ARCTIC PROGRAM UPDATE – August 2005, Pituffik, Thule, Northwest Greenland
— 1 September 2005
— in Arctic Program - Greenland
Harp seals on pack ice in Baffin Bay
Since my arrival on 23 July we have enjoyed unusually calm weather allowing a great deal to be accomplished in a shorter than usual number of days. Just prior to my arrival a storm with high winds (100+ mph) passed through the area. Since then the only climate-related challenge is pack ice that is remaining longer into the high arctic summer than usual. There are still large ice flows in Baffin Bay but most are to the south of us and causing limited navigation problems although we were stopped by impassable ice a few days ago. A positive related to the pack ice is seeing many seals. Yesterday we saw three (ringed seal, harp seal, and bearded seal) of the four seal species that occur here. The presence of the pack ice is credited to heavy snowfall this past winter resulting in thicker ice taking a longer time to break up and melt.
Measuring and banding an adult Gyrfalcon
Another possible event related to the heavier than usual snowfall is several of the Gyrfalcons appear to have switched to using different/alternate nest sites. Sites known to have been used for many years are abandoned. Possibly when the Gyrfalcons were preparing to breed in late April their nest ledges were snow covered so they used more snow-free alternate nesting locations. Until the molted feathers we are collecting at nest sites are analyzed genetically, we cannot be certain the Gyrfalcons we are seeing in 2005 are the same falcons as from nearby 2004 nest sites. The information from the feathers will also help us understand the probable adult survival rate between years. Both the genetically confirmed identity of breeding pairs using alternate sites and adult nest site turnover rate will be unique information for Gyrfalcons. A drop of blood/DNA from nestling falcons provides similar information to the molted feathers (assuming you find molted feathers from both adults) but we were too late in the season to collect blood from Gyrfalcon nestlings. All the young were so old that climbing into the eyries would have caused premature fledging and possible injury of the nestlings. At most of the Gyrfalcon nest sites we have visited, the young have been flying for about a week.
Although the Gyrfalcons have probably moved about, the Peregrines still defend and nest on their traditional cliffs. Most Peregrine young are now about two weeks old. Peregrine reproduction looks good again this year.
In total, we visited 14 of the 15 known and new Gyrfalcon nest sites in northwest Greenland. At least eight produced a minimum of 17 flying young, and adult Gyrfalcons (or their recently molted feathers) were found at three other locations. For Peregrines, we visited all six of the locations they have been known to breed and all had pairs present with five producing two to four young. We surveyed other potential falcon nest sites traveling 1,497 miles (according to our GPS) by boat in the process.
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