[mou] Fwd: [BIRDCHAT] Winter Finch Forecast 2006 - 2007

[Jim Williams]

forward by Jim Williams
Wayzata

Begin forwarded message:

From: Jean Iron <jeaniron@SYMPATICO.CA>
Date: September 8, 2006 8:24:35 AM CDT
To: BIRDCHAT@LISTSERV.ARIZONA.EDU
Subject: [BIRDCHAT] Winter Finch Forecast 2006 - 2007
Reply-To: Jean Iron <jeaniron@SYMPATICO.CA>

GENERAL FINCH FORECAST 2006 - 2007

This is one of those rare years when most conifers (softwoods) and  
broad-leaved deciduous trees (hardwoods) have synchronized bumper seed  
crops across much of Eastern Canada and the bordering United States. It  
will be an excellent winter to see winter finches in northern Ontario  
and central Ontario (e.g., Algonquin Park). Very few boreal finches  
will move south of Ontario this fall and winter. Most finches likely  
will be scarce even in southern Ontario south of the Canadian Shield  
this winter, despite bumper seed crops on native and ornamental  
species. There also are bumper cone crops in Quebec, the Maritime  
Provinces, New York and northern New England States, so finches will be  
there too, but in what numbers is the question, because excellent crops  
are so widespread this year. There are good cone crops west of Lake  
Superior in northwestern Ontario, but cone quality diminishs towards  
Manitoba because of severe drought conditions this year. Cone crops are  
generally poor at the continental extremes in Newfoundland and Alaska.  
Both White-winged and Red Crossbills have been arriving in Ontario  
since late June in areas with bumper cone crops. In addition to  
individual finch forecasts, I also comment on other irruptive species,  
such as the Red-breasted Nuthatch, whose movements are linked to winter  
finches. I added a new section this year called Finch Notes. It  
discusses bumper seed crops, how crossbills find cone crops, when  
crossbills move to bumper crops, when crossbills nest, road-killed  
finches, and where to see finches this winter in Ontario.

INDIVIDUAL FINCH FORECASTS

Pine Grosbeak: Most Pine Grosbeaks will stay in northern Ontario  
because the berry crop on mountain-ash (rowan berries) is excellent to  
bumper this year. As well, the large seed and berry crops on other  
trees and shrubs provide ample buffer food supplies to keep the  
grosbeaks in the north. A few Pine Grosbeaks may drift as far south as  
Algonquin Park where they are seen most winters.

Purple Finch: The excellent tree seed crops on most coniferous and  
deciduous trees suggest that most (not all) Purple Finches will spend  
this winter in northern and central Ontario. Some may drift south in  
late winter and show up at feeders, which is typical of this species in  
big seed years as seed supplies diminish in late winter.

Red Crossbill: Taxonomy and nomenclature are hopelessly confused. The  
Red Crossbill complex comprises at least eight types or forms (possibly  
full species) with different vocalizations and bill sizes related to  
cone preferences. Two or three forms are regular in Ontario. One  
prefers hemlock cones and the others are adapted mostly to pines,  
mainly white pine in Ontario. Red Crossbills have been seen and heard  
singing in hemlocks in August suggesting that the small-billed hemlock  
subspecies 'sitkensis' has moved into central Ontario where hemlock  
cone crops are excellent as in Algonquin Park and the Haliburton  
Highlands. The hemlock form has the smallest bill of all Red  
Crossbills, even smaller than the White-winged Crossbill's stubby bill.  
Road-killed 'sitkensis' can be identified by measuring their bills  
(culmen 13.5-15 mm). White pine cone crops, unlike other conifers, are  
poor in most of central Ontario such as Algonquin Park. However, some  
areas of northeastern Ontario have good white pine crops such as Marten  
River and Timmins. Watch for pine types of Red Crossbills wherever  
white and red pines have good cone crops. Since spruce cones are so  
abundant this year, I expect that Red Crossbills will be found feeding  
in spruce to some extent this winter.

