Environmental Engineering Reference
In-Depth Information
information gaps. The survey methodology comprised site walkovers whereby
vegetation and habitat was qualitatively assessed and described. Species lists and site
photographic records were also compiled. Assessment of ecological signifi cance
followed the methodology set out in Norton and Roper-Lindsay (
2004
).
Gully areas were assessed using an evaluation criterion that was developed for
this site and were divided into the following three broad categories of ecological
signifi cance:
•
Low - gully highly degraded, little or no ecological values;
•
Medium - gully moderately degraded, moderate ecological values; and
•
High - gully with minimal degradation, signifi cant ecological values.
Vegetation Categories
Four broad vegetation communities were identified within the MWF project
envelope:
•
Exotic pastoral grassland;
•
Grazed indigenous snow-tussock grassland; and
•
Gully wetlands; and
•
Indigenous shrubland.
An initial species inventory recorded 125 (24 exotic, 101 native) vascular plants,
lichens and mosses within the wind farm project area during the survey. Three
common lizard species known to occur in the coastal Otago area were recorded
from the envelope area: common skinks
Oligosoma nigriplantare
were frequently
observed in open tussock grassland areas and around rocky outcrops; McCann's
skink
Oligosoma macanni
and 'Otago large' gecko were associated with rocky
tors and outcrops.
The MWF project area encompassed an ecosystem that has been extensively
modifi ed by a history of pastoral improvement, but which retains a number of natural
features: grazed and modifi ed snow-tussock grassland (Fig.
1
); gully wetlands,
small shrubland remnants, rocky tors (inhabited by lizard fauna); watercourses of
variable quality (some of which contain fi sh species listed on the New Zealand
threat classifi cation system); and potential foraging habitat for a local New Zealand
falcon population.
Of the approximately 359 ha of gully areas within the MWF development
envelope some 270 ha (75.2 %) was classed as high vegetation quality; 63 ha (17.6 %)
was medium quality; and 26 ha (7.2 %) was low quality (Fig.
2
). The high quality gully
vegetation was characterised by well-defi ned and diverse wetland areas, comprised
greater than 60 % native vegetation, including well developed Sphagnum or cushion
bog communities or shrubland, well developed, diverse and healthy tussock com-
munities, sometimes with complex rock features present along gully slopes and all
with minimal grazing pressure.
