Macquarie Island non-native plant survey data 2010-11
In 2010-11 a whole island survey or Macquarie Island was undertaken by Justine Shaw and Aleks Terauds. Quadrats (1m * 1m and 10m *10m) formed the basis of these surveys. At a minimum, quadrats were surveyed at the centroid of each 1 km * 1 km grid square. Other quadrats were surveyed along the survey track depending on the presence of non-native plants. Native plant coverage was also recorded in most quadrats.
The download file contains an Excel spreadsheet. The spreadsheet contains three worksheets, two of which contain keys to the third worksheet (the data worksheet). Information from the two keys is summarised below:
Key to Field Headings
Island was divided into 1 km x 1 km cells (see associated shapefile). A ‘track’ of minimum length 750 m (and usually between 1-2 km) was walked through each cell from 1 km centroid to 1 km centroid (again with 1 m2 and 10 m2 quadrats).
At a minimum, the centroid of each cell was surveyed for alien plants using a 1 m2 and 10 m 2 quadrat. Other quadrat based surveys were carried out along the track (again with 1 m2 and 10 m2 quadrats) when alien plants were detected.
In most cases native plant coverage was also noted in each quadrat. Percentage cover was calculated for Poa annua, Cerastium fontanum, and Stellaria media.
Number of plants was also documented for Cerastium fontanum and Stellaria media, not Poa annua as individual plants can’t be easily identified.
The presence or absence of alien species was recorded along each track. For analytical purposes, each track was divided into 10 m segments,
and the presence or absence of alien plants in these was then used to calculate the ‘proportion’ of each plant in each 1 km cell.
For example, a 1km track through a cell has 100 ten metre segments, if 40 of these had Poa annua present, then the cell was allocated a proportional value of 40% for Poa annua (see shapefiles for actual data and visual representation).
ID Cell ID
LongitudeI Centroid of 1km cell longitude
LatitudeI Centroid of 1km cell latitude
C_poa 1x1 m quadrat percentage cover of Poa annua - note no number of plants for Poa annua because separate plants can't be identified
C_cfA 1x1 m quadrat percentage cover of Ceastium fontanum
C_cfN 1x1 m number of Cerastium fontanum plants in quadrat
C_smA 1x1 m quadrat percentage cover of Stellaria media
C_smN 1x1 m number of Stellaria media plants
Q_poa 10 x10 m quadrat percentage cover n of Poa annua -- note no number of plants for Poa annua because separate plants can't be identified
Q_cfA 10 x10 m quadrat percentage cover of Ceastium fontanum
Q_cfN 10 x10 m number of Cerastium fontanum plants in quadrat
Q_smA 10 x10 m quadrat percentage cover of Stellaria media
Q_smN 10 x10 m number of Stellaria media plants
Q_veg native veg composition - see attached worksheet for key
Q_rab rabbit grazing present? (centroid only)
Q_die Azorell dieback present? (centroid only)
Vegetation key, numbers are percentage cover, will generally add up to 100
az Azorella macquariensis
fm feldmark
bare no veg
hb herbfield - Megaherbs - mainly Pleurophyllum
sc complex of short grass, typically Agrostis, Luzula, Festuca,
co Colobanthus spp. (also sometimes colo)
by bryophytres
mr mire
pa poa annua
sg short grassland
sh short herbs, Acaena spp, Cardamine sp., Montia sp.
sgh short grass herb complex
ttg tall tussock grass, typical Poa foliosa
DR damaged by rabbits