White-winged Crossbill: Like a pendulum, White-winged Crossbills move  
back and forth across the northern coniferous forests from Newfoundland  
to Alaska searching for cone crops. White-winged Crossbills will be  
widespread and perhaps common in many areas of northern and central  
Ontario because of the bumper seed crops on spruces, tamarack, balsam  
fir and hemlock. I expect that the highest concentrations of  
White-wings will be in northeastern Ontario between Lake Superior and  
Quebec where the super bumper crop of white spruce cones is "a  
1-in-20-year cyclical phenomenon" making this is a rather rare event in  
seed production for white spruce (Scott McPherson, pers. comm.).  
White-winged Crossbills began increasing in northern Ontario in late  
June and increased during July associated with big cone crops. They are  
singing and feasting on an abundance of cone seeds and probably  
nesting. They likely will begin nesting again in early 2007.  
White-winged Crossbills in Algonquin Park have been widespread in small  
numbers since July and are singing. Nesting is suggested by two  
sightings of recently fledged young in August. White-winged Crossbills  
possibly came from western Canada and Alaska wandering eastward  
searching for cone crops. One reason why there are no subspecies on  
this continent versus the eight or more types of Red Crossbills is that  
White-winged Crossbill populations oscillate east and west across North  
America, and thus are constantly mixing. This allows outcrossing and  
gene flow among populations, suppressing the formation of geographical  
variation.

Common Redpoll: This is not a flight year for redpolls in southern  
Ontario. Most Common and Hoary Redpolls will be in northern Ontario  
this winter because seed crops on white birch and alder are excellent  
to bumper there. As well, yellow birch has an excellent crop from  
southeastern Lake Superior into Quebec. This large crop will stall any  
redpolls wandering south of the boreal zone. A few redpolls may get as  
far south as Algonquin Park, but likely no farther.

Pine Siskin: Most Pine Siskins will winter in northern and probably  
central Ontario this winter because cones crops are bumper on spruces,  
balsam fir, tamarack (larch), cedar and hemlock. Flocks of siskins can  
be identified at a distance by their distinctive flight formation. They  
swirl in tight flocks whereas redpolls fly in loose undulating flocks.  
Siskins should breed early next spring in northern Ontario. Only one  
subspecies occurs across Canada, indicating that highly nomadic siskin  
populations mix from coast to coast, inhibiting the formation of  
geographical variation.

Evening Grosbeak: Evening Grosbeaks will stay in the boreal forest this  
winter because tree seed crops are excellent on conifers and hardwoods  
such as black ash. Expect a few in Algonquin Park, particularly around  
the feeders at the Visitor Centre. The eastern population of Evening  
Grosbeaks started declining in 1980 as large outbreaks of spruce  
budworm subsided. The population is probably stable now, but much  
reduced from the 1970s when Evening Grosbeaks were common at bird  
feeders.

OTHER IRRUPTIVE SPECIES

Blue Jay: A small to moderate flight is expected. The good to excellent  
crop of beechnuts on American beech in most areas of central and  
southern Ontario should keep most Blue Jays from migrating south this  
September and October along the shorelines of Lakes Ontario and Erie.  
Blue Jays are now actively storing beechnuts. Also, there are excellent  
crops of hazelnuts which will add to the nonmigratory tendency of Blue  
Jays this fall. The red oak acorn crop is poor in most areas of central  
Ontario, but the lack of acorns should be compensated for by the large  
mast crops on other deciduous trees and shrubs.

Red-breasted Nuthatch: Most Red-breasted Nuthatches will not migrate  
south this fall. The bumper cone crops across Ontario will hold most  
Red-breasted Nuthatches close to their northern breeding grounds this  
winter. When Red-breasted Nuthatches winter in the boreal forest they  
eat conifer seeds so are closely linked to finches.

Bohemian Waxwing: The excellent to bumper crop of mountain-ash (rowan  
berries) will keep most Bohemians Waxwings close to the boreal forest  
this winter.

