On 14th August 2021 Revivel members were able to get together for the first time since lockdown .
Members were updated activities and guest speaker Keith Fitzpatrick- Matthews ,an Archaeologist ,and NHDC museum curator conducted a very interesting talk about the Upper Ivel and its surrounding area throughout the ages .
Sir Oliver Heald MP visited Radwell on 17th July 2021 and RevIvel Committee members held a productive meeting with Sir Oliver Heald, throughout which the MP reiterated his concern for both chalk streams and the wildlife living within them. The team pressed him to on the critical points affecting the river, notably over abstraction and recently pollution incidents. We expressed our disappointment with way in which the Environment Agency seems disinclined to acknowledge any historical data regarding the river’s flow We also explained that it feels as though it is the EA not Affinity Water who are reluctant to see augmentation at a volume sufficient to support the upper reaches of the river.
Sir Oliver agreed to investigate this point.
We emphasised that positive action is required urgently to address the UKs water supply and sewer infrastructure shortfalls
On 18th June 2021 a raft to detect if mink are living around Radwell lake was launched onto the water.
RevIvel members have been trained by Herts and Middlesex Wildlife Trust in how to monitor for the presence of water voles; sedges nibbled at a 45 degree angle, evidence of feeding stations and “tic tac”-shaped droppings are the “give-away” signs. It is inconclusive whether water voles are present in the upper Ivel. However in order to give them a chance, we must first ensure there are no mink in the area
The raft was kindly donated by Hertfordshire and Middlesex Wildlife Trust and Josh Kalms kindly spent some time ensuring it was in the right place.
The raft encourages mink to leave evidence of their presence in the form of footprints. The raft uses a standardised mixture of clay and sand to record the tracks over a period of 1-2 weeks.
American mink – escapees or released by animal rights activists – have caused a complete population crash in water vole numbers. The snout of an American mink is just big enough to fit down a water vole burrow and they have been almost wiped out by this voracious predator. Therefore a mink monitoring raft has been tethered in The Mill Pond which is checked regularly by RevIvel volunteers. Mink are curious creatures and would investigate the raft, leaving distinct footprints in the clay. So far, no evidence has been found.
Water voles are a keystone species – i.e. a species which has a disproportionately large effect in its natural environment relative to its abundance. Additionally, a charismatic and intrinsic part of our childhoods (think Ratty in Wind in the Willows). Therefore RevIvel is keen to help this characterful animal re-establish itself along the banks of the upper Ivel.
Sir Oliver Heald met with local pupils, who have been undertaking conservation projects as part of their Duke of Edinburgh volunteering, to hear what they have learnt and see what they have been doing in the Ivel Springs Nature Reserve. Sir Oliver and the pupils enjoyed chatting about “all things chalk stream”.
This is an article taken from the local newspaper.
A large sewage pollution of the Ivel Springs occurred at the Ivel Springs nature reserve on 27th April 2021 when a pipe transferring sewage from Baldock to Letchworth treatment works burst. A large volume of raw sewage flowed down local roads and entered ditches before eventually disappearing into the ground just above the source of the River Ivel. It is only by good fortune that the river was not directly polluted.
Members of RevIvel reported this issue to both the Environment Agency and Anglian Water. The sewage discharge lasted for over 12 hours with large volumes being discharged to ground where it has polluted groundwater. Anglian Water eventually attended and managed to reduce the discharge by tankering sewage away before mending the pipe, but the situation was made worse by their sluggish initial response.
The Environment Agency subsequently classed this as a category 2 groundwater incident (the second most serious category) but very little effort initially went in to assessing where the untreated sewage went and what its likely impacts were. Only after pressure from RevIvel was any groundwater sampling done and the results of this have yet to pick up contamination. This incident still has the capacity to pollute the River Ivel or the springs that feed it so if you ever suspect pollution is occurring please do not hesitate to report it to the Environment Agency via their hotline number 0800 807060.
Water Vole Training at Tewinbury with Josh Kalms from Herts and Middlesex Wildlife Trust
April 20th 2021
Revivel members that attended the training were Ian and Beth Hall, Kathryn Mackenzie, Craig Johnson and Catherine Wilmers
We met up at 1.0pm at the car park and Josh took our names etc. He recommended having a stick and hat for climbing through the undergrowth and parting the reeds. He took us into the reserve.
Josh explained about voles in Hertfordshire and that mink have taken over many of the vole burrows as they can squeeze into them. So there are not many places where they live. He explained about mink rafts, how they work and catch mink and that HMWT have a number so RevIvel could have a couple to spread around. Once a mink is detected by its tracks on sand or clay on the raft, a trap can be set. The mink is often caught soon after. He also said that voles are like Mars bars for barn owls, foxes and other predators!
Then he explained to us the difference between a rat and a vole. A rat is a bit bigger and has its toes pointing in the same direction compared to a vole which has its side toes splayed out. The water vole has ears half hidden by its fur and a rounded front of face; the rat has a pointed face and more prominent pinkish ears. The rat has a long tail without hairs, the vole tail is about 2/3 thirds its body length. Rat droppings are larger and usually pointed at one end.
Water voles typically eat reeds and sedge, cut at an angle (about 45 degrees) with their teeth. Josh led us to a known area where there are signs of water voles and showed us the chewed vegetation ‘feeding station’ and the nearby ‘latrine’ with poo a bit like ‘tictacs’ but bigger, 12 mm long by 4-5 mm wide. Sometimes the vole will trample on the droppings and spread them out to mark its territory. Bank vole droppings are much smaller.
Vole populations can grow fast in a year as one female can produce many offspring. They need a lot of vegetation for cover and a supply of water, still or slow moving.
Josh said he would be delighted to come to Ivel Springs in Baldock and Radwell and help us survey to see if we have water voles.
