NOAA Teacher at Sea
Aboard USCGC Healy
August 7 – 25, 2018
Mission: Healy 1801 – Arctic Distributed Biological Observatory
Geographic Area: Arctic Ocean (Bering Sea, Chukchi Sea, Beaufort Sea)
Date: August 20, 2018
Evening of August 20 – North west of Barrow Canyons, Beaufort Sea
Air temp 28F, sea depth 1914 m, surface sea water temp 31F (72.5N are furthest point north)
Walrus and Polar Bears on Ice
In the last couple of days we have seen two of the Arctic’s most notable mammals on the ice, the walrus and the polar bear. Below is a picture that I took of a large group of walrus that floated near the ship on the evening of August 19th.
These walrus were just the beginning of an even larger group floating up on the ice. Walrus like to rest on the ice in between feedings off the ocean floor. Walrus will eat many items off the shallow sea floor, this location is about 60 meters deep. Their favorite foods are bivalve mollusks, including clams. The walrus will not break the clams’ shells but suck out the food with their powerful suction capabilities. More terrifying is that the walrus will occasionally do the same to some sea birds and seals. Walrus have relatively few teeth besides their tusks. If they catch larger prey such as a bird or seal, they will suck out the good parts just like a clam. Male walrus can grow up to be over 4,000 lbs. Add these facts together and these cute animals become a little more frightening.
Walrus are common in the northern Chukchi Sea this time of year and typically have been known to migrate south in the winter. In a science presentation held onboard our ship, marine mammal scientist, Catherine Berchok, shared acoustic data from her moorings that documented recordings of walrus in the northern Chukchi Sea in the winter. Previous surveys have not typically recorded a presence of walrus in this region as usually these mammals need a mix of ice and open water for feeding, though they can break through winter ice for breathing. Scientists now have additional questions for further investigation. Why are these walrus here in the winter? Have the walrus changed to a seal diet? These are questions that are still unanswered.
On the evening of August 17th, we came across a large group of walrus (see image above). Scientists specializing in mammal and bird observation were estimating the amount of walrus we observed. Each of the dark blotches on the ice in the fog were all groups of walrus. The larger groups contained 50-80 walrus while the smaller ones were around 20. Standing high up on the bridge with cameras and powerful binoculars mammal observers, Jessica Lindsay and Jennifer Stern, estimated the total number to be around 1200 walrus!
Finding Polar Bears
From high up on the ship’s bridge (shown in the above picture), mammal observers and bird observers armed with binoculars are always present in daylight hours when the ship is moving. Bird observer Charlie Wright has quite the trained eye for spotting birds and also polar bears. A couple days ago he spotted a polar bear approximately 4-5 miles away. While looking through binoculars, all I could see was a tuft of fur, and then only when I was told where to look. To me it was like, finding a polar bear in a snowstorm. Last night Charlie spotted another one. The polar bear pictured above was much closer, perhaps a mile away. At first, we observed the bear curled up on the ice, but then it stood up and walked around. The light was dim and the weather was foggy during my observation, but if you look closely at the picture you will see that the bear looks quite plump after a spring and summer of feeding.
Today’s Wildlife Sightings
Normally I would focus on a bird, fish, or mammal in this section, but since I focused the entire blog on mammals I want to take this opportunity focus on snow sightings. We are now actually in one of the drier places on earth. Even though it seems like it is always cloudy and foggy usually only small amounts of precipitation fall here. Temperatures have been below freezing for a couple days and we have experienced some snow showers but they do not last for long. Overnight it was enough to dust the Healy with snow as shown below. Either way I cannot say I experienced snow in mid August before!
Now and Looking forward
We will be leaving the deep Arctic shortly and heading south through shallow seas towards our last study area. Along the way the number of whales, walrus, and birds may increase along with the increased food supply from the shallow sea floor.
On a sad note that means we are leaving the ice and headed south. So I leave the ice by sharing with you this picture. Though it was dim light and a bit fuzzy I saw a walrus on its back soaking in the Arctic weather by its ice beach umbrella.