The distribution of the Nationally Threatened Trithuria inconspicua subsp. inconspicua in the Kai Iwi Lakes
- Author
- Champion P, Ford M
- Year
- 2024
- Journal / Source
- Report prepared for Kauri Coast District Office, Department of Conservation, Dargaville
- Pages
- 26 pp
- Keywords
- Lake Kai Iwi, Kai Iwi Lakes, Lake Waikare, Lake Taharoa, Cyclone Gabrielle
- Summary
- Trithuria inconspicua subsp. inconspicua is a Northland endemic species, restricted to seven Northland lakes, with three being Lakes Kai Iwi, Waikare and Taharoa. This species is common in Lake Kai Iwi, occupying over a kilometre of lake shore with the total area of habitat supporting plants of Trithuria inconspicua assessed as 0.25 ha. The total area of occupancy of Trithuria inconspicua in the lake was between 95 and 250 m2 , with a total population size between 207,500 and 752,500 mature individuals. Much lower populations were found in Lake Waikare, occupying 450 m2 of shoreline. The total area of occupancy was estimated at 30 m2, with a total population size 27,500 and 55,000 mature individuals. The water level in this lake was 0.74 m lower than normal, meaning that there was limited Trithuria inconspicua habitat available at the time of survey. No Trithuria plants were seen in Lake Taharoa, it was last reported there in 2014.