Monday, December 2, 2019

Black-capped Petrels to the North - by Kate Sutherland

This past August I was hired as the seabird observer for a NOAA beaked whale cruise.  The platform was the R/V Hugh R. Sharp owned and operated by the University of Delaware and the project was Atlantic Marine Assessment Program for Protected Species: Integrated Technologies for Deep Diver Ecology Project (ITS.DEEP 2019) headed by Chief Scientist Dr. Danielle Cholewiak of the NOAA Northeast Fisheries Science Center in Woods Hole, MA.  This meant that in addition to surveying for seabirds in a new location far north of my usual haunts, I would also get to see some really cool species of beaked whale and other cetaceans more commonly encountered far from shore.  And while beaked whales are the specialty of others aboard the ship, seabirds happen to be mine.  As it turns out, we headed offshore into another one of my specialties, the Gulf Stream!

I was not sure what to expect offshore from Massachusetts, but had some idea what had been seen on previous cruises up there and also had been on at least two pelagic trips that covered some of the canyons offshore.  We also had recently helped American Bird Conservancy and partners capture and fit ten Black-capped Petrels with satellite transmitters that we had been watching more or less live for months.  A number of the white faced birds had ridden the wind right up to the shelf break south of George's Bank.  One was even documented in one of the areas that we transited earlier in the month!
Many of the dark faced birds were foraging to the east of Cape Hatteras, way offshore.  In 2008 Steve Howell and Brian Patteson wrote about the possibility that these two types of Black-capped Petrel use different areas to forage, breed on a slightly different schedule, and also perhaps have different nesting locations.  We have learned a lot more about how to differentiate these two types at sea and also more about the nesting locations of the dark faced birds.  Until October of this year, we had no idea that a white faced bird might be nesting on Hispaniola, but one of the tagged individuals was recorded over and around the island.
The timing is earlier than that of the dark faced birds, so this one individual does support that part of the narrative.  It did not, however, lead us to a new and unknown nesting location.  But this is just one bird, we don't even know for certain that it is a breeding individual, but we do know that petrels in the genus Pterodroma exhibit philopatry, or the tendency to return to the island or locale from which they fledge.

Back to Massachusetts.  Black-capped Petrels have certainly been seen offshore up there, but rarely more than one or two.  Photographs of individuals have all been the white faced type.  There have also been Black-capped Petrels recorded in the Western Palearctic, majority white faced but dark faced and intermediate birds have been recorded as well.  On this NOAA survey in August, over a ten day period near and offshore of the Continental Shelf, Skye Haas and I recorded exactly 50 Black-capped Petrels.  A number of these were easily identified as white faced birds (photo by Kate Sutherland),
but there were also some that looked more intermediate, and I did photograph at least two dark faced birds.  This is interesting for a number of reasons.  Number one, that's a lot of Black-capped Petrels!  How could there be so many up there, yet trips in some of the same areas using chum do not encounter similar numbers?  Perhaps it had more to do with the conditions that were in the area we transited.  The water on and offshore of the shelf break was up to 28 degrees C and moving around three or four knots.  It also looked like Gulf Stream water, gorgeous blue, full of Band-rumped Storm-Petrels, Audubon's Shearwaters, and of course Sargassum.  So is it possible that these birds are using the areas where the Gulf Stream moves offshore to the northeast and we were just lucky that those waters happened to be where we were?  Or are they always up there, feeding in the canyons and around the seamounts, and it just happens that they are too far to be attracted to the birding trips that are only out for a night or two farther to the west than we were on the research vessel?  Who knows, but it is certainly worth noting that they were there!  Also makes me wish that someone was out there surveying more often, but right now, we'll take the transmitters and the occasional trips out to that area!

Our trip from Hatteras October 18th turned up nice numbers of Black-capped Petrels, various types, but many intermediate birds, only maybe one or two white faced birds, and a handful of nice, dark faced birds.  I know I write this again and again, but Black-capped Petrels are incredible birds, oceanic superheroes, that are likely facing many threats not only where they nest, but also at sea.  Stay tuned for the next chapters in the saga.  And check out some of the sites below that have information about what is being done to protect these birds at sea and on Hispaniola.  I hope to be out there again next year to see what Black-capped Petrels look like offshore of Massachusetts in the summer of 2020!

