Lake Marakapia

Lake Marakapia
[mapframe not available on SimWiki] Interactive map of Lake Marakapia
Location	Chatham Island, New Zealand
Coordinates	43°50′33″S 176°33′18″W
Primary outflows	two unnamed streams
Surface area	36 ha (89 acres)
Max. depth	2.5 m (8.2 ft)

Lake Marakapia is a shallow dune lake on Chatham Island in New Zealand. Surrounded by sand dunes and livestock pasture, it has cloudy, eutrophic water, and hosts algae as well as fish such as New Zealand smelt and giant kōkopu.

Description

Lake Marakapia is a shallow dune lake on Chatham Island in New Zealand, located on the isthmus which runs between Petre Bay and Te Whanga Lagoon. It has an area of 36 hectares (89 acres), and a maximum depth of 2.5 m (8.2 ft), among the deeper lakes on the island. It is surrounded by a sandy drainage basin covered in dunes, unlike the peat-dominated basins of most other lakes on the island. The water is quite turbid, green and eutrophic. A monitoring site at the southwest shore shows notably high levels of nitrogen in the lake. Levels of phosphorus and algae in the lake are moderate but very likely increasing.

The sediment of Lake Marakapia is mainly sand, with organic matter and mud near the shore. The land surrounding the lake is used as pasture for local livestock, who are able to directly access the lake. Two outflow streams drain the lake.

Flora and fauna

The water plant Ranunculus acaulis (dune buttercup) grows as a submergent plant near the shores of the lake. Fish such as New Zealand smelt and the giant kōkopu (a vulnerable species) live in the lake. In 1949, smelt from the lake (alongside samples from nearby Lake Huro and Tennants Lake) were described as a separate species from New Zealand smelt, R. chathamensis; this was later synonymised with Retropinna retropinna, New Zealand smelt. Smelt from Lake Marakpia show genetic ties to those found in Tennants Lake, although Lake Huro seems to have a genetically distinct population. The smelt in Marakapia were noted to host the viruses Retropinna adomavirus-3 and Retropinna astrovirus-1.

In the 1930s and 1940s, Major G. F. Hutton, a property owner in the Chathams, attempted to establish a local trout population. In 1947, he had a flying boat deposit 5,000 juvenile brown trout into Lake Marakapia. As the lake (like most on Chatham Island) lacks suitable spawning habitat, the introduced trout population soon went extinct.

References

Bibliography

• Ara, Motia Gulshan (2023). Evolutionary History and Effects of Landlocking on New Zealand Smelts (PhD thesis). University of Otago.
• Bird, Eric (2010). "The Chatham Islands". In Bird, Eric (ed.). Encyclopedia of the World's Coastal Landforms. Springer Nature. pp. 1413–1422. doi:10.1007/978-1-4020-8639-7_244. ISBN 9781402086380.
• Champion, Paul D.; Clayton, John S. (March 2004). "Aquatic Vegetation of Chatham Island (Rekohu)". Department of Conservation Science Internal Series (164). Department of Conservation. ISBN 0-478-22086-3. ISSN 1175-6519.{{cite journal}}: CS1 maint: periodical has ISBN (link)
• Grimwood, Rebecca M.; Fortune-Kelly, Grace; Holmes, Edward C.; Ingram, Travis; Geoghegan, Jemma L. (2023). "Host Specificity Shapes Fish Viromes Across Lakes on an Isolated Remote Island". Virology. 587. doi:10.1016/j.virol.2023.109884. ISSN 0042-6822. PMID 37757732.
• Meredith, Adrian S.; Croucher, Robyn (2007). State of the Environment Monitoring: Water Quality and Ecosystem Health of the Lakes, Streams and Te Whanga, Chatham Island/Rekohu/Wharekauri (PDF) (Report). Chatham Islands Council. ISBN 978-0-9582920-1-6.
• Skrzynski, W. (1967). "Freshwater Fishes of the Chatham Islands". New Zealand Journal of Marine and Freshwater Research. 1 (2): 89–98. doi:10.1080/00288330.1967.9515195.