Boreal Forest Owls: The widespread abundance of seeds, berries, nuts  
and fruits (mast) is providing a huge food supply for small mammals  
such as voles so their numbers should be increasing. Most boreal forest  
owls (Northern Hawk Owl, Great Gray Owl, Boreal Owl) likely will stay  
close to breeding territories this winter. Increasing numbers of small  
mammals will increase owl breeding success next spring and summer.

FINCH NOTES

Why Bumper Tree Seed Crops? One theory of bumper crops is to ensure  
adequate seed supplies will germinate above the losses to consumers  
such as fungi, insects, mammals and birds. Many trees have low seed  
production in most followed by periodic bumper crops producing huge  
surpluses beyond the capacity of seed consumers. Tree species normally  
synchronize seed crops with members of their own species across  
hundreds of kilometres/miles and they sometimes synchronize with other  
species as has happened this year in the Northeast. This year's bumper  
crops probably resulted from last year's hot and dry stress conditions  
throughout most of the Northeast. Most plants under stress one year  
will produce more seed the following year as a form of survival. The  
size of the seed crop the following year is largely determined by the  
weather at the time of flowering and pollination. If the weather is too  
cold or too hot the flower buds will not develop properly. If there is  
too much rain during pollination and no wind then poor pollination  
takes place. This year in the Northeast the weather was perfect for  
most conifer and hardwood species. However, white pine and red oak are  
two significant species with poor seed crops in 2006 in central  
Ontario. Why these two species? First, white pine cones take two  
summers to ripen as opposed to spruce, fir, tamarack, cedar and hemlock  
which ripen in one summer. Last year white pine grew a drought stressed  
crop of immature conelets with considerable losses, resulting in a  
generally poor crop maturing this year. Second, red oak had abundant  
flowers in May but produced few acorns this year because the weather  
turned cool and wet just when its flowers were ready to pollinate.

How Do Crossbills Find Bumper Cone Crops? Crossbills (and other  
finches, particularly siskins) can locate big cone crops half a  
continent or more away. Crossbills have well-developed sensory and  
nervous systems and the evidence is clear that they respond to external  
stimuli such as growing seed crops. The ability of crossbills to find  
bumper cone crops suggests something more than random searching, but we  
do not know how they do it. Ian Newton in his classic 1972 book on  
"Finches" suggested that crossbills could assess the potential of  
upcoming cone crops when moving between areas. There is much to learn  
about nomadic winter finches.

When Do Crossbills Move To Bumper Seed Crops? Before big crossbill  
nestings, they normally begin arriving in summer in areas with  
developing bumper cone crops. This summer there were reports of  
crossbills moving in Minnesota, northern Michigan, northeastern Ontario  
(both species), central Ontario (both species in Algonquin Park),  
northern New York State (Red Crossbills), Quebec (White-winged  
Crossbills), northern New Hampshire (White-winged Crossbills), Maine  
(White-winged Crossbills) and New Brunswick (White-winged Crossbills).  
In years when either Red or White-winged Crossbills nested in late  
winter and early spring in Algonquin Park, numbers were high in the  
preceding late summer and fall.

When Do Crossbills Nest? The following information is courtesy of Ron  
Tozer from his draft manuscript for The Birds of Algonquin Park. (A)  
White-winged Crossbills nest during two main periods in Algonquin Park.  
(1) The main nestings are in late December to mid-March with fledged  
juveniles seen from late March to late May. (2) July and August  
nestings produce young seen in early August to mid-October. (B) Red  
Crossbills also nest during two main periods. (1) Adults with dependent  
young have been seen in late April to mid-June from nestings in  
January, February and probably March. (2) Adults with dependent young  
seen from mid-August to late October are from nestings in June and  
probably July. Both species nest occasionally outside the core periods  
described above. Note: The presence of independent streaked young in  
either species does not necessarily indicate local breeding because the  
juvenile plumage can be retained for a considerable time.