Birds Caribbean has a working group specific to Black-capped Petrels:

American Bird Conservancy spearheaded the transmitter project:

Along with Atlantic Seabirds:
They are also partnered with USGS South Carolina Cooperative Research Unit & Clemson University

Groupo Jaragua is based in the Dominican Republic:

A few more images of Black-capped Petrels from the R/V Hugh R. Sharp.  First two birds in one frame on August 24, 2019, which was notable!  We saw multiple Black-capped Petrels together on a few occasions.  Then two record shots of one of the dark faced individuals we saw, this one from August 21, 2019.  Photos by Kate Sutherland.

Thursday, October 24, 2019

October 18, 2019 - Diablotin - by Kate Sutherland

Our last offshore excursions were in late August, the September trips were cancelled due to Hurricane Dorian and uncertainty about when Hatteras village would be open to visitors.  So we were looking forward to getting offshore last week for our annual October outing! 
Winds were strong from the west for a day or two preceding our scheduled trip, but due to shift around more to the north west and fall out a little on Friday.  Satellite images showed a nice temperature break to the south of us, so that is what we set our sights on that morning!  On our way out to the shelf break we found a nice flock of Cory's Shearwaters, with at least one Scopoli's and one Great, feeding over a school of false albacore.

October is a nice month to get offshore here because you just never know what you might turn up in the blue water.  But one species we do know that we should find is Black-capped Petrel.  And in October they are fresh plumaged and striking, not to mention excellent for photographing (Kate Sutherland). 
Just over the shelf break the water started warming up, but it was not the clear, deep blue of the Gulf Stream quite yet.  Regardless, Black-capped Petrels caught the scent of our chum and came to us directly.  In less than thirty minutes we had nineteen around us, then twenty-five, our maximum count was twenty-eight!  Great Shearwaters also responded well to the chum and stayed with us for most of our time out in the deep (Kate Sutherland). 
Audubon's Shearwaters were out there, but difficult to see as they flew close to the water in fairly steep waves.  A couple came to feed in the slick, so at least everyone had a chance to see the species well!  Wilson's Storm-Petrels were out there too, but just a handful were seen over the course of the day.  Just before we began heading back toward the shelf break a Pomarine Jaeger came in to investigate our following flock, but it did not chase or harass our shearwaters as we sometimes see.  Instead, it was happy to settle in and feed alongside of them, an interesting combination! (Peter Flood)
The Black-capped Petrels were, however, unimpressed with the seemingly kind jaeger and dogged it a few times before sailing away.

As many of you know, there are two types of Black-capped Petrels that we encounter offshore here, white-faced and dark-faced birds.  There are also many that fall into an intermediate category.  Molt timing and genetic analysis in these two types of Black-cappeds indicates two different nesting populations.  Nesting birds on Hispanola that have been documented and/or tagged have all been dark-faced or intermediate birds.  This spring an ongoing project by ABC (American Bird Conservancy) to capture these petrels at sea came to Hatteras with a new method for capture and tags for up to ten birds.  Their focus was to capture and tag the white-faced birds so they would perhaps lead us to an unknown nesting location.  We were lucky enough to partner with ABC, South Carolina Cooperative Fish and Wildlife Research Unit, and Birds Caribbean - Black-capped Petrel Working Group for this expedition.  Chris Gaskin of the Northern New Zealand Seabird Trust brought his one of a kind net gun that was key to the success of this expedition!  The ABC press release is here: May 2019 marked the first time that Black-capped Petrels have ever been captured at sea!  A website tracked the individuals with GPS tags over the summer and now, two birds are still transmitting, one white-faced and the other dark-faced.  The white-faced bird headed to Hispanola at the end of September and has been there since over land and at sea, while the dark-faced bird was still at sea to the east of Cape Hatteras.  A link to the map is here:  It looks like the white-faced bird could possibly be on a pre-laying exodus to the north of Hispanola right now after spending some time near one of the known breeding locations.

White-faced Black-capped Petrels have never been documented nesting on Hispanola (until possibly now), but that doesn't mean they are not there.  So perhaps there are just two populations with staggered nesting times on Hispanola, perhaps both types of Black-cappeds nest in the same fashion elsewhere in the Caribbean.  Dominica has sufficient petrel activity for us to believe that they are nesting there, perhaps only white-faced birds are there, perhaps both - no one yet knows because a nest has not been found there to date.  So our observations on this past trip are interesting, especially when we can look at the types we found out there this month.  The majority of the birds seen and photographed were dark-faced (Peter Flood)
or intermediate types, though there were at least three white-faced birds photographed.  For what it's worth we see more white-faced birds in the spring here, this could be because by fall most have moved closer to the nesting grounds in the Caribbean.  There is still a lot to discover about our signature species, the Black-capped Petrel, locally known as Diablotin on Hispanola.  And while we are very lucky to see them on just about every trip offshore from Hatteras, their true population size is unknown, likely in the low thousands.  We also know little about threats they face at sea because their movements in the deep waters of the Atlantic are mostly unknown but for at sea observations, and a small number of GPS tracks.  Pulling all of this together, the luxury of spending a day in the company of fifty of these enigmatic gadflies becomes quite clear!

