8 Sep 2018

18 Apr 18 - St Helenan Band-rumped Storm-petrel

One of the main Bird targets for St Helena was to see & photograph some of the local population of Band-rumped storm-petrels. Band-rumped Storm-petrel taxonomy is complex. A few years ago, Band-rumped Storm-petrels were understood to breed on islands in the Tropical Atlantic & Pacific Oceans, including the Portuguese Berlengas Islands, Madeira, Canaries, Azores, Cape Verde, Ascension Island, St Helena, as well as, the Galapagos, Hawaii & islands belonging to Japan. In the last decade, studies into the breeding times of year, DNA, vocalisation & morphology have identified that there are probably three additional species which breed on the Tropical North Atlantic islands. Studies of the Band-rumped Storm-petrels which breed on Ascension Island & St Helena are only just starting, but there must be a reasonable chance of additional splits of these populations once these studies have been completed.
Heading for South West Point
A few days before we arrived at St Helena, the staff gave us the options for various tours around the island. One of the trips was a chance to visit a Band-rumped Storm-petrel colony in a small boat that could take about 20 people. I expected we would have already seen Band-rumped Storm-petrels from the Plancius & this was indeed the case. I saw eight Band-rumped Storm-petrels as we approached St Helena which were presumed to have been from the St Helena population given they were within 200 nautical miles of the island. Additionally, there had been a few seen flying past our mooring position in Jamestown Bay, but these weren't close. But by this time, I had already booked & paid for a boat trip out to the Band-rumped Storm-petrel colonies on Speery Island on the first & second afternoons. In the end, I saw so much on the first afternoon trip that that I decided to cancel the second afternoon. Room on the boat was tight & I thought I would explore more of Jamestown, whilst allowing others to enjoy the boat trip. When we got on board everybody grabbed seats at the back. I suggested to Glenn that we stay by the doors by the main cabin. No sooner than the boat had left the Plancius, then two of the Expedition staff, Martin & Christophe asked if we could stand in front of the cabin. Glenn & I were well positioned to join them, which was a good move as realistically there was only room for the four of us at the front & it looked like it would give us the best viewing position. Two or three others took up places on the side of the boat, but they weren't as well placed as us. After we returned to the Plancius, there were a few people complaining about the viewing options from the back deck, so we had chosen our position well. Another reason for not going on the second afternoon was word would have been around the Plancius that the best place was where we had been standing & it would have reduced my chances of getting this decent position again.
Glenn, Martin & myself with Filiep in the background (From right to left): Christophe took the photo before returning to stand next to Glenn
Although it was a good position for viewing, it was particularly bouncy in the seas once we reached South West Point, the imaginatively named South Western corner of St Helena. The seas were just as bouncy around the main colony of Speery Island. I ended up wedging one foot on a rope mooring point on the deck & the other one one of the wire guards on the side of the boat. For most of the next three hours, I wasn't able to change position, but it meant I was had a good stable position. This was really important as twice Martin (who was next to me) lost his footing & if I hadn't been wedged in, then I might of ended up going flying.
The St Helena coastline
It got quite rough as we reached South West Point 
I expected to see some Band-rumped Storm-petrels from the boat. What I hadn't expected that the main colony at the Speery Island had good numbers of Band-rumped Storm-petrels flying around the island during the daytime. I saw at least 500 Band-tailed Storm-petrels during the afternoon. There were also smaller numbers around Egg Island, about half way to Speery Island. Clearly, there are no avian predators to worry them. Probably the majority of Storm-petrel species in the world are only able to visit the breeding islands when it is dark, so it was a real privilege to be able to see them in the day time. Sperry Island must be around 40 metres high & so the Band-rumped Storm-petrels are generally not close. They are certainly not easy to photograph from a small boat that is rolling & pitching hard & generally all I could hope was they wouldn't be too far from the rocks behind which the camera was locking onto. It wasn't realistic to hope the camera focus would lock onto the Band-rumped Storm-petrel, unless they were against the sky. Given how few people get to see the St Helenan population of Band-rumped Storm-petrels then I've published plenty of photos in this Blog Post.
Band-rumped Storm-petrel: They are a dark Storm-petrel with the pale wing band across the secondaries to the wing bend & a noticeable white rump
Band-rumped Storm-petrel: This photo was taken immediately after the last photo, but the tail now looks more forked
Band-rumped Storm-petrel: The wing tips are pointed with dark underwings & with the white rump extending well down the sides of the rump
Band-rumped Storm-petrel: With the light catching it, it was possible to see more colouration on this second individual
Band-rumped Storm-petrel: There is even a line of very pale tips to the primary coverts on a second photo of the second individual
Band-rumped Storm-petrel: A final photo of the second individual & it now looks far more typical as the lighting chances
Band-rumped Storm-petrel: This third individual came a bit closer & produced the best photos
Band-rumped Storm-petrel: The last two photos show the subtle differences in the underwing pattern when well lit & the extend of the white on the sides of the rump
Band-rumped Storm-petrel: The final photo of the third individual
Band-rumped Storm-petrel: The fourth individual
Finally, after a good hour of travelling we reached Speery Island.
Approaching Speery Island: It looks fairly calm in this photo, but it was a lot bouncier in our small boat
The sea was very impressive at the far end of Speery Island: At times, the difference in water levels on each side of the island was over a metre
Another view looking back on the same gap at the base of Speery Island
Band-rumped Storm-petrel: There were hundreds of Band-tailed Storm-petrels flying around Speery Island & presumably some were landing to feed the youngsters
Band-rumped Storm-petrel: Speery Islamd is a barren rock, but being offshore it won't have any of the mammalian predators that are likely to be on the cliffs of the main island
Band-rumped Storm-petrel: These two individuals flying against the rock are very well camouflaged against the guano-stained rocks
Band-rumped Storm-petrel: The eighth individual
Band-rumped Storm-petrel: Another photo of the eighth individual
Band-rumped Storm-petrel: A ninth individual
Band-rumped Storm-petrel: A harsh crop of the ninth individual's head shows the tube nose
Band-rumped Storm-petrel: A rear on view of the tenth individual
Band-rumped Storm-petrel: The eleventh individual
Band-rumped Storm-petrel: This view of the twelfth individual would make a good mystery species photo in the future
There were large numbers of Band-rumped Storm-petrels flying around the top of Egg Island which we had a good look at on the way back to Jamestown. From a distance they looked more like an Asian Swiftlet species which I've seen flying around cliffs & buildings in the past. But of course, once looked at with bins it was clear they were Storm-petrels flying around the breeding site in the day time.
Egg Island was obviously fortified in the Napoleonic past: It must have been grim being based on this inhospitable rock
A few plants were trying to establish themselves on Egg Island
Another plant on Egg Island
Band-rumped Storm-petrel: Five individuals were flying around the top of the rock stack in this photo
Band-rumped Storm-petrel
Band-rumped Storm-petrel
Band-rumped Storm-petrel: A number of the individuals were calling
Band-rumped Storm-petrel: A close up of the left-hand individual
Band-rumped Storm-petrel
Band-rumped Storm-petrel: A final close up of the right-hand individual. It's not often you get to see a Storm-petrel species from underneath

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