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The countdown is on - fieldwork starts 1st November 2007 Fieldwork will span 4 winters and 4 breeding seasons, starting in November 2007, during which we will cumulatively survey the whole of Britain and Ireland. To fulfil these objectives there are two complementary fieldwork methods which offer something for everyone. Roving Records - whatever you see, whenever, wherever
Timed Tetrad Visits - dedicated counts in specified tetradsTimed Tetrad Visits (TTVs) are principally concerned with discovering the broad patterns of relative abundance. Basically a TTV involves walking around a tetrad, birdwatching for 1 or 2 hours and recording everything you see and hear.
Timed Tetrad Visit field methods These brief instructions apply to either winter or breeding season. Ideally the same tetrad would be done in both seasons. You need to make two visits in a season, one early and one late. In winter this means the first visit in November/December and the second in January/February. In the breeding season this means the first in April/May and the second in June/July. Once you have made two visits in the winter and two visits in the breeding season, then that tetrad is done. A tetrad should not be covered in all four years of the Atlas. Each visit must last a minimum of 1 hour, or optionally 2 hours. Whether you spend 1 hour or 2 hours, during this timed part of the visit you should aim to survey all the major habitat types present in the tetrad and count all individuals of all species you see or hear. You can briefly 'stop the clock' if you encounter large flocks or especially dense concentrations of birds that slow your progress. Record any evidence of breeding you notice whilst surveying. At the end of your 1 or 2 hours you can opt to continue listing (i.e. just ticking off) additional species, or returning to particular areas to search for missed species or to try and confirm breeding. After your two visits you
can optionally produce your own estimate of how many individuals
of each species was present in the whole tetrad. So bearing in mind
how much of the square you visited you might be able to very approximately
extrapolate the numbers you encountered on your route to the number
in the whole tetrad. We are only looking for very approximate numbers,
to the nearest 1 for numbers less than 10, to the nearest 10 for
numbers less than 100, to the nearest 100 for numbers less than
1000 etc. For some species and habitats this will be very easy.
If you visited the only lake in the square and saw 6 tufted ducks
your tetrad estimate will be just 6. If on the other hand you reckon
you visited half of the woodland and encountered 14 Blue Tits, your
extrapolated tetrad estimate might be 30. Though these numbers are
by definition pretty crude, other studies have found them to be
very useful when taken with everyone else's across the whole country.
But they are optional, so if you don't feel confident giving them
don't worry.
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Tetrads
are 2km × 2km squares and labelled A to Z within each 10-km
square (see image, right). TTVs do not aim to produce a
complete species list for the tetrad, but a sample of what one can
find during a pair of visits in winter and/or summer. We aim to
cumulatively cover at least 8 tetrads in every 10-km square in Britain
and Ireland during winter and summer. You can take on one or as
many tetrads as you wish. This is a great opportunity to visit those
hidden corners of the landscape and find new birds. If you are interested
in taking on a tetrad (or more..) please contact your Atlas Regional
Organiser (
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