If you have been to Woodwalton Fen recently you may have seen a couple of new culverts on site. These culverts have replaced two rather old bridges that were beginning to become unsafe for vehicles. Culverts have the benefit of being a bit lower maintenance than bridges but come at a slight cost as they reduce the flow of water around site. In the locations that we have installed culverts, we were able to do so because flow of water in the ditches concerned is not too critical to the positive management of the site as a whole.

Whilst installing the culverts may have slightly reduced the flow in a couple of ditches, in the past few months we have also had a water control structure replaced in the middle of the National Nature Reserve (NNR) to aid us in moving water around the site. The old control was non-functioning; it had completely seized up and the ditch either side of it had largely silted up. The new structure should allow us to better control movement of water into the south of the site’s central hydrological unit and thus help us to maintain the water levels to best meet our conservation objectives.

Controlling water levels is of central importance to management at Woodwalton Fen. However, in recent years we have had some issues with water flooding onto the NNR from the drainage ditch along the south of the site. Whilst getting water onto our wetland site can be necessary sometimes, getting nutrient-rich drainage waters outside of our control is quite likely to be a factor causing deterioration of condition in the south of the NNR.

Thankfully, the drain is managed by the Middle Level Commissioners (MLC) who are a member of the Great Fen partnership. This autumn, the MLC dug out clay from the drain and used this to build up a bank. This work should not only increase the capacity of the drain, but also increase the height to which the water in the drain must get before it floods. If this work manages to decrease the frequency of flooding events at the south of the NNR, we are hopeful that this will help us halt the deterioration in the plant communities at Woodwalton Fen.

Safeguarding the plant communities on our nature reserves is a major driver of our work across the Great Fen. Trying to maintain suitable conditions is only one piece of this puzzle. The small size of the NNRs means only small populations of species can be supported on the sites themselves are therefore much more vulnerable to extinction. If we can help these populations expand onto the restoration land in the Great Fen, we hopefully increase their chances of surviving into the future. In the past few months, we have tried to aid the special fenland flora of Woodwalton Fen to expand into restoration land on Darlow’s Farm; the land immediately adjacent to Woodwalton Fen that became the first restoration area of the Great Fen when purchased by Natural England in 2002.

In the summer, we collected seed from a variety of plants across the site. These included water mint, yellow flag iris, yellow loosestrife, marsh thistle and gypsywort. In some areas, we used a mechanical seed harvester; this is pulled behind a vehicle and brushes seed off plants and into a hopper. The seed harvester was used in areas with particularly important and diverse plant communities. We also collected seed from a few specific species in a more targeted way; for example, species known to be food plants for rare invertebrates.

The collected seed was processed to enable it to be stored without fear of deterioration. In December, we cut and cleared vegetation in a number of areas on Darlow’s. In late December, the collected seed was spread onto these prepared areas. We will keep an eye on how things progress in these areas in years to come; hopefully we will begin to see some of the special plants of Woodwalton Fen gaining a foothold on Darlow’s Farm.

Planting these seeds on Darlow’s Farm marked the end of an era. This was the last task that our colleague John Kerr led during his stint with Natural England as Reserve Manager on our Fenland NNRs before moving on to new adventures. John put in 8 years of passion and hard work across the Great Fen (and beyond, working across Natural England NNRs in the region as well as on sites managed by partner organisations like the Wildlife Trust BCN). John’s dedication, work ethic and quiet kindness will be much missed by all those he worked with during his time here. We wish him all the best for the future!