Adaptation

Semipalmated Sandpipers look right at home on the tundra, where their feathers keep them warm from the constant wind and cold.

Semipalmated Sandpipers look right at home on the tundra, where their feathers keep them warm from the constant wind and cold.

 

Biologists think a lot about adaptation to the environment.  In the struggle of life, animals and plants that evolve ways to cope with the stresses of their environment survive to reproduce, and send a new generation like them into the future to carry on their genetic lineage.  The success or failure of this long journey through time is what separates the species we see from those that have gone extinct.  As we walk around the tundra, studying creatures exquisitely adapted to this harsh arctic environment, I’ve been thinking a lot about the contrast between how well they are adapted, and how poorly we are, to this climate and landscape.

Some of the two thousand pounds of gear we brought with us to survive on the arctic tundra.  The birds came with nothing at all!

Some of the two thousand pounds of gear we brought with us to survive on the arctic tundra. The birds came with nothing at all!

 

It starts with the trip here.  Semipalmated Sandpipers fly from the northern coast of South America, making strategic refueling stops at critical wetlands along their migration route.  Manomet Center for Conservation Sciences works with governments and partner organizations across the hemisphere to help protect these sites through the Western Hemisphere Shorebird Reserve Network.  The birds bring no baggage on their journey, just their tiny bodies which weigh about as much as two AA batteries, and even with stopovers to feed they make the journey in a few weeks.  In contrast, we start planning months in advance.  Three airline flights and a long bush plane ride bring us to this uninhabited arctic island carrying two thousand pounds of gear and supplies we need to survive here. In a week we would stagger only a few miles by foot shuttling all that baggage.

Walking on the tundra is always challenging, but at Coats Island there is a new challenge:  frost boils.  These areas of silty mud are pushed up by the freezing of the permafrost below, and are extremely soft and sticky when we have to walk through them.

Walking on the tundra is always challenging, but at Coats Island there is a new challenge: frost boils. These areas of silty mud are pushed up by the freezing of the permafrost below, and are extremely soft and sticky when we have to walk through them.

 

Shorebirds keep warm in the cold arctic wind 24/7 with only their feathers, marvels of adaptation that provide them the freedom of flight and also give them the gift of warmth.  We huddle in our goose down jackets by day and sleeping bags at night, using their cousins’ own adaptation to our advantage by keeping warm with their downy feathers.  They stay active much of the long artic night, bathed in soft light from a sun that barely dips below the horizon here on Coats Island, while we sleep deeply trying to recover from each long day of work walking across tundra and marshes.

Our down bags keep us warm at night, inside our tiny cabin.  Metta McGarvey sleeps soundly while outside the winds howl, and the birds stay warm with only their feathers.

Our down bags keep us warm at night inside our tiny cabin. Metta McGarvey sleeps soundly while outside the winds howl, and the birds stay warm with only their feathers.

 

Arriving without food, the birds have only a little stored energy in the form of fat reserves that fueled their long migration and that is nearly depleted when they arrive.  But they arrive at an exquisitely timed moment, just as the snow is melting and exposing pools of water on the landscape that hatch tiny invertebrates on which the birds feed, and grasses with a seemingly infinite supply of black spiders.  We bring all of our food with us, carefully planned in advance and packaged to make cooking efficient with our small supply of fuel.  While native people have subsisted in the arctic for thousands of years, we have few skills to survive here.  If we had to feed ourselves by hunting it would take all our effort and leave us no time for the research we came to do.  So we bring absolutely everything with us, while the birds come with nothing and thrive.

King Eiders are constant companions on the tundra, where they breed in large numbers.  Like many birds, they have very warm inner feathers called down, hence the term Eider Down.  They bring their own, but we have to borrow some of theirs to stay warm.

King Eiders are constant companions on the tundra, where they breed in large numbers. Like many birds, they have very warm inner feathers called down, hence the term Eider Down. They bring their own, but we have to borrow some of theirs to stay warm.

