MGLG - 1997 Annual Report

In this fifth report of the Moor Green Lakes Group, which covers the period from January to December 1997 for wildlife observations and the period from spring 1997 to spring 1998 for reserve management activities, more emphasis has peen placed on providing information about the nature and outcome of the work of the Group. For those not familiar with the reserve a profile is provided at Appendix A and there is a map at Appendix G.

While overall management of the reserve is under the control of a Steering Group (for details see Appendix A) practical day to day management and the collection, recording, assessment and dissemination of information about the reserve is undertaken by the Moor Green Lakes Group, which now has a membership of over 290. The Group’s Committee Members are listed in Appendix F. If you are not a member but would like to join the Group there is an application form at the end of this report.

Our main objectives remain unchanged: to improve the reserve for wildlife, record and monitor that wildlife and enhance the facilities of the reserve for members of the Group and other visitors. In this last category a second hide, provided by Hall Aggregates (South East) Ltd, has been erected at the eastern end of Grove Lake and was formally opened on 24th September, 1997 as part of an Open Day at the Eversley complex. Access to this hide is shortest from the Rambler’s Car Park at the entrance to the Horseshoe Lake Water Sports Centre off Mill Lane. The Grove Lake hide has not been modified for wheelchair use and it will not be open to the public except when is use by members of the Moor Green Lakes Group. Access for members will be on the same basis as for the Colebrook Lakes hide.

Locating the hide on Grove Lake is intended to provide the opportunity for some alternative viewing to that available from the Colebrook Lakes hide. In winter it should be possible to obtain good views of the Goosander which use Grove Lake for roosting. A feeding station has also been set up alongside the hide to attract additional species and provide added interest for younger members using the hide. In due course the scrape in front of the new hide will be extended by Hall Aggregates (SE) Ltd.

In Chapter 2 Steve Bailey describes the valuable and considerable work which has been undertaken on the reserve by volunteers during the last year. On behalf of the Group I would like to thank all those members who have helped us in this important task, and in particular members of the Blackwater Valley Recreation and Countryside Management Service and of the Farnborough College of Technology. There is still much to do and if you have not yet joined one of our work parties we hope you will be able to do so during the coming year, even if only for an hour. With a reserve of this size there is a great deal to be done and without the help of volunteers there would soon be a decline in the diversity of wildlife on the reserve.

I would also like to take this opportunity of expressing our thanks to Steve Bailey and to Nick Mutch for the considerable amount of time and effort they have devoted to the running of the reserve over the past year.

A start has been made on a systematic botanical survey of the reserve using random sample plots. This has been organised by Delphine Hoyle who describes in Chapter 5 the process used and the first results. If you have visited the reserve you will almost certainly have noticed that a number of nest boxes have been put up. This has been organised by Kevin Briggs who provides in Chapter 4 information on the use to which these were put during the 1997 breeding season. Their exploitation by Mandarin Ducks has been particularly successful.

We are also able for the first time in Chapter 10 to include some information on two invertebrates, Hoverflles and Spiders, which have not featured before in our reports. Since our last report there has been a change in the recorder for dragonflies, Ken Crick having taken over from Phil Young. The checklist of plants which appeared at Appendix C in the 1995-96 Report has not been repeated and reference should be made to that Report for details.

The ornithological importance of the reserve continues to grow and lan Browns account of the birds seen during 1997 forms a major part of the Annual Report and our thanks are due to Ian for the time and trouble he has taken to produce such a comprehensive account.

Use has been made by both Ian Brown and Chris Taylor, of the bird and butterfly records left by members and others who visited the hide where record sheets for this purpose are placed. This help is greatly appreciated and enables us to monitor more closely these two wildlife groups.

The 1998 Annual General Meeting of the Group, kindly hosted by Hall Aggregates (SE) Ltd., was held at Finchampstead Memorial Hall on 27th February. During the meeting members were given a progress report on reserve activities and wildlife monitoring and the formal business was followed by an illustrated talk by Frank Greenaway about bats. The subject was of significance as we are currently exploring the possibility of establishing on the reserve a bat cave.

