I have seen many habitat changes during an amazing eight and a half years of working at Brockholes, with the meadows, woodlands, hedgerows and ponds supporting an increasing abundance of wildlife. However, despite our best efforts, the islands and reedbeds are struggling to become the wading bird paradise we want them to be.

Now hope is on the horizon, thanks to grant providers Biffa Award and National Highways, who are funding phase one of our ambitious habitat remediation and enhancement project. This spans Meadow Lake and No.1 Pit Lake, aiming to reinstate water controls, create large muddy islands ideal for wading birds, and lush extensive reedbeds, no longer choked with willow and alder trees. These may sound like simple aims, but their implementation on a maturing nature reserve is tricky.  Having spent years assessing problems that the islands and reedbeds face, we know there are three big challenges, but also three solutions.

Challenge 1: Water level control

When Lancashire Wildlife Trust bought Brockholes in 2006, the lakes were former sand-extraction pits, left to naturally fill with water. The ability to control water levels is an invaluable tool in wetland habitat management, so ditches, culverts and sluices were installed. For several years these worked well, but problems then arose, with one sluice badly damaged in an extreme flood event and the other washed away entirely, making it impossible to raise water levels. Silt then accumulated in ditches, making it impossible to lower water levels.

With no means of water control the reedbeds and islands became too dry and were quickly colonised with abundant terrestrial vegetation. Additionally, the invasive plant Crassula helmsii began to flourish, favouring water with no flow. Crassula grows so vigorously in static water that it forms a near-impenetrable layer, cloaking the shallow water and island edge habitat.  

Solution

We realised we must reinstate water controls for both lakes and that the control features must be able to withstand flood surges. An ability to hold levels high or low and to generate significant water flow at regular intervals would be a first step towards remediating islands and saving our reedbeds, but it would require specialist input and it would be expensive.

Challenge 2: The islands are too high

The islands in Meadow Lake and No. 1 Pit Lake were deliberately formed as wader habitats and initially their bare mud and stone attracted nesting lapwing, ringed plover, oystercatcher and avocet, plus nationally notable numbers of migratory whimbrel, gaining the reserve recognition as a locally designated Biological Heritage Site.  However, it has since become clear that the islands were formed too high above the water, so were never waterlogged or submerged. That meant that they very quickly went from muddy bare ground to terrestrial tall grass and scrub, despite our best efforts to mow and scrape them. The vegetation was high enough for foxes to live on them year-round and sadly all habitat value for wading birds was lost.

Solution

To reinstate wet, healthy and larger reedbeds, we need to remove encroaching scrubby trees and using our new water control features to inundate them in winter, increasing habitat value and drowning out new tree seedlings. Along lake edges where reedbeds have failed due to being too high we will lower and widen them, so they too can be flooded in winter.

The reality of achieving these objectives entails moving thousands of cubic metres of soil, with care and consideration for nearby habitats and resident wildlife. It is a daunting prospect, especially when working in autumn and winter weather, to avoid disturbing nesting birds. We have commissioned trusted contractors, who will be on the reserve October to December 2024, with excavators, dumpers, bulldozers and a crane.

Notably, throughout this first phase of the project, reedbeds in the southern half of Meadow Lake, the western and eastern edges of No.1 Pit Lake, and the entirety of nearby settlement pits and Ribbleton Pool will be left undisturbed, ensuring bittern, water rail and roosting flocks of starlings still have reedbed available to use.

Find out what's been happening so far in our latest blog