Wednesday 24th July signals the beginning of an exciting phase for the reserve with the mobilisation of the contractors for the Natural England Species Recovery Programme funded project to create 15 islands on New Excavations and Dengemarsh Hide. The work will be undertaken via an excavator mounted onto a pontoon which worked successfully on the Re-Tern Project in 2017, this pontoon will be pushed around the lake into position where it will dredge up the shallower remnants of the causeways which fragment the lake to create islands. Due to the depth of the water off the causeways (between 10-13 metres in places), the island locations are dictated by the causeway routes. These islands will be higher and larger than some of the islands on other waterbodies of the reserve and by the end of the project there should be an additional 2 hectares of island space for seabirds to nest on each year. The two islands created in 2023 have already proven to be a success with Common and Herring Gulls nesting on them, so we have high hopes for the 13 remaining islands. When the remaining 10 islands have been created on New Excavations, the contractors will demobilise and move to Dengemarsh where there will be 3 new large islands right in front of the hide on some shallow peninsulas present there.
Due to the reserve being on a groundwater aquifer and one of the most highly designated nature reserves in the country we have no control on water levels and an inability to import materials in to create islands, this leaves us with the only option of dredging shallower material to create habitat. Over the past 7 years the team will have created 72 islands for seabirds on the reserve with great success until a combination of weather related abandonment in 2021, which can cause the loss of the colony for a few years and then the double hit of avian flu, which caused high seabird casualties on the reserve, and then climate change induced record water levels combined with a cold, wet spring meaning that water levels have been beyond the predicated extremes that calculations have shown. The seabird populations are now starting to recover with common terns nesting on ARC and Burrowes Pit, albeit in small numbers, on islands, that without the hard work of the staff and volunteers simply wouldnt have emerged from the water yet, so the team have high hopes for the success of this project.
We have recognised that viewing across New Excavations is hard when beyond Christmas Dell, so we will be opening two new viewpoints to enable everyone to enjoy the new islands, one between Dengemarsh Hide and the Hookers Viewing Ramp and a further one on the Discovery Trail, these will be installed in August/September as construction work progresses.
Throughout the construction phase of the island project there will be inevitable disturbance from in front of Christmas Dell and Dengemarsh Hides respectively, but this does provide excellent viewing opportunities of conservation work in action. Work is expected to take up to 8 weeks, we hope it will be less than this, but it very much depends on many factors.
Further seabird rafts and anti-predator fencing will be left to install in Spring 2025 after the risk of winter storms has subsided
This project also covers habitat creation for Medicinal Leeches and Marshmallow moths through the removal of fringing willow around the lake which provides warmer, shallow water for leeches and the opportunity for the Marshmallow plant, the foodplant of the moth, to thrive. Much of this work was completed last winter, but further work is required in the coming months as well as surveying for the relevant species which the reserve team are in the process of starting.
This is what promises a transformative project in the heart of the reserve, so please keep checking in for progress updates