Worcestershire Record No. 24 April 2008 p. 4

BIRD ATLAS 2007-2011

Harry Green

BTO Regional Representative Worcestershire

Field work for the New Atlas has got off to a flying start. The use of the internet to send in records has been a great success with huge numbers of records already entered in the BTO computers. Entry of paper records from last winter is already in hand. Additionally records from the BirdTrack system are now also used for the Atlas. As explained in my article in November 2007 Worcestershire Record the data is collected in two ways: Timed Tetrad Visits (TTVs) and Roving Records. The former will be used to prepare map as of population density for each species and the both the TTVs and Roving Records contribute to national distribution maps at 10x10 km grid square resolution. In Worcestershire coverage of about 40% of tetrads has been promised for last winter and this summer which as excellent start. Regarding the winter surveys TTVs covered last winter are not surveyed again (the aim is coverage once in the four year Atlas period) so hopefully observers can move on to new tetrads. Similarly summer surveys are only done once.

If you would like to take part in gathering data for the Atlas please contact me or you can go to the Atlas web site where you will find full information on registering tetrads in your name which is then passed to me so I can collate county coverage. Results can be entered directly on the web site (which saves a lot of time an d money) or on paper forms which I supply, covering both TTVs and Roving Records.

Reprinted below is part of the information printed in the November 2007 Worcestershire Record giving more information.


Fieldwork for the next BTO/BirdWatch Ireland/Scottish Ornithologists Club Atlas started at the beginning of November 2007 and will continue for four years: 2007-2011. The data is being collected and collated at the BTO. The last Atlas of Breeding Birds was based on fieldwork 1988-1991, and the first on fieldwork between 1968 and 1972. Data for an Atlas of Winter Birds was collected between 1st November 1981 and the end Feb 1984. Between them these Atlases have charted some notable changes in the distribution and numbers of birds occurring in Great Britain and Ireland. The current Atlas is the first attempt to combine fieldwork for both summer breeding birds and wintering birds during the same period of years.

The surveys, both winter and summer, are in two main parts. One is to find all the species using 10x10km square in the British Isles during the survey periods and in summer to determine breeding status. The second is to make rough estimates of the numbers of each species based on sample counts made during Timed Tetrad Visits (TTVs). Tetrads are 2x2km squares and there are 25 in each 10x10km square. The aim is to survey a minimum of eight tetrads, winter and summer, in every 10x10 km square (there are obvious exceptions in, for example, coastal squares).

The field work therefore consists of collecting Roving Records throughout the four years of the survey to build up the 10x10km square lists, and undertaking TTVs. Once the TTVs have been made, winter and summer, recording for that tetrad is complete and is not repeated. Hopefully observers will move on to new tetrads. Roving Records for any tetrad through the Atlas period are of course important.

Early and late visits are required both winter and summer to complete coverage of a tetrad. The two winter periods are from 1st November to 31st December, and from 1st January to last day of February. The two summer visits are between 1st April and 31st May, and between 1st June and 31st July. It is best if the two visits in both periods are at least two weeks apart.

Unlike the previous Atlases the new one is making very great use of the internet enabling observers to obtain information and to submit results on-line. This is a very great step forward enabling millions of records to processed very rapidly. Observers can of course send in records on paper and these will be entered on to the database at BTO. The findings of other BTO surveys are also being incorporated into the Atlas database. These include, for example, Garden Bird Watch, the Breeding Birds Survey, and BirdTrack, and data from other specialist surveys.

If you would like to help with the Atlas in Worcestershire please contact me. An easy way to get involved is via the web site www.birdatlas.net. You can reach the same point via the BTO web site. From the site you can view and download information. You can also select a tetrad as yet uncovered by anyone else and register your interest. This information is sent to me and I can then allocate the tetrad to you and send you the relevant paperwork. After your fieldwork you can easily enter your records on-line or if you wish send them to me on the forms provided. The paperwork explains very clearly the details and methods of the survey.

In Worcestershire I cover 18 10x10km squares. Some of these overlap neighbouring counties and I cover those areas as well. Similarly adjacent counties cover some parts of Worcestershire – the BTO works on square boundaries for these surveys! That gives a total of 450 tetrads for Worcestershire.

It is certainly never too late to start collecting Roving Records which can be collected anywhere at any time, and entered on to the web site or on the paper forms. Where possible these records are designated to a tetrad and they need to be dated.

I think the results from this Atlas will be amazing! The use of the internet and modern computing will enable processing of very large numbers of records very quickly. The publication date is currently scheduled for 2014 – the year of my 80th birthday! I can’t help wondering if I shall be around to see it! It is also pretty sobering thought to realise I have been personally involved in organising, collecting, and collating data from Worcestershire for this and all the previous Atlases.

Please contact me for further information.harrygreen_worcs@yahoo.co.uk, or 01386 710377 or Windy Ridge, Pershore Road, Little Comberton, Pershore, Worcs., WR10 3EW.

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