Monday, 7 July 2014

PatchChat: Drew Lyness on Lemsford Springs, Hertfordshire

Birding for me has changed significantly in recent years. For the last year I have been spending the majority of my time birding in the wonderful county of Norfolk and we all know about its sparkling reputation among the birding community. However, this is an extremely significant upgrade from where I have spent the 8 years prior to my relocation to Norfolk. This is because I spent most of my teenage years birding Hertfordshire… yes, Hertfordshire. It is landlocked, in close proximity to London and a place where finding literally any wading bird other than Lapwing should be considered a noteworthy. I have had days where I have visited some of the counties most highly rated birding spots like Amwell Nature Reserve, Tring Reservoirs and Tyttenhanger Gravel Pits and still barely scraped 40 species in a day. 

Despite this, there are a few reserves in the county I have fallen in love with because of both their character and resident species. They helped me develop an ongoing passion for nature and none more so than Lemsford Springs. This tiny nature reserve managed by the Herts and Middlesex Wildlife Trust on the edge of Welwyn Garden City is a haven for nature and, in winter, this reserve has a special secret which provides salvation for much of the local wildlife. Lemsford Springs is a brilliant nature reserve which shows how historical human engineering and management can create fantastic home for nature. It is at the forefront for some incredible scientific research and still remains a fantastic example of how a nature reserve is capable of bringing the local community closer together. 

 This tiny reserve (just under 4 hectares) was once a fully functioning Watercress bed. It was one of the main suppliers of watercress to surrounding towns as well as London. Watercress used to be an important part of people’s diets because of its high vitamin C content and it was even claimed to be a cure for diseases such as scurvy. By making use of the area’s natural springs a wide shallow spring fed channel was created running alongside the River Lee, ideal for growing Watercress. From one side of the reserve, the springs release fresh water which slowly travels south through the channel and empties out into the river lea on the other side. In 1970 Lemsford watercress bed were bought by the Wildlife Trust for just £2500 from the cress farmer who owned the site. The site then became known as Lemsford Springs Nature Reserve. Two hides have been installed and the reserve is open to all, although it is kept under lock and key. To gain access the keys are kept in the porch of the wardens house which is next to the reserve entrance gate.

Since its purchase by the Wildlife Trust, Lemsford Springs has become home to all kinds of wildlife. Some of which has even attracted media attention as the reserve has featured on both the BBC’s One Show and also Countryfile. One of the reserves star attractions is the Green Sandpiper. This species is present most of the year on the reserve apart from when it goes off to breed in Scandinavia from April to June. It nests in trees using old thrush nests and the males stay to raise the young once they hatch. This species is attracted to Lemsford by the high concentrations of fresh water shrimp found in the watercress channel now known as the lagoon. Just one Sandpiper is capable of eating over 8000 shrimp per day and at peak times this fairly small lagoon plays host to up to 15 Green Sands. Most of the Green Sandpipers which visit the reserve are colour ringed on site which allows us to identify individuals and get to know their behaviour. Being a regular to the reserve spending literally hundreds of hours of my life watching Green Sandpipers I really got to know particular birds and became quite attached. Hearing that one has not returned from migration or was eaten by the local Sparrowhawk still upsets me a little.

At Lemsford Springs we are still getting to know more and more about our Sandpipers as we have become the first reserve to ever to attach geolocators to this species. We are trying to find out more about the breeding location of our British wintering Green Sands. These tiny tags record the hours of daylight and light intensity levels which can be processed to give a longitude and latitude allowing us to roughly locate where a bird has been. The issue with these tags (as well as being expensive) is the fact that once a tag has been put on a bird, in order to gain any data, the tag must be retrieved off the bird again. Elsewhere this would seem almost impossible however due to the colour ringing of the Sandpipers previously we have now know that many individual birds reliably return from their breeding grounds to spend the winter on the reserve. The only problem now is catching them. Believe me, they are smart. Some of our Green Sands have got used to being caught in the mist nets and now instead of flying along the lagoon (to be inevitably caught in the trap) they fly straight upwards to avoid them. The Wildlife Trust then turned to spring traps to catch them. So far we have retrieved the tag off just one bird using this method but what it revealed is truly spectacular. This bird flew from Lemsford Springs to its breeding grounds in Finland in just 48 hours without stopping! However this is just scratching the surface into what new research methods can reveal about this fairly secretive bird. These are exciting times. 

