It’s been an eventful week out here on the briny deep! We have gone all the way from Honolulu (again) and tomorrow morning we will be at Midway, which is basically the entire length of the Papahanaumokuakea Marine National Monument. For the first half of the week we were N of the islands in a part of the ocean with a deep thermocline and not much productivity. We were still averaging 1-2 sightings a day, but it certainly was not super mammal action. Luckily the bird life was pretty non-stop, with the wedge-tailed shearwaters being the stars along with Cook’s and Bulwer’s petrels, the odd booby, frigates, and others. Dipnet stations were also held most nights and the mighty myctophid (or “McLovin” as one of our scientists likes to call them) was once again the most common catch. The highlights of the week were the largest sperm whale I’ve ever seen, an entangled green sea turtle rescue mission, and a fresh-dead Kogia (the jury’s still out on sima or breviceps) that was getting munched on by some large sharks. We pulled the carcass on board and performed a necropsy on the deck. Good times!
Halfway through the week our mission changed from Pac-Manning down the trackline to two days of intensive surveys around Pearl and Hermes Atoll, and it was here that our action started getting hot and heavy. The weather on the first day was still fairly windy and choppy as we circled around the atoll (you can see the reflection of the green lagoon in the clouds above it) but we had numerous beaked whale sightings right off the bat, including some confirmed Ziphius cavirostris. Beakers are super hard to spot in rough water and are so cryptic and stealthy that getting a good look at them is nearly impossible, but we managed to pull it off. It seemed like everywhere we looked we’d find beakers. Unfortunately most of them went down as Unids, but it was still great to get to see them. We also had a nice group of bottlenose dolphins come over for a photo and biopsy session but the rough-toothed dolphins were a bit more aloof.
The second day was a bit calmer and we decided to keep circling the island in the hopes of getting our experimental B.U.R.P. (biological underwater recording device) to record some of the beakers. Once again our sightings were mostly unid. Ziphiids, unid. mesoplodons, with the odd sighting confirmed to species. I spent the latter half of the day in the small boat and during our watch we found a glass ball, but the super highlight was when a group of ~7 mesoplodons surfaced more or less right in front of us. The five people in the boat went into super pandemonium action mode; you’ve never seen cameras and crossbows get readied quicker. We only had about 90 seconds of surface time before they dove but we were able to get some somewhat decent shots. Unfortunately, our one biopsy attempt fell short and we weren’t able to get photos of an adult male, so we’re still not sure what species. If anyone out there has an idea what they are, let me know! We ended that day with another group of bottlenose dolphins at sunset which gave up numerous biopsies from the ship and the small boat.
The bird life is quite dense around the islands as well, with white and sooty terns, black and brown noddies, tropicbirds, frigates, shearwaters, boobies, and various petrels everywhere. The red-footed boobies are especially fun to watch chase flying fish flushed from the bow of the ship. If there’s a frigate, jaeger, or skua around, it will usually swoop in and make sure the red-foot barfs up its catch.
After two days of fun and games around Pearl and Hermes we pointed our ship towards Midway. The weather on this one-day transit has been excellent and we had numerous beaker sightings, but the ultimate score was a group of four killer whales right before sunset. We launched the small boat to try and apply a satellite tag but the whales vanished as soon as the boat hit the water. These tropical killer whales are super sneaky and we never saw them again. Oh well…. “valiant effort” is beginning to be the catch phrase of the cruise.
That’s about it for this week. Tomorrow we hit Midway.