Monitoring work is very important.  It advances our knowledge of birds, provides data which can be used in their conservation and, moreover, is thoroughly enjoyable.  Over the years GOS members have participated in over 50 surveys, both national and local, many of which are ongoing.  Do read through the list below and think seriously about taking part in one.

In addition to these surveys, a number of targeted species (Dipper, Grey Wagtail, Nightjar, Red Kite, Goshawk, Wood Warbler, Hawfinch and more) are monitored by GOS members.


Current and ongoing surveys

The Breeding Bird Survey

The BTO/JNCC/RSPB Breeding Bird Survey (BBS) is the main scheme for monitoring the population changes of the UK’s common breeding birds.  It is a national volunteer project aimed at keeping track of changes in the breeding populations of widespread bird species in the UK.  Wild bird populations are an important indicator of the health of the countryside, and knowing to what extent bird populations are increasing or decreasing is fundamental to bird conservation.

BBS was designed to be easy!  The survey only requires two visits during the breeding season, and noting down the birds along a 2km fixed route.  A typical visit takes less than two hours, and perhaps another hour for the online data-entry – for the two visits a total of probably no more than six hours per year.

So if you can identify the majority of common birds by song and call, then please think about whether you could do a BBS square. Every active birder should be doing at least one BBS!

GOS has 74 squares, most of which are covered, but there’s inevitably a regular turnover of volunteers as individuals’ circumstances change, and there will always be a few vacant squares requiring new observers.  These currently number 21 so if you feel like taking part in this survey you’ll have a choice of locations.

See for more information.  If you can help, please contact Richard Clarke at to see which squares are available.


Waterways Breeding Bird Survey

The WBBS, run by the BTO, is similar to the Breeding Bird Survey (BBS) but the route is along a waterway rather than being in straight lines across a square plot.  If you can identify most common birds by song and call, then this survey is even easier than BBS!  What could be more enjoyable than walking along a canal or river for between 500m and a maximum of 5km, noting the birds you see and hear? Just two counting visits are needed between April and June, one before and one after mid-May.

WBBS covers all bird and mammal species but is especially valuable for monitoring the population trends of specialist animals of linear waters, such as Goosander, Common Sandpiper, Kingfisher, Dipper, water vole, otter and American mink.

See for more information. If you’d like to help, please contact Richard Clarke at to find out where transects are available.


The Wetlands Bird Survey (WeBS)

WeBS involves nationally coordinated monthly counts of non-breeding waterbirds on all suitable habitats. WeBS has three major objectives:

  • to assess the size of non-breeding waterbird populations in the UK;
  • to assess trends in their numbers and distribution;
  • to assess the importance of individual sites for waterbirds.

WeBS data have formed crucial components of many environmental impact assessments in relation to major planning proposals.

What does WeBS counting involve?

WeBS covers inland water bodies (lakes, reservoirs & canals), rivers and estuarine coasts.  A WeBS counter is registered to count all waterbirds at a particular site (or sites) on a regular monthly basis.  The minimum commitment is to count in the three mid-winter months of Dec-Feb, but the ideal is to count in every month throughout the year.  Counts are scheduled for a prescribed Sunday each month.  You can choose an adjacent day if the Sunday is not possible, e.g. if the weather is too bad.  If you are ill or on holiday and a count is missed, don’t worry – such things are inevitable!  Your count data are submitted online to BTO.

See the British Trust for Ornithology Wetland Bird Survey pages for more information. If you can help, please contact Richard Clarke at (inland waters) or Kevin Dupé at (Severn estuary, Wales) to find out more, including details of the sites where a surveyor is needed.

Heronries Census

This BTO survey aims to count as many heronries as possible each year and to ensure that newly established sites are quickly discovered. The main species covered is Grey Heron but Little Egret is included, as are rarer species of colonial waterbirds such as Cattle Egrets, which nested in the UK for the first time in 2008.  Click here for more information.

As part of the national census, GOS plans to revisit all known/historical heronries in the county during 2019.  Contact: Richard Clarke at