Ogasawara Islands Pelagic

Bonin Petrel

The Ogasawara (formerly Bonin) Islands are named after Ogasawara Sadato, one of whose descendants claimed he had discovered them in 1593.  Wikipedia has an interesting account of the history of these islands here:-

http://en.wikipedia.org/wiki/Bonin_Islands

With ferries from ports near Tokyo, these days tourists visit for the clean, subtropical breezes and other natural charms of the area, such as dolphins and Humpback Whales. There is plenty of sport diving in the area, too.

Fortunately, this Humpback was a good distance from the boat. It did us the courtesy of breaching three times, so we all got a chance of a photo.

Being close to the edge of the continental shelf, and an area with many rocky islets, the whole Ogasawara island chain is good for seabirds, too.  

More frequent sightings of Bonin Petrel meant we were getting closer to the main islands, Chichijima and Hahajima.

Our route was planned with locally-breeding seabirds  in mind, with our two sought-after shearwaters, namely Bannerman’s and the newly-discovered Bryan’s Shearwater topping the list. With these in mind, we arrived off the islet of Higashijima (literally “East Island”, just off Chichijima) in the early evening of May 3rd.

http://blogs.scientificamerican.com/extinction-countdown/amazing-discovery-nearly-extinct-bird-found-breeding-in-japan/

However a full moon had already risen, and there were no “rafting” seabirds waiting to fly back to their burrows. In fact a search of the seas in the area revealed that there were hardly any birds around at all. 

We had no intention of trying to land on the island itself to go looking for them. Obviously, crashing about on an active seabird colony would have been totally out-of-order. So, shearwaterless, we sailed overnight to Hahajima, 80 km to the south.

We had scheduled a morning ashore.

Back in the 1980s I had a copy of the WBSJ  Field Guide to the Birds of Japan and was fascinated by the island endemic then known as Bonin Honeyeater. Hahajima was the island to see it, but I wondered if we would have to do manly hikes all over the island in order to get a glimpse of one. 

I need not have worried. A few yards from the quay was a grassy bank where a pair of Bonin Honeyeaters were collecting nesting material.

One flew across the road and picked at the ropes on a boat parked on a trailer.

(Most books now call this the Bonin White-eye.  In ten years' time, will it be known as the Ogasawara White-eye ?) 

Elsewhere, the local races of Brown-eared bulbul, Oriental Greenfinch and Black Woodpigeon were present, as were several Blue Rock Thrushes.... 

Replete with souvenir Hahajima T-shirts, (motto: “Not civilised but excitable”) we returned to the Sauvage.

In the late afternoon we had a welcome example of "visible migration" with these Ruddy Turnstones heading for the islands we had just left.

The following morning a spectacular sunrise was followed by a chumming session. After about an hour, a total of 70 Matsudaira’s Storm-petrels were attracted to the “slick”. 

They hovered like butterflies over the water. It's what Storm-petrels do.

The Matsudaira’s were joined by a single Wilson’s Storm-petrel, the white rump really standing out in the crowd.  Wilson’s is a southern-hemisphere breeder, but is regular in the seas off Japan. Another potential addition to the Hong Kong list...... !!

Matsudaira's Storm-petrels breed in the Ogasawara and also in the Iwo (Volcano) Islands, but many winter in the Indian Ocean, so it's another possible find off the coast of southeast China.

Meanwhile, we headed on towards the southernmost point of our sea journey.


End of Part II

Izu Islands Pelagic

In spring 2013 we sailed between New Zealand and Papua New Guinea on the “Western Pacific Odyssey” (Heritage Expeditions). I blogged about that trip here:

http://johnjemi.blogspot.hk/2013/05/western-pacific-odyssey-2013-part-1-all_20.html

There were a wide variety of seabird enthusiasts on the trip including Canadian Dr. Kirk Zufelt, whose website “Pelagic Odyssey” makes his interests plain.

http://www.pelagicodyssey.ca

Later in 2013 Kirk contacted us to say that he was organising a trip to see the seabirds of the Japanese Izu, Ogasawara and Iwo island chains. Sparsely populated and volcanically active, these islands form a 1,200 km chain south of Tokyo.

A lot of the anticipated seabirds were of regional interest to us, with Streaked and Short-tailed Shearwaters, for example, on the Hong Kong list. Some of the other possibilities included potential vagrants to Hong Kong, so we jumped at the chance.

The vessel chosen by Kirk for the trip was the expedition Yacht “Sauvage”, owned and crewed by the very capable Didier and Sophie Wattrelot. Website here:

http://www.sailing-yacht-sauvage-expedition.com/index.html

With only six places available, the remaining participants were Mike Danzenbaker (California), Dr Colin Rogers (Adelaide) and Glenn McKinlay (Palau).

On 27th April we arrived at the dockside of Misaki Port and boarded the Sauvage in the early evening.

Underway in the morning, we could see that Streaked Shearwaters were abundant in the waters just south of the Japanese mainland, as expected.  

This species “readily follows fishing boats” according to the bird books, and we saw some good examples of this early in the voyage.

The pole-fishing tuna boats attract tuna to the surface with live sardines and the shearwaters obviously find this irresistible too.

Kirk and Mike had arrived in Japan bearing a substantial quantity of fish oil, and this, stiffened with squid oil, was dripped from the rear of the Sauvage.  The resultant slick did get the attention of many seabirds, - this Leach's Storm-Petrel, for example, - 

but we could never compete with the volume of fish product scattered by commercial fishermen. Fortunately, for much of our journey, there were no other boats in sight.

By the late afternoon of the first day Jemi and I got our two “Northwest Pacific Albatross Ticks” at the same time with two Short-tailed and three Black-footed in a group on the water.

A few Japanese Murrelets had been tallied by the time we passed Ojima  at the end of the day. I should mention here that "jima" and "shima" in place names means "island"

Near Miyakejima we had more murrelets near Sanbondake rocks, a known breeding site.  There were not many murrelets around, though and the Peregrines we saw (at least three) must have found the murrelets easy to catch.

After four days of sailing (and some character-building sea conditions) a grey dawn found us to the north of Torishima, another charismatic seabird island, known as the main breeding site for Short-tailed Albatross, which were nearly hunted to extinction the 1920s. The Yamashina Institute for Ornithology has an interesting account of the commercial exploitation of the Albatross population from 1886 here:-

http://www.yamashina.or.jp/hp/english/albatross/history_al.html

The remains of the Weather Station, abandoned after a volcanic eruption in 1965.

As we circled the island the weather cleared, revealing the colour of the rocks on the island, and rafts of albatrosses on the sea surface. The present population of Short-tailed Albatross is estimated at about 2,000. Several hundred Black-footed Albatrosses also breed on Torishima.

We also saw a nesting colony on one of the scree slopes of Torishima, a site called Tsubamezaki. Over two hundred unfledged young in were in view, some practising their wing-flapping on tussocks of grass. 

Japanese Ornithologists monitor this colony, and efforts have been made to stabilise the slope that the birds use. The ornithologists are also attempting to decoy the albatrosses to use a less steep, better vegetated area of the island.

Other birds in the area included Brown Boobies,

our first Wedge-tailed Shearwaters

and this fly-by South Polar Skua. 

 From Torishima it was two more days sailing to the Ogasawara (Bonin) Islands.