Out West, when you climb up past
the treeline, you’re treated to a
view of rugged peaks and expansive
skies, with just a few wizened pines
or firs clinging to the rocky earth. Stop
and listen, and you’ll soon hear the loud
kraak of a Clark’s Nutcracker. Before
long, one of these curious, intelligent
birds is likely to land on a nearby whitebark
pine, completing a scene that’s
thousands of years old.
Without nutcrackers, whitebark pines
might never have made it to these mountains.
Now, in a reversal, recent declines
in whitebark pines might make the birds
scarce, too. That’s the problem I’m studying
in Wyoming as part of my Ph.D. work
at the Cornell Lab of Ornithology.
Clark’s Nutcrackers and whitebark
pines have a fascinating relationship: the
trees provide rich, fatty seeds (with more
calories per pound than chocolate), and
the birds plant them—a single bird may
bury 98,000 seeds in a year. The food
caches help the birds get through the winter,
and the leftovers grow into new trees.
Squirrels hoard pine seeds, too, but
they store them in big heaps called middens,
where few ever germinate. So virtually
all whitebark pines grow from
seeds nutcrackers planted—in fact, nutcrackers
likely carried the ancestors of
whitebark pines with them when they
came to North America across the Bering
land bridge, more than 1.8 million
But now whitebark pines are dying
off, a result of attacks by mountain pine
beetles and white pine blister rust. More
than a decade ago, the trees started to
disappear in Montana and Washington.
This summer, the U.S. Fish and Wildlife
Service classified whitebark pine as a
candidate for listing under the Endangered
Though Clark’s Nutcrackers eat many
kinds of seeds across their range, whitebark
pine is an important food. Sightings
in Montana and Washington seem
to have declined already. The fear is
that this could become a vicious cycle:
if fewer whitebark pines lead to fewer
nutcrackers, and those birds cache fewer
pine seeds, we could wind up with even
fewer whitebark pines.
Such a cycle could have a huge impact
on the Western landscape. In years when
whitebark pinecones are scarce, grizzlies
move down into valleys in search of food.
This inevitably causes more human-grizzly
conflicts. Fewer pines offer less shade
for the snowpack, causing spring floods
and lower river levels in summer. Those
changes in runoff affect cutthroat trout
and human drinking water, too.
For my dissertation research, I’m
studying Clark’s Nutcrackers in the
Greater Yellowstone Ecosystem, where
whitebark pines have begun to decline
but the birds are still common. Federal
agencies are already working hard to restore
whitebark pine ecosystems, but to
protect nutcrackers we’ll need to learn
more about their lives, too.
So I spend most of my year at 9,000
feet, tromping first through snow and
then through swarms of mosquitos to
track nutcrackers with radio transmitters.
I’m learning exactly where these
birds forage and breed, where they harvest
and cache seeds, and what else they
eat other than whitebark pine. By figuring
out what these birds need to survive,
I’ll be able to make recommendations on
ways to conserve them.
It’s hard to imagine hiking through
the northern Rockies without these birds
or their alpine partners, the emblematic
whitebark pines. But I am optimistic that
with good, informed management, these
wild landscapes will always echo with
the calls of nutcrackers.