Thanks to everyone who joined us offshore for this October trip and to Kyle Kittelberger for helping us as a leader!  Thank you also to Peter Flood for contributing photos for this post.

Species List
Black-capped Petrel - 49 to 57
Cory's Shearwater - 52
Scopoli's Shearwater - 1
Cory's type - 20
Great Shearwater - 27
Audubon's Shearwater - 12
Wilson's Storm-Petrel - 4 to 5
Pomarine Jaeger - 1
Pom / Parasitic - 1

Common Loon - 1
Herring Gull - 6
Laughing Gull - 18
Sandwich Tern - 7 to 8
Dunlin - 1
sandpiper sp - 1
Mourning Dove - 1
Cedar Waxwing - 1
Common Grackle - 1
Brown-headed Cowbird - 1

Bottlenose Dolphin - 5
Ocean Sunfish (Mola mola) - 1
Portuguese Man of War - 4

A dark-faced bird (Kate Sutherland)
And one that is more intermediate (Peter Flood)
Great Shearwaters were with us all day in the slick giving some nice comparisons with Black-capped Petrel.  Superficially they seem to have similar markings, but when seen in life they look quite different from one another! (Kate Sutherland)
Our very cooperative Pomarine Jaeger in flight (Peter Flood)
flying with one of the Great Shearwaters (Peter Flood)
& on the water with a Great Shearwater (Kate Sutherland)
One of the offshore Bottlenose Dolphins (Kate Sutherland)
And finally, a chub mackerel that was on the surface near the boat! (Kate Sutherland)

Tuesday, August 13, 2019

August 9 & 10, 2019 - by Kate Sutherland

The Gulf Stream current was pushed offshore Friday morning, so we headed out to the south thinking we might find some and ended up being able to just cruise around all day without worrying about being swept up to the north.  In turn this meant that the water we found out there was more blue green than the nice, blue Gulf Stream water, and the birds were scattered around.  Saturday we found a better condition out there with Sargassum scattered out to the deep and its associated life.  Our birds of note for the weekend were both dark with light bellies and neither stuck around for a leisurely study!  Friday morning on our way out to the shelf break, an adult Brown Booby flew right up the port side of the boat, crossed ahead, and flew directly away from us off the starboard bow!  Quick, but seen well and I was able to get at least a record shot!
On Saturday morning as we were heading toward a distant flock of tropical terns a group of Black-capped Petrels flushed from the water on our starboard side, a handful of the birds flew ahead of the boat into the sun glare.  As they passed the bow, Brian saw what looked to be a light morph Trindade Petrel in the group.  We gave chase and the flock of Black-cappeds zig-zagged all over around us, flying in and out of the glare at the same time we were trying to get participants on the smaller gadfly among them.  Not quite the way we like to have it play out, but an excellent sighting all the same!

Black-capped Petrels were scarce on Friday, but they were around on Saturday and even responded much better to the chum!  Shearwaters were a bit scarce both days, but on Friday we found a nice group of feeding Cory's, Great, and Audubon's shearwaters under a very dynamic flock of Sooty Terns.  All three species were a bit more cooperative with the chum and for photos on Saturday, but could not turn up a nice, classic Scopoli's for the weekend.  There were a number of Cory's type shearwaters that looked like good candidates, but none with well marked underprimaries.  We did see some nice Atlantic Cory's (borealis)! (photo Kate Sutherland)
Our storm-petrels were a bit scarce and while we expect the numbers of Wilson's to be winding down as the summer progresses, it should still be a nice time to find some Band-rumped Storm-Petrels out there, but perhaps they were out in that hotter water this weekend!  We did see them on both trips and a few came in quite well!  Red-necked Phalaropes just began showing up this past week according to Brian, and while we saw them on both days, we had a flock that allowed close approach on Saturday.  (photo Kate Sutherland)
The tropical terns also did not disappoint!  Bridled Terns flew right by the boat on Friday morning and Sooty Terns came in well or were approachable on each trip.  Friday we had the feeding flock of shearwaters with over 20 Sooty Terns feeding with them, when we first approached this group there were also a handful of Bridled Terns there as well!  Saturday we found one Sooty Tern feeding on small fishes in the Sargassum, the show it put on for us was spectacular!  Swooping down to the water again and again, then flying right past us, seemingly curious about what we were doing edging in on its meal. (photo Kate Sutherland)

Westerly winds brought some other interesting creatures offshore and we saw dragonflies and moths out there both days, with one Monarch flying by offshore on Saturday! (photo Kate Sutherland)
Atlantic Spotted Dolphins visited us to ride under the bow both afternoons on our way back to the dock, and a shark checked out our chum slick on Saturday afternoon in the deep!  Looking over the photos of the dorsal and caudal fins, the most likely candidate is a shortfin mako, but I will send it off to someone who knows more about sharks than I do for a final identification.

