In 1998 it was decided that the daily census data held by the individual observatories was totally inaccessible in its present form - paper, hand-written log books going back as many as 40 or 50 years.  However, before we could progress to looking for sponsorship to get the data computerised we had to see if the data could be used for population monitoring.

Although there is plenty of evidence to suggest that it can, and people who had been involved in the gathering of the data had a gut felling that they should, we needed to prove it before going any further.  To this end we arranged for the extraction of 10 years worth of data for 8 species .  The species chosen were selected because their populations showed distinct changes using the British Trust for Ornithology's current monitoring tools - Common Bird Census (CBC) and Constant Effort Sites (CES).

The data were not altered in any way, other than changing the count averages to log form, the sample graphs below show these plots against those from CBC and CES.  The results speak for themselves.

Indices for Sparrowhawk Accipiter nisus

Indices for Willow Warbler Phylloscopus trochilus

Indices for Whitethroat Sylvia communis

Although the data may need further work before it can be used in scientific arguments by bodies such as the BTO and RSPB it is clear that it offers the possibility of being able to monitor populations back much further than currently possible using methods such as CBC and CES.

We now need to find the funding to computerise all the data, no small task with 15 accredited observatories and 2 other sites with very long runs of data.  Work is underway investigating possibilities.