Wednesday, June 27, 2018

Spring 2018 Wrap Up by Brian Patteson

This was our 12th Spring Blitz aboard the Stormy Petrel II and for the first time in many years we did not miss any trips because of weather!  We ran a kick-off trip on May 19 and then began daily trips on May 23, ending on June 9!  This run of 18 consecutive day trips was second only to the 19 straight days we ran in 2009!  Going every day gives one a good perspective on how the ocean is constantly changing.  Subtle differences in local wind direction and current flow from one day to the next have a bearing on what we find.  It's also complicated by other factors well to the south and east of Hatteras.  Prior to the "Blitz" we had an extended period of southerly winds with fewer shifts to the north than we get during this period some years.  Although we did not get the strong westerly flow that prevailed last spring, we didn't get much easterly flow either, so overall the weather had a negative impact on diversity.  Easterly flow is key for seeing lots of South Polar Skuas and all three jaegers.  It is also good for Trindade Petrels and Arctic Terns.  We had a few of the latter early on, but I think most of that flight was out around Bermuda this spring.

The conditions did not seem to affect the more expected species as much, however.  We had a good showing of Black-capped Petrels, and our lowest counts of 11 and 22 were a far cry from the single digit counts we've had a few times when the Gulf Stream took a queer turn.  The Gulf Stream has done just that a few times this winter and spring, and on some days the water out in the deep was greener than usual.  The Leach's Storm-Petrels didn't seem to mind this green water, however, and we saw a total of 142 on ten trips in May with a hight count of 55 on May 30.  We also had some rainy weather in late May and that did not deter the Leach's Storm-Petrels either.  Band-rumped Storm-Petrels were found in modest numbers, and the majority that we saw were molting winter breeders.  We also saw some sharp looking Band-rumps that we surmised were summer breeders.  As far as the AOU or ABA checklist is concerned these are all the same, but more likely these are cryptic species that will remain a challenge to identify at sea.  Scopoli's Shearwater seems to be a more likely split here in the near future and we spent quite a bit of time looking closely at the Cory's type shearwaters feeding in our chum slicks.  From late May onward, a steady procession of Great Shearwaters were nice to have around for sorting out the Cory's.  Cory's Shearwaters (the Atlantic breeders) are larger (but not heavier) than Great Shearwaters, while Scopoli's Shearwaters, which nest in the Mediterranean, are smaller than Great Shearwaters.  Sexual size variation complicates the Cory's/Scopoli's ID a bit though and the parameters for ID by plumage are still being worked out.  One thing we've noticed though is that Scopoli's are pretty consistent boat followers when we are chumming.  They also seem to predominate in the deeper waters.  Audubon's Shearwaters made a better than usual showing this year and I think this is because we had so many days with southerly winds and also because Sargassum - their main foraging habitat - was abundant most days.  Wilson's Storm-Petrels, on the other hand were in lower than usual numbers.  This was about the 3rd year in a row with only about 100 or so Wilson's per trip average.  Last year, I figured numbers were off because of westerlies.  This year, and perhaps also in 2016, it was because of southerly flow.  We tend to see more Wilson's Storm-Petrels when the wind is against the current and both southerly and westerly wind is with the current.  Nevertheless, Wilson's Storm-Petrel was the most numerous species on all but two trips, which were days with good counts of Audubon's Shearwaters.

Rare tubenoses in spring 2018 were just that - rare.  We had Trindade Petrels on just a couple of trips, both in May.  We did not see a "Fea's" Petrel until June and we only had a couple that showed well close to the boat.  The bird we saw on June 2 was a small one and we wonder if perhaps it was of Cape Verde origin.  The bill looked too thick at the tip for Zino's, but too fine for perhaps even a female Desertas Petrel.  Tracking data suggests Cape Verde Petrels don't come here that much, but researchers have only followed adult birds.  Desertas Petrel and Cape Verde Petrel are another pair the AOU and ABA has yet to deal with.  Some authorities have split them as cryptic species.

Tropicbirds are not cryptic but we did a double take when two tropicbirds appeared overhead during the morning of May 26.  Our first impression was there was a big one and a small one and sure enough we had a short-tailed immature Red-billed Tropicbird and a long-tailed White-tailed Tropicbird appear at the same time.  This is only the second time we have seen this in 25 years of spring trips here!  Red-billed is usually the spring tropicbird, but this year we also found a White-tailed Tropicbird on May 19 - very early for this species!

