Last Monday 31 July was World Ranger Day and an opportunity to consider the work that the Tasmanian Parks and Wildlife Service Rangers do at the Macquarie Island Nature Reserve and World Heritage Area.
One aspect of the work is to manage over 150 kilometres of walking tracks and access corridors across the island to facilitate scientific research, management programs and recreational access for expeditioners. Most traffic around the island is on foot as there is a short section of vehicle track around the station limits, occasional opportunities to move around the island by boat, and some helicopter use during the annual resupply. At Sandy Bay and the station there are also tracks and viewing platforms to enable tourists that visit the island on educational tours an opportunity to view the incredible wildlife that inhabits the island. The walking track network is extremely important for access around the island.
The track network traverses steep slopes, crosses creeks and rivers, and is subject to heavy rain, snowfall, landslips and erosion. Some of it is disappearing under the increased vegetation growth that has occurred since the pest eradication project in 2011. The latter is a nice problem to have, but keeping on top of maintenance is a big task. In recent years the Sandy Bay viewing platform was damaged by storm surge. It has slumped due to slope movement and the bridge across Red River was damaged by heavy snow and subsequent snow melt which broke the stringers on both sides of the bridge. Last year temporary repairs were made to the bridge that might not last another winter.
It was a rush to prefabricate a bridge on station and fly it to Red River during the resupply operation in May. Tom – one of the AAD Carpenters – had time to do this before he headed back home at the end of the resupply.
The next goal was to remove the old bridge and replace it with the new one before the winter snow and snow melt could damage the bridge any further and make access to the southern part of the island difficult. Matt the Plumber and Cam the Boilermaker put their hands up to help out and so we set off one cold morning to travel to Red River and install the new bridge. It’s about a 13 km, 4 hour walk, which was a little trickier than usual due to the icy and snowy conditions.
Once on site we cleared the snow away from the bridge and area adjacent to it, unpacked the new bridge components ready to install the bridge the next day which included removing the deck and then continued onto to the lovely Green Gorge hut for the night. The hour long walk from Green Gorge to Red River the next morning made sure that we were all warmed up when we started work.
We used the bearer logs and posts to roll the new bridge into position adjacent to the old one, removed the old bridge using the same technique and then slide the new bridge across into place. Once that was done we put the four posts at either end in position, bolted it all together and built a new step to connect it to the old track as the new bridge was slightly higher and longer to get it higher off the water and less likely to be impacted by high river flows caused by snow melt. A few finishing touches saw the job completed early the next day before moving onto another job in the Brothers Valley where a mud slide the year previously had taken out a section of the Brothers Track and turned it into a muddy bog.
PWS Ranger in Charge, Paul Black