During the year there have been two meetings of the Steering Group, in October and April, at which the Group has reported on its activities over the past year and outlined its plans for the coming year. With the introduction of the new unitary authorities in Berkshire from 1st April 1998 the County Council is no longer represented on the Steering Group and instead both Wokingham District Council and Bracknell Forest Borough Council have been invited to send representatives.

For further information about the Group and its activities the contact is either Brendan McCartney, telephone 0118-9732393 or the Blackwater Valley Recreation and Countryside Management Service (BVRCMS), telephone 01252-331353. If any member notices something happening at the reserve which might result in damage or threaten wildlife would they please inform the BVRCMS on 01252-331 353, or Nick Mutch, telephone 01344-771400.

Information about the reserve and the Group is now also available on the Internet thanks to our Membership Secretary, Brendan McCartney, who has created on our behalf a Moor Green Web Site. An account of this, together with details of the information it provides (which includes recent wildlife sightings) is given in Chapter 12.

Finally, as you will have noticed from the front of this report, the Moor Green Lakes Group has adopted a new logo, drawn by Robert Gilmor and featuring Goosanders for which the reserve is now nationally important for the number which it attracts in winter. I am grateful to Brendan McCartney for reproducing the logo for use in the report as well as for formatting the report itself, and to Hall Aggregates (SE) Ltd for copying the report for circulation.

This has been a very active period for conservation work on the reserve with many different people involved. The highlight of the year’s conservation work was the erection of the reserves second hide and the construction of an associated scrape.

Group members have carried out a Sunday task each month from September to March. Students from Farnborough College have carried out some practical site management tasks as part of their college course and the Tuesday group of the Blackwater Valley Conservation Volunteers have frequently worked on the site whenever jobs have been required. Members of the Yateley cub-scout group put in a day’s work towards their conservation badge.

In addition to this volunteer effort contractors were employed by Hall Aggregates (SE) Ltd to install the new hide and excavate the scrape in front of it.

Fencing was checked and repaired where necessary before the cattle were introduced.

Our new grazier, Mr Jacobs, then introduced 4 young Aberdeen Angus heifers to the site between 23 November 1997 and 8 February 1998. Initially restricted to the Colebrook Lake North paddocks the animals were later let into the land around Grove Lake.

These new arrangements have worked well and have achieved the desired effect upon the pastures.

The normal clearance programme on the islands was carried out to prevent these vital nesting and loafing areas from becoming overgrown.

The north shore of Long Island. together with patches on the north shore of Colebrook Lake North, were strimmed to create short grass areas with access points for grazing Wigeon and geese. Some brambles were cleared on Long Island to prevent encroachment across the grassy areas.

Tern Island was completely cleared to bare gravel with the plastic mulch area extended as this is proving to be an effect weed suppresser. Sandpiper and Plover islands were also worked on to create bare gravel conditions.

Grove Island is favoured by the nesting geese which seem to prefer to nest in, or adjacent to, patches of bramble but with easy access to the water. Here trees were thinned and paths and alcoves cut into the bramble.

The rafts were removed during the winter period to prevent the cormorants becoming accustomed to standing on them. They were replaced on 31 April 1998, all with fresh gravel.

Thinning of trees around the lakes continues. The aim is to restrict the trees to 2m to 3m height to attract warblers and other scrub species but not so tall as to put off the wildfowl from using the lakes.

Many willows were dug from around shores of Colebrook Lake in an attempt to keep the shoreline clear of tree growth. Elsewhere trees were either coppiced or pollarded to create a variety of structures to the scrub.

Last year’s contractors, under instructions, threw the trees they cut into the lake edge. Dead wood in water is an important habitat for many invertebrates. Unfortunately most of the trees proved to be Willow and started to grow. If allowed to mature these would have been very difficult to manage and so had to be removed - a very muddy and wet, cold and wet, smelly and wet job. Bonus points to those who helped on this task.

The Blackthorn hedge along the path from the Lower Sandhurst Road car park delights in encroaching onto the path and field edge; this was cut back.

Most cut material was used to repair and extend the dead hedge in front of the Colebrook scrape.

The trees previously planted near Colebrook hide are growing well and required various maintenance jobs such as weeding and replacing or even removing stakes and guards.

Approximately 30 bird boxes have been erected in previous years. These were all checked to reveal a good occupancy including five Mandarin nests as well as assorted tit broods.

