We are currently (1100, 25 July) in the southern portion of the Drake Passage (-61° 04.48S; -67° 42.97W), steaming on a southerly course at about 10 kts. Seas are rough and driven by sustained westerly winds of about 30 kts, with gusts up to 40 kts. The air temperature is about 0.9°C, although earlier in the morning it was below freezing. The skies are partly cloudy with some occasional light snow in squalls that pass by.
The 24th of July was a steaming day at an average of about 10 kts. Winds were a steady 20-30 knots out of the west-northwest and seas were 8-12 feet from the same direction. The skies were mostly clear, with occasional snow showers. There were no scheduled over-the-side sampling activities because we were within Argentina's 200-mile limit for the entire day. There were, however, bird and mammal observations made during the daylight hours as reported below. Others in the scientific party worked to finish setting up the laboratory experimental equipment and the Raytheon technicians continued to set up the CTD and MOCNESS systems for a test deployment scheduled for mid-day on the 25th of July.
Marine mammals, especially whales, are being surveyed by Ari Friedlaender and Rebecca Pirzl. Ari reported that, considering our position and the time of year, viewing conditions were quite acceptable. As the afternoon wore on, viewing conditions became better, as winds slacked slightly. Around 1200 local time, three orcas were seen passing the bow of the ship at 200 meters. The group included at least one large male and one large female. The animals were porpoising through the swell and were then seen chasing two sperm whales that surfaced in front of the orcas. The scene was viewed for 10 minutes, as the whales moved off to starboard. Several blows were seen from the sperm whales, and the orcas were seen multiple times porpoising and splashing in the same area as the blows. Approximately 10 minutes later, two more orcas crossed the bow of the ship at a distance of 100 meters. A single large male slowed and surfaced in the swell 50 meters directly abeam of the bridge and remained in the swell for several seconds, before both animals porpoised away in the same direction as the other animals. Noontime position and position of the sighting: 57° 16.62S, 65° 53.26W.
Later in the afternoon, at 1446 local time, two southern bottlenose whales surfaced 50 meters off the starboard bow. The animals were swimming away from the ship and were seen quite clearly from a fine angle above. The animals were dark tan, approximately 7 meters in length, and had small triangular dorsal fins set far back body. The light colored, bulbous melon of one animal was clearly visible under the water before both animals sank away from view. Position of the sighting: 57° 41.16S, 66° 04.06W. While southern bottlenose whales are not uncommon in and around Antarctic waters, it is rare to get such a good view of animals at such close range.
The occurrence, abundance, and diet of marine sea birds are being studied
by Chris Ribic and Erik Chapman. Although, the "official" survey will not
start until we get to the SO GLOBEC study site, they have been making observations
Here's their first installment of daily bird summaries for NBP01-04.
We observed birds from the bridge as we traveled through the northern portion of the Drake Passage. Observation conditions were excellent, although we had to get used to seeing birds in direct sunlight, conditions we didn't experience often on the last cruise. The Drake is usually somewhat of a bird desert, still, we saw good abundance and diversity today: Here's the species list:
Common Name | Scientific Name |
Wandering Albatross | Diomedea exulans |
Grey-headed Albatross | Diomedea chrysostoma |
Black-browed Albatross | Diomedea melanophris |
Southern Giant Petrel | Macronectes giganteus |
Southern Fulmar | Fulmarus glacialoides |
Cape Petrel ('Pintado Petrel') | Daption capense |
Blue Petrel | Halobaena caerulea |
Broadbilled (Antarctic) Prion | Pachyptila vittata (des.) |
Thin-billed Prion | Pachyptila belcheri |
Sooty Shearwater | Puffinus griseus |
Unidentified Diving Petrel | Pelecanoides sp. |
Cheers, Peter