This autumn got very wet very quicky at the Fenland NNRs. Woodwalton Fen NNR is used as a flood storage area by the Middle Level Commissioners (who are responsible for water level management and flood prevention in the area). The second half of October saw enough water come into the system that we were given warning that they might need to flood Woodwalton Fen.

Happily, the water level didn’t quite reach its overtopping point, so the NNR was not flooded this time. However, the amount of rain that did fall caused the ground conditions on site to deteriorate rapidly. This happened much earlier than we usually expect. Therefore, we took the decision to temporarily close the site in order to prevent damage happening to the tracks too early in the winter. If the site had remained open and the rides had been damaged, it may have resulted in us having to shut the site for a longer time period later in the season or, worse still, could have caused damage to the botanically rich ride-side habitats that are such an important part of the NNR. 

As the winter continues, further closures of certain parts of the site, or of the site as a whole are possible- dependant on weather and how this impacts the condition of the site. We thank you for your understanding and cooperation so far, and in advance for your further cooperation through the rest of the season. Please keep an eye on the website and our Facebook page for updates. 

Thankfully, we had managed to do the majority of the habitat management works we were hoping to get done at Woodwalton before the wet weather hit. One such bit of management was to the north of Rothschild’s Bungalow, where we had contractors take out around a quarter of a hectare of scrub.

We undertook this scrub removal as this area of the NNR was one of the last places we have records of Marsh Lousewort on site. This lovely little flower is considered to be of “least concern” on the Red Data List for Great Britain but is considered “Vulnerable” on the England Red Data List and is very scarce in Central England. Woodwalton Fen is the only site with records in Huntingdonshire in the recent past (though the last record here was from 2011). Declines in Marsh Lousewort populations and distribution are likely attributable to drainage of wetlands. Marsh Lousewort is annual or biennial, and likes open conditions, so hopefully removing the scrub, opening up the habitat and creating some bare ground creates the right conditions to see the species return. We had the contractor grind out the stumps of the trees and scrub that was removed, which should allow us to cut and collect the vegetation in this area on an annual basis in years to come.

As well as just being a lovely flower that is quite rare regionally, Marsh Lousewort has an interesting ecology that makes it of conservation importance. It is a hemiparasite; it gains some of its nutrients through photosynthesising but also gains some nutrients by taking them from other plants. It does this by forming a connection to its host called a haustorium, through which it removes water, organic compounds and minerals.

Marsh Lousewort normally parasitises vigorous grasses, sedges and rushes. This parasitism reduces the vigour of these plants, thus allowing less competitive species the chance to flourish. Thus, Marsh Lousewort can contribute to a higher floral diversity in the places it inhabits. It is possible that if we can get Marsh Lousewort to naturally re-establish at Woodwalton, it could help to improve the condition of the site in the areas where it is found. We may also be able to use re-established plants as a seed source for introduction on to restoration areas in the Great Fen, hopefully improving floral diversity in these areas too.