[mou] winter finch forecast

[Jim Williams]

Begin forwarded message:

From: Jean Iron <jeaniron at SYMPATICO.CA>
Date: September 18, 2008 11:56:53 AM CDT
To: BIRDCHAT at LISTSERV.ARIZONA.EDU
Subject: [BIRDCHAT] Winter Finch Forecast 2008-2009
Reply-To: Jean Iron <jeaniron at SYMPATICO.CA>

GENERAL FORECAST
This winter's theme is where will crossbills go and will they irrupt  
south? Both species wandered widely this summer. Cone crops are poor  
in the Atlantic Provinces and fair to moderate in Western Canada. In  
Ontario, spruce crops are fair to good west and east of Lake Superior  
and in central Ontario such as Algonquin Park, but cone abundance  
diminishes rapidly northwards into the boreal forest. White pine  
(Ontario's provincial tree) has heavy cone crops in most areas. The  
hemlock crop is poor in central Ontario. The white birch crop is fair  
to good west and east of Lake Superior to Lake Ontario, but poor in  
the boreal forest. The mountain-ash (rowan berry) crop is excellent  
in Ontario and Western Canada, but poor in the Atlantic Provinces.  
Individual finch forecasts below apply mainly to Ontario, but  
adjacent provinces and states may find the forecast of interest. I  
also comment on three irruptive passerines and two boreal forest  
raptors.

INDIVIDUAL FINCH FORECASTS
Pine Grosbeak: A mountain-ash berry specialist in winter, Pine  
Grosbeaks will stay north of most birders this winter because  
mountain-ash berries are abundant in northern Ontario. A few normally  
get south to Algonquin Park, but they are unlikely farther south.

Purple Finch: This finch stays in the north only when most tree  
species have heavy seed crops. This fall most Purple Finches will  
migrate south out of the province because overall tree seed crops are  
too low. A very few may winter in southern Ontario.

Red Crossbill: This crossbill comprises nine ecotypes in North  
America; each has cone(s) preferences related to bill size and shape.  
The Types are difficult to identify in the field. Types 2 and 3 and  
probably 4 occur in Ontario. The white pine Type 2 is apparently the  
most frequently encountered Red Crossbill in the province (Simard  
2007 in Atlas of Breeding Birds of Ontario). Since white pine has  
abundant crops in most areas, expect Type 2s to be widespread in  
small numbers. Hemlock Type 3 (subspecies sitkensis of AOU Check-list  
1957) prefers the small cones of hemlock and white spruce when bumper  
in Ontario. Type 3s should be absent from the province this winter  
because the hemlock crop is poor and the white spruce crop is  
average. Other Types are possible this winter given the bumper white  
pine cone crop and good crop on red pine. The Red Crossbill complex  
very much needs further study.

White-winged Crossbill: This crossbill wandered widely this past  
summer searching for extensive spruce cone crops. Reports came from  
Alaska, Yukon, Hudson Bay Lowlands, Ontario, Quebec and many northern  
states such as Michigan and New York. Most kept moving but some  
stopped and their singing suggested nesting but spruce cone crops are  
generally not large enough in most areas to support major nestings.  
The White-winged Crossbill specializes on the small soft cones of  
black and white spruces and hemlock when bumper in Ontario. This  
winter they should be widespread in small numbers in traditional  
areas such as Algonquin Park. However, spruce cone crops are  
generally low in most of Canada and as seed supplies are exhausted  
this fall and winter so a moderate southward irruption is probable,  
perhaps extending south into the central United States. Watch for  
them on ornamental spruces and European larch.

Common and Hoary Redpolls: The Common Redpoll is a white birch seed  
specialist in the boreal forest in winter. White birch crops are poor  
in the northern two-thirds of the boreal forest, but seed abundance  
increases southward. In central Ontario, such as Algonquin Park,  
crops on white and yellow birches range from fair to good. It is  
uncertain whether the birch crop is large enough to stop the  
southward movement in central Ontario about latitude 45 degrees. Some  
redpolls, including a few Hoarys, may get south to Lake Ontario if  
birch seed supplies run low.

Pine Siskin: A conifer seed specialist in winter, most siskins should  
leave the province this fall because the spruce cone crop is poor in  
the boreal forest. It is uncertain whether the huge white pine seed  
crop will keep some siskins in central and northern Ontario this winter.