Thanks to everyone who joined us out there, we had a really nice mix of new and returning participants on each trip.  Another huge thank you goes to Kyle Kittelberger and Ed Corey for helping us to lead the trips, and to James Coleburn for helping me on the deck on Friday.

Species list for Aug 9 / 10
Trindade Petrel  0 / 1
Black-capped Petrel  12 / 43 to 45
Cory's Shearwater  64 to 69 / 35 to 36
Great Shearwater  10 / 4
Audubon's Shearwater  30 / 11
Wilson's Storm-Petrel  29 / 48
Band-rumped Storm-Petrel  10 / 1
Brown Booby  1 / 0
Red-necked Phalarope  15 / 14
Laughing Gull  0 / 1
Sooty Tern  28 / 9
Bridled Tern  6 / 0
Sooty/Bridled Tern  10 / 3
Least Tern  0 / 1
Black Tern  4 / 4
Least Sandpiper  1 / 1

Atlantic Spotted Dolphin  12 / 8

shark sp. - possible shortfin mako - 1

Audubon's Shearwaters were very cooperative on Saturday! (Kate Sutherland)
Great Shearwaters gave some nice views on both trips! (Kyle Kittelberger)
Wilson's Storm-Petrels on the water (Kate Sutherland)
This Sooty Tern was most obliging on Saturday!  (top photo Kate Sutherland, bottom Kyle Kittelberger)
This young Laughing Gull came in to the slick when we were offshore.  (Kate Sutherland)
& a photo of the shark, the pale and smoothly rounded (not pointed) dorsal fin plus lunate caudal fin both point toward shortfin mako (Kate Sutherland)
Of course we found some Oddspot Midgets out there too! (Kate Sutherland)

Monday, July 29, 2019

July 26 & 27, 2019 - Summer Northeasterlies - by Kate Sutherland

Brian has said many times, northeasterly winds during July and August can bring incredible diversity here offshore of Hatteras.  The weather leading up to this pair of trips at the end of July had us progressively more excited as Friday approached.  The wind shifted to the north Wednesday, and it blew all day Thursday - really blew - so hard that we were a little worried there might be too much wind to make Friday happen.  But checking the Diamond Shoals Buoy at 0400 that morning, we were relieved to see that the peak wind speeds had fallen enough for us to say "oh yeah, we can make it!"  Game on!  And what a couple of days they were!  Epic.  Fifteen pelagic species over two days.  End of July.

Friday was a stormy-petrel kind of a day.  Band-rumped Storm-Petrels were super cooperative in the chum and we had a steady stream all day, both the Grant's type and some of the "little band-rumps."  Just after 0900 leader Ned Brinkley spotted a White-faced Storm-Petrel in the slick! (photo Kate Sutherland)
Usually these birds are fleeting visitors for us down here, but this bird was hungry so we stopped and put out more food, which enticed it to stay around for over 20 minutes!  Later in the morning, when we were out in deeper, warmer water, we were just picking up from a drift with the chum when Brian spotted a Fea's Petrel coming in hot on the starboard side!  It flew down the side of the boat, bow to stern, closest bird, then shot away behind a few parting arcs before moving out of view!  Some days this is how it happens, other days these birds will come back to some fresh chum and spend more time...but for those participants who were in the right place at the right time, the view was stellar!  Shearwaters were not out in huge numbers, but we saw the expected species - Cory's, Scopoli's, Great, and Audubon's - and our Black-capped Petrels put on quite a show all day!  (photo by Brian Patteson) 

