1 Articles Northern Owls in Sudbury and Manitoulin Districts: High Numbers, Out of Season Occurrences and Breeding Charles J. Whitelaw Introduction and Manitoulin districts. As many This article reviews the status of the as five or six birds could frequently Great Gray Owl (Strix nebulosa), be seen on a given day in the the Snowy Owl (Nyctea scandiaca) Sudbury Region, many within the and the Northern Hawk Owl city itself. The peak was reached by (Surnia ulula) in the Sudbury and early February, when as many as 25 Manitoulin districts of Ontario. Past were found on a single day on records of the Sudbury Ornitho­ Manitoulin Island. Toward the lat­ logical Society and the Manitoulin ter part of February, a storm Nature Club have been searched brought freezing rain which soon (Nicholson 1970-1994, Lemon 1994­ covered the country with ice. 1997). Available records go back as Before long, there was evidence of far as 1967, a period of 30 years. widespread starvation among the population of visiting Great Gray Great Gray Owl Owls. Dead birds were picked up in During the 1970s and throughout a number of locations, and many most of the 1980s, the Great Gray were shot by the ill-informed Owl has been an irregular and (Rodney Campbell, pers. comm.). uncommon winter visitor, with most During the winter of 1993-94, appearances during the period of an invasion occurred which fol­ December to March. In some years, lowed much the same pattern as they have not shown up at all. two years earlier. Numbers matched those of the earlier inva­ Recent Visitations sion, particularly on Manitoulin During the winter of 1991-92, Great Island. Grays showed up in rather large numbers. The first arrivals were Out of Season Occurrences seen by early December 1991. By The Great Gray Owl normally January 1992, sightings became breeds far to the north of Sudbury rather frequent in both Sudbury and Manitoulin districts (Peck and VOLUME 16 NUMBER 1 2 James 1983). However, there has Northern Hawk Owl has been an been recent breeding in Algonquin irregular and uncommon winter vis­ Provincial Park (Forbes et al. 1992), itor to Manitoulin and the southern and as well, there is a very old Sudbury districts during the 1970s (1911) breeding record from and 1980s. Individuals have gener­ Chisolm Township, Nipissing ally appeared by mid November District (James 1991). and stayed until late December in More recently, in late April and most cases, after which most have early May of 1997, a single adult bird moved on. The odd one has been was seen several times in known to stay for the entire winter, Tehkummah Township, Manitoulin occupying a hunting territory which Island (Don Ferguson, pers. comm.). was established shortly after arrival The mate of this bird, if one was in in November. In the 1990s, the the area, was not located. During numbers of individuals seen during February 1997, as many as six Great November has generally increased. Gray Owls were found in a single day At the same time, the regularity of on Barrie Island, Manitoulin. Late overwintering birds during these into the spring (June), individual years has also increased. birds were seen on occasion on the north side of Barrie Island. During High Numbers July, two birds were seen together in The winter of 1996-97 saw Northern the same general area. A juvenile Hawk Owls overwinter on Barrie Great Gray Owl (still with down Island, Manitoulin in unprecedent­ feathers) was photographed in mid ed numbers. Barrie Island is a town­ August at 45° 56' 12" north latitude ship joined to mainland Manitoulin on Barrie Island, by Camille by a short causeway. It is strictly a Campbell. On 15 September 1997, rural farming community. Road three birds were seen together at this access during the winter months is location, two of which were believed limited to an area of about ten to be young of the year. These partic­ square kilometres, yet during ular birds showed some down feath­ January and February of 1997, as ers, were generally quite dark with no many as 11 Northern Hawk Owls white crescent at the chin, and had were tallied in this area on a single shorter tails than an adult bird nor­ day. The high numbers appeared to mally has. On 17 September, two be due to an extremely high vole were seen, one of which was a juve­ (Microtus pennsylvanicus) popula­ nile. On 21 September, one adult was tion. This particular invasion did seen. Local nesting was strongly sus­ lead to a confirmed nesting. pected. Northern Hawk Owl Out of Season Occurrences As with the Great Gray Owl, the At least two pairs of Northern ONTARIO BIRDS