Spring rains bring calamity at Dunston’s Cave

When the rains finally arrived in April, they were more than welcome, in many respects. But they did bring with them some problems for Spring Hill, with many dried trees and branches absorbing the rain and falling across the estate’s trails.
Some of these damaged the metal railings on steeper sections of the trails, and repair work is now in progress. However, down at Dunston’s Cave – the home of our famous Oil Bird Colony – a large tree above the entrance to the gorge uprooted itself and fell down into the stream below! It hung down over the front of the cave like a huge pendulum, blocking anyone from entering, and damaging the railings and walkway into the cave. And when it fell, it brought down all the neighbouring vines and some smaller trees, all of this leaving a large opening in the forest canopy above the gorge.
Those familiar with Dunston’s Cave will appreciate that it is really a river gorge through which the stream flows. Parts of the gorge meet at the top forming a tunnel, but this with some openings to the sky. The loss of the forest canopy above the cave caused a lot more sunlight than usual to shine down into the gorge, and this gave rise to concerns for the birds with the interior of the cave becoming brighter in the daytime.
We had no choice but to cut the dangling tree trunk and then remove all of the branches and vines from the cave entrance. This was not only to restore the entrance, but to ensure that future heavy rains did not wash it all into the cave, possibly creating a dam inside. The work had to be done with chain saws, but the birds seemed to accept this, and subsequent bird counts indicate that, although the birds are deeper into the gorge, they are all still there.
Steps are being taken to revegetate the slopes above the cave, so that the original canopy will eventually return. However, the good news is that despite the trauma of the crashing trees and the subsequent clearing work, our Oil Birds seem to have settled back comfortably into Dunston’s Cave.
June 2010