Biodiversity

 The restoration of the Jericho Valley (where Te Kōawa Tūroa o Takitimu is located) is significant as few of the original lowland ecosystems within the Takitimu Ecological District have survived intact. The natural regeneration of the site will allow these lowland ecosystems to return.

The site also forms a valuable ecological corridor from a lowland area to montane habitats in the Takitimu Mountains. Threatened and vulnerable species are present including kārearea (NZ falcon), mātātā (fernbird), kanakana (lamprey), tuna (long-finned eel), and several plant species.

While the site Te Kōawa has previously been heavily modified through land clearance and farming operations, there are areas of native vegetation with natural regeneration occurring on much of the site. Natural succession processes are underway working to return the site to a woody vegetation cover and eventually forest habitats. Appropriate management will be required to restrict the impact of the most threatening weed species and foster a diverse species range within the eventual native forest habitats. The marginal strip to the north of Redcliff Creek provides a seed source for some species. It is proposed to plant pockets of native plants to provide food and habitat for native birds, and a seed source for natural regeneration.

DOC Botanist Brian Rance visited the site in 2000 and in his botanical report stated:

“The area contains a relatively rich diversity of plant communities and species. This combined with the predominantly natural character of the area make the area of conservation importance. The strong regeneration and anticipated restoration initiatives will serve to increase the ecological values of the area…

Overall the area is a most worthwhile initiative with significant conservation values and restoration potential.”

Wetlands are a feature of the site. Naturally occurring wetland areas include natural seepages, valley-floor tussocklands, swamps and other wetland types. There is also a constructed wetland formed by a high-water diversion of Jericho Stream. Over 90% of wetlands in Southland have been lost since the mid-1800s, which makes sites like these even more important to protect and enhance.

Jericho Stream is a fast flowing, spring-fed stream that has previously been modified to deepen the channel to facilitate drainage and contain flood events. The stream holds ecological values and the site has significant natural character. In the lower reaches the riparian margins have regenerated with mānuka, pūrei/carex secta and other native species, to provide some shading and natural habitat. In the upper reaches that were recently grazed the stream margins are pasture grasses.

Not much is known about mokomoko/lizards at the site, or invertebrates, but this is something we would be keen to investigate further. There are likely to be lizard species present, but these will be under threat from introduced predators.

Manu/bird species observed at the site include kārearea/NZ falcon, kāhu/NZ swamp harrier, karoro/Southern black-back gull, mātātā/fernbird, riroriro/grey warbler, pīwakawaka/fantail, tauhou/silvereye and korimako/bellbird.

References

Rance, B. 2000. Redcliff Valley Botanical Report. Unpublished report. Department of Conservation, Southland.

Stowe, C. 2017. Ecological Assessment Report: Jericho TAKI04. Environment Southland.