On Nov 4, 9:37*pm, wrote:
Is it important that the gardeners' counts of birds is accurate or
not, for the British Trust for Ornothology's "Garden Bird Watch"
scheme?

Or is this just another charity survey to catch potential supporters
and donors by making them feel useful?

All sounds a bit random and uncontrolled to me. I don't see how they
can tell anything about numbers. Distribution, maybe. Depending on
how accurately people identify the birds.