I was hoping daily coverage in early June might net us another Swinhoe's Storm-Petrel but it was not to be.  Of four that we have seen off Hatteras, three have been found in the first ten days of June.  We did get a European Storm-Petrel on June 1.  European Storm-Petrel is looking like another future split.  Formerly know as British Storm-Petrel, it was renamed because of the population that breeds in the Mediterranean.  Now it looks as though they are distinct.  Presumably the birds we are seeing once or twice most years are the more wide ranging British Storm-Petrel.  We did not see a Bermuda Petrel this spring, but we did luck out with another rare petrel.

On May 29, we had just gotten out of some heavy rain and were in the process of attracting birds to a new slick when Peter Flood spotted a different looking petrel he initially called in as a light Trindade Petrel.  He soon recognized it as something different, but it took a few minutes to figure it out as the bird left the slick about as quickly as it had come in.  Conventional logic had us thinking Atlantic Petrel, which would have been a first for the western North Atlantic and way out of range.  But the straight wings and size and shape of the bill made us realize we had seen a TAHITI PETREL, which was even less expected here.  As far as we know Tahiti Petrel had not yet been recorded in the Atlantic Ocean, and it was definitely not on our radar.  None of our crew had seen one before but the big bill and overall structure was familiar to us from books, and we got some good photos of our bird.  In size it was similar to a nearby Black-capped Petrel so that eliminates the even more remote possibility of the smaller, but similar Beck's Petrel.  Beck's is about the size of a Fea's Petrel and very rare, until recently presumed extinct.  Tahiti Petrel is a common species that ranges as close as Panama.  Interestingly we saw the Tahiti Petrel not long after a tropical cyclone had left the Gulf of Mexico.  We've seen some great vagrants over the years but I think the Tahiti Petrel is the least expected of them all and, as such, our biggest MEGA to date.  I think it's also our 20th species of tubenose for the boat!  That's 20 species by AOU/ABA taxonomy, so it doesn't include Scopoli's Shearwater!

We did not find as many marine mammals this spring as some years but we did see Bottlenose Dolphins out in the deep on several trips and there were good numbers of Pilot Whales in early June.  A pod of Cuvier's Beaked Whales popped up beside the boat on May 19, but in contrast to most years, we never found any Gervais' Beaked Whales this spring.  Other charismatic megafauna included Loggerhead and Leatherback Turtles, Blue Marlin, and a couple of leaping devil rays.  We rummaged through the Sargassum on several trips and looked at what Audubon's Shearwaters and other seabirds feed on there.

As usual we had a good crew aboard and would like to thank everyone who made it possible to carry out this epic run of trips.  Our spotters / leaders this spring included: Steve NG Howell, Nate Dias, Chris Sloan, Seabird McKeon, Jeff Lemons, Peter Flood, Ed Corey, Sage Church, Andrew Dreelin, and Liam Waters.
-Brian Patteson

Our spring trip lists are compiled here, and I have put together some additional photos from the spring below!  Thank you to everyone who worked hard and contributed photos for the blog over the eighteen days stretch - it was much appreciated so that I could get everything posted each evening in a timely fashion and still get a little sleep!  Thank you also to our Spring Gallery contributors...there may be more if I receive some additional images!  -Kate Sutherland

First of all, here is another photo of the Tahiti Petrel by Peter Flood followed by a couple of photos taken as Brian was examining images on the backs of cameras and discussing the size of the bill (by Kate Sutherland)
Maili Waters (MA) was one of our participants for three trips near the end of the Blitz and she captured some nice images of the Stormy Petrel II and her seabirders!  I love these!  And an image of one new species for me, the Devil Rays that came right in under the pulpit!
Nate Dias (SC) was back helping us as a leader after a few years hiatus and he captured these images over the five trips he was on this spring!
The young Black-capped Petrel from June 8:
Great Shearwater with what looked to be some food in its mouth!
 Scopoli's Shearwater
Band-rumped Storm-Petrel (Grant's type)
 Wilson's Storm-Petrel
Some nice images of the Pilot Whales we saw on June 7th
& a nice shot of one of the many Sargassum Midgets we saw this spring!
Peter Flood (MA) sent me a few more images for the gallery!  He and Steve Howell contributed most of the photos this spring...
 A nice white faced Black-capped Petrel
We had some incredibly close passes this spring by Leach's Storm-Petrels!  Their bill is much larger than a Band-rumped Storm-Petrel and they have a much grayer head, as you can see here.
South Polar Skua from early in the Blitz
A gorgeous image of one of the dark Pomarine Jaegers we saw this spring
I also captured a few images...well a lot actually!  But here are a few more for the gallery from me, Kate Sutherland.
A few Black-cappeds
 The juvie Black-capped with a Great Shearwater
Audubon's were around in good numbers this spring and we had some nice photo ops!
Great Shearwater tossing back a piece of chum
 Scopoli's and Great Shearwaters behind the boat
Our "smudgy-rumped" Leach's from May 28
A Band-rumped posture we don't always get to see! (Grant's type)
A couple images of one of the Arctic Terns we saw this the rain!
One of the Long-tailed Jaegers that came in well to the boat
& we did have at least one Portuguese Man-of-War this spring!
I have so many more...but will leave it at that for this year!  If I get my Flickr album together soon I will put a link here!  Thanks again everyone for coming offshore with us!  -Kate

