Fritillary Watch - 6th June 2013
The following article from Natural England explains the events leading to the reduced numbers of fritillaries in the meadow this year.
The case of the disappearing fritillaries
North Meadow NNR is an ancient flower-rich hay meadow at the edge of the small market town of Cricklade in North Wiltshire.
The 110 acre site is mainly owned by Natural England and we jointly manage it with the Cricklade Manorial Court. It is Lamas land, which means that a hay crop is taken in July then the aftermath is grazed from August 12 to February 12, as long as ground conditions allow.
What makes North Meadow NNR really special is that 80% of the British population of snake’s head fritillaries can normally be found there...but this year these beautiful flowers were few and far between.
Where have all the flowers gone?
In late April 2012, flooding started on North Meadow and it continued until the last flood on 20 March this year. During a summer flood, the site can become too wet to allow farm machinery to do the annual hay cut. If the hay is not cut, the vegetation becomes tall and then falls over, creating a mat that rots down. Smaller flowers are then smothered or shaded out and will not appear the following season. To add to this, some species cannot tolerate being wet during the growing season and will die as a direct result of being flooded, so many species can be lost.
Botanical monitoring has been carried out annually on the site since 1998, which represents the longest available data set for this grassland type within the UK. Early data collection was funded by Defra, and since 2008 the survey work has been carried out by the Floodplain Meadows Partnership (FMP). This group has continued to analyse and interpret the data in the context of changing hydrological and management activities at the site. Since 2010 the monitoring work has been funded by the Manorial Court of the Hundred & Borough of Cricklade, through their HLS agreement for the site.
The monitoring undertaken by the Floodplain Meadows Partnership has revealed some useful information. It showed that following the summer floods in 2007 & 2008, where farm machinery was able to cut the hay the monitored plots retained their species diversity. However, the plots in those areas that were too wet to cut for one year lost many species. Those that were not cut for two years continued to lose their wildflower richness.
North Meadow was too wet to either take a hay crop or be grazed by cattle in 2012. To compound this, the cold wet spring this year delayed the emergence of Fritillary shoots until 8 April - a full month later than in 2012. The dense matted thatch that lay over much of the meadow like a thick blanket then blocked out light and air to the developing sward beneath. The Floodplain Meadows Partnership’s annual fritillary count took place on the 23 April. It was the quickest ever count as very few fritillaries were found.
After consultation with the Floodplain Meadows Partnership and botanists as to how best to manage this situation, the decision was taken to try and remove as much of last year’s thatch as possible. This would be done as soon as the meadow dried out enough to allow tractors on and as a result the light would be able to get through to the developing grasses and herbs.
Progress so far
30 acres of the meadow has been mown and baled, and 15 acres have been chain harrowed. Recent heavy rain has halted the work for the time being, but will continue as soon as possible.
The fritillaries were most abundant in an area of 5 acres on the north east side of the site, as well as other small colonies which have not been mown.
Visitors and guided walks
Many guided walks had to be cancelled, but the ‘open weekends’ continued in the nearby Fritillary Tea Rooms where the Reserve Manager , High Bailiff and Town Crier of the Manorial Court gave illustrated talks about North Meadow to groups of visitors.
Find out more
Read about the snake’s head fritillary and North Meadow NNR.
Read the Independent’s article, Why half a million fritillaries didn’t make it this year .
For more information contact Anita Barratt Tel 07795316191