The prelude to the Spring Blitz happened this weekend with a trio on May 16, 17, and 18th. Weather has been pretty uniform recently with winds from the southwest and Friday was no different. Saturday we had a little pulse of south southwest wind midday offshore, but Sunday was mostly a breezy west wind with a bit of west northwest out there midday. Species counts mirrored these conditions with eight species we consider "pelagic" on Friday, six on Saturday, then four on Sunday. In spite of the low diversity we had close to 300 (297!!) Black-capped Petrels tallied over the three days - this is likely low because I am pretty conservative in my count methodology. Not only did we see a lot of Black-capped Petrels - they were close! We saw their bicolored feet every day as they swooped down to the slick to see what we'd offered!! It's nice to have a set like this so we can remind those who join us out there just how incredible it is to see these endangered gadfly petrels, locally known as the Diablotin ("little devil") where they nest on Hispaniola. While you can see them from other ports on the east coast, we are the closest to the deep water here and also right in the core of their range. Only about 100 burrows are known for Black-cappeds on Hispaniola - they occur both in Haiti and Dominican Republic nesting high in the mountains where monitoring them is a challenge. Haiti is a challenging country to be a human much less a seabird...and Dominican Republic is seeing an uptick in development for tourism and wind farms, both occurring near known colonies and posing a number of risks to the birds. These are in addition to the threats that introduced predators like mongooses, rats, dogs, cats, and pigs pose to these burrow nesting seabirds. Due to all of these challenges it is impossible to estimate exactly how many there are but in a 2023 report 2,000 to 4,000 was listed with about 500 to 1,000 of these being breeding individuals.
Our long-time friend, Seabird McKeon, who is now the director of the Marine Program at American Bird Conservancy (ABC) joined us for this set of trips to see how they were for seeing Black-cappeds, a species that ABC has invested a lot of time and money in over the past many years. They spearheaded the tagging project that we, and other organizations, assisted with in 2019 (you can read more about that here: Expedition Diablotin ) and we are hopeful another project like this will happen in the future. In the meantime they are looking for places offshore from the main island that could be suitable to host a colony of Black-cappeds. They (with partners at Sociedad Ornitologica de la Hispaniola (SOH), Critical Ecosystem Partnership Fund (CEPF), The Ministry of Environment and Natural Resources (Ministerio de Medio Ambiente y Recursos Naturales - SEMARENA) have found one, but it has invasive species on it - so the first step will be pest eradication - not a small task! So we wanted to let people know a bit more about this project and how they might be able to help...you can find a link with information to donate here: Isla Alto Velo and we will be highlighting this on our trips this year and next. So be prepared to hear about this incredible seabird when you join us on the Stormy Petrel II for a trip to the Gulf Stream!
Another question many have when they join us offshore is about the forms of Black-capped Petrel. Are there two species? Six? What about subspecies? What is going on with these birds? Well, the honest answer is we don't know! Years ago there was a study done looking at mitochondrial DNA in our NC Museum of Natural Sciences, what they found was two distinct nesting populations. These specimens are from the 1970s to the early 1990s so some time has also passed since these birds were collected. There was not enough evidence to say they are even subspecies. Our suspicion is that historically these birds may have been distinct species, but as they were extirpated from one location after another by human predation and disturbance in the Caribbean, the places they had to nest became more and more limited. Their population also decreased - as we have observed with many different species that overlap with human settlement like the Bermuda Petrel, Zino's Petrel, and Jamaican Petrel. We also know from studies done on Round Island that Pterodroma petrels readily hybridize - the birds there could easily just be called a hybrid swarm! It is likely that Black-capped Petrels could be currently undergoing change, well, really everything is always changing, evolving. I keep track of our "White-faced" and "Dark-faced" (per eBird) individuals that we see on our trips. We prefer to just call them light and dark forms. The reality is that very few individuals we see fall into the really light form category or really dark form category - most are some intergrade of the two. I wanted to let those who join us know what I consider to be "light" or "dark" and many will not agree, but I really am not too concerned about that since until we have been able to do the genetic work for the lineage of these birds, we really won't know anything!
