New York Storm-Petrel Madness

It was bit of a bumpy ride out to "The Tails" (north end of Block Canyon) on the night of July 31st. The seas were a bit unsettled but the offshore forecast for the following day, 8/1, was of favorable conditions with light wind. It was roughly 3:00 AM when Captain John Shemilt, Angus Wilson and I arrived along the western edge of The Tails. It was a moonless night and we spent the leading hour slowly navigating our way through the pitch black, playing close attention to the radar and watching for lobster pots. The moonless night added to an incredibly enhanced sky with stars brilliantly twinkling in every which direction. The pre-dawn sun light eventually began to make an appearance on the horizon but not before we situated our trawling rigs and communicated our morning strategy.

The plan was to lay down a chum slick composed of menhaden oil and cubed suet, trawl around the canyon for game fish and routinely circle back to check on the slick. Sea conditions were perfect, tiny amount of swell but completely glassy on the surface. We laid down our slick at about 4:45 AM and began to work the trawl. No hits yet and a small number of Wilson's Storm-Petrels buzzed by the boat, likely headed to where we put down the chum. We eventually circled back and soon noticed a flock of Storm-Petrels pattering on the surface. They had found the slick and didn't take long for Angus to quickly spot a WHITE-FACED STORM-PETREL rapidly "pogoing" along on the edge of the slick. Lighting was still minimal but the repetitive kicking and sailing feeding behavior easily separated the White-faced from the Wilson's Storm-Petrels. Pelagodroma, the genus name for White-faced Storm-Petrel, means "sea running" and this is clearly evident in the birds behavior. To our luck, the White-faced decided to head straight at the boat, briefly lending itself to some record photographs. This bird would eventually be driven off by a commercial vessel who repeatedly pounded our slick after mistaking it for a natural one. White-faced Storm-Petrel is a rare, non-breeding visitor in Atlantic waters (North Carolina to New England) and is most often found inshore of the gulf stream within canyon lands.
Risso's Dolphin @ Block Canyon
We continued to fish the canyon for a bit longer and eventually started heading a bit west toward the Middle Grounds. A pod of RISSO'S DOLPHINS made a few appearances. Always good to have our cetacean friends nearby, a good indication of sea life in the area. Sure enough, we'd eventually pick up an Albacore Tuna while working the trawl through the Middle Grounds. The next round of excitement came from a small black & white shearwater off the bow of our vessel. The AUDUBON'S SHEARWATER glided past us and eventually put down on a small mat of sargassum weed, a favorite foraging feature for this species where they can easily locate and dip for small fish that are attracted to this offshore weed. Superficially similar to the more commonly inshore spotted Manx Shearwater, Audubon's structurally differ by having a lighter build, longer tail, with dark under tail coverts and seemingly shorter/broader winged with usually a bit more white on face. In light wind, Audubon's glides more buoyantly than Manx with a lower more fluttery flight. We would eventually spot two more Audubon's Shearwaters, which were three of a measly 5 total individual shearwaters that we would spot during the entire day (2 Great Shearwaters later on). Where were all of the shearwaters? We normally pass several Cory's during our trek back to the mainland but not a single one throughout the entire trip.


Little did we know the excitement had only just begun. We set our course for the south and toward the Rabbit Ears at Ryan & MacMaster Canyon in our continued search for fish and other deep sea life. We encountered a couple of LEACH'S STORM-PETRELS just north of the canyon ledge and proceeded to set another chum slick, this time consisting of a large Mackerel block and a couple of my frozen experiments (ground beef fat mixed with ground Butterfish, whole Shiners and infused with Menhaden oil). There were very large mats of sargassum dispersed throughout this canyon, something interesting had to be in here. We picked up a small Mahi Mahi while trawling through the weeds and soon thereafter kicked up two BAND-RUMPED STORM-PETRELS right off the bow of our vessel. Captain Shemilt predicted there would be more Band-rumpeds working our slick and he was spot on (he also predicted the White-faced Stormy from earlier in the day). Frustrated with all of the weeds we ended up pulling in our lines and spent the next hour plus studying and photographing 8-10 BAND-RUMPED STORM-PETRELS that we found in our chum slick, along with the expected 80+ Wilson's Storm-Petrels. The Bandies obliged us with excellent views and photo opportunities as they buoyantly glided and flew about the slick, sometimes at great speed and with more authority in comparison to the nearby Wilson's. A worn Leach's Storm-Petrel paid us a visit while we were studying the Band-rumpeds which was fun to have as a side-by-side comparison. 
Band-rumped Storm-Petrels breed on select islands off the coast of NW Africa and Portugal and are rare, non-breeding visitors here in Atlantic Waters where they wander about the gulf stream and usually just beyond the continental shelf. Also in the slick were the two Great Shearwaters that I had mentioned earlier in the post. Amazingly these would be the only two Greats that we saw the entire trip! Several passes, and plenty of photos later, we decided it was time to split and head back north to do some trawling at "The Dip." As we cruised north we noticed an extremely athletic pod of dolphins, effortlessly leaving the ocean surface and putting on a quick but entertaining aerial show. The STRIPED DOLPHINS disappeared beneath the surface and never did return for photos.  We arrived at The Dip and it was here where we'd catch a beautiful White Marlin, likely in the 80 pound range, that was lit up in color. Usually these game fish will lose a little bit of their brilliance and their overall tones fade out by the time you get them to the boat. This was not the case as we managed to the get the Marlin alongside the boat fairly quickly and John hoisted the fish into the boat by its bill. Struck by its beauty, Captain Shemilt decided it was only right to release this fish back into the ocean.  


White Marlin                                                            Photo by Angus Wilson
The end of an excellent day exploring the edge of the continental shelf. It was a day of quality over quantity and we weren't complaining. Here a few additional photographs of Band-rumped Storm-Petrel taken in our slick at Ryan & MacMaster Canyon:

This bird showing a weak carpal bar, typical of Band-rumped Storm Petrel.
Also of note is the obvious wrap-around of white band on rump, slightly
concave tail but more or less square tipped (variable depending on viewing
angle and subspecies), long wings held relatively straight rather than crooked
like Leach's

Poor lighting but note the extensive white wrap-around of rump band. And
again the square shaped tail (not deeply forked like Leach's) with long
wings and legs tucked within, not extending beyond tail tip like Wilson's. 

Fresh individual with a full set of primaries and rectrices. Caution needed
when separating subspecies but overall size, tone and molt timing seems
consistent with Grant's. This bird showing a relatively pronounced carpal
bar but still with a square tail, not forked like Leach's, and a wide, even
wrap-around white rump band. 












Comments

  1. Nice write up. I bet that those birds loved your chum slick.

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