Wednesday, September 19, 2012

Winter finch predictions!

The always eagerly anticipated Ron Pittaway report on the state of the boreal forest's various fruit crops, and his attendant predictions as to what might happen in regards to winter finch movements, arrived today. Ron is with the Ontario Field Naturalists, and he employs a small army of observers to provide him data on the cone and other fruit crops around eastern Canada. Many birders and biologists look forward to the annual Pittawayian Prognostications, as Ron is often pretty well spot on in foretelling the movements of boreal birds.

The forecast is promising. Ron believes that we'll see good southward flights of redpolls, Purple Finch, and as is already happening, Red Crossbill. Birders in Ohio will likely find themselves lurking around cemeteries with lots of mature conifers this winter. Who knows, we may even get a Bohemian Waxwing or Pine Grosbeak this winter.

MINOR GRIPE: The Pittaway forecast - and many other reporters - constantly refer to a lack of cone or other fruit crops as a "failure", meaning the trees did not produce abundant cones. The lack of fruit production in trees is certainly not a "failure"; most woody plants and conifers in particular have boom and bust fruit production cycles. Lean years and boom years are an integral part of their life cycle as the plants alternate between putting energy into seed production, and years that they must recharge their batteries, so to speak. A lack of a crop is really just a lean production year, not a failure.

Here's Ron's report:

WINTER FINCH FORECAST 2012-2013

The theme this winter is that each finch species will use a different
strategy to deal with the widespread tree seed crop failure in the
Northeast. It will be a quiet winter in the eastern North Woods. See
individual species forecasts for details. Both coniferous and hardwood
tree seed crops are generally poor from northeastern Ontario extending
eastward across Quebec to Newfoundland south through the Maritime
Provinces, New York and New England States. Within the Northeast there
are pockets of good crops. Cone crops are much better in the Hudson Bay
Lowlands and northwestern Ontario west to Alberta, Northwest Territories
and Yukon. Three irruptive nonfinch passerines whose movements
are linked to finches are also discussed.

INDIVIDUAL FINCH FORECASTS

PINE GROSBEAK
A good flight is expected into southern Ontario because
the mountain-ash berry crop is variable in the boreal forest.
Many berries are hard with low moisture content because of the drought.
The European mountain-ash and ornamental crabapple crops are poor to
fair in southern Ontario so these crops won't last long.
Grosbeaks will be attracted to the usually abundant buckthorn berries
and to bird feeders offering black oil sunflower seeds. The Ontario
breeding population of this grosbeak is stable.

PURPLE FINCH
Most Purple Finches will migrate south of Ontario this
fall because both coniferous and deciduous hardwood seed crops are very
low this year in the Northeast. Purple Finch numbers dropped
significantly in recent decades as spruce budworm outbreaks subsided and
currently a moderate population decline continues in the province.

RED CROSSBILL
Red Crossbills comprise at least 10 types
in North America. Each type probably represents a separate or newly
evolving species. Most types are normally impossible to identify in the field without
recordings of their flight calls. Matt Young of The Cornell Lab of Ornithology reports that there is currently a large early irruption of Type 3 Red Crossbills (smallest billed type) from the west into eastern North
America. Recordings can be made with a cell phone and sent to Matt to be
identified (may6 AT cornell.edu). Every recording adds an important
piece to the puzzle, especially when accompanied by notes on behaviour
and ecology, including tree species used for foraging and nesting. Matt
emphasizes that the conservation of call types depends on understanding
their complex distributions and ecological requirements.

WHITE-WINGED CROSSBILL
With very poor spruce cone crops in the
Northeast, most White-winged Crossbills will likely stay this winter in
the Hudson Bay Lowlands, northwestern Ontario and western Canada where
spruce cone crops are generally very good. They will be virtually absent
from traditional hotspots such as Algonquin Park where spruce crops are
very low. Wandering birds may show up throughout the Northeast.

COMMON REDPOLL
There should be a good southward flight because the
white birch seed crop is poor to fair across the north. Watch for
redpolls on birches and in weedy fields and at bird feeders offering
nyger (preferred) and black oil sunflower seeds. Check flocks for the
rare Greater Common Redpoll (subspecies rostrata) from
the High Arctic. It is reliably identified by its larger size, darker
and browner colour, longer/thicker bill and longer tail in direct
comparison to Southern Common Redpolls (nominate flammea
subspecies). Note: The notion of a biennial periodicity
that redpolls irrupt south every second winter is not supported by
records in Atlantic Canada (Erskine and McManus 2003). The authors
concluded that "irregular abundance but near-annual occurrence" of
redpolls in the Atlantic Provinces is a better explanation than a two
year cycle. Similarly redpolls were recorded on 32 of 38 Christmas Bird
Counts in Algonquin Park (Lat. 45.5 N), Ontario.

HOARY REDPOLL
Check redpoll flocks for Hoary Redpolls. There are two
subspecies. Most Hoaries seen in southern Canada and northern United
States are Southern Hoary Redpolls (subspecies
exilipes). Hornemann Hoary Redpoll (nominate
subspecies hornemanni) from the High Arctic was previously regarded as a
great rarity in southern Canada and the northern United States. In
recent decades a number have been confirmed by photographs. Hornemann
is most reliably identified by its larger size in direct
comparison to flammea Common Redpoll or exilipes Hoary Redpoll.
Caution: White birds loom larger than life among darker birds and size
illusions are frequent.