An assortment of bat boxes is now in place. Nine were erected in Dec 1998 on the trees to the north of Grove Lake and a further 15 in the hedge along the path from the Lower Sandhurst Road car park on 31 April 98.

Contractors erected the new hide at Grove Lake. As with the first hide. a number of alterations and additions were left for volunteers to sort out including work to the side wings, narrowing of viewing slots, anti vandal measures, installation of lock plates for a combination lock and a gutter and down pipe.

A new scrape has been dug in front of the new hide. Unfortunately nobody from the site management committee could be present during digging, hence it is rather smaller than designed. The intention is to extend and improve this scrape this summer.

Viewing points were all re-cut. A five-year cutting cycle has now been established to the viewing points to maintain the views at the best spots and to use the opportunity of this necessary cutting to create a varied scrub edge structure.

The undoubted highlight of the year was the exceptional influx of Goosander in January, when a site record count of 184 birds roosted. At this time during the day in excess of 100 birds were regularly using the site. This influx was mirrored throughout the UK. Other early year records included two redhead Smew, a brief sighting of Mediterranean Gull (Jan), two relatively brief sightings of Ring Billed Gull (Jan) constituting the first records for the site and single Bittern, Red Breasted Merganser and Firecrest, all in February. Although wildfowl were present in force the numbers were slightly lower than the previous winter.

Early spring started with two Rock Pipits in mid March with other spring highlights including Sanderling. Little Stint and, unexpectedly, 2 Curlew Sandpipers, which gave obliging views to many visitors during a six day stay.

Breeding success was mixed. Redshank reared three young successfully for the first time since 1992. Lapwing (the best success in recent years) and Little Ringed Plover were both successful, but of the regular breeders Ringed Plover and Common Tern failed due to predation as in previous years. Barn Owl was again successful and a record 7 pairs of Mandarin used mainly specially erected nestboxes. The small Sand Martin colony in the new workings continued despite the loss of last years nesting bank and Grey Heron, although unsuccessful, attempted to breed for the first time.

Late summer/early autumn began with a brief visit by four Black Tailed Godwits and a Honey Buzzard. Other autumn records, all in August, included 2 Turnstone, 2 Wood Sandpipers, one of which stayed for over a week, a Spotted Redshank and an Arctic Tern. The only records of note in the late year were a Goshawk (only the second site record) and a Little Gull (both in November) and finally a single record of redhead Smew (Dec).

S.Bailey

Dr K.B.Briggs

Dr I.H.Brown

J.M.Clark

Dr M.N.Clifford

J.N.Dixon

C.R.Gent

R.J.Godden

J.Guningham

P.Hodson

Ms D.Housley

Dr D.A.Hoyle

A.C.James

B.McCartney

Mrs R.McCartney

J.N.Mutch

E.Napper

N.R.Peters

C.Proudley

Mrs M.Robbins

Mrs C.Rose

G.J.S. Rowland

M.A.Scott

D.M.Spittle

J.C.Tanner

Mrs L.D.M.Tanner

C.D.Taylor

M.Taylor

A.Twyford

l.Twyford

During the past four years nest boxes have been placed around the holes on the hedgerow trees. By 1997 there were 23 boxes and it was decided to monitor them for breeding success and to ring as many of the young as possible.

The large boxes erected for the Mandarin Ducks were very successful with five boxes being used clutches of 2, 14, 9, 8, 8) and two clutches of 10 were also found in natural sites. Five clutches hatched and produced 45 ducklings. Did you see any? The larger boxes also produced a brood of 2 Tawny Owls, 2 Little Owls and two sequential broods of 2 Stock Doves.

The smaller boxes had 8 clutches of Blue Tit eggs. One was predated by a Great Spotted Woodpecker but the other seven pairs produced 59 young. Five pairs of Great Tit were also found but only four successfully fledged young (total 34). The Tits had all fledged their young by May 15 (an early date) and so avoided the fate of many other pairs fledging in the latter half of the month or in June when the cold, wet, weather resulted in many moribund broods.

The occupancy rate of the boxes was high (85%) so more were erected in the winter of 1997/98 to bring the total to 33.

For a number of years (excluding 1996) plant surveys were carried Out on the species present around the Colebrook lakes.

