Indian Ocean January 2013, Tamatave – Port Louis

The last days before our volunteering on Mauritius began were spent on the Indian Ocean. Instead of flying the Mauritius Shipping Corporation (http://www.mauritiusshipping.intnet.mu/) offers the possibility to go by boat. The crossing takes three days and is cheaper than a one-way ticket, however the Corporation offers only one crossing per month. We paid 250 euro for a one-way ticket in second class and I think it is absolutely worth it. The fare includes all meals (very decent meals) and it gives you the opportunity to see some seabirds. However make sure you don´t get sea sick, for the Indian Ocean is a rough sea. We tried Sea Bands (http://www.sea-band.com/), but we still felt dizzy and nauseous, especially when the ship encountered a tropical storm on the open sea.

We found the open sea between Madagascar and Reunion very, very empty and did not see much, just a single tubenose and some flying fish. This tubenose however deserves special attention. This species is one of the rarest sea birds in the world and breeds on La Réunion. Seeing the species at La Réunion is close to impossible, even though many people claim to have seen one. I´ve spoken a lot with the researchers who work on this species on La Reunion. One of them has worked on them for 11 years and has seen one at sea and had around 10 crashed individuals in his hand. The colony of this petrel is still unknown, but is most likely located in the south of the island. The only realistic, but slim chance of seeing a Mascarene Black Petrel is taking a boat to the sea, preferably between St. Pierre and St. Louis. The best time of the year to do this is between February and April. The researcher who saw a Mascarene Black Petrel here however needed 10 to 15 attempts to succeed. There are even sightings of Mauritius, but these are probably all misidentified dark morph Trindade Petrels (see Round Island). So it is obvious that this species is extremely rare. The only reason that people know that it still exists are the one or two juveniles that are rescued on la Réunion each year. The pictures below show a good candidate Mascarene Black Petrel, according to the scientists, but I´m defenitely not sure and will look into it further. The bird was flying very close to the water with slow, but three to four strong wing beats interspaced by gliding pauses. The bird was rather small and completely dark without any obvious plumage features. Unfortunately it stayed far from the boat and therefore the pictures are rather crappy.
After looking into it further and asking several tubenose specialists for help, it turns out that this bird is most likely a Jouanin´s Petrel. 

Jouanin´s Petrel (Bulweria fallax)

In the right time of the year encounters with whales in this stretch of the ocean are apparently not uncommon and the captain is even willing to stop the boat so the passengers can enjoy these giants for a while. The waters directly around Reunion proved to be more productive with 50 Barau´s Petrels, several hundreds of Tropical Shearwaters and 50 Wedge-tailed Shearwaters. A long stop in the port of Reunion produced also some Mascarene Swiftlets.  Most tubenoses were observed at dusk around Reunion when the birds come back from the sea to the land.

Barau´s Petrel (Pterodroma baraui)

Barau´s Petrel (Pterodroma baraui)

Tropical Shearwater (Puffinus bailloni)

Tropical Shearwaters (Puffinus bailloni)

Wedge-tailed Shearwater (Puffinus pacificus) (pink-billed variant)

I can highly recommend doing this boat trip instead of flying, for it crosses an area rarely covered by birders and who knows what hangs around there. Indian Yellow-nosed and Salvin´s Albatross are definitely among the possibilities. Apart from that, we found our boat, the MS Trochetia, a very comfortable boat, especially compared to Malagasy taxi-brousses.

Open Ocean (picture made by Anna van der Kaaden)