Friday 22 July 2022

The big guys move in

 

Reserve updates July 2022

The next stage of our engineering project at the reserve has now started. The arrival of some huge machinery, much of which passes through the car park, highlights the need for the site to remain closed for visitors.



Work has now started on the removal and redistribution of Tophill ‘mound’. This is to make way for the new treatment works and filtration beds. Truckloads of rubble etc are being taken from behind the residential area to one of two sites on the reserve: the east side of D reservoir and the south end of O reservoir. The rubble is going to create two new mounds upon which our two new hides will be situated. This will allow access for all visitors and fabulous views over the reservoirs and in the case of O reservoir, the wider Hull valley.

Today (Tuesday 19th) I accompanied the site manager to get some footage of the work in progress. Nearly 80 % of the mound material that will be the base for the new D reservoir east hide is now in place, raising the ground level so I could see over the reservoir wall. After each 20cm depth of material has been spread over the surface a second machine compacts the material down, thus making the mound a solid structure. At the front, facing the reservoir there will be a gabion wall to further support the mound, a concrete platform will form the base for the new hide and the access path will start and finish at opposite sides of the D woods.


Preparation of D reservoir mound



The new mound which will allow the new hide overlooking O reservoir is a much bigger structure and is less complete. Once built the top of the mound will sit 6m above the ground level, approximately the same height as the old hide roof. On top of that the new hide, which will be two storey will be positioned.


Preparing O reservoir mound


Dumping material in preparation for O reservoir mound

Each wagon carries 30 tonnes of material every 15 minutes to each site from the area of the new treatment works, passing along the reserve access road each time. Due to this volume of machinery moving at such a frequent rate we can no longer conduct any guided walks in this area at present. Once the situation changes and we can safely accommodate visitors on reserve walks then we will schedule and advertise these.

Late June and July are sometimes the quietest times of the year for birdlife. Raising new fledglings is the biggest issue for our woodland birds and there is a lot of alarm calling and contact calling within family groups of tits, thrushes and warblers. On the wetlands, the black headed gull chicks have now all fledged leaving south marsh a lot quieter. Volunteers and visitors on the guided walks have seen five juvenile marsh harriers on south marsh west, as well as one juvenile near south lagoon. The pair of oystercatchers successfully raised two chicks and we hope that four shelduck reached a viable size after an initial count of eleven youngsters on south marsh east, a welcome sight to see this species breeding at the reserve. We hope that we have seen some success in breeding for common terns with an increase in the number of birds on south marsh this year, a maximum count of 16 birds, far more than last year. Gadwall, mallard, greylag, coot, tufted ducks all appear to have had a successful breeding season on south marsh.

On our guided walks visitors and volunteers have regularly seen bittern, in some cases two at once on south marsh west. We have yet to record any evidence of breeding but we wait in hope to catch a youngster on the move. Hopefully the presence of this iconic reedbed species is a result of the management practice that took place over last autumn and winter, when different areas of the reedbed were cut to a variety of levels and a new channel dug along one edge.


Visitors enjoying a guided walk

                                                             Bittern  Photo  Credit Maurice Dowson






There have been some signs of autumn, with a few waders passing through recently: common sandpiper, wood sandpiper, ringed plover and ruff have all been sighted, all on south marsh.

North lagoon has now lost all of its water and the exposed mud has become very dry and cracked within the last few weeks with the hotter weather. We had hoped that if it had remained wet then passage waders may have been enticed down to feed. The water however has rapidly evaporated quickly than anticipated, therefore will probably be dredged earlier than planned, ready to be put back in use for the water works and be filled again. The ‘No Fishing’ sign is certainly being adhered to! Kingfishers have been noted feeding regularly on south lagoon and south marsh, spreading themselves around the reserve as they usually do, following fledging.


North lagoon July 2022

Many of our wildflowers are now passing from bloom to seed, with the bee orchids and the common orchids now nearly over. The yellow rattle, an important flower in our meadows is also setting seed and the seed has been collected. This is the plant that outcompetes grasses which can sometimes take over. It also helps to make the meadows nutrient poor, ideal conditions for many wildflowers, so it is an important plant. Our volunteers have been visiting other local wetland areas to collect a range of other seeds. These will be planted and propagated in our new polytunnel, due to arrive on site soon, then they will be introduced to various areas on the reserve. We have already successfully introduced some bog bean and marsh cinquefoil in the reception pond. Our main problem was protecting the plants from being eaten by water voles – now that’s a good problem to have! In preparation for the work that will be carried out in the polytunnel, volunteers had a very informative visit to Nosterfield nature reserve, near Ripon. Here they have a very established polytunnel and wet beds in which they grow wetland plants. Each species requires different water levels and the set up at Nosterfield allows for this with separate areas with different water levels. Once plants have been raised the team then distribute plants to other reserves and partnerships, something that we aim to do ourselves in the near future.




Flowering bog bean


Our own wetland plant propagation in reception pond


Nosterfield nature reserve wetland plant propagation set up


Nosterfield nature reserve poly tunnel 

Our volunteer team, as always, have been busy learning new skills on a few events this week. Last year we were lucky to have scything enthusiasts Martin Stevens and Heidi Marwan of the Scythe Association of Britain and Ireland approach the reserve for a venue to exercise their skills.  A resurgence in interest in this technique has seen the widespread adoption of the much lighter and, in modern hands, more efficient Austrian scythe which makes the activity much more user friendly, and in many comments ‘a joy to use’. With the need to start cutting our hay meadows on site this essential training has meant we can start this major task in a way that does not create hand arm vibration, emit fumes and carbon, or need a spill kit, a three day specialist course and personal protective equipment to operate. All benefits for both the reserve and the volunteers.




                                                Scything at Boltby reservoir, autumn 2021


                                                            Boltby meadow July 2022

At Boltby reservoir near Thirsk scything last year has helped deliver stunning meadows of oxeye daisy and bethony which are home to adders, palmate newts and the rare argent and sable moth.  Near Dunswell on the outskirts of Hull are ‘adits’ – horizontal bore holes cut into the chalk which gather water beneath protected meadows, one of which has been earmarked for biodiversity enhancement to protect species like lapwing and skylark on the very boundary of the city, and it is here volunteers are training on the tools under Martin and Heidi’s instruction on a classic hay meadow setting.  Likewise, another event at Yorkshire Water’s Brooks Bank Farm near Sheffield hosted a scything masterclass by professional Danny Hodgson, in conjunction with the Sheffield and Rotherham Wildlife Trust, to manage meadows and wader scrapes as part of the Sheffield Lakeland Landscape Partnership.  The partnership has allowed us to manage meadows, woodlands and wetlands on a landscape scale to deliver bigger, better and more connected wildlife conservation.

We will continue to work to improve and maintain our habitats on the reserve whilst the different engineering projects continue around us. We will keep visitors updated as much as we can, both on the works and the wildlife that continues to thrive at Tophill Low. We greatly value your support and understanding whilst the reserve is closed and thank you for your interest in Tophill Low.