Road-killed Finches: This could be a winter when thousands of winter  
finches are killed by cars in places such as Algonquin Park and the  
Haliburton Highlands. Finches are attracted to the salt and sand put on  
highways. They have little fear of cars. I remember one collision that  
killed 63 siskins in Algonquin Park. Common Ravens have an easy time  
patrolling for road kills. When you see finches on the road, slow down,  
flash lights and tap your horn several times. Finches often do not  
respond in time. Be careful not to confuse other drivers.

Where To See Winter Finches: This will be a good year for a winter trip  
to Algonquin Park. The park is a three hours drive north of Toronto.  
White-winged Crossbills and Pine Siskins should be common, although  
siskins have been absent to date. Red Crossbills, Purple Finches and  
Evening Grosbeaks are possible in smaller numbers. A few Pine Grosbeaks  
are likely, but most will be farther north. Redpolls should stay  
farther north this winter in the boreal forest. Drive Highway 60 in  
early morning watching for flocks of finches attracted to the salt and  
sand put on the highway to reduce accidents. There are feeders at the  
Visitor Centre, which is open only on weekends in winter. Arrangements  
can be made to view the feeders on weekdays. For the latest information  
on finches, call the Visitor Centre at 613-637-2828 or e-mail Ron Tozer  
(retired park naturalist) at <rtozer at vianet dot ca>.

ACKNOWLEDGEMENTS

I thank the many birders and staff of the Ontario Ministry of Natural  
Resources (OMNR) whose composite knowledge and reports allowed me to  
make reasonable predictions about finches in Ontario this fall and  
winter. They are Dennis Barry (Durham Region), Shirley Davidson (OMNR  
Minden), Nancy DeWitt (Alaska), Bruce Di Labio (Eastern Ontario),  
Shelagh Duckett (OMNR, Thunder Bay), Chris Fagyal (Minnesota), Tyler  
Hoar (Laurentians, Quebec), Michel Gosselin (Gatineau Hills, Quebec),  
Charity Hendry (Angus Tree Seed Nursery), Leo Heyens (OMNR Kenora),  
Brandon Holden (Algonquin Park), Peter Hynard (OMNR Haliburton), Jean  
Iron (Toronto and Temagami), Bob Knudsen (Ontario Parks, Algoma), Scott  
McPherson (OMNR Northeast Region), Larry Neily (Ottawa),  John Miles  
(Selkirk Provincial Park, Lake Erie), Brian Naylor (OMNR North Bay)  
Janet Pineau (Arrowhead Provincial Park), Fred Pinto (OMNR Sudbury),  
Rick Salmon (OMNR Lake Nipigon), Ron Tozer (Algonquin Park, Marten  
River, Moosonee), Declan Troy (Alaska), Mike Turner (OMNR Brancroft  
District), Stan Vasiliauskas (OMNR Northeast Region), Mike Walsh (OMNR  
Muskoka and Parry Sound) and Matt Young (upstate New York). Matt  
Young's posts this summer on New York State listservs have been  
helpful. I am grateful to Ron Tozer for reviewing this post and for  
information from his draft manuscript for The Birds of Algonquin Park.

RECENT FINCH FORECASTS ARCHIVED

Larry Neily has archived recent finch forecasts at  
<http://ca.geocities.com/larry.neily@rogers.com/pittaway05.htm>http:// 
ca.geocities.com/larry.neily@rogers.com/pittaway05.htm

REFERENCES

1. Bolgiano, N.C. 2004. Cause and Effect: Changes in Boreal Bird  
Irruptions in Eastern North America Relative to the 1970s Spruce  
Budworm Infestations. In 104th Christmas Bird Count 2003-2004 issue.  
American Birds 58:26-33.
2. Newton, I. 1972. Finches. 288 pages. Collins.
3. Pittaway, R. 1998. Winter Finches. OFO News 16(1):5-7.

Ron Pittaway
8 September 2006
Ontario Field Ornithologists
Minden and Toronto ON

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