Sunday, June 10, 2018

Saturday June 9, 2018 - by Kate Sutherland

Our final day of the Spring Blitz brought some lighter winds from the south and our commute offshore to the deeper waters beyond the shelf break was quite nice with a few shearwaters along the way.  There was some rain where we slowed down and began chumming and while uncomfortable for humans, and frustrating for keeping optics dry, it was perfectly suitable for seabirds!  As we stopped on our first drift just after 8:00, we added all of the birds we typically see in the Gulf Stream to our list - and with nice views too!  There were at least five Black-capped Petrels that came right in to the chum plus Scopoli's (the Mediterranean breeding Cory's type), Great, and Audubon's Shearwaters. (photo of a Great Shearwater by Nate Dias)
Wilson's Storm-Petrels began feeding on our chum and a few Leach's Storm-Petrels joined making some nice passes in the rain.  Band-rumped Storm-Petrels were around as well, but were not quite as cooperative as yesterday - yet!  As we tacked offshore, then back inshore later in the morning and into the afternoon we pulled a very nice feeding group with us.  The shearwaters were feeding behind us giving some incredible views of the large, brute-like Atlantic Cory's with the more diminutive Scopoli's together - a nice study!  Plus the Great Shearwaters were vocalizing as they fought over bits of fish;  Audubon's zipping in and out of the slick (photo by Nate Dias),
occasionally coming right up to the back of the boat before flying off to settle back in the sargassum, the floating brown algae of the Gulf Stream, that is their preferred habitat.  The finale was a good one with our flock back inshore nearing the shelf break, we had both Leach's Storm-Petrel and a summer breeding Band-rumped Storm-Petrel (presumed Madeiran type) in the slick at the same time! (Band-rumped photo by Kate Sutherland)
As everyone was having their best looks of the day at Band-rumpeds, a Manx Shearwater flew by and landed ahead with some Great Shearwaters!  We were able to approach and have some excellent views of this bird flying into our slick, and sitting on the water - once seen, it was obvious how different they are from Audubon's - yet this is the species most easily confused with them.  As we watched the Manx with both Great and Audubon's Shearwaters, the non-molting Band-rumped made some nice passes again as well!  What a way to end the Blitz!

Thank you to everyone who joined us out there today - and thanks to Eagle Eye Tours for organizing a group that was with us for the last two days of the Blitz.  Thanks to Steve Howell and Nate Dias for helping us on this last day, and thanks to them also for contributing photos for the post!  Next trips - July!  Check our website for the schedule...

Species List June 9, 2018
Black-capped Petrel  23
Cory's Shearwater  27 / Scopoli's Shearwater  4-5
Great Shearwater  25-26
Manx Shearwater  1
Audubon's Shearwater  51
Wilson's Storm-Petrel  112-127
Leach's Storm-Petrel  7-9
Band-rumped Storm Petrel  5-7
Pomarine Jaeger  1
jaeger sp.  1
Offshore Bottlenose Dolphins  11

Steve NG Howell's final photo narrative for spring 2018:
The day started in heavy rain, when several Audubon’s Shearwaters showed well in the gray skies
Black-capped Petrels showed as soon as we put out some chum, here a black-faced type
And here a white-faced Black-capped Petrel
Most Band-rumped Storm-Petrels were winter-breeding Grant’s types, like this individual in wing molt…
But one fresh-plumaged summer breeder (presumed Madeiran Storm-Petrel)  appeared in early afternoon near the shelf break
Wilson’s Storm-Petrels featured fresh juveniles, like this
But most were molting adults
The Leach’s Storm-Petrels were abraded first-summer and, like this bird, presumed second-summer individuals
While underwing pattern is often cited as a feature for Scopoli’s Shearwater, but lighter structure and slender bill is often easier to see…
As compared to this “huge-billed” Cory’s
Audubon’s Shearwaters showed well, which helped in the afternoon…
When this heavy-bodied Manx Shearwater appeared.

