Standard BTO Symbols for Bird Activities

Rather than use the standard BTO code for Willow Tit (WT) when mapping the location of contacts, please use the terms A1, B1, etc., to denote records from the first visit and A2, B2, etc., from the second visit.

A1, 2A2 Willow Tit sight records with age, or number of birds if appropriate. A1P   indicates one pair;  2AP means two pairs together.
A1 A calling Willow Tit.
A1 A Willow Tit repeatedly giving alarm calls or other vocalisations (not song) thought to have strong territorial significance.
A1 A singing Willow Tit.
A1   B1 An aggressive encounter between Willow Tits.
*A1 An occupied nest of Willow Tits; do not mark unoccupied nests, which are of no territorial significance by themselves.
A1 mat Willow Tit carrying nesting material.
A1 food Willow Tit carrying food (during courtship display).
Willow Tit movements can be shown as follows:
— A1 — A calling Willow Tit in flight (seen only in flight).
A1 —> A singing Willow Tit perched then flying away (not seen to land).
—> A1 A Willow Tit flying in and landing (first seen in flight).
The following conventions indicate when registrations relate to different birds, and when to the same bird:
A1 —> A1 A Willow Tit moving between two perches.  The solid line indicates it was definitely the same bird.
 A1 — B1 Two Willow Tits in song at the same time, i.e. definitely different birds.  The dotted line indicates a simultaneous registration and is of great value in separating territories.
A1 — A1 The solid line indicates that the registrations refer to the same bird.
A  — ? — A A question-marked solid line indicates that the registrations probably relate to the same bird.
A          A No line joining the registration indicates that the birds are probably different but depending on the pattern of other registrations they may be treated as if only one bird was involved.