June on our nature reserves

June on our nature reserves

©Danny Green/2020VISION

Reserves Officer Robert Morgan shares his musings on the ‘June-uary’ just gone, and breathes a sigh of relief over swallowtail numbers.

With the best part of May and June suffering wet and unseasonably chilly weather, I’m sure many of us are hoping for a warm dry July. My wife even insisted on putting the heating back on, in what has now become known as ‘June-uary’. Poor weather during the breeding season is always a worry, as our summer migrants can struggle to find enough insects to feed their offspring; that’s if nests and chicks haven’t already been washed out or perished in the cold. Purely a personal observation, but the already dwindling swallow and martin population seems to be very low this year, and singing willow warblers were missing from my local wood!

On a positive note, when the warm weather did finally arrive, dragonflies emerged in a flurry. Norfolk hawker are continuing to expand their range; in fact, three over my garden pond is a new record. Norfolk’s swallowtail butterfly population appears to have recovered from a down-turn last year. At NWT Hickling Broad and Marshes, there was concern that the consistently high winter water levels may have flooded out some of the chrysalis tucked down at the base of reed stems, resulting in fewer butterflies. A reminder that, despite continuing conservation work, this species remains at a highly threatened level. Thankfully however, during the brighter spells of weather, visitors to Hickling were treated to the delightful sight of many swallowtails on the wing.     

A swallowtail butterfly rests on some yellow flowers

Swallowtail butterfly (credit: Terry Whittaker/2020VISION)

Down the road at NWT Upton Broad and Marshes, a record count of 3,460 fen orchid was achieved. The reserve’s warden, Adam Houlgate, has stated that this is a 71% improvement on the previous year and a 3.5% increase on the previous record from 2022. The fen orchid, still nationally scarce with only a handful of UK locations in which it is found, has very particular habitat requirements. Adam concluded that the drought in the summer of 2022 may have had a knock-on effect on the lower 2023 count. As with the swallowtail butterfly, the up-keep and expansion of good quality habitat is essential for the species continuing recovery, although it is incredible that only two decades ago the fen orchid was being counted in double figures.

Also in the Broads, the Rollesby Bridge area has been given a make-over which will help more people access and enjoy the stunning views on offer at this well-loved nature spot. As part of the Trinity Broads Partnership, NWT’s work with Essex & Suffolk Water has made these significant improvements possible, and includes two fully accessible viewing areas and an accessible picnic area. 

In west Norfolk, at NWT East Winch Common, the work carried out to strip back domineering purple moor grass (a complex result of human-induced atmospheric nutrient enrichment) is paying dividends. The reserve is a mix of wet and dry heathland, dotted with ponds. Ash Murray (NWT Reserves Manager for west Norfolk) and his team have been encouraged by the results of this recent habitat restoration work and East Winch has seen an increase in many heathland speciality plants. We’ve even seen the return of some species thought lost to the site. The delicate pink flowers of bog pimpernel now carpet areas once covered by thick clumps of purple moor grass and the insectivorous oblong-leaved and round-leaved sundews are once again thriving on the margins of newly restored ponds.

Round-leaved Sundew

Sundew ©Mark Hamblin/2020VISION

Prior to this work, there had only been occasional and sporadic records of these two strange, but intriguing, insect-catching plants. Ash is also delighted at the return of petty whin, a small gorse-like shrub, previously thought long-gone from East Winch. Dodder, another unusual heathland plant, can now be found tangling its strange threads cross the newly established mats of vegetation on the scraped areas of the reserve. This odd plant is a ‘holoparasite’ and obtains its carbon from host plants, as it has no chlorophyll of its own.

In the Brecklands, breeding success of ground nesting waders has been disappointing, with no known Eurasian curlew fledging young. Already a species in significant trouble, this is a worrying blow. Only one lapwing pair managed to raise young at NWT Weeting Heath, and along with the stone curlew, predation is the main cause of nest failure. At the time of writing, just three stone curlews have made it to adolescence. However, James Symonds (Weeting warden) is confident there is still time for the stone curlew pairs to make another attempt.   

A stone curlew standing in a grassy field

Stone curlew at Weeting Heath (credit: Andy Thompson)

Top tip for July

Take advantage of the longest days of the year and head to one of our reserves to brush up on your birdsong. Many of our staff have been enjoying the Merlin Bird ID phone app, which you can use to record the sounds around you. It shows which bird is singing in real time; the ideal assistant when learning to differentiate a sedge warbler from a reed warbler, for instance!

For those who aren’t able to make it out this month, instead take a look at our new live feed, showing the view from Bishop’s Hide at NWT Cley Marshes. Tens of lapwing, a few shelduck and even a juvenile avocet were present at the time of writing. There’s plenty to see at this time of year and needing to stay home is no longer a reason to miss out.