Mammals


Humpback Whale (megatera novaeangliae; Spanish: Ballan Jorobada o Yubarta)

One of the larger whales with adults ranging in length from 12-16 meters (40-50 feet) and weighing approximately 36,000 kilograms (79,000 pounds), these migrating whales pass just off shore from November through April. They are very acrobatic and often breach and slap the water. The humpback has a distinctive body shape with unusually long pectoral fins and a knobby head.

Long targeted by whalers, the humpback population fell by 90% before a whaling moratorium was introduced in 1966. Since then their numbers have rebounded to around 80,000, although many still die each year from entanglement with fishing gear and collisions with ships. Humpbacks are found in oceans worldwide and typically migrate up to 25,000 kilometers each year; during the summer they feed in polar waters on a diet of krill and small fish and in winter they move south to tropical waters to breed and give birth in winter. During winter, they do not feed and live off their fat reserves.


Dolphin (family Delphinidae; Spanish: Delfin)

Dolphins are marine mammals closely related to whales and porpoises. There are almost forty species in seventeen genera. Dolphins evolved recently, about 10 million years ago. Their ancestors were originally land animals who retreated to the seas about 50 million years ago. Dolphins are considered among the most intelligent animals, although measuring intelligence in a species with different sensory and cognition systems is difficult. But for example some dolphins teach their young to use tools. The dolphins break off sponges and use them to protect their snouts while foraging. This knowledge is passed from mothers to daughters and is not genetically inherited, but specifically taught. Dolphins also communicate using a variety of clicks, whistles and ultrasonic echolocation.

Because dolphins need to come up to the surface to breathe, they do not sleep in the same way land mammals do; generally they sleep with only one brain hemisphere in slow-wave sleep at a time, maintaining some amount of consciousness with the other hemisphere.

The most common dolphins on the Pacific side of Mexico are the Orca or Killer Whale (Spanish: Orca), Pantropical Spotted Dolphin (Spanish: Delfin Pintado), Eastern Spinner Dolphin (Spanish: Delfin Tornillon); Striped Dolphin (Spanish: Delfin Listado); Long-beaked Common Dolphin (Spanish: Delfin Comun de Rostro Larago); Pacific White–Sided Dolphin (Spanish: Delfin Lagenorringo); Common Bottlenose Dolphin (Spanish: Delfin Nariz de Botella). Dolphins live in social groups called pods with up to a dozen members. You occasionally will see a pod cruising the beach just outside the surf line. When food is abundant, they sometimes form superpods offshore aggregating hundreds of individuals.


Armadillo (Dasypus novemcinctus; Spanish: Armadillo; Nahuatl: Ayotochtli)

This is the same nine-banded, long-eared, hairless, armored creature that is famous as road kill in Texas. In Mexico, its usual demise is different. Here it is prized for its meat. Armadillos are avid diggers, living in burrows in moist ground and pursuing grubs and insects with their sharp claws. Their frequent fate as road kill is linked to an unfortunate tendency to jump straight into the air when startled. The average armadillo’s vertical reach is approximately the same as the height of an average pickup truck bumper.

Scientist use nine-banded armadillos because of a quirk in their reproductive systems. They are unique among mammals in having four genetically identical quadruplets born in each litter. Because they are always genetically identical, the quads are good subjects for scientific, behavioral and medical tests that need consistent genetic makeup in the test subjects.


Coatimundi ( Nasua narica; Spanish: Tejon or Pisote)

The coati is a member of the raccoon family sporting a long snout with somewhat pig-like features and bear-like paws. Ring-Tailed coatis have either a light brown or black coat, with a lighter under-part and a white-ringed tail in most cases. All coatis share a slender head with an elongated, slightly upward-turned nose, small ears, dark feet and a long, non-prehensile tail used for balance and signaling. They are about the size of a large housecat with males larger than females. Coatis are omnivores; feeding mainly on fallen fruit and invertebrates. They walk on the soles of their feet like Grizzly bears and have strong limbs for climbing and digging. They are quite intelligent and a coati communicates its intentions or moods with chirping, snorting or grunting sounds. Different chirping sounds are used to express joy during social grooming, appeasement after fights, or to convey irritation or anger. Snorting while digging, along with an erect tail, states territorial or food claims during foraging. Coatis also use special postures or moves to convey simple messages; for example, hiding the nose between the front paws as a sign for submission. In this area, you sometimes see them at night on their nocturnal hunts.


Opossum (Didelphys azarae; Spanish: Tlacuache)

Again Mexico shares this species with her northern neighbor. It is a marsupial and not particularly revered in this region. A Mexican author described it as “an unattractive, slow-witted nocturnal creature with a long muzzle, rather fearsome-looking teeth, a coarse, variable, yellowish and gray coat, striped or blotched and a prehensile tail, long, naked and pink.” Nonetheless it does have few claims to fame; more teeth than any other mammal (up to 52) and litters of 10-20 offspring produced after a gestation period of only 13 days.