Black Swamp

Description: A cushion-plant bog with large peat dome, wire rush (Empodisma minus), sedges, herbs and scrubs. 1

Type/Class: Swamp. 2

Size: 5.9 ha.

Altitude: 380-400 m above sea level.

Approximate location: 2.4 km Northwest of intersection of Black Swamp Road and Fleets Road, Milton |  NZTM (centre point): E1359810 N4901170.

Regional Plan: Water for Otago | Schedule 9 Regionally Significant Wetland, no.10, Map F31.

Territorial Authority: Clutha District Council.

Recorded Values

Value Description
A4 High degree of wetland naturalness. Vegetation is mainly wire rush (Empodisma minus) and Sphagnum sp., with Manuka and Dracophyllum sp., plus rushes and sedges in surrounding lags. 2, 5
A5 Scarce in Otago in terms of its ecological or physical character. Scarce wetland type: very little of this type of wetland left in the Otago Region. 1 Less than 15% of swamps remain in Otago. 2
A1-A3, A6-A9 No relevant information is currently held by the ORC.

Other Information

  • Presence of Fernbird (Bowdleria punctata). 5
  • Black Swamp is a cushion bog. Cushion bogs are a distinctive feature of the moist cloudy uplands of the south-eastern South Island, but few examples actually remain despite their national or international significance. 95
  • A diversity of plant species is present, with several different plant communities. There are a few weed species present found only at the margins. 5
  • The Black Swamp Conservation Area, administered by the Department of Conservation, covers part of the swamp. 1
  • Wire rush (Empodisma minus) is rare in East Otago and only found at Black Swamp and in the Glendhu catchment. 6
  • Other plant species found within Black Swamp include bog mingimingi (Cyathodes empetrifolia), Pernettya macrostigma, Pentachondra pumila, Olearia virgata var. rugosa, Hebe odora, Cassinia vauvilliersii, C. sp. aff. parviflora, Coprosma intertexta, creeping bent (Agrostis stolonifera), bush flax (Astelia nervosa), swamp kiokio (Blechnum minus), water fern (Blechnum penna-marina, cutty grass (Carex coriacea), star sedge (Carex echinata), Carex sinclairii, mountain daisy (Celmisia gracilenta), red tussock (Chionochloa rubra), creeping everlasting daisy (Helichrysum filicaule), grass lily (Herpolirion novae-zelandiae), holy grass (Hierochloe redolens), flatweed (Hypochaeris radicata), jointed rush (Juncus articulatus), leafless rush (Juncus gregiflorus), common rush (Juncus effuses), square sedge (Lepidosperma austral), Nertera scapanioides, Oreobolus strictus, waoriki (Ranunculus glabrifolius) and Thelymitra sp. 5

 

Aerial View of Black Swamp (March 2006)

 

References

1 Otago Regional Council (2004) Regional Plan: Water for Otago. Published by the Otago Regional Council, Dunedin.

2 Ausseil, A.G., Newsome, P., Johnson, P. (2008) Wetland Mapping in the Otago Region. Landcare Research Contract Report prepared for the Otago Regional Council.

5 Johnson, P. N. (1985) Black Swamp: Botanical Report. Botany Division, D.S.I.R., Dunedin.

6 Walker, S., et al. (2001) A Chionochloa/Sphagnum/cushion valley bog in East Otago, New Zealand. In: New Zealand Journal of Ecology, Vol. 25, no. 1, pp. 39–52.

95 Stephenson, G.K., Card, B., et al. (1983) Wetland: A Diminishing Resource (A Report for the Environmental Council. Water and Soil Miscellaneous Publication No.58. Published by the Ministry of Works and Development - Water and Soil Division, Wellington.