 

During the mating period shorebirds call vigorously to stake out their territories, flying high so their calls carry farther, swooping down to walk gracefully atop muddy edges of pools to feed before taking up their aerial dance once again. We slowly plod along, stumbling over the uneven terrain and becoming mired in frost boils where ice in the ground has pushed up finely worked glacial sediments to create a sucking minefield of nearly impassable obstacles.  At the end of the day, we rub our blistered sore feet, and retreat to recover for another day.

When we band the birds, the few moments they spend in our hands give us a chance to see how truly tiny they are, and how miraculous it is that they can fly here from South America on their own power, and survive and breed in this harsh environment.

When we band the birds, the few moments they spend in our hands give us a chance to see how truly tiny they are, and how miraculous it is that they can fly here from South America on their own power, and survive and breed in this harsh environment.

 

In about a week the bush plane will return to ferry us back to civilization and we will begin the long process of sorting and analyzing our data, learning as much as we can from our short window onto the arctic life of shorebirds.  The plane will use advanced electronic instruments to navigate back to the airport in Iqaluit.  The birds will hatch their young here on the tundra, teach them how to feed themselves, and then head out on their own return trip.  On the southward leg the adults depart first; the young birds will set out later on their own, flying by instinct to a place they have never been, over terrain they have never seen.  Many will survive neither the long trip nor the return journey.  But some will, and they will carry on the dance of migration that is their genetic heritage, raising their own offspring in one of the harshest environments on earth.  We marvel at their adaptation to the arctic and to the rigors of long distance migration, and feel even more dedicated to our work helping to ensure that these birds will be able to continue their long journey through time.

The Sandpiper Nest Search

Somewhere in this photo is one Semipalmated Sandpiper nest. Searching through the vast tundra is a daunting task.

 

Our primary goal while we are camped at Coats Island is to find Semipalmated Sandpipers and equip them with tiny devices called geolocators.  These instruments measure whether it is light or dark and what time of day it is.  From those two pieces of information, it is possible to calculate your position anywhere on the globe.  If we can place the units on the birds, and if we can catch them again next year to collect the units and download the data, then we can calculate the bird’s entire migration route and wintering areas no matter where it goes.  But these are very big ifs!

This year’s task is to find and catch the birds so we can attach the units.  We come to the arctic to do this work because this is where the birds nest, and the only short period in their highly nomadic lives when they can be found in the same spot is while they are incubating their eggs.  This allows us to find both birds in a nesting pair in the same place this year and hopefully next year as well because Semipalmated Sandpipers often return to nest in the very same place.

Searching vast areas of tundra is physically challenging.  The ground is uneven and makes for difficult walking, the weather is cold with high winds that take a lot out of you, and the areas we need to cover are vast.

Searching vast areas of tundra is physically challenging. The ground is uneven and makes for difficult walking, the weather is cold with high winds that take a lot out of you, and the areas we need to cover are vast.

 

It is hard to convey in words how difficult it is to find a Semipalmated Sandpiper nest on the vast tundra.  They are exquisitely adapted to this terrain, while clearly we are not!  The first step is to carefully watch the birds.  As they display over their territories, we can begin to understand the specific places they have briefly chosen to call home.  Then we carefully evaluate the small differences in habitat to try to discern what types of tundra they prefer.  Having honed in on many areas where the birds have been displaying, we can then search more carefully by walking through the preferred areas, always vigilant with our binoculars for any sign of a bird.

After they lay their four eggs, one of the pair almost always sits tight on the nest.   Most often, we see the mate who is not incubating foraging or flying nearby and this gives us no information about the exact location of the nest.  This can go on for days.  And the walking is extremely challenging because the tundra is very uneven in some places and has mud to mid-calf in others, so we stumble and lurch our way around, watching the birds while trying not to fall flat on our faces.

Eventually we see a bird returning to the nest and we hone in on a precise location to search very closely, always being extremely careful not to step on the nest.  If we are extremely lucky we flush a bird off the nest as we wander about the tundra, which helps us locate the nest more quickly.

 

Eureka!  After much diligent searching, we have located a tiny nest hidden in the tundra sedges.  Only 40 more nests to go!

