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Bird Droppings
Dispatches from the nation’s birdwatching capital… by Seymore Thanu
When Blackpoll Warblers begin
turning up in Cape May, you
know fall warbler migration
is nearing its finale. Breeding
across most of Boreal Canada
and Alaska as well as mountain tops in New
York and New England, these bantamweight
forest birds are the long-distance champions
among southbound songbirds. Weighing
less than half an ounce, but nearly twice the
weight of a Northern Parula (warbler), they
jump off from northern New England after
doubling their body weight, then fly nonstop
over the Atlantic to winter grounds in South
America. The 1,800-mile nonstop flight takes
three days, and the birds lose half their weight.
To accomplish this feat, birds jump off with a
northwest tail wind, then rely upon the trade
winds off ofNorth Africa to see them home.
This long and risk-filled route works.
There are fine winter habitats in the Greater
and Lesser Antilles, but these are used by
warblers that lack Blackpoll’s powers of flight.
I’ve noticed in recent years, more Blackpolls
turn up in Cape May. Their growing fall numbers
seem linked to the proliferation of porcelain
berries. This invasive Asian plant is
alleged to have low nutrition value for birds,
but the partiality of Blackpolls and other
fruit-eating birds says different — as does the
proliferation of the berries whose seeds are
widely spread by defecating birds.
Most Blackpolls in fall are yellowish and
vaguely streaky. Find them in the cedars north
of the hawk watch platform at Cape May Point
State Park, the trees in front of the Northwood
Center in Cape May Point and where you find
multi-colored porcelain berries. The other
late-season warbler to watch for is the Yellowrumped
Warbler. This one that winters mostly
in the US, even as far north as Cape May.
Distinguished by their bright yellow rumps,
Yellow-rumped warbler feeds on poison ivy
berries and bayberries, but augmenting their
diets with insects and insect larvae. Wait until
December and you won’t have trouble identifying
it. It’s about the only warbler in town.
Unless you are lucky enough to find a rare
wintering Orange-crowned Warbler or catch
a glimpse of Common Yellowthroat skulking
through the reeds.
If warblers are what you seek, look fast
or wait until Spring. The southbound warbler
express is pulling out of the station. Local
author Scott Whittle’s The Warbler Guide is
a treat, and my good friend Kevin Karlsons
multi-panel warbler cheat sheet is both precise
and concise. Buy both.
September 30, 2021 EXIT ZERO Page 39