For 1997 it was felt that it would be more useful to undertake a quantitative survey of the grazed areas, which if repeated regularly, would give a measure of change in the plant communities present. The method used was based on National Vegetational Classification (NVC) Methodology.

10 random samples (1x1 metre) were surveyed on 17th July, 1997, 5 on the north shore and 5 on the west shore of Colebrook Lake North. In each of the samples the species present were identified and quantified on the abundance present -

The results of the quantitative survey are shown below in Table A (flowering plants) and Table B (grasses). For each species the frequency with which they occurred in each of the two areas sampled is given followed in brackets by their level of abundance e.g. Agrimony occurred in only one of the sample 1x1 metre plots, with just a few individual specimens, while Oxeye Daisy occurred in all ten plots, its abundance varying from a little under 4% of a plot to 76-90% of a plot.

While it is too early to draw many conclusions from this first quantitative survey it is interesting to note that only 5 of the original species in the sown meadow mix were not found. This shows a remarkably good success rate. The species not found were Ranunculus acris, Silaum silaus, Sanguisorba officinalis, Taraxacum officinalis (a little surprisingly) and Vicia sativa.

Two of the species found - Sanguisorba minor and Anthyllis vulneraria - are not naturally found in the Blackwater Valley so might have been introduced accidentally in the seed mixture.

There also appears to be a slight difference between the two areas since Sanguisorba minor and Geranium pratente, which prefer more calcareous conditions, were only found on the north side.

Thanks are due to Steve Bailey, Richard Bissett, Daisy Marshall and Greg Nuthall for their help with this survey.

During the period November 1996 to April 1997 members of the Moor Green Lakes Group assisted a student from Farnborough College of Technology in her study of small mammal populations at Moor Green Lakes. Four sites around Colebrook Lakes North and South were selected and trapping was carried out on three occasions at each site.

Trapping was executed in accordance with the Mammal Society Guide entitled “Live Trapping of Small Mammals” using the Longworth trap - the standard equipment used since the 1940’s for such studies. The trap has two parts - a tunnel which contains the door tipping mechanism, and a nest box which attaches to the tunnel when the trap is set. The nest box provides space for food and bedding to ensure the welfare of the trapped animal.

Each trapping session was carried out over four successive nights - on the first two, food was placed in and outside the trap but the door was fixed open. This procedure, known as pre-baiting, allowed mammals to locate and become familiar with the traps as new features in their home range. On the final two nights the traps were set and each trap was visited at dawn the next morning. The mammals caught were identified, sexed, measured and weighed before being released.

In all, five species were located, given below in descending order of abundance:

Whereas Wood Mice were plentiful, only two Common Shrews and one Pygmy Shrew were trapped. There was an even distribution of Bank Vole and Field Vole. However, population levels peaked in Nov/Dec and declined throughout the rest of the survey. This was considered to arise from several factors: sufficient availability of food during the autumn and early winter: immigration from adjacent area being grazed by cattle during Nov/Dec; good ground cover (tussocky grass. etc.) before onset of winter. Wood Mice populations suffered from winter mortality greater than any other species.

The greatest diversity of species and highest numbers of individuals were recorded in the wooded area south of the Colebrook Lake bird-watching hide. This is adjacent to the cultivated land west of the footpath, which may have had a bearing on the population - i.e. immigration following harvest. However, this habitat was clearly preferred by the three main species as compared with the “open grassland” habitats investigated.

The ratio of males to females was always unequal - males being the more abundant - and it is considered to result from males seeking a suitable mate over an extended home range.

Predators noted during the survey were Red Fox - Vulpes vulpes, Kestrel - Falco tinnunculus, and Barn Owl – Tyto alba.

The survey concluded that Moor Green Lakes currently provides a suitable environment to support small mammals (and therefore their predators) and recommends management techniques to maintain the favoured habitat of scrub and tussocky grassland. Clearly the Group has benefited from the information obtained from this relatively limited but valuable survey and will give heed to the recommendation it contains.

After attending a short course on woodland management in the early spring, which covered the rudiments of species surveying, it was decided to try and put the lessons learnt into practice.

The order Odonata was selected and Moor Green, the River Blackwater and adjacent lakes became the focus of activity.