Following are some images of birds from our trips this past weekend that I would call light form individuals. These birds have a very small, distinct black cap above the eye with just a little dark below. The nape is white. They have a narrow or absent "chest spur." The underwing has a very narrow black margin. Pretty simple. We definitely see fewer of these and they are often found much farther along in the Gulf Stream - offshore from New England and on the other side of the Atlantic.
a solid, dark "chest spur" that can be very broad and sometimes almost wrap around their chest. Their underwings have bold black markings and sometimes they have dark feathering in their "armpits" or along the sides of their bodies. They can also look quite petite at times giving the impression of something as small as a Bermuda Petrel. Also pretty straightforward. We see many more of these than the light form birds. Their range is thought to be offshore of the southeastern US coast.
The first image is one individual, then two photos (dorsal / ventral) of two other individuals.
Leaders on our trips in addition to me were: Brian Patteson, Daniel Irons, and Jeff Lemons - thanks, gentlemen!!!
All photos today are mine so © Kate Sutherland
eBird Trip Reports can be found here:
Species List for 16 / 17 / 18 May 2025
Red-necked Phalarope 0 / 20 / 0
Parasitic Jaeger 1 / 0 / 0
Pomarine Jaeger 1 / 0 / 0
Common / Arctic Tern 0 / 3 / 0
Common Loon 1 / 1 / 0
Wilson's Storm-Petrel 71 / 80 to 90 / 27
Band-rumped Storm-Petrel 4 to 5 / 1 to 2 / 0
Leach's / Band-rumped 2 / 0 / 0
Black-capped Petrel 126 / 92 to 93 / 79
Atlantic Cory's Shearwater 7 / 4 / 4
Cory's / Scopoli's 5 / 9 / 2
Sooty Shearwater 2 / 0 / 0
Sargasso Shearwater 17 / 17 / 15
Black-bellied Plover 0 / 0 / 1
Ruddy Turnstone 1 / 0 / 0
Red Knot 2 / 0 / 0
Sanderling 0 / 7 / 0
Semipalmated Sandpiper 0 / 0 / 7
peep sp 0 / 0 / 16
shorebird sp 6 / 0 / 2
Laughing Gull 0 / 1 / 2
Least Tern 2 / 0 / 0
Royal Tern 0 / 0 / 4
Barn Swallow 2 / 2 / 0
Offshore Bottlenose Dolphin 10 to 12 / 17 / 10 to 12
Atlantic Spotted Dolphin 7 / 0 / 0
Scalloped / Carolina Hammerhead 0 / 2 / 0
shark sp 0 / 0 / 1
Whalesucker 0 / 0 / 1
Monarch Butterfly 0 / 1 / 0
Dragonfly - skimmer species 0 / 0 / 1
Some other Black-capped Petrel images from the trips:
With Parasitic Jaeger...well, chasing the jaeger might be more like it!
Atlantic Cory's Shearwaters were nice to see after just one or two on our last trips!
We only saw Sooty Shearwater on one trip, but it's a bit early for their big push and westerlies are not the best for seeing them!
Sargasso Shearwater was seen well on each trip, so that was pretty awesome! Sometimes they can be a challenge when it's choppy like it was for these trips!
Wilson's Storm-Petrels were very cooperative on each trip, which was nice for the spring!
We had just a few Band-rumpeds but at least one came close enough for photos on Saturday! It wasn't small, so not one of our summer breeders we sometimes see here in the spring, more likely perhaps a young winter breeder.
This Parasitic Jaeger was incredibly cooperative on Friday! There is an image of this individual above as well with a Black-capped Petrel.
Offshore Bottlenose Dolphins were encountered on each trip, which was nice! Here are a few images of those which have recently been split from the coastal group of Bottlenose.
There was a group of youngsters on Saturday, the adults showed up after we'd been with them for a few minutes. Pretty cool to see the "babysitter" group as Sea called it, on the surface until the adults returned from a deeper dive!
The pod we had on Sunday were spyhopping (sorry no photos!) and actively playing with the Sargassum that was around!
Sargassum Swimming Crab
Sea and a participant checking for creatures!
One of our participants showing off some sea grass that was hitchhiking in the Sargassum!
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