Welcome to a (hopefully) regular read about some of the goings-on at Saltholme. It won’t be so regular that you can set your clock by it, but we will aim to post several times a year.
We have had a fairly busy period on the site just recently including landscaping works being carried out as part of a project funded by Natural England. The ‘Terning It Up’ species recovery project, is targeting seabirds following on from the impacts of avian flu over the last few years. The aim is to create more nesting habitat for terns.
Common terns by Lockhart Horsburgh
We have worked with a local company ZTL Contracting to renovate and add to some of the sea bird breeding areas on site. You may recall, in 2018 we carried out work on the Back Saltholme Pool island as part of the SWaP project; we lowered it and removed the messy and defunct timber surrounds. The island has since suffered from erosion particularly from the prevailing wind side and has been progressively getting smaller.
We have worked to increase the size of the island and have added rock armour around the edge to protect it from wave action and extend its life. We have also created two new islands closer to the hide, one on the leeward side of an existing feature and the other really quite close to the hide. The positions of the islands was in some way determined by accessibility, even with water levels right down, there were areas that the excavator couldn’t reach. We have set the levels (if all has gone well) so that we can flood the islands in the winter at peak water level to try and reduce numbers of roosting geese and their droppings. The use of the islands by geese in the winter leads to a quicker accumulation of organic matter than would occur if only gulls and terns were to use them in summer. This leads to some pretty decent looking compost and then, unfortunately, a covering of vegetation.
The reworked island at Back Saltholme is significantly larger
The two new islands at Back Saltholme from close to the hide
We clear the vegetation off the islands at the end of the season, and re-dress them with cockle shell to provide a bare substrate that terns can use to create a scrape in which to lay their clutch of eggs. Ask any of the estate volunteers about this task and they will tell you that it is tough work. In fact we only manage to get about a third of the island space re-dressed and in tip-top condition for Spring each year. So, by flooding the island on Back Saltholme over winter, faeces and other organic matter shouldn’t accumulate as quickly, some will wash away – hopefully many of the seeds that find their way there, and vegetation will build up less quickly lowering the amount of management required. That is the theory anyway. We have also done away with using a membrane, meaning less waste and changed the substrate to gravel. We feel it will wash away less quickly when flooded. The ‘rock armour’ is meant to be just slightly higher than the gravel for added protection.
We took advantage of having the excavator on site and were able to carry out a couple of added extras. We cleared in front of the sluice at Back Saltholme to help us control water levels as this had got severely clogged since the sluice was put in six years ago. We also lowered the level of the scrape in front of the hide so that it holds water for longer through they year, using the arisings on Saltholme West to vary topography, providing feeding areas for waders and bathing areas for common terns.
That's all for now, there is more to catch up on looking back so we'll aim for the next instalment in a couple of weeks.