On 9 October 2013 in the late afternoon Cindy and I set sail from Cabo San Lucas for Puerto Vallarta. We were on a Carnival Mexican Riviera Cruise. At around 4:30 pm about 30 miles out of Cabo (22.6581, -109.4678), Cindy and I observed our first Tahiti Petrel. The bird came very close the ship and Cindy and I both had excellent views. I had never seen Tahiti Petrel and Tahiti Petrel was not on my radar for Baja, but surprisingly I knew immediately what it was from seeing this species in field guides so often. As we observed the bird I shouted out field marks to Cindy as I often do for corroboration. I called out, look at the head, it is entirely black, including the chin, neck and throat. The underwings are dark and belly white. The upperside is entirely dark and the tail fairly long, with paler markings giving the tail some contrast to the rest of the upperside. By this time Cindy was chiming in with a few shout-outs of her own. After about 30 seconds or so, the bird flew around the bow of the ship and we lost it.
After the shock wore off, I started consulting the references we had brought along. The new Howell seabird guide proved to be quite useful. It was clear from the references we had just seen a Tahiti Petrel. Later on, as the light faded and day turned to night, I called Paul Lehman to discuss what I had just seen. Partly to discuss field marks and partly to share my excitement. I had just talked to Paul a couple of days before about the Masked Boobys we had seen as we were leaving the Long Beach Cruise Terminal, and I knew Paul would be interested in hearing about a Tahiti Petrel. That evening and the next day I devoured all I could on the identification, status, and giss of Tahiti Petrel. I gleaned 3 seabird guides and the Howell Field Guide to the Birds of Mexico.
Fairly large seabird about Sooty Shearwater size, with long straight wings, dark brown above, with paler uppertail-coverts, and white underparts which are clearly demarcated from the dark brown upper chest, neck and head. The central part of the dark underwing bears a thin, pale stripe. The tail is fairly long and tapered.
On 11 October 2013 dawn broke and we awoke out at sea en route back toward Cabo San Lucas from Puerto Vallarta. At around 10:00 am I noticed a couple of large seabirds. I quickly realized they were both Tahiti Petrels and I tried to study as many marks as I could as the birds faded into the distance. I could see the dark upperparts, with paler brown upper tail, dark underwings, gleaming white belly and undertail, and distinctive demarcated black head, long straight wings and fairly long tapered tail. At one point one of the birds stalled and fanned its tail showing a distinctive brown and white mottled tail. It appeared the inner webs must have been white or lighter in color, since the tail appeared more mottled and lighter brown when spread. About an hour later, I spotted another Tahiti Petrel. This time the bird was flying parallel to and in the same direction of the boat, and at about the same speed, around 20 knots. Although the bird was fairly distant, a spotting scope offered excellent views. Since I had
studied up on Tahiti Petrel the previous two nights, I was able to walk through all of the field marks in my mind as I observed. Does it have an all dark head, yes, what about the dark underwings with subtle white mid line, yes. How about the all dark upperside with a paler tapered tail, yes. I went over and over the tell-tale field marks as I watched the bird off and on (mostly on) for about 10 nautical miles, about 30 minutes. After this lengthy period of careful scrutiny, I had absolutely no doubt that this and the other 3 birds were Tahiti Petrels. Unfortunately, I could not get any photos. I tried a few times, but it was a matter of study the bird in the scope, or waste precious viewing time struggling to find the bird in the camera's view finder. After a couple of photo attempts, I gave up to study the bird in detail. Soon after the sighting I took notes and made some drawings of what I had seen.