Survey – WHBBS
Wealden Heaths Breeding Bird Survey (West Sussex)
A mixed bag of weather (as usual) was evident through the survey season. My notes show some clear days at 11c in mid-February rising on the 29th to 20c. Overall spring temperatures were slightly higher than average but a very wet period in March (the UK’s 5th wettest March on record) undoubtedly affected some early breeders. April commenced rather chilly but became warmer with temperatures in the 20c’s at the end. Early May returned to cool but warmed up during the month and June into July saw daytime temperatures well above average. Most of July was extremely dry (UK receiving 71% of average rainfall).
For our five priority species, Nightjar, Woodlark, Tree Pipit, Stonechat and Dartford Warbler it was a reasonably successful year with all showing a slight increase over 2018 figures. Particularly encouraging was Tree Pipit and although it was only a small increase from 16 in 2018 to 19 in 2019 this hopefully will be a reversal of the recent declining trend; however the national picture is that the population is contracting in south- east England, occurring at its greatest abundance in Wales, northern England and Scotland. Black Down with a count of seven remains our most successful heath. Also encouraging is the continued resilience of the Nightjar and Woodlark populations throughout the 22 year survey period. Perhaps indicating that despite greater leisure activity pressure (especially as our heaths are now in the South Downs National Park) ongoing management ensures favourable habitat conditions for breeding. Likewise Stonechat and Dartford Warbler continue to increase their numbers recovering from the terrible winter of 2009/10, the latter however is only a slow increase, perhaps a good summer breeding period will provide the impetus for a return to the upward surge in numbers seen during the early years of this survey . The increase 2018 to 2019 was 21-34.
It will be noted from the graphs (click here) that the only declines this year were from three of our most successful species – Green and Great Spotted Woodpeckers and Stock Dove. however I doubt this is statistically meaningful but obviously future surveys will check for any adverse trend. Redstart, apart from the outstanding year of 2015, remains consistently, since 2011, in the 10-15 range. To encourage breeding a nest box scheme is being considered at Lynchmere/Stanley. Perhaps this could be expanded into other heaths particularly those situated on the high ridge area.
Whitethroat retains a steady population as do Linnet and Yellow Hammer, the former (Linnet) with an increase 44-52. Woodcock remains a difficult species to survey unless roding birds “meet up” but the estimate of 14 is within the 10-15 range that has been reported since 2011.
The remaining species within the survey have either provided nil results or their numbers are too low to warrant graphs. However, it was pleasing to have three Crossbill reported after a negative 2018. Black Down and Lynchmere appear to be the most reliable sites for this species when it does stay to breed, followed by Lavington and Ambersham/Heyshott.
Reports from surveyors reported on-going management but the principle concern, as noted last year is of disturbance. Dog walking or rather free-range dogs being the main culprits particularly where dog-sitters exercise a “pack”. As I reiterate each year our Wealden Heaths are very small, dislocated and fragile and it is only through careful and sensitive management (including education of the users) that we can ensure their future sustainability.
I think it worth noting that these results are not just recorded by the SOS but relevant details are sent to the owners/land managers/experts to provide information for future management.
Background to the survey
Originally the Wealden Heaths and Thames Basin Breeding Bird Survey was set up in 1997 as a collaboration between four county ornithological societies to monitor the important heathlands of West Sussex, Surrey, Hampshire and Berkshire. These included some of the Wealden heaths, designated as a Special Protection Area (SPA) in 1994 (Phase I) and 1998 (Phase II), and the Thames Basin heaths, designated as an SPA in 2005. There are no immediate plans by the statutory authority to implement a Phase III to include the West Sussex group of Wealden heaths. Nevertheless, the Wealden Heaths Breeding Bird Survey (West Sussex) is continuing with the objectives of providing data to assist in management decisions and to enable results to be measured thereafter, to provide a long run of data to help protect the sites from damaging developments either within or adjacent to them, and to ensure that results are retained in the Sussex Ornithological Society database.
Currently fourteen heaths (Iping & Stedham are recorded individually) are regularly monitored and include recently Graffham, Midhurst and Broad Halfpenny. West Heath was formerly monitored but is now largely a sand extraction site, however it is hoped that when the work ceases it will be returned to an actively managed heathland site.
Twenty-one bird species perceived to be specialists of the habitat or typical users were chosen as the subjects of the survey and of these Nightjar Caprimulgus europaeus, Woodlark Lullulu arborea, Dartford Warbler Sylvia undata, Tree Pipit Anthus trivialis and Stonechat Saxicola torquata were considered priority species.
Although these five species are our main quarry the recording form enables us to monitor the remaining species which include Yellow Hammer, Redstart, Linnet and other typical heathland birds (sadly Turtle Dove has not been recorded for many years). A brief schedule of the results are published in the Sussex Bird Report annually.
How can you help?
Although we have surveyors for the sites currently there often problems and we have to ask urgently for a new surveyor or a temporary surveyor is needed to cover a heath due to illness etc. If you would like to help then please contact the coordinator Alan Perry for further information (see below for contact details).
The format of the survey is as follows :
The Survey starts in mid- February, (to find the Woodlarks taking up their territories) and carries on until late June. We try to cover the individual sites entirely on four occasions, including one early visit as mentioned, and two visits (more if you have the inclination and the time), about two weeks apart during May when song activity is at its peak. There will be at least one evening visit (preferably two) in May and/or June to count Nightjar.
With the data collected we are able to estimate the total number of breeding pairs/territorial males of each species and assess the success or otherwise of these birds over a long time frame.
The heathlands we cover are as follows:
Lynchmere & Stanley Commons
Ambersham & Heyshott Commons
Lavington & Duncton Commons
Coates & Lords Piece
Recent additions: Graffham Common, Broad Halfpenny.
Currently not viable – West Heath.
Currently vacant Hesworth Common. A small village-owned heath.
For more information or if you wish to volunteer please contact the organiser Alan Perry on 01798 344417 or by email firstname.lastname@example.org
A paper of the survey 1998-2015 was published in the Sussex Bird Report 2016 entitled “Wealden Heaths Breeding Bird Survey (West Sussex) 1998-2015”. The paper included heathland background information, site descriptions and notes on wintering birds.
An extended version of this paper including a preface, site maps, management issues and bird photographs, taken mainly by Sussex birders, is available by email from Alan Perry apply email@example.com.
The survey is ongoing