Amy L. Whitehead Andrea E. Byrom Richard I. Clayton Roger P. Pech

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Biological Invasions

Online Resource 1

Removal of livestock alters native plant and invasive mammal communities in a dry grassland–shrubland ecosystem

Amy L. Whitehead · Andrea E. Byrom · Richard I. Clayton · Roger P. Pech

Detailed description of study areas

Areas with sites suitable for the study were chosen after a comprehensive search of land currently administered by the Department of Conservation (DOC) in the eastern South Island of New Zealand. We specifically searched for sites that had been retired from livestock grazing within the last 35 years, and where a well-maintained fence separated grazed (pastoral) sites and ungrazed (conservation) sites with similar topography and aspect and within an elevational range suitable for establishment of native shrubs including matagouri (Discaria toumatou) and mānuka (Leptospermum scoparium) (Partridge etal. 1991). By using paired sites we were also able to control for climate, soil type and local seed bank and ensure accessibility on both sides of the fence by small-sized feral herbivores/omnivores (rabbits Oryctolagus cuniculus, hares Lepus europaeus, possums Trichosurus vulpecula) and rodents (Rattus rattus, Mus musculus). Interviews were conducted with DOC staff, landowners and runholders who had knowledge of site histories and could provide details on time since cessation of grazing on the conservation side of the fence, frequency and intensity of grazing on the pastoral side of the fence, quality and maintenance of fences between pastoral and retired land, history of weed and animal pest control, and any other relevant factors such as fertiliser application and burning regimes.

Paired pastoral and conservation sites were selected within three areas: Coach Stream (1 pair), Boundary Hill (2 pairs) and Freehold Creek (3 pairs) (Fig. 1 in the main manuscript). The three areas were several to hundreds of kilometres apart and the minimum distance between pairs of sites within an area was c.200 m.

Coach Stream (43.305° S, 171.744° E). Part of the Coach Stream area was retired from livestock grazing in 1999, and management transferred to DOC. Since that time, management of conservation land has involved occasional spraying of exotic plants (mainly gorse Ulex europaeus and broom Cytisus scoparius) and removal of self-sown conifers (Pinus contorta). No fires were thought to have burned the area for 40 years and fertiliser (superphosphate) was last applied during the 1960s (Bellingham 1998). There had been no weed removal or fertiliser application for at least 30 years at this site. The stocking regime ranged from 30 to 300 ewes in the c. 200 ha paddock. (Information provided by W. Reed, M. Clare and C. Stewart from DOC, and H. Inch from Ben More Station). The area is a regenerating shrubland dominated by matagouri, bracken (Pteridium esculentum), Coprosma propinqua, Muehlenbeckia complexa, short tussock species (mainly Poa cita and Festuca novae-zelandiae) and exotic grasses. Annual rainfall at the site is c.950mm with a mean annual air temperature of 10.6°C, based on 30-year annual median data collected from nearby weather stations at Castle Hill, Mount Torlesse and Lake Coleridge Station (NIWA 2010).

Boundary Hill (43.340° S, 171.631° E). Management of the conservation part of this area was transferred to DOC in 1997 and had already been retired from grazing for at least 5years at that time. One pastoral site was in a paddock with more frequent grazing (300–400 wethers for 2–3 months of the year and 30–40 cattle for 6 weeks per year) than the other pastoral site, which had fewer sheep and no cattle. (Information provided by W. Reed, M. Clare and C. Stewart from DOC, and B. and J. Kirk, owners of Lake Coleridge Station.) The regenerating mixed shrubland is dominated by inaka (Dracophyllum longifolium), matagouri, and kānuka (Kunzea ericoides), mixed with native short tussock species and exotic grasses. Annual rainfall near the site at the Lake Coleridge Station homestead is approximately 870mm with a mean annual air temperature of 10.6° C (NIWA 2010).

Freehold Creek (44.276° S, 169.814° E). The ungrazed part of this area was de-stocked in 1982 when the land was transferred to DOC. The pastoral area was also de-stocked in late 2007 (i.e. less than 18 months prior to our surveys). Prior to 1982, the boundary fence had been only marginally effective for containing sheep. This improved after 1982 and the fence remained in good condition up to and including our study. The pastoral side of the fence was extensively fertilised c.20 years ago and had two subsequent applications of fertiliser in 2000 and 2005 at a rate of c. 125 kgha–1. The NewZealand Animal Health Board conducted some localised control of introduced brushtail possums in the area due to the presence of bovine tuberculosis, and DOC controlled wilding conifers. (Information supplied by J. Comrie and N. Bolton from DOC, and G. Burrows from Shelton Downs Station.) The vegetation at this site is mainly mānuka, matagouri, sweet briar (Rosa rubiginosa) and mixed exotic/native grassland. Annual rainfall at neighbouring Ribbonwood Station is 840 mm and mean annual temperature at nearby Tara Hills is 9.5° C.