Friday, June 8, 2018

Friday June 8, 2018 - by Steve NG Howell

A wind direction switch again, this time to light southeasterly, as we left the dock under mostly cloudy skies with a red sun rising over Hatteras Village. A Black Tern and a few shearwaters punctuated today’s commute out to the Gulf Stream where we spent the day cruising slowly along in search of oceanic desert birds. The chum slick slowly started to pull in Wilson’s Storm-Petrels but it took a while before the first Black-capped Petrel appeared, and even longer for the first Band-rumped Storm-Petrel. But then Band-rumps started to show well and we slowed to drift, with good light plus current and wind directions conspiring to make a slick to remember. Over the course of 30 minutes we were treated to an absolutely amazing show of point-blank Black-capped Petrels, shearwaters, and storm-petrels all around the boat in dazzling light. Particularly nice was a recently fledged juvenile white-faced Black-capped Petrel that fed on chum next to the boat.
As has happened in recent days, the “Cory’s Shearwaters” that came close and into the slick were again of the Mediterranean-breeding population known as Scopoli’s Shearwater (split in the rest of the world but not [yet] by North American authorities). Most of the Band-rumps were molting birds from the winter-breeding population known as Grant’s Storm-Petrel (don’t even think about asking if that’s been split yet in North America...).
We also saw a few Leach’s Storm-Petrels, which were “just” Leach’s given that we were in the Atlantic, far from the two recently split populations of Leach’s from Mexico. As in all birding, location is a huge clue when looking at seabirds. Shortly before lunch, John Fitzpatrick with the Cornell Lab contingent spotted a distant gadfly that proved to be a (presumed) Fea’s Petrel, but it stayed far away and, although highly unlikely, it could have been a Zino’s Petrel given the views (moreover, Fea’s is split into two species by many authorities, adding to the challenges of pelagic birding!). As well as birds and flyingfish we saw some nice mammals, starting with bow-riding Bottlenose Dolphins in the morning, and then a dispersed group of logging Pilot Whales that seemed curious around the boat and gave amazing views, even spy-hopping like this animal.

As we headed on slowly back towards the alternate reality of mainland life we came upon a spectacular current break between the blue offshore and green inshore waters, after which birds dropped off noticeably and it was time to pick up speed and head back to port, slowing to see a couple of distant jaegers that kept heading north and avoided positive identification. All in all, another amazing day offshore.

*Thank you to everyone who joined us out there today!  A big thanks to Brian Sullivan for organizing a group from the Cornell Lab of Ornithology and for taking care of the eBird lists for yesterday and today.  Thank you also to our leaders: Steve NG Howell, Nate Dias, and Liam Waters, they all did a great job getting everyone on the birds!  Thanks to Steve for all of his hard work on the blog and photos for me as we approach Day 18... -Kate

Species List for June 8, 2018
(presumed) Fea's Petrel  1
Black-capped Petrel  23
Cory's Shearwater  16 / Scopoli's Shearwater  3
Great Shearwater  10
Audubon's Shearwater  23
Wilson's Storm Petrel  68-78
Leach's Storm-Petrel  3-4
Band-rumped Storm-Petrel  8-10
Black Tern  1
Parasitic / Long Tailed Jaeger  2
Pilot Whale (presumed Short-finned)  30-35
Offshore Bottlenose Dolphin  5

Another image of the young Black-capped Petrel that put on such a nice show by Brian Sullivan.
And one more by Nate Dias - this bird was very curious about the boat and also came in to feed on the chum.

Another Black-capped Petrel
Juvenile Black-capped Petrel and Great Shearwater
Presumed Scopoli’s Shearwater
Another molting Grant’s [Band-rumped] Storm-Petrel
And a worn-plumaged presumed second-summer Leach’s Storm-Petrel for comparison
The Band-rumped Stormies were super excited about the chum today!  Photos by Nate Dias
An Oddspot Midget from the morning commute offshore.