April finds the ‘Dawn’ Chorus in full voice long before sunrise. The ringing, repeated notes of the song thrushes usually break the silence when it is still pitch dark, and great tits, blackbirds and wrens soon follow. To fully appreciate this outpouring of song one must rise at least an hour before dawn.
The males will be singing, particularly if a mate is needed, off and on through the day, but with nothing like the enthusiasm of the early hours of the morning. Where the light from a street lamp provides artificial daylight, robins will sing both night and day, and are often mistaken for nightingales.
Other migrant songsters are with us too, with chiff chaffs’ repeated notes constantly uttered in the treetops. They’re joined a little later by the willow warblers, their delightful song a promise of long summer days to come. Although the summer visitors are now arriving steadily from the south, the birds from the north that came here for the winter are still around. They may overlap for several weeks. By the side of a wood where blackcaps are singing, the northern thrushes – redwings and fieldfares – may still be found feeding in a field.
The start of April is a time of increased engagement with members of the public, particularly in an effort to protect nesting birds, with ground-nesting birds being particularly vulnerable at several of our sites. At NWT Holme Dunes, we rope areas off where beach nesting birds have settled, but we also have a team of volunteers (thanks to all who answered our call out) helpfully advising the public about responsible dog-walking on the beach during the breeding season.
In the North-west of the county at NWT Tony Hallatt Memorial Reserve, an interesting project named ‘WetScapes’ is underway, part of which includes the re-instatement of a long lost stream that once flowed across the reserve. Despite the difficult working conditions this winter, contractors and staff have completed the first phase of the WetScape project.
The long lost stream, now back in business!
Reserves Manager for West Norfolk, Ash Murray explains: “The former stream, we estimate, was diverted off site over 200 years ago. William Faden’s map of Norfolk (1797) showed that, even back then, the stream had been diverted to flow around the reserve. However, despite having been drained and planted with trees in the intervening period, following prolonged rainfall, the course of the former stream was evident as wet, rush-filled linear hollow.
Staff carried out soil coring [sampling the vertical layers of the soil with a purpose-built tube style tool] to determine the approximate depth of the former stream and to plan the best locations for a series of six inline pools. Water control structures will be installed in the autumn to help divert water into the stream, however, even without these, the stream is flowing well.
So far, it has been used by kingfisher, green sandpiper and little egrets, and on the banks numerous birds have been feeding along the bare margins, including stonechats and pied wagtails.
The shallow gradient and bare banks will provide an ideal habitat for a range of plants and invertebrates that have become scarce over the last century, including lesser water plantain
Baldelia ranunculoides, Apple Fountain-moss
Philonotis fontana and the Silver Colonel
Odontomyia argentata.”
A new pond, created as part of the WetScapes Project
As part of the WetScapes project, staff and contractors have been creating new ponds too.Ash is particularly pleased with the way the ponds have turned out. “The ponds have shallow, sinuous margins and the irregular shapes of these bare margins, coupled with the fact that they have constant seepages of water flowing over, creates a set of conditions that were once far more widespread, but that have been lost over the past 100 years due to improved drainage, a reduction in livestock, an increase in atmospheric nitrogen deposition coupled with climate change. As a consequence, a large suite of what were once widespread species have become very rare or lost completely. The new pools on the Tony Hallatt Memorial Reserve and Grimston Warren will provide ideal conditions for a wide range of these species to recolonise”.
As well as restoring and creating a variety of wetland features, the WetScapes project has also enabled staff and contractors to cut and collect dense over-shading rushes from an area of degraded mire on the reserve. This has improved light penetration and reduced water loss via transpiration. Ash continued: “Amazingly, there has already been a positive response with scarce species, such as lesser cow’s-horn bog-moss
Sphagnum inundatum showing an increase in extent across the cut plot.”
In order to enable scrub to regenerate, contractors have also installed several fences parallel to existing boundaries. “These will provide a ‘soft’ boundary, thereby reducing the potential for collisions with fences by nightjars and creating dense scrub for a wealth of invertebrates and their insectivorous predators, again, such as nightjars”.
Close by, at NWT Grimston Warren, the digger was employed to create low ‘clifflets’ and bare, open patches in the heath. Grimston Warren is one of the most important sites for bees in Norfolk, supporting two species that occur nowhere else and several that occur in only a few other places in the county. These creative features and bare scrapes will provide nesting and basking habitat for a whole range of other sun-loving invertebrates, their parasites and predators.
Top tip for April:
This month, we’d recommend the trip to
NWT Weeting Heath to see the newly arrived stone curlew. The female of our regular pair fittingly arrived on Mother’s Day! The male turned up a few days later and has been calling constantly, ensuring everyone knows that it’s his plot again.