14 and 15 July 2013
The ferry from La Paz to Mazatlán provides a good opportunity to see some seabirds, although unfortunately the ferry leaves in the evening and arrives in the morning so there are just a couple of hours of light to bird on either end. Nonetheless, we saw the expected Least and Black Storm-Petrels, Sooty and Pink-footed Shearwaters, and Brown and Blue-footed Boobies. We didn’t actually see Black-vented Shearwater though we’d seen them several times in Baja from shore and from boats. Additionally we found 3 Red-billed Tropicbirds in the evening once we were out of La Paz bay. The following morning, about 20-30 miles offshore from Mazatlan, we got a bit of excitement as we both picked out a Storm-Petrel that seemed intermediate in size between Least and Black, had a bit different flight pattern and, as it came closer to the boat, showed a white rump. Some pictures confirmed that it was a Wedge-rumped Storm-Petrel! Shortly thereafter 2 Red-footed Boobies flew in and hitched a ride on the ship for a while, a third Red-footed Booby flew past the boat later. The biggest surprise, however, came about 15-20 miles due west of Mazatlan when we saw two small gadfly Petrels. They were distant but were small with medium gray backs and clean white undersides. They were actively plucking food from the surface while flying with floppy deep wing beats in quite calm conditions. While we can’t be certain, our impression is that they were far too small and slight for Juan Fernandez Petrel and that they were most likely the somewhat more expected Cook’s Petrel. Unfortunately we didn’t get any pictures.