August 22, 2005
What exactly are "big eyes"? The big eyes are powerful binoculars mounted on the deck of the flying bridge. The flying bridge is the bow's top deck which is above the Jordan's bridge. The big eyes are used by the mammal observers. There are six mammal observers on the cruise. They work in 40 minute shifts with three observers working at the same time. One mammal observer watches for cetaceans on the port side and one watches on the starboard side. These observers are responsible for a 90° angle beginning at the bow, and then heading left or right depending on which side they are responsible for. The third observer watches the entire 180° field and also enters data into the computer when cetaceans are spotted. There is also an independent observer on the flying bridge who watches the entire field of view, but the IO cannot reveal any cetacean sightings until they pass the 90° field of the port and starboard observers. The IO is actually recording the sightings the main team misses. After the forty minute shift, they rotate positions, with one of them being replaced by a new observer. The person relieved gets a two-hour break until starting the rotation again. The watch starts at sunrise and ends at sunset.
There are four big eyes mounted on the flying bridge. These are large 25X binoculars, and the observers scan back and forth over their field looking for signs of cetaceans (blows, breaches, fluking, etc.). I missed the first sighting of the day, a humpback whale, but soon after I arrived on the flying bridge, the fun began. Laura Morse was the mammal observer on the port side and soon yelled, "I have a blow!" Next she stated the angle of the cetacean. This number is on the base of the big eyes. She then says the reticle of the animal. This number indicates the distance from the ship. Then Laura gave the course of the cetacean relative to the vessel and estimate the cetacean speed in knots. While Laura was communicating this information to everyone on the flying bridge, the observer responsible for the data entry immediately recorded this information into the computer. The computer system allows the scientists to can keep track of the animal sightings.
Everyone was watching and waiting for the next sign, and with the next set of blows, dorsal fins were spotted. It turned out to be a pod of killer whales! Six in all: two males, two females, and two young. Killer whales (Orcinus orca) are identified by the shape of their dorsal fin and saddle patch. Individuals can actually be determined by these characteristics. The male tends to have a taller, erect dorsal fin while the female's is a bit smaller and a little rounded at the top of the fin. What a find! We watched the whales for about one hour, photographing them for individual identification.
Soon after the killer whales, we observed some Dall's porpoises riding our bow. They are actually riding a pressure wave created by the bow of the boat. A Dall's porpoise (Phocoenoides dalli) is from 1.7 - 2 meters in length and has a robust black and white body with a little bit of white "frosting" on a black dorsal fin. It was such a pleasure watching them maneuver so closely to the ship!
Today was the second day we saw humpbacks, but today's sighting was extremely memorable. After sighting the blows, they were quickly identified by the dorsal fin. This fin is located on a hump that is noticeable when the whale arches its back during a dive. The humpback is the best studied of all the large whales due to the fact that they can be easily identified by markings of their flukes. We followed the humpbacks for almost an hour, enjoying spectacular sights of their pectoral fins. The pectoral fins are about one-third of the whale's body length. The underside of the flippers are white, making them very visible when the whales swim close to the surface. However, the white appears an aqua-blue color due to the coloration of the water. It is very easy to keep track of the humpbacks' position as they swim just under the water's surface. These humpbacks swam within fifty meters of the ship, close enough that I could smell their breath! It surely was not a pleasant odor!
Our last sighting of the day was a pair of fin whales (Balaenoptera physalus). Fin whales are the second largest animal in the world, only a few meters smaller than the blue whale we saw yesterday. A unique characteristic of the fin whale is its asymmetrical pigmentation of the lower jaw (right side is white, left is black). After a few more observations of these fins, they left the area. What an incredible way to end the day!