Tomahawk Lagoon is a twin-lobed

lagoon A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') a ...

, located at the western end of the

Otago Peninsula The Otago Peninsula ( mi, Muaūpoko) is a long, hilly indented finger of land that forms the easternmost part of Dunedin, New Zealand. Volcanic in origin, it forms one wall of the eroded valley that now forms Otago Harbour. The peninsula lies sou ...

within the city limits of

Dunedin Dunedin ( ; mi, Ōtepoti) is the second-largest city in the South Island of New Zealand (after Christchurch), and the principal city of the Otago region. Its name comes from , the Scottish Gaelic name for Edinburgh, the capital of Scotland. Th ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. It lies close to the southeastern edge of the city's main urban area, near the suburb of Ocean Grove, which lies close to its southern shore. This suburb was also known as Tomahawk until the 1930s.

Name

The name "Tomahawk", documented in the ''Otago Witness'' from 1852, is unlikely to be a reference to the

weapon A weapon, arm or armament is any implement or device that can be used to deter, threaten, inflict physical damage, harm, or kill. Weapons are used to increase the efficacy and efficiency of activities such as hunting, crime, law enforcement, s ...

. It is more likely an anglicized form of the

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the C ...

words ''toma haka'', often interpreted as "dance by a gravesite". ''Toma'' means a place of bones, or shrine for bones; ''haka'' is here taken to mean the Māori dance of challenge, but may rather be the Southern Māori form of the word ''hanga'', to build or create. However, there are no known pre-European burial sites or reported finds of human bones in the area.

Physical geography

The lagoon, which is connected by a short stream to the

Pacific Ocean 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 ...

, is noted for its bird life. Despite its name, it is never inundated with the sea, but is more of a shallow coastal lake, predominantly under in depth. The top lagoon (inner lobe) is a wildlife reserve. Tomahawk Lagoon is separated from the sea at low tide by

Tomahawk Beach Tomahawk Beach is a beach on the Pacific Ocean southeast of the city centre of Dunedin, New Zealand. Located within the Ocean Grove Reserve between St Kilda Beach and Smaills Beach, at the point where Otago Peninsula joins the mainland of t ...

, which runs east from the Lagoon's mouth for about . A smaller beach,

Smaills Beach Smaills Beach (often spelled "Smails Beach") is a beach on the Pacific Ocean southeast of the city centre of Dunedin, New Zealand. Located within the Ocean Grove Reserve adjacent to Tomahawk Beach, at the point where Otago Peninsula joins the ...

, lies further to the east, beyond which is the outcrop of Maori Head, from the lagoon's mouth. A rocky reef and the small Bird Island lie close to the headland. To the west of the lagoon's mouth is the prominent headland of

Lawyers Head Lawyers Head (often punctuated as the more grammatically correct Lawyer's Head) is a prominent landmark on the coast of Otago, New Zealand. Located within the city of Dunedin, this rocky headland juts into the Pacific Ocean at the eastern end of th ...

, a major Dunedin landmark. The outer lobe (the Bottom Lagoon) is the larger, being some in length and wide at its widest point. It is roughly a

parallelogram In Euclidean geometry, a parallelogram is a simple (non- self-intersecting) quadrilateral with two pairs of parallel sides. The opposite or facing sides of a parallelogram are of equal length and the opposite angles of a parallelogram are of equa ...

in shape, and covers an area of close to . The Top Lagoon joins the Bottom Lagoon via a short stream in the middle of the latter's eastern shore. It is roughly triangular, being in length and in width, and covers an area of some . The total area of the lagoon is thus some . The total catchment area of the lagoon is . Several small streams flow through the steep valleys which lie to the north and northeast. The largest of these is Lagoon Creek, which flows from near

Arthur's Seat Arthur's Seat ( gd, Suidhe Artair, ) is an ancient volcano which is the main peak of the group of hills in Edinburgh, Scotland, which form most of Holyrood Park, described by Robert Louis Stevenson as "a hill for magnitude, a mountain in virtue ...

for some before feeding the Top Lagoon at its northeastern end. Owing to the

pastoral A pastoral lifestyle is that of shepherds herding livestock around open areas of land according to seasons and the changing availability of water and pasture. It lends its name to a genre of literature, art, and music (pastorale) that depicts ...

nature of much of the surrounding land, nutrient runoff into the lake is frequently high, resulting in its often

eutrophic Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytoplank ...

nature.S. F. Mitchell (1974) "Phosphate, Nitrate, and Chloride in a Eutrophic Coastal Lake in New Zealand
(abstract)

References

{{reflist Geography of Dunedin Otago Peninsula Lagoons of New Zealand Landforms of Otago Wetlands of Otago