Posted by Mark Andrew Conboy
Numerous species of birds in Ontario have expanded their ranges further north in during the past century. For example, the Turkey Vulture (Cathartes aura) has dramatically extended its range throughout Southern Ontario beginning in the early 1900’s, when it was rare in most of the province but is today a common species north into parts of Central Ontario. Mourning Dove (Zenaida macroura), Northern Cardinal (Cardinalis cardinalis), Orchard Oriole (Icterus spurius) and perhaps even Cerulean Warbler (Dendroica cerulea) have all undergone similar range expansions (Cadman et al 2007). In recent decades this pattern has continued with the Red-bellied Woodpecker (Melanerpes carolinus), which is now being sighted with increasing frequency in Eastern Ontario.
Red-bellied Woodpeckers have always been considered fairly rare at QUBS so their apparent sudden increase in the area is of considerable interest. I have been recording occurrences of this species on our properties since 2008. I summarize those observations below:
1 on the Moores Tract
2 at the southeast corner of Hughson Tract (copulation reported by Frank Phelan)
1 at Lindsay Lake Road
1 at the Southeast corner of Hughson Tract
1 on Lindsay Lake Road
2 in Silver Maple Swamp
2011 (to date)
1 north of Warner Lake
1 at QUBS Point (visited bird feeders at Ironwood Cottage)
1 on Old Bedford Road
1 on Lindsay Lake Road
2 at the Dowsley Ponds
Additional sightings from the QUBS area reported on eBird (http://ebird.org/content/ebird/) by other observers are: 1 at “QUBS” in 2008 (Martin Piorkowski); 1 at Bedford Mills in 2010 (Peter Blancher); 1 at the cemetery on Opinicon Road (Patrick Blake) and 1 in Elgin (North Leeds Birders), both in 2011. So far the only breeding evidence we have is a pair observed copulating on the Hughson Tract in 2008 (Phelan, personal communication). Observations of Red-bellied Woodpeckers from other parts of Eastern Ontario include occasional eBird reports from Charleston Lake (to the south of QUBS) are starting in 2005 and the Ottawa area (to the north) starting in 2009.
Why Red-bellied Woodpeckers are now expanding into Eastern Ontario with success at this time is unclear. Possible explanations include changing climate contributing to increased winter survival; additional foraging opportunities resulting from bird feeders; and maturation of second-growth forests providing appropriate breeding habitat. The most recent edition of the Atlas of the Breeding Birds of Ontario 2001-2005 showed that 15 species expanded their range edge northward in Ontario in the 20 years since the first edition of the atlas. The northward expansion of most of these species may be attributable to any or all of the aforementioned hypotheses for the Red-bellied Woodpecker.