Eureka! After much diligent searching, we have located a tiny nest hidden in the tundra sedges. Only 40 more nests to go!

 

Fighting the instinct to watch the bird flying, which is the natural response to movement, we instead fix our gaze on the small area where the bird first appeared while carefully approaching.  Once we find the nest, we mark its location in our GPS, and if it has four eggs we set a small net near the nest to catch the first bird. Because both sexes incubate, we also return later and capture the mate at the same nest, guessing what their incubation schedule is and returning when it is time for the other bird to take its turn.  After we capture the birds and put the tiny geolocator units on a small band attached to their leg, we withdraw, and leave them to the work of raising their young.

We have put out 19 of the 36 geolocators we hope to place on birds here, so things have already proceeded better than they do on similar expeditions.  We have one more week to continue our work here, one of 8 camps in our network of 16 across Canada, the United States, and Russia in the Arctic Shorebird Demographic Network that are deploying geolocators on Semipalmated Sandpipers.  Our results will help us better understand whether this species is in decline—and if so how to help them—as well as the health of the wetlands throughout the entire Western hemisphere that are vital to shorebirds during their migratory cycle.

The Land is Alive

We are camped beside a small river that flows north to the coast. Like most geographic features in remote arctic wilderness areas, the river has no name.

 

Something was flopping on the tundra like the arm of a fur coat in the persistent Arctic winds.  It was not a live animal, but the gray form stood out in texture and movement from the low arctic vegetation around it.  I walked the edge of partially frozen little pond to get a better look.  It was the billowing remains of what had been a king eider nest.

The female Red Phalarope is one of the most striking shorebirds on the tundra.  Unlike most bird species, the females are more brightly colored, and the males tend the nest.

The female Red Phalarope is one of the most striking shorebirds on the tundra. Unlike most bird species, the females are more brightly colored, and the males tend the nest.

 

The undulating arm that had caught my attention was actually thick belly down from the female eider.  She had pulled the down from herself to line the nest before laying her clutch.  It had been holding her four eggs off of the still frozen ground and against her belly, keeping them perfectly insulated.

A young Arctic Fox shedding his fur.  This photo was taken by Brad Winn during his Arctic trip last summer.

A young Arctic Fox shedding his fur. This photo was taken by Brad Winn during his Arctic trip last summer.

 

The night before I found the nest, the wind had carried a wisp of eider scent to the nose of an Arctic fox.  That’s all it took.  With a nose more sensitive than a bloodhound’s, the fox moved up the stream of air until he found the source: the sea duck and her eggs.  Eiders are strong ducks, and the female had evaded capture, but not her eggs.  Each was lifted carefully from the bed of down and quickly cached by the fox within yards of the nest.  Without the heat of the down and the incubating adult eider, the eggs would stop developing and the embryos would die.  Now they sit, future self-contained protein meals for the fox, preserved by the cool tundra and neatly tucked away.

Despite their tiny size, Semipalmated Sandpiper males engage in fierce struggles over territories and females.  These two birds had an epic battle that lasted for half an hour, and were so focused on each other that Brad was able to take these remarkable photos.

Despite their tiny size, Semipalmated Sandpiper males engage in fierce struggles over territories and females. These two birds had an epic battle that lasted for half an hour, and were so focused on each other that Brad was able to take these remarkable photos.

 

The essence of the arctic landscape, including Coats Island where we are now at the top of Hudson Bay, is the store of innumerable clues of nature hidden within its vastness.  Like the batten of eider down, we encounter evidence of stories that could be unfolding as we watch or decades old.  Examples include a set of moss-encrusted antlers sticking straight out of the ground where a bull caribou had been pulled to the ground by wolves nearly 30 years before.  Or today, footprints across the silt of a quiet pool show where a pair of snow geese walked just hours before as they searched for small mats of algae locked in receding ice.  The land is alive, and we are extremely fortunate to be here to read all of its stories.

After sorting out their disagreement on the boundaries of their territories, the birds settle down to recover and then set off to find a few precious moments to feed on invertebrates that are hatching in the short arctic spring.