Mt Nimrod (44.43o S, 170.86o E). Mt Nimrod Reserve and nearby Matata Reserve were destocked c. 35 years ago and are now dominated by native shrubland with native forest regenerating in gullies. Wallabies (Macropus rufogriseus) are common in the area. Annual rainfall is c. 800 mm (NIWA 2010). The pastoral sites, which are on Mt Nimrod Station, have pasture of mixed native and exotic pasture grasses and rotational grazing by cattle and sheep. Previous management of the farm involved burning sites every 3years but this ceased 15years ago. A liquid suspension fertiliser was applied aerially on the pastoral side of the fence every 3years and gorse was sprayed whenever possible by the landowner. (This information was supplied by Graham Paterson (landowner) and Adrian Cogle from DOC).

All of these study areas would have been forested (predominantly mountain beech Nothofagus solandri var. cliffortioides) prior to repeated burning by early Māori perhaps >700 years before present (Molloy et al. 1963; McGlone and Wilmshurst 1999).

References

Bellingham PJ (1998) Shrub succession and invasibility in a New Zealand montane grassland. Aust J Ecol 23:562–573. doi.org/10.1111/j.1442-9993.1998.tb00766.x

McGlone MS, Wilmshurst JM (1999) Dating initial Maori environmental impact in New Zealand. Quat Int 59:5–16. doi.org/10.1016/S1040-6182(98)00067-6

Molloy B, Burrows C, Cox J, et al. (1963) Distribution of subfossil remains, eastern South Island, New Zealand. NZ J Bot 1:68–77. doi.org/10.1080/0028825X.1963.10429322

NIWA (2010) National Climate Database. http://cliflo.niwa.co.nz (accessed 7 October 2010)

Partridge T, Allen R, Johnson P, et al. (1991) Vegetation/environment relationships in lowland and montane vegetation of the Kawarau Gorge, Central Otago, New Zealand. NZ J Bot 29:295–310. doi.org/10.1080/0028825X.1991.10416608

Scientific names of vascular plant species recorded at each site

Symbols for areas: B = Boundary Hill (2 pairs of sites); C = Coach Stream (1 pair); F = Freehold Creek (3 pairs); M = Mount Nimrod (2 pairs). Symbols for treatments: G = Grazed by livestock; U = Ungrazed by livestock for a period that is site-dependent (see text). Symbols for relative abundance: a = abundant (>50% of plots); f = frequent (21–50%); o = occasional (5–20%); r = rare (<5%). Exotic species are indicated with *.

