FIELD NOTES
FEBRUARY 2003 continued....
SURVEYS
Changing Partridge Populations
In 1996 we suddenly realised that both Red-legged Partridges Alectoris rufa and Grey Partridges Perdix perdix had declined, even disappeared, from sites around our home area where we had regularly observed them for many years. Since then we have recorded all coveys seen by us in the county and, more particularly, have carried out regular autumn to spring searches and counts in the rural tract north of the Mimram Valley bounded by the A1(M), B1000, and A602 roads.
We soon found that Partridges are most easily located in the early morning and late afternoon when they emerge from cover to feed. We also found that they tend to remain loyal to a small group of fields, usually autumn sown cereals, and adjacent cover. As a result they are relatively easy to relocate.
In the autumn of 1999 we failed to find Red-legged Partridges at a significant number of locations where we had found them in previous years. The number of coveys found in our study area had decreased from 27 to 21. Significantly average autumn covey sizes had also decreased from 6.2 to 4.9. These figures suggested a sudden further decline in local populations. In consequence we published an appeal for information about this species in Hertfordshire (Herts Bird Club Bulletin: 209. March. 2000) and received a number of helpful responses.
Since then the decline in our study area has continued. In the autumn of 2002 we only found 14 coveys comprising an average of 4.3 birds. Some, in areas where we had previously found coveys of up to nine birds, comprised as few as two or three birds. The limited amount of data we have collected is suggestive of lower breeding success.
The Grey Partridge is now a very uncommon bird in our study area.
Our simple study continues. Red-legged Partridges are easily identified and often easily seen, e.g. from a car. It is important that we receive records of all Red-legged Partridges seen in the county and not just those for unusually large coveys. For each observation the information we need is Date and Time, Location preferably including a six digit grid reference, Number Seen, Activity i.e. resting or feeding, and Habitat, e.g. autumn sown cereals, grassland, woodland path. Any evidence of breeding and releases is also needed.
Tom and Janet Gladwin
99, Warren Way
Digswell
Welwyn
Herts AL6 0DL.
Tel: 01438 714700.
Email: tomandjanet.gladwin@btinternet.com
THE HERTS WILDLIFE CALENDAR
The Herts Wildlife Calendar for the Year 2003 and a schedule of Moth Trapping nights is attached. This is a rolling programme and can be added to at any time. So, if any of you run specialist groups and wish your meetings or activities to be advertised more widely, let me know and I will add them to the list. It is hoped to enclose the latest programme with each mail-shot.
RECORDERS
As mentioned previously in the Newsletter, there have been some changes to our Recorders. Details can be found in the County Recorders Page.
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