Green Sandpipers aside, Lemsford Springs has a lot more to offer. In the winter this reserve is one of the best birding spots in the county. The secret of the springs is that the water here never freezes no matter how cold it gets. During particularly cold winters most of the local lakes and pools freeze over and the ground becomes impenetrable to most birds making feeding very difficult. However at Lemsford the water keeps flowing as it remains at a constant temperature having recently risen from the underground springs. This means birds can still feed here. This refuge attracts both Common Snipe and Jack Snipe in some numbers, even a Bittern has been attracted to the tiny reed bed here to feed in the unfrozen water. This reed bed usually hosts a pair of Water Rail too. Little Egret are also regulars. The lagoon water is also very important for birds to drink when all other sources are frozen. Brambling, Siskin, Lesser and Mealy Redpoll can all be seen here in winter both on the feeders in the wardens garden and also coming down to the lagoon edges to drink. In history during very cold winters the lagoon has attracted all kinds of surprises, Dipper being one of them. This was an extremely good record for the county.

Summer is usually a quiet time for Lemsford Springs. A few resident birds remain to breed including Kingfishers, Grey Wagtails and Green Woodpeckers. Many common warbler species can also be seen here including Garden Warbler, Sedge Warbler and Whitethroat. In some summers Mandarin Ducks nest here using some of the many owl boxes, providing a touch of the exotic. One of the best discoveries made by me and the warden in recent years was a Yellow Wagtail on the reserve. To most this is not an uncommon bird however this was the first recorded at Lemsford Springs for 50 years so not a bad find. After all, due to the reserve's location, it is not the sort of place to go looking for rarities. The rarest bird recorded here was probably Night Heron and this was many, many years before the reserve became my patch. I love Lemsford for its resident wildlife. Having read all this it may seem unsurprising to you all that my favourite bird is undoubtedly Green Sandpiper (the bird that I have probably put the most hours in watching during my teenage years). 

Apart from the birds, the reserve also has some other extraordinary wildlife including Britain’s only poisonous mammal, the Water Shrew. This amazing little shrimp killer is rarely seen but Lemsford Springs holds a healthy population. I have been lucky enough to have had a few encounters with them. Both Muntjac Deer and Fox are also regular mammal species on the reserve. A wide variety of invertebrates can also be found here in summer including many common butterflies such as Ringlet and Large Skipper.

However it is without question that the success of the wildlife is undoubtedly because of the fantastic management here by local volunteers and the warden. On the first Sunday of every month a work party is held (without fail, whatever the weather) where a group of keen and enthusiastic people turn up from the local area to help with the practical conservation needed to keep the area fantastic for wildlife. It is a huge job clearing the lagoon for the winter of all the watercress that has grown up during the summer, as well as coppicing all the crack willows growing around the lagoon edges, plus general reserve maintenance. The atmosphere during this work parties is brilliant as everyone just has fun doing whatever job needs doing and know what an amazing impact their work is having on the local wildlife. Without these people the wildlife simply wouldn’t be there which is what makes Lemsford Springs such an incredible and special reserve. To those volunteers I say thank you! Who knows, maybe one day another kid will visit the reserve, become inspired and develop a passion for wildlife like I have from this remarkable gem in the crown of Hertfordshire Birding. I continue to return to Lemsford as often as possible when I am back in the county.

Also, if you do come across any colour ringed Green Sandpipers on your local patch I would love to hear from you, after all there is a pretty strong chance they are from Lemsford Springs. Thank you!

-Drew Lyness
Drew has had a real passion for nature since he can remember and he is now 20 years old. His birding really developed when he moved to Hertfordshire in 2005 and discovered his patch Lemsford Springs. During 2013 he worked for RSPB in Dorset (Arne and Radipole) and later that year he moved to Norfolk. He is now experiencing the birding delights the county has to offer. He is a student at the University of East Anglia studying Ecology, at which he is now the president of the conservation and wildlife society. Birding aside, his other hobbies include squash and roller-skating. He also used to play the steel pans, "the world’s most awesome musical instrument", as part of a pan band.

1 comment:

  1. Nice, informative, article - brings back memories of my 'courting' days! My, then girlfriend, then wife and eventually ex-wife! used to visit LS regularly invetably departing with some freshly picked watercress. Green Sands well into double figures exceeding 30 birds IIRC. I also found a Spotted Crake one late August (in the days before bird alerts, i just left a note in the hide! I too moved to Norfolk to work for the National Trust as Summer Warden for a couple of seasons on Blakeney Point (breeding Kentish Plover and 2nd record of Lesser Crested Tern amongst many memories). I am now domiciled in my native habitat of the West Midlands an even more land-locked and bird-denuded area than Herts.....

    Laurie -