Study

Reduction of wapiti Cervus elaphus nelsonii and red deer C.e.scoticus numbers allows recovery of native alpine grassland in Fiordland National Park, Southland, New Zealand

  • Published source details Rose A. & Platt K.H. (1987) Recovery of Northern Fiordland alpine grassland after reduction in the deer population. New Zealand Journal of Ecology, 10, 23-33

Summary

Until European settlement, New Zealand alpine grasslands were grazed only by native birds and invertebrates. In the uplands of Fiordland (South Island) by the 1930s, wapiti Cervus elaphus nelsonii and red deer C.e.scoticus (and their hybrids) introduced for hunting, were well established. By the late1960s, high deer numbers had strongly modified alpine grasslands. The effect of reducing deer numbers, mainly by aerial hunting by helicopter (and also live-capture removal) on vegetation was assessed in Fiordland National Park, Southland.

The study grasslands (c.900-1,500 m altitude) are dominated by five species of snow tussock Chionochloa spp. Aerial hunting began in 1973, rapidly reducing deer numbers. Continued hunting (with live-capture in latter years), reduced numbers in the alpine grassland zone to near zero by 1984.
 
In 1969, 174 permanent (20 x 20 m) alpine grassland plots (spaced at 61 m altitudinal intervals) were established throughout northern Fiordland, and major grassland types were mapped. These were resurveyed in 1975. In 1984, 86 of the plots were within the central range of the wapiti herd (central Wapiti Area). Of these, 57 (covering the range of grassland types) were resurveyed to assess vegetation recovery. The following were recorded:
 
1. Percent frequency of species and bare ground in subplots along a 20 m transect running through each plot;
 
2. ‘Top cover’ of vegetation and bare ground (estimated from photos);
 
3. Tussock stature (maximum leaf length) of Chionochloa pallens or C.flavescens nearest the photo centre and its nearest same-species neighbour;
 
4. The number of faecal pellets in 10 randomly positioned circular subplots (1.26 m diameter in 1969 and 1975, 1.14 m in 1984) in each plot, to calculate a deer density index.
 
5. Site factors e.g. soil, altitude, aspect, slope.

A significant recovery of plants preferentially grazed by deer occurred on the 57 plots surveyed in 1969, 1975 and 1984. Deer showed a strong preference for grassland on more fertile soils characterised by C.pallens and large-leaved herbs, especially at lower altitudes (c. 900-1,100 m). Little change occurred in less-favoured grasslands on infertile soils characterised by C.crassiuscula and C.acicularis.
 
Between 1969 and 1984, the main overall trend was a large increase in frequencies of the large-leaved herbs Anisotome haastii, Celmisia verbascifolia, Gentiana spp. and Senecio lyallii/S.scorzoneroides, with less significant increases apparent for numerous other species. Most recovery occurred between 1975 and 1984, the period when deer numbers declined to near zero.
 
Note: If using or referring to this published study, please read and quote the original paper, this can be viewed at: http://www.nzes.org.nz/nzje/free_issues/NZJEcol10_23.pdf

Output references

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, terrestrial mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read latest volume: Volume 17

Go to the CE Journal

Subscribe to our newsletter

Please add your details if you are interested in receiving updates from the Conservation Evidence team about new papers, synopses and opportunities.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Butterfly Conservation People trust for endangered species Vincet Wildlife Trust