APRIL 1998 3 Hawk Owls nested and raised fami­ by the Militia of the Canadian lies during 1997 on Barrie Island, Army for training exercises. Access Manitoulin (Campbell et al. 1998). to the property by birdwatchers is In both cases, family groups were not always available, although entry seen together on their home territo­ is generally possible on weekends. ry after the young were fledged in the month of June. Snowy Owl In Sudbury District, there are Of the three species dealt with in records of two cases where an indi­ this report, the Snowy Owl has pos­ vidual bird, and possibly a mated sibly been the most consistent as a pair, spent the summer on a territo­ winter visitor. Again, the Snowy ry. In neither case was there any evi­ Owl has generally shown up in dence of successful nesting. The first November, with most birds moving of these occurred near the commu­ on farther south, but occasionally nity of Whitefish, just west of the the odd one has overwintered. The city of Sudbury, where a single bird one exception to this pattern was in was seen regularly throughout the the winter of 1971-72, when as summer of 1996, from 14 June until many as 33 Snowies were believed 1 October (Igor Konikow, pers. to have overwintered in and around comm.). The second summer occur­ the city of Sudbury (Young 1973). rence of the Northern Hawk Owl in the southern part of the Sudbury Out of Season Occurrences District was on the former Burwash During the winter of 1996-97, when Industrial Farm property, south of large numbers of Great Gray Owls the city. One bird occupied a terri­ and Northern Hawk Owls overwin­ tory beginning in December 1996. tered on Barrie Island, Manitoulin, This bird, and occasionally two, there were two Snowy Owls also were seen here throughout the win­ present. At least one of these, ter and into the following spring believed to be an adult male, stayed (Heather Baines, pers. comm.). On throughout the following spring 1 June 1997, the Sudbury Ornitho­ and summer on Barrie Island. logical Society had a field outing to Unfortunately, it was found dead on the Burwash property. One of the 1 September 1997. A second Snowy Northern Hawk Owls cooperated Owl also spent at least part of the and was seen by most members pre­ summer of 1997 in nearby Gordon sent that day. One or sometimes Township (Doreen Bailey, pers. two birds were seen on occasion comm.). This particular bird was during the summer. The last sight­ believed to be an adult female, or ing was on 24 September 1997. possibly an immature bird, as it was There was no evidence of nesting. very heavily marked. This recent The Burwash site is currently used occurrence of Snowy Owls during VOLUME 16 NUMBER 1 4 the summer in Ontario appears to Literature Cited be unusual (James 1991); however, Bent, A.C. 1938. Life Histories of North the species has been observed dur­ American Birds of Prey. Part 2. United ing summer in the settled parts of States National Museum Bulletin 170. .Washington, D.C. eastern North America in the past Campbell, R.S., F.C. Cosby and e.J. (Bent 1938). Whitelaw. 1998. Nesting of the Northern Hawk Owl on Manitoulin Island in 1997. Conclusion Ontario Birds 16: 5-10. Forbes, G., M. Runtz and R. Tozer. 1992. In summary, there is some evidence New breeding record for Great Gray Owl: that the numbers of invading and most southerly in Canada. Ontario Birds overwintering northern owls, and 10: 117-118. their occurrence during the nesting James, R.D. 1991. Annotated Checklist of the Birds of Ontario. Life Sciences season, have increased in recent Miscellaneous Publications. Royal years in Sudbury and Manitoulin Ontario Museum, Toronto. districts. Lemon, J. 1994-1997. Monthly bird reports - Sudbury and Manitoulin districts. Mimeographed. Acknowledgements Nicholson, ,J.C. 1970-1994. Monthly bird The author wishes to acknowledge reports - Sudbury and Manitoulin dis­ with thanks the records of northern tricts. Mimeographed. owls from Doreen Bailey, Heather Peck, G.K. and R.D. James. 1983. Breeding Birds of Ontario: Nidiology and Baines, Chris Bell, Camille Distribution. Volume1: Non-passerines. Campbell, Rodney Campbell, Roy Life Sciences Miscellaneous Publi­ Campbell, Igor Konikow, and cations. Royal Ontario Museum, Toronto. George Peck; and a review of the Young, C.M. 1973. The Snowy Owl migration of 1971-72 in the Sudbury region of preliminary draft of this report with· Ontario. American Birds 27: 11-12. some valuable suggestions by Chris Blomme and George Peck. Charles J. Whitelaw, 4195 Frost Avenue, Hanmer, Ontario P3P 1E3 ONTARIO BIRDS APRIL 1998.