Hatched! So far, so good for the 2018 chicks on Cooper Island

August 11, 2018:   Field report

Hatching is finally over with one very late egg hatching today after having been incubated for 34 days; 28 days is normal.  The oldest nestling is 16 days old; the chick is gaining weight and doing well like all of the other 45 nestlings.

While the main pack ice is well offshore, the Marginal Ice Zone, where ice covers from 18 to 80 percent of the ocean’s surface, extends south to the entire Alaskan Beaufort Sea coast, including Cooper Island. The seascape visible from the north beach now has widely scattered floes, some with rather high vertical relief breaking the horizon, in a nearly flat calm sea. This differs greatly from what was present last year when the first week in August had no ice visible with large swells breaking on north beach. More importantly, last year at this time the sea surface temperature was well above 4 degrees Celsius while this year it is less than 2 degrees Celsius. The guillemot’s preferred prey, Arctic Cod, are typically found in waters from -2 to 4 degrees.

The ice and water temperature conditions are ideal for the parent birds provisioning. Arctic Cod has comprised well over 90 percent of the prey being fed to chicks this year. The two oldest chicks, hatched on July 21, weighed 35 grams at hatching and now weigh 275 grams and 245 grams – the larger of the two experiencing an almost seven-fold weight increase in a 15-day period. A growth rate that rapid requires readily available prey that is both abundant and high energy, as well as two dedicated parents to return to the nest site with a fish every hour. Similar high growth rates are occurring at other nests.

Read the rest of the field report at Proteus.

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First chicks of the 2018 season

August is the rainy month of our field season, and the first day of the month was tough for us. During our morning nest checks, it wasn’t easy to keep our hands warm in a steady soaking rain, coupled with a windchill of 27 degrees Fahrenheit.

The fingerless gloves I wear daily in the summer are a godsend for handling eggs and nestlings–wet fingerless gloves at temperatures near freezing are only slightly better than no gloves at all.

The cold, wind and rain (and numb fingers) were made more bearable by the fact that our nest checks found hatching high at nests that are still being attended. All the chicks seem to be doing well in their first few days.

Read the full field report on Proteus.

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2018 Census

In this week’s field report, George talks about specific birds as well as the overall report of his 2018 Black Guillemot census on Cooper Island.

Nature, when observed or monitored for any extended period, typically provides a predictability that is reassuring in its consistency and sufficient surprises to keep one engaged.

For over four decades, my first task after I set up camp was a census of the Cooper Island Black Guillemot colony. This year was an excellent example of this balance of the expected and unexpected.

Read more at Proteus.

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