Arctic, Expeditions and Travels

Knot Plateau

Prior to this trip, our last expedition to the Arctic was over five years ago. At the time, filmmaker Allison Argo was in the middle of producing the documentary Crash: A Tale of Two Species for the PBS series Nature, and we brought her to the site we thought would provide us with the best chance to see red knots. It had been ten years since we had visited that particular region, and we were eager to resurvey the area. But the knots were nowhere to be found.

We ruminated about the sad fact that the Arctic had been depopulated of this wonderful species not because of any problem in the Arctic, and not because of global warming or some other worldwide problem, but because people in the US have traded reason for greed and nearly decimated horseshoe crabs. We pulled one thread in the complicated ecological fabric of this magical species’ life history, and within ten years red knots were nearly undone.

A shattered rock field. Similar features can be found throughout this region.

A shattered rock field. Similar features can be found throughout this region.

Fast forward to today. The problem of horseshoe crab overharvesting in the US is heading towards resolution, so now the question is: where are the remaining knots? The data suggested the habitat was right on our plateau, and we had found a high density of knots with transmitters in this region in the past – but were the knots still using it?

Our camp here is spartan. We had to jettison many of the luxury items, like the cook tent, so that we would need to make the 25-mile ATV trip into the plateau only once. Even then, the ATVs were overloaded, and we had numerous problems like flat tires and a cracked support for the back rack. But at long last, after nearly a week of battling mud, water, and the elements, we had finally arrived. And we knew we had come to the right place. Within a few hours of our arrival, two knots sounded the territorial call “poor me poor me poor me” – an auspicious sign for the days to come.

Josh's skills have proven invaluable, as he has been called on to repair our ATVs multiple times. Here, he fixes a slice in an ATV’s tire from a sharp rock.

Josh’s skills have proven invaluable, as he has repaired our ATVs multiple times. Here, he fixes a slice in an ATV’s tire from a sharp rock.

After two days of exhausting survey, we were relieved to find the number of knots at least equal to the high densities we saw years ago. In our earlier surveys for knots, we had searched eskers, which are long gravel bars formed by rivers running under glaciers. We saw about one pair of knots per linear kilometer of esker, and with mostly unsuitable-for-nesting wetland surrounding it, we concluded the population density was one per square kilometer.

But here at knot plateau, the amount of potential nesting habitat is far greater because while the knots still nest on high ridges, like eskers, they do so in much greater profusion. It’s perfect nesting habitat because these potential nesting sites are surrounded by wetlands where the newly-hatched young can feed. The complex is also within 10 kilometers of the Sutton River basin. The river remains clear almost year-round, making it a perfect feeding spot for the adults while the nesting area is still frozen.

A typical ridge nesting habitat on knot plateau.

A typical ridge nesting habitat on knot plateau.

We have surveyed two areas so far and have found about 6-7 knot territories that are roughly 1 kilometer apart. But the area of potential habitat is so great that we may possibly end up with a much larger number of knots.

The greater area of habitat, however, causes great difficulty in finding nests. It doesn’t help that knot nests are the most difficult to survey of any shorebird. Most shorebirds react to intruders on approach because both adults stay near the nest. Knots, on the other hand, don’t react to intruders because one adult is elsewhere feeding and the incubating bird won’t leave the nest until he is almost stepped on. So far, we have found the nests of golden plover, semipalmated sandpiper, dunlin, as well as those of other species like long-tailed jaegers – but so far no knot nests.

A golden plover nest.

A golden plover nest.

The knots are almost devious. Yesterday we had two knots calling and one dropped to the ground and stayed in position. We approached gingerly, assuming we had found a nest. We searched while the bird stayed within 50 meters. But then it flew away. We searched the surrounding area but couldn’t find a nest. We had been duped.

This points to another difficulty we face. We decided to survey the Arctic at this time so we could search for adults with broods, as opposed to surveying earlier and searching for knots with nests of eggs. It is easier to find knots after the eggs hatch, because the adult will react at a considerable distance and will stay with the young. This year the hatch is late, so we are in the bridge period when some birds may be with broods and others on nests. The bird yesterday may have had a newly hatched brood and behaved differently than if it had a nest.

Predation defines all populations in the Arctic, and two of the chief predators are the Arctic Fox and jaegers. Here, an Arctic Fox is mobbed by a Long-tailed Jaeger whose nest is close by. Both predate chicks from newly-hatched shorebird nests.

Predation defines all populations in the Arctic, and two of the chief predators are the Arctic Fox and jaegers. Here, an Arctic Fox is mobbed by a Long-tailed Jaeger whose nest is close by. Both predate chicks from newly-hatched shorebird nests.

All these complications are minor compared with the achievement that we may have found a superior knot habitat and a robust population of knot. With four more days remaining in our trip, we may have yet to find the knot nests we came for, but we cannot help but be pleased by what we have already found.