The islands in front of Hanson hide, ARC have long been a draw for visitors in the autumn months as they form an important feeding ground for passage waders. Aside from very dry years like this year, the islands haven't been exposed for long, if at all, given that the reserve sits on a ground water aquifer and we have no control on water levels so we are at the mercy of the elements. The table below shows the water level recorded on site on the 1st of August on gaugeboards across the reserve and with the current average height of the islands being 1.46 on this chart, it's possible to see the issue with the wetter summers of recent years.
With climate change we can expect more extremes of weather so hotter, drier years and other years being very wet and we have seen a general increase in summer levels in the last 15 years (as can be seen on the graph). We are therefore going to raise the islands on ARC to be more resilient to those wetter years as well as providing additional habitat for waders and wildfowl through the year. We are going to vary the heights across the 7 islands so that there is always going to be island habitat exposed and so that there should be additional habitat emerging earlier in the year too with the islands towards the back being higher and the ones to the front being lower to maintain viewing opportunities. We will be raising the 7 islands between approximately 1.1m and 24cm dependent on the location. The map below shows the new heights of the islands.
We will be utilising the surrounding material around the islands as per the Re-Tern Project on Burrowes Pit, this material does appear to be a little more silty, so is harder to work with, but seems to be good at attracting the waders in. Due to this material the excavator will be working itself out of the island chain during the work before breaking the causeway that was created last year that connects the islands to the shore. This breakage will create an anti-predator ditch which we will then fence with a floating rope fence, this is a new but proven technique used in Denmark and other reserves around the UK to prevent mammalian access to the islands which could cause predation issues. This fence will be installed a little later in the summer, but before levels rise too much.
We hope to start this work in the week commencing 15th August and it is predicted to take about 8 working days to complete. This will inevitably cause a lot of disturbance in the short-term whilst this work is occurring but we will keep visitors informed via our social media. We would like to thank Affinity Water for the funding for this project.
If you have any questions about this work, please do email dungeness@rspb.org.uk