The minke whale is the smallest baleen whale in the Baja region, reaching lengths of up to 29 feet (8.8m). We do not always see minke whales on our 12-day Natural History Tours to Baja, although that doesn’t mean they aren’t there. Because of their small size they are not as visible from a distance compared to the larger whale species. The minke’s modest size also accounts for the lack of a visible blow under most conditions, adding to the difficulty of noticing them from afar. Most of the minke whales we see in Baja are single animals, once again making it tough to initially spot them (groups of whales are easier to see than single whales. Gray whales and humpback whales in Baja are sometimes seen in associations of two or more individuals).
Some of the minke whales we see ignore us and go about their business. Occasionally, however, we get a curious individual who circles the boat and gives us great views of the animal. If the water is calm, we can see detailed features of the whale. The traits described below will help you distinguish minke whales from other whales in Baja.
Size and shape of spout / blow: As noted, the minke whale does not usually produce a noticeable blow. In climates colder than Baja you are more likely to see the blow of a minke, as the cold air condenses the moisture in the exhalation (similar to seeing your breath on a cold winter’s day). Larger species of whales produce a visible blow regardless of local air temperature as the amount of water vapor in their massive exhalation is enough to produce a condensation cloud.
Size of animal: As mentioned, the minke whale is the smallest baleen whale in Baja and you are unlikely to confuse it with the larger baleen whale species. Among the toothed whales, the killer whale is comparable in size to the minke whale, and we do occasionally see killer whales on our trips. The minke and killer whales are easily distinguished using a variety of field characteristics (e.g., the black and white color markings on a killer whale are diagnostic).
Color: The minke whale is mostly dark gray, with some animals appearing black or dark brown, depending on individual variation and lighting. The underside of the whale is white. This “counter-shaded” color pattern (i.e., dark above, light below) is common in many open-water species, including many other cetaceans and most pelagic fishes (e.g., tuna, jacks, etc.). For identification purposes, the most important coloration feature is a white patch on both pectoral flippers, the only Baja whale with such a characteristic.
Dorsal fin: The dorsal fin of the minke whale has the classic curved “falcate” shape that we usually associate with whales and dolphins. This shape is in contrast to the lack of a dorsal fin in the gray whale and the hump-like dorsal fin of the humpback whale. The minke whale’s dorsal fin seems appropriately sized for the body, in contrast to the smaller-than-it-should-be dorsal fin of the blue whale or the dramatically over-sized dorsal fin of the male killer whale. Both Bryde’s and fin whales have dorsal fins similar in shape to that of the minke whale. Don’t let the dorsal fin fool you, as the Bryde’s and fin whales are significantly larger in body size than the minke whale. As always, account for individual variations in size and shape of the dorsal fin within a species.
Tail flukes: Minke whales almost never show their tail flukes when diving. If a curious minke circles the boat under calm conditions, we can sometimes get a good look at the flukes. The flukes are similar in shape to that of the blue whale (i.e., wide and tapered) but obviously scaled down in size.
Species-specific traits: The unique traits of the minke whale (as compared to other Baja baleen whales) are the relatively small body size and the white patches on the pectoral flippers. Also, the minke whale has a pointier snout than the other whales in its family (family Balaenopteridae, which includes the blue, fin, Bryde’s and humpback whales).
Behavior: The minke whale does not normally exhibit the demonstrative behaviors that we see from humpback whales. Minke whales are known to breach on occasion, but I’ve never seen a breach in over ten years of whale watching in Baja. One behavior I find distinctive of minke whales is the manner in which they surface for air. From what I’ve seen, minkes seem to “pop” to the surface at a relatively steep angle, such that the front of the head, including part of the lower jaw, breaks the surface. Plus, they seem to be at the surface for just a moment, less time than the other baleen whales.