Start with a written list and a count that matches it
Before any door opens, write the count you expect: how many birds are in each section, and which individuals — by ring number, colour, or name — make up that number. Then count the birds in front of you and reconcile the two before you begin. Discrepancies found at this stage are puzzles; discrepancies found afterwards are emergencies. Include the hiding places in your count: nest boxes, feeders with covers, dense planting, and the bird quietly sitting on eggs who will not flush when the others move. If the count is short, find the bird now, while every door is still shut.
Move birds in closed groups to a secure holding space
Never clean around free birds in an open section. Catch or usher the birds, section by section, into a holding cage or a sealed part of the aviary, and count them again as the holding door closes. Work with one door open at a time and close it behind you before opening the next; most escapes during cleaning happen in the few seconds when two doors stand open together and a startled bird takes the straight line out. If you keep pigeons or doves in a loft, use the same discipline with trap and section doors, and keep a net within reach in the holding area rather than outside it.
Count at fixed stages, not when you remember
Build the count into the job at four points: before opening, after birds are shut in holding, before the cleaned section is reopened, and a final count once every bird is back and all doors are secured. Say each count out loud or write it down as you go — a count that lives only in your head evaporates the moment something interrupts you. If anyone helps with the clean, one person owns the counts and the other owns the doors; shared responsibility for both is how a bird ends up counted by nobody. A short count at any stage stops the job until it is resolved, with doors closed while you search.
Design the space so the system is hard to beat
Over time, make the routine easier to get right: a double-door entry or safety porch on the aviary means a bird past the first door is still contained; clear sightlines and fewer bolt-holes make counting faster; and perches or roosting shelves arranged openly mean fewer birds hidden at dusk cleans. Keep the written list on the aviary door itself, updated whenever a bird arrives, leaves, hatches, or dies, so the expected number never lives in memory. Ring or mark youngsters promptly once they are old enough, so individuals in a lookalike flock can be told apart during a recount.
Treat every short count as a lost bird until proven otherwise
If the final count is one down, assume escape, not miscount: recheck nest boxes and holding corners once, then search the immediate surroundings straight away while the bird is likely still close, listening for flock calls, and alert anyone nearby to watch gardens and roofs. Note when the bird was last positively counted — your staged counts narrow the escape window and tell you which door and which hour to think about. Recording each stage of the clean in KinsLe Care Teams, with counts marked complete as you go, leaves a clear trail of exactly when every bird was last accounted for.