I recently took the fall pelagic birding trip out of Dana Point Harbor. Recent sightings of a Red-billed Tropicbird in the Santa Barbara Channel and the presence of hurricane systems south of us off the west coast of Baja suggested that the fall pelagic might be a really good trip. There had already been greater than usual numbers of Craveri’s Murrelets in the channel, and many people were on the boat specifically looking for that species. Plus, with September being the peak of Blue Whale occurrence in the channel, we knew beforehand that this trip could end up being dominated by cetaceans rather than birds. In the end, all of those expectations were met. Well, except for the tropicbird… Rats!
The fall pelagic trip began with the close views of Black Oystercatchers feeding at the water line of the Dana Point jetty, and the expected gulls, terns, cormorants and pelicans perched on the breakwater or feeding over the harbor mouth. Once we left the harbor, we found the expected large flock of Black-vented Shearwaters (Puffinus opisthomelas). These small shearwaters breed in burrow nests on Guadalupe, San Benito and Natividad islands offshore from northern Baja. Black-vented Shearwaters are only found in the Pacific Ocean, almost exclusively along the North American coast. Black-vented Shearwaters come closer to land than most shearwater species, and are frequently observed from shore, feeding in densely packed flocks mostly on small fish. For this reason, Black-vented Shearwater feeding flocks are often associated with pods of dolphins or whales because the mammals drive the prey fish to the surface. We saw several pods of Common Dolphin, and Blue Whales in close proximity to masses of feeding Black-vented Shearwaters. The weather on this particular trip was mostly gray, overcast and cool. The lack of light and the distance of many of the birds made me really appreciate the impressive light-throughput and definition afforded by the 10×42 Zeiss Victory HT binoculars I was using.
This fall pelagic also featured a few Pink-footed Shearwaters (Puffinus creatopus) mixed in with the Black-vented Shearwaters. Pink-footed Shearwaters are natives of the southern hemisphere, breeding colonially in burrows on forested slopes on islands off the coast of Chile. With their larger wings, Pink-footed Shearwaters are more efficient flyers than Black-vented, allowing them to cover longer distances and glide a much higher percentage of the time. Pink-footed Shearwaters often use the same “dynamic soaring” posture that albatrosses employ on their trans-oceanic sojourns. Pink-footed Shearwaters occur in two different color phases, light and dark one. The dark phase presents potentially thorny identification issues by making them confusable for other, rarer seabirds. We seldom see the dark phase birds here. On this bird, you can clearly see the dark-tipped, pinkish bill and the nasal tubes through which these birds excrete excess salt they ingest with the sea water they drink.
In Orange County, there is always the chance of seeing good numbers of storm-petrels on a fall pelagic trip. Here, we usually see mostly Black Storm-Petrels (Oceanodroma melania), with a scattering of Least and Ashy Storm-Petrels. On this particular trip, we had roughly equal numbers of Black and Least Storm-Petrels (Halocyptena microsoma), though invariably, these birds appeared well away from the boat, and refused to come closer, even when tempted with offerings of fish oil from the stern. We did have about 20 Craveri’s Murrelets (Synthliboramphus craveri) and everyone got good looks at these charming little birds. But the biggest stars of this trip (literally!) were cetacean: we observed three whale species and two species of dolphins. Early in the trip, we encountered a fairly large pod of Common Dolphins (Delphinus capensis). The name Common Dolphin references the fact that they are found in all seven of the world’s major oceans, rather than being a commentary on their frequency. There are two Common Dolphin varieties, the Long-beaked and Short-beaked. Of these, the Long-beaked are most often found in shallower nearshore waters while Short-beaked Common Dolphins tend to be found in the deeper waters of the open ocean. Both species are somewhat smaller (6 to 8 feet) and have white markings on their sides and at the base of the dorsal fin. Common Dolphins are friendly and curious, often swimming from farther away to approach a boat, and riding the bow pressure wave with apparent joy. Common Dolphins are also quite acrobatic, and often leap completely out of the water. Shortly after leaving the dolphins, a Minke Whale was seen. Unfortunately, this one was less friendly than the one seen on the earlier spring trip. Later, we came upon a small pod of Bottlenose Dolphins (genus Tursiops). Bottlenose Dolphins are larger (7 to 13 feet long), uniformly gray in color, and much less likely to engage in aerial displays. Recent research indicates that in the near Pacific, there are at least two species of bottlenose dolphins, the Common and the Indo-Pacific. As those two species are difficult to separate in the field, we aren’t calling these.
When we got nearly to the Newport harbor jetty, we got perhaps the biggest thrill of this fall pelagic trip in the form of several loose groups of feeding Blue Whales (Balaenoptera musculus). As luck had it, the whales approached the boat while feeding so we got rather close to them. We heard the explosive exhale when they spouted and watched them lunge-feed at the surface, taking in a massive volume of water in a single swallow. Blue Whales use their baleen filter plates to extract the krill on which they feed from the water. When lunge-feeding, the whales often turn on their sides so that the tip of one tail fluke protrudes from the water, or even invert completely so that the ventral pleats on the throat are visible, as shown here. At the same time we saw the feeding Blue Whales, there were also a few Fin Whales (Balaenoptera physalus). Unlike the Blue Whales, the Fin Whales kept their distance from the boat, which is fairly typical behavior for this species. They are readily distinguished from Blue Whales if seen clearly because their dorsal fin is much more prominent than that of the Blue Whale. Both Blue and Fin Whales are currently listed as endangered species, with estimates of 5,000 to 12,000 Blue Whales worldwide, compared to 40,000 to 50,000 Fin Whales. Blue Whale populations do seem to be bouncing back well now that large scale hunting of them has ceased. What a privilege to see the two largest animals on the planet in the same day!