in the Americas, extending from Alaska to Patagonia. Every year, migratory birds travel some or all of this distance both in spring and in fall, following food sources, heading ...

, particularly for

western sandpiper The western sandpiper (''Calidris mauri'') is a small shorebird. The genus name is from Ancient Greek ''kalidris'' or ''skalidris'', a term used by Aristotle for some grey-coloured waterside birds. The specific ''mauri'' commemorates Italian bota ...

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 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 fl ...

s, extensive

eel grass Eelgrass is a common name for several plants and may refer to: * ''Zostera'', marine eelgrass * ''Vallisneria ''Vallisneria'' (named in honor of Antonio Vallisneri) is a genus of freshwater aquatic plant, commonly called eelgrass, tape grass o ...

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 dominated ...

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 Dunlins and Red knots">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 mudflat ...

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.

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 airpo ...

, 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