Evening Grosbeak: A conifer and hardwood seed generalist in winter,  
Evening Grosbeaks should make a small southward movement this winter  
because food supplies are probably sufficient in the north. Older  
birders remember the 1970s when the Evening Grosbeak was a common  
feeder bird. Their memory is based on the greatly inflated numbers 30  
years ago in Eastern Canada due to huge outbreaks of spruce budworm.  
The last Algonquin Christmas Bird Count to have high numbers of  
Evening Grosbeaks was in 1984 with 1474 individuals, which was the  
North American CBC record that year. A significant decline in  
grosbeak numbers began in the mid-1980s because the size of annual  
budworm outbreaks decreased. Ontario's breeding population is  
currently probably stable, subject to periodic fluctuations in spruce  
budworm (Hoar 2007 in Atlas of Breeding Birds of Ontario).

THREE IRRUPTIVE PASSERINES
Red-breasted Nuthatch: Movements of this nuthatch are linked to cone  
crop abundance, particularly spruce, white pine and balsam fir in  
Ontario. Good numbers of Red-breasted Nuthatches should winter in  
Ontario this year feeding on the bumper white pine seed crop and good  
spruce/fir crops in many areas such as Algonquin Park.

Bohemian Waxwing: Like the Pine Grosbeak, this waxwing is a mountain- 
ash berry specialist in winter. Mountain-ash crops are excellent  
across northern Ontario (bumper around Lake Superior) so very few  
Bohemians will wander out of the boreal forest this winter. Some may  
get south into traditional wintering areas of central Ontario such as  
Orillia, Peterborough and Ottawa where European mountain-ash berries  
are in good supply.

Blue Jay: Good numbers of jays will winter in central Ontario because  
the red oak acorn crop is good and beechnut crop is fair in central  
Ontario. Many other fruits and berries are abundant. Therefore this  
fall's flight should be average or smaller along the shorelines of  
Lakes Ontario and Erie.

BOREAL RAPTORS
Northern Goshawk: A small flight is possible this fall because high  
snowshoe hare populations have declined in much of northern Ontario.  
However, grouse numbers (Ruffed, Spruce, Sharp-tailed) are generally  
good so they may buffer the decline in hares.

Boreal Owl: Small mammal populations have crashed across northern and  
central Ontario. In Quebec, Pascal Cote of Observatoire d'oiseaux de  
Tadoussac expects a flight of Boreal Owls this fall and winter  
following their 4 year cycle linked to red-backed voles. Southern  
Ontario may get Boreal Owls and other northern forest owls this winter.

ACKNOWLEDGEMENTS: I thank staff of the Ontario Ministry of Natural  
Resources (OMNR) and birders whose reports allow me to make annual  
forecasts: Dennis Barry (Durham Region), Ken Corston (OMNR Moosonee),  
Pascal Cote (Tadoussac, Quebec), Shirley Davidson (OMNR Minden),  
Bruce Di Labio (Ottawa to Moosonee), Carrolle Eady (Dryden), Cameron  
Eckert (Yukon), Bruce Falls (Brodie Club, Toronto), Brian Fox (OMNR),  
Marcel Gahbauer (Alberta), Michel Gosselin (Canadian Museum of  
Nature), Skye Haas (Michigan), Charity Hendry (Ontario Tree Seed  
Plant), Leo Heyens (OMNR Kenora), Tyler Hoar (Laurentians and  
Northeastern Quebec), Peter Hynard (Haliburton County), Jean Iron  
(Northeastern Ontario/James Bay), Christine Kerrigan and Peter Nevin  
(Parry Sound District), Richard Pope (Lake Superior), Bruce Mactavish  
(Newfoundland), Erwin Meissner (West Sudbury District), Scott  
McPherson (OMNR), Brian Naylor (OMNR North Bay), Larry Neily  
(Ottawa), Stephen O'Donnell (Parry Sound District), Fred Pinto  
(OMNR), Betsy Potter (Wilson, New York), Gord Ross (OMNR Moosonee),  
Rick Salmon (OMNR Nipigon), Don Sutherland (OMNR), Eve Ticknor  
(Ottawa), Ron Tozer (Algonquin Park), Declan Troy (Alaska), Mike  
Turner (OMNR Minden), Stan Vasiliauskas (OMNR), Mike Walsh (OMNR  
Muskoka/Parry Sound), Ben Walters (Northeastern Ontario), Alan  
Wormington (Point Pelee), Matt Young whose posts on New York State  
listservs were informative, and Kirk Zufelt (Sault Ste Marie). I  
thank Ron Tozer for ongoing discussions on winter finches and Jean  
Iron for proofing the forecast.

PREVIOUS FINCH FORECASTS archived at Larry Neily's website.
http://www.neilyworld.com/pittaway-old.htm

Ron Pittaway
Minden and Toronto ON
18 September 2008

forward by Jim Williams
Wayzata