PINE SISKIN
Some siskins currently in the Northeast should move south
this fall and winter because cone crops are poor. However, siskins are
an opportunistic nomad wandering east and west continent-wide in search
of cone crops. Most siskins will probably winter in northwestern Ontario
and western Canada where cone crops are generally very good. Major
southward irruptions occur when cone crops fail across most of North
America.

EVENING GROSBEAK
This spectacular grosbeak is ABA Bird of the
Year in 2012. We can expect some at feeders in central Ontario and
probably elsewhere in the Northeast because coniferous and hardwood tree
seed supplies are low. Highest breeding densities are found in areas
with spruce budworm outbreaks. The larvae are eaten by adults and fed to
young. Current populations are much lower than several decades ago when
budworm outbreaks were much larger and more widespread.

THREE IRRUPTIVE PASSERINES
Movements of the following three species are
often linked to the boreal finches.

BLUE JAY
Expect a smaller flight than last year along the north
shorelines of Lakes Ontario and Erie because the red oak acorn crop is
very good in central Ontario. Beechnut and hazelnut crops were poor to
none, but the acorn crop may be large enough to keep many jays in the
north this winter.

RED-BREASTED NUTHATCH
A widespread irruption of this nuthatch beginning
in mid-summer indicated a cone crop failure in the Northeast. Most will
leave the eastern half of the province for the winter, but some will
probably remain in northwestern Ontario where cone crops are much
better.

BOHEMIAN WAXWING
Expect a flight this winter because the mountain-ash berry crop in the boreal forest was affected by drought. Even though some areas have large crops, many berries are hard with low
moisture content. Farther south Bohemians will be attracted to the usually abundant buckthorn berries because European mountain-ash and ornamental crabapple crops are generally low and of poor quality.

WHERE TO SEE FINCHES
Algonquin Park is a winter adventure about a three
hour drive north of Toronto, but this will be a very lean finch winter
in the park. Conifer crops are poor to none. Feeders at the Visitor
Centre (km 43) should have Pine Grosbeaks, Evening Grosbeaks, and redpolls. The
Visitor Centre and restaurant are open weekends in winter. Arrangements
can be made to view feeders on weekdays by calling 613-637-2828. The nearby Spruce Bog Trail at km 42.5 and Opeongo Road are good spots for Gray Jays, Boreal Chickadees, Spruce Grouse and Black-backed Woodpeckers. Be sure to get a copy of the new Birds of
Algonquin Park (2012) by Ron Tozer. It is one of the best
regional bird books ever published with lots of information about winter
finches and boreal specialties.
http://store.algonquinpark.on.ca/cgi/algonquinpark

WINTER FINCH BASICS: A primer about finch facts, seed crops and
irruptions.
http://www.jeaniron.ca/2011/WinterFinches.pdf

Excellent paper on berry crops in Ontario.
http://people.trentu.ca/jebowman/Howeetal2012.pdf

ACKNOWLEDGEMENTS: I thank staff of the Ontario Ministry of Natural
Resources designated by an asterisk* and others whose reports allow me
to make annual forecasts:
Dennis Barry (Durham Region), Eleanor Beagan (Prince Edward
Island), Pascal Cote (Tadoussac Bird Observatory, Quebec), Bruce Di
Labio (Eastern Ontario and Churchill, Manitoba), Carolle Eady (Dryden),
Cameron Eckert (Yukon), Marcel Gahbauer (Alberta & Northwest
Territories), Michel Gosselin (Canadian Museum of Nature), David
Govatski (New Hampshire), Charity Hendry* (Ontario Tree Seed Facility),
Leo Heyens* (Kenora), Tyler Hoar (Northern Ontario & Quebec
Laurentians), Jean Iron (Hudson Bay, James Bay & Northeastern Ontario),
Bruce Mactavish (Newfoundland), Brian Naylor* (Nipissing), Justin Peter*
(Algonquin Park), Genevieve Perreault (Regroupement QuebecOiseaux), Fred
Pinto* (North Bay), Harvey & Brenda Schmidt (Creighton, Saskatchewan),
Ron Tozer (Algonquin Park), Declan Troy (Alaska), Mike Turner
(Haliburton Highlands), John Woodcock (Thunder Cape Bird Observatory)
and Kirk Zufelt (Sault Ste Marie, Ontario). I especially thank Matt
Young of The Cornell Lab of Ornithology for advice and detailed
information about seed crops in New York and adjacent states and for
information about Red Crossbills. Jean Iron proofed the forecast and
made helpful comments.

LITERATURE CITED: Erskine, A.J. and R. McManus, Jr. 2003. Supposed
periodicity of redpoll, Carduelis sp., winter visitations in Atlantic
Canada. Canadian Field-Naturalist 117(4):611-620.

Ron Pittaway
Ontario Field Ornithologists
Minden, Ontario
19 September 2012

1 comment:

Robb said...

So, we would appear to have a pretty decent shot at seeing several of these species move into Ohio this season?