Owls can be sensitive to close approach by humans, and are more easily disturbed than many other bird species. For this reason, it is not always advisable to report the exact location of owl sightings on the Vancouver Rare Bird Alert. The reporting of owl sightings, either on the RBA or in public e-mail messages, should be governed by the following general guidelines:
The sensitivity to disturbance varies greatly by owl species and by time of year. Specific guidelines for each owl species in the Vancouver area are listed below.
BARN OWL-- Fairly common in the Vancouver area, nesting mainly in barns, nest boxes, and other man-made structures (e.g. the tower of the Burrard Bridge at one time). This species is well-adjusted to living with humans; although an owl may flush when one enters a barn during the daytime, it usually has at least one other habitual roosting spot to which it will move if it is accidentally disturbed. OK to report all sightings, although this species is common enough that it does not rate mention on the RBA. One point to keep in mind is that most known locations are on private property, and permission to enter a barn (or other private property) should be obtained in advance.
FLAMMULATED OWL-- Only one record for the Vancouver area, and unlikely to be seen again soon. The species does not breed in the area or overwinter in the area, and is likely to occur only as a very rare passage migrant. OK to report sightings.
WESTERN SCREECH-OWL-- Coastal populations have declined dramatically, apparently mainly as a result of Barred Owl predation, and the coastal subspecies (kennicotti) is now officially listed as Threatened by COSEWIC. Coaxing Screech-Owls into calling by the use of recorded tapes could possibly expose them to Barred Owl predation. It is preferable that no sightings should be reported in public.
GREAT HORNED OWL-- Fairly common in the area, with stable numbers, and not very sensitive to disturbance. OK to report sightings, although too common to be mentioned on the RBA.
SNOWY OWL-- Present only in winter, in good numbers only in infrequent flight years, and highly sought after by birders and photographers. The main problem is too-close approach by over-zealous photographers, which can cause birds to flush, although there is little evidence that this causes harm to the birds. Close approach should be avoided. Individual birds are very conspicuous and may stay in the same spot for months, so suppression of sighting reports would not be effective, even if it were considered desirable. OK to report all sightings.
NORTHERN HAWK OWL-- Very rare in the area, and found only in winter. Diurnal, and largely oblivious to humans. OK to report all sightings.
NORTHERN PYGMY-OWL-- Uncommon in the area, diurnal, and found mainly on the North Shore. Has nested in the area. Sightings in the breeding season should probably not be reported to avoid disturbing nest; otherwise OK to report.
BURROWING OWL-- Very rare in the area, likely to occur only in the non-breeding season, and considered Endangered in BC. Because of Endangered status, sightings should not be reported in public
SPOTTED OWL-- Endangered in BC and Canada, and rapidly declining. Sightings should never be reported in public.
BARRED OWL-- Common in the area, perhaps still increasing, and so much of a threat to Spotted Owls that control programs are being considered in the US and in BC. OK to report all sightings, although too common generally to be mentioned on the RBA.
GREAT GRAY OWL-- Very rare in the area, secretive, and likely to occur only in winter. Partly diurnal in activities; very much sought after by birders and photographers. Generally almost oblivious to humans. Despite claims to the contrary, we know of no situations in the Vancouver area where Great Grays have been harmed by birders and photographers, or have abandoned an area because of numerous birders. OK to report all sightings. East of the Cascades, where nesting occurs, sightings during the breeding season should not be reported in public.
LONG-EARED OWL-- Uncommon to rare in the Vancouver area, mostly in winter. Nesting has been reported in the area, but not in recent years. Birds are easily flushed from daytime roosting sites, and repeated disturbance may cause abandonment of such roosting sites. Sightings should not be reported in public.
SHORT-EARED OWL-- Relatively common, partly diurnal in activities, and not very sensitive to disturbance-- except in large communal roosting sites, which are rarely if ever reported these days. OK to report all sightings, EXCEPT FOR locations of communal roosts and of sightings during the breeding season.
BOREAL OWL-- Very rare in the area-- only a couple of sightings, and does not breed. Roosts generally in dense conifers, like the N. Saw-whet owl. May roost in the same location for several days or weeks. OK to report sightings, but close approach should be avoided.
NORTHERN SAW-WHET OWL-- Fairly common, and breeds in the area; strictly nocturnal. In the daytime, roosts usually in dense cover, and may roost in the same spot for weeks or months. Flushing a bird from a daytime roost could possibly expose it to predation or harassment by crows, or result in it adopting a less favourable roost site. OK to report sightings, but close approach should be avoided, except that sightings in the breeding season should NOT be reported.
Drafted by Wayne C. Weber Approved by the Birding Section Committee of Nature Vancouver April 17, 2013