/ B1 / B2 / C / F1 / F2 / F3 / M1 / M2 /
/ G / U / G / U / G / U / G / U / G / U / G / U / G / U / G / U /
Acaena anserinifolia / r
Acaena caesiglauca / r / o / r / o / o / r / r / r / o / r / r / r
Acaena glabra / r
Acaena inermis / r / r
Acaena juvenca / r
Acaena novae-zelandiae / r / r
Achillea millefolium* / r / r / r
Aciphylla aurea / r / o / o / r / r / r / a / r / f / r
Agrostis capillaris* / a / a / a / f / a / a / a / a / a / a / f / o / a / f / a / o
Aira caryophyllea* / r / r / r / r
Anaphalioides bellidioides / r / o / o
Anisotome aromatica / r / o / f / f / r / o / o
Anisotome filifolia / r / o / o
Anisotome flexuosa / o / r
Anthoxanthum odoratum* / a / a / a / f / a / a / a / a / a / a / a / a / a / a / a / f
Aristotelia fruticosa / r / o / o / r
Asplenium appendiculatum / r / o / o
Asplenium bulbiferum / r / r
Asplenium flabellifolium / r / r / o / o / o
Asplenium hookerianum / r / r / r
Blechnum discolor / r
Blechnum minus / r / r
Blechnum penna-marina / o / o / o / o / o / o / o / r / f
Blechnum procerum / o / f
Brachyglottis bellidioides / a / a / o / f / o / r / r / r
Brachyglottis haastii / o / o / r
Brachyscome radicata / f / f / o
Brachyscome sinclairii / f / r
Bromus hordeaceus* / f / r / r
Bromus species* / r
Bulbinella angustifolia / r / r / r / r / o / o / o
Calystegia tuguriorum / o / o
Cardamine debilis / r / r
Carex breviculmis / o / o / o / r / o / r / o / o / r / f / r / f / r / r / r / r
Carex colensoi / r / r
Carex coriacea / r / o
Carex geminata / r / r
Carex species / r
Carmichaelia australis / r / r / o
Carmichaelia monroi / o / o / r / r
Carpodetus serratus / r / o
Celmisia gracilenta / f / a / o / o / o / a / o / f / r / f
Celmisia spectabilis / o / o / r
Celmisia spectabilis subsp. magnifica / r / f
Centaurium erythraea* / r
Cerastium fontanum* / r / o / f / o / o / r / f / o / o / r / f / o / f / o
Chionochloa flavescens / o
Chionochloa rigida / o / r / r / r / r / f
Cirsium arvense* / r / o / r / r / r / r
Cirsium vulgare* / r / r
Clematis foetida / r / r
Clematis marata / r / r / r / o / r
Clematis paniculata / r / o
Clematis species / r
Colobanthus acicularis / r
Coprosma areolata / r
Coprosma cheesemanii / r / r
Coprosma crassifolia / r / r
Coprosma linariifolia / r / r / o
Coprosma microcarpa / r / o
Coprosma petriei / a / f / o / o / o / f / r / o / o
Coprosma propinqua / r / o / r / o / a / r / o / a / f / a / o / f / r / f
Coprosma rhamnoides / r / o
Coprosma rigida / r
Coprosma rotundifolia / o / o
Coprosma rugosa / r / r / o / o / f / o
Coprosma tayloriae / o / r / o / o / o / f
Cordyline australis / r
Coriaria sarmentosa / r / r / r / r
Corokia cotoneaster / o / r / r / r / r / f / r / o
Craspedia species / r
Crassula sieberiana / r / r
Crepis capillaris* / r / o / o / o / r / o / r / o / f / o / o / r
Cytisus scoparius* / r
Dactylis glomerata* / r / o / f / f / r / r / o / r / o / a / f / f / r
Deyeuxia avenoides / f / o / o / r
Dianthus armeria* / r / r
Dichelachne crinita / r / r
Dichondra repens / o / r / o / r / r
Digitalis purpurea* / r / r / o / r / r / r
Discaria toumatou / a / a / a / a / a / a / f / a / a / a / a / a / r
Dracophyllum acerosum / f / r / f
Dracophyllum uniflorum / r
Eleocharis acuta / r
Elymus apricus / r
Elymus rectisetus* / o / r / o / o / r / o / r / r / r / r / o / o / o / r
Elymus solandri / o / r / r / r / o / r / o
Epilobium alsinoides / r / r / r
Euchiton audax / r / r / r
Exocarpus bidwillii / o
Festuca novae-zelandiae / a / a / a / f / f / f / a / a / f / f / o / a / r / o
Festuca rubra* / r / r / f / o / a / a / a / a / a / o / a / f / f / o
Fuchsia excorticata / o
Fuchsia perscandens / r / o
Galium aparine* / r / r / o / o / o / r / o / o
Galium perpusillum / r / r / o / r / f / r
Galium propinquum / r
Gaultheria antipoda / r / o
Gaultheria crassa / r / o / r / o
Gaultheria depressa var. novae-zelandiae / r / o / o / r / o / r / o
Gaultheria parvula / o / o / o / r / o / o / o / r / r
Gaultheria rupestris / r / o
Gentiana species / f / o / o / r / r
Geranium microphyllum / o
Geranium molle* / r / r / r
Geranium sessiliflorum / o / o / r / o / r / r / r / o / r
Gonocarpus aggregatus / r / r / r / o / o / r
Gonocarpus micranthus / r / r / r
Griselinia littoralis / f / r / a
Hebe odora / r
Hebe salicifolia / r / r
Helichrysum filicaule / o / r / o / f / o / o / r / r / o / o / f / o
Hieracium lepidulum* / a / a / a / a / r / o / r / o / r / o
Hieracium praealtum* / f / a / f / f / r / o / f / f / a / a / f / a / r / r
Holcus lanatus* / r / r / o / r / o / r / f / f / f / o / a / f / a / o
Hydrocotyle moschata / f
Hydrocotyle novae-zeelandiae / o / r / o / o / o / r / o / r
Hymenophyllum bivalve / o
Hypericum japonicum / r
Hypochaeris radicata* / o / o / o / o / r / o / f / f / f / o / f / r / f / f / f / f
Hypolepis millefolium / o / f / f / f
Isolepis aucklandica / r / r
Juncus antarcticus / r
Juncus conglomeratus* / r
Juncus edgariae / o
Juncus effusus* / r
Kirkianella novae-zelandiae / r
Kunzea ericoides / o / o
Lagenifera petiolata / r / r
Leptospermum scoparium / o / f / f / a / o / r
Leucopogon colensoi / a / a / a / a / r / r / o / r / f
Leucopogon fraseri / f / a / f / f / f / f / a / a / f / a / f / a / r / o / o
Leucopogon nanum / f / o / r
Lichens (all) / f / a / f / f / a / a / o / a / f / o / f / a / f / o / o / o
Linum catharticum* / r / r / r / o / r / f / r / o / r
Lolium perenne* / o
Lotus pedunculatus* / r / o
Luzula rufa / f / f / f / o / o / a / o / f / o / f / r
Lycopodium fastigiatum / r / r / o
Lycopodium scariosum / r
Melicytus alpinus / r / r / o / r / o / o / r / f / o / f / o / o
Melicytus ramiflorus / r / o
Microsorum pustulatum / r / o / f
Microseris scapigera / r / r
Microtis unifolia / o / o / r
Mimulus moschatus* / r / r
Montia fontana / r / r
Mosses (all) / a / a / f / f / f / f / r / f / o / f / o / a / f / f / f / f