Saturday the wind was not blowing quite as hard, so the run offshore was a bit smoother than Friday's.  Near the shelf break we found water that was blended and greenish, there were few birds to be seen.  Finally we reached an area with some activity and our slick began to attract a few birds, soon they were popping up all around us in the breeze!  Sooty Terns were around and we had a number come in to visit the boat, making incredibly close passes! (photo Kate Sutherland)
Shearwaters came in nicely to the slick and we had Cory's, Scopoli's, Great, and Audubon's all feeding behind us with the Wilson's!  At times, even the Black-cappeds were feeding with them!  (photo Kate Sutherland)
Thanks to the calmer conditions we were able to make it out farther than Friday, and we found a nice current edge lined with Sargassum out in the deeper water.  Out past this, Brian spotted a dark tern up ahead, there were some Sooty Terns around, but this one looked more noddy-like.  We did our best to get everyone on it and snapped a few photos, it was indeed a noddy!  It seemed to be heading back toward the edge we had previously crossed, so we headed back that way.  Just after noontime the bird of the day flew in, the shout came from the wheelhouse "Get on this petrel!!  Right here!  10 o'clock!  Right behind the Cory''s a BERMUDA PETREL!!"  Organized chaos followed as the bird came in to check out our slick, flying by close, then away, then back for a couple more passes.  WOW! (photos by Brian Patteson)
Incredible views, best since our May 25, 2015 bird!  The fresh plumage at this time of year indicates an individual that just fledged a month or two ago.  Not even a few minutes later, Brian again shouted, this time it was "White-faced Storm-Petrel!!"  Sure enough, another one of these incredibly dynamic stormies came hopping across the slick.  We had quality time with this one as well, then it revisited the boat over an hour later! (photo by Kate Sutherland)

Leach's Storm-Petrels were seen on each trip, though the birds on Saturday were a bit more cooperative.  A young Long-tailed Jaeger came in on Saturday as well to harass our storm-petrels in the slick.  It was in turn harassed by a Black-capped Petrel!  A Red-necked Phalarope made a quick fly-by on Saturday as well.  It was an incredible set of trips - truly epic.

Thank you to Ned Brinkley for helping Brian & I lead these trips, and thanks to everyone who joined us for this set!  Those who came for both trips really had an amazing experience and were rewarded for sticking with it for two bumpy days out there!  The days that are tough for humans are almost always excellent for seabirds, we proved that again!  Our next trips are August 9, 10, 16, 17, 23, 24, 25 - join us!

Species List for July 26 / 27
Fea's Petrel  1 / 0
Bermuda Petrel  0 / 1
Black-capped Petrel  44 / 94
Cory's (type) Shearwater  20 / 30
Scopoli's Shearwater  2 / 2
Great Shearwater  9-11 / 20 -22
Audubon's Shearwater  2 / 8
Wilson's Storm-Petrel  90-105 / 100-110
White-faced Storm-Petrel  1 / 1
Leach's Storm-Petrel  1 / 4
Band-rumped Storm-Petrel  28-32 / 9-10
Red-necked Phalarope  0 / 1
Brown Noddy  0 / 1
Sooty Tern  0 / 17
Long-tailed Jaeger  0 / 1

A few more Cahow photos, what a bird!  (Kate Sutherland)
Black-capped Petrels really put on a show for us in the slick both days! (Brian Patteson)
They were feeding on the chum with the Great Shearwaters, allowing a nice study of these two species together!  (Kate Sutherland)
Any day you get to see a Black-capped Petrel is a good day!  The tags deployed at the beginning of the spring are still tracking birds - check the map out here:  (Kate Sutherland)
On Friday the shearwaters kept their distance, but Saturday we were able to get some better views of the Scopoli's (Kate Sutherland)
and we had Great Shearwaters right next to the boat plucking pieces of fish from our chum cage! (Brian Patteson)
They were scurrying along the surface to snatch pieces and looked like they were just walking around out there! (Kate Sutherland)
Audubon's were scarce on Friday, but we didn't find any Sargassum to speak of, so having them follow us on Saturday was quite a treat!  Most that we saw were young birds like this one.  (Kate Sutherland)
Wilson's Storm-Petrels came super close to the boat both days!  (Kate Sutherland)
& the White-faced Stormies!!  Top two images are Friday's bird (one with a Band-rumped), the following are from Saturday (one with a Wilson's)! (Kate Sutherland)
As I mentioned in the trip report, the Band-rumped Storm-Petrels on Friday were just incredible!  Though we had really nice passes on both trips!  (Brian Patteson - top, Kate Sutherland - bottom)
It was really cool to see the Band-rumpeds flying with the White-faced Storm-Petrel on Friday!  (Kate Sutherland)
Record shot of the Brown Noddy (Kate Sutherland)
Sooty Terns passing by the boat, all of the individuals we saw were adults.  (Kate Sutherland)
And a photo of the Long-tailed Jaeger (immature).  (Kate Sutherland)