Vaquita Porpoise

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Vaquita Porpoise

The vaquita is the smallest of the cetaceans, a group that includes whales, dolphins and porpoises. It is also by far the most endangered, and it is estimated there may be as little as 30 of these marine mammals left in the wild.


Content List

1. Scientific & Common Names

2. Characteristics

a. Breeding

b. Behavior

3. History

4. Present Status

5. References


Scientific & Common Names

Kingdom - Animalia

Phylum - Chordata

Class - Mammalia

Order – Artiodactyla

Infraorder - Cetacea

Family – Phocoenidae

Genus - Phocoena

Species – P. sinus

Common Name – Vaquita (Spanish for “little cow”), Cochito (Spanish for “sow” or “pig”), Gulf of California Porpoise, Desert Porpoise, Gulf Porpoise


Characteristics

Vaquita are quite small, even for porpoises, and don’t exceed five feet in length. They have a thickset body type typical of porpoises, though their dorsal fins are relatively large. Like most of their kin they lack a pronounced “beak”. They are gray above, with lighter coloration below, and have dark markings at the front of their face around the mouth, as well as a dark ring encircling the eye. There may also be dark stripes running from the lower jaw to their pectoral fins, though these are not always present.


Breeding

Not much is known about the breeding habits of the vaquita, though it is believed to be similar to the harbor porpoise in this respect. They are thought to breed in the early summer, with gestation lasting about 11 months. Birthing happens in early spring, February to April, though Vaquitas probably do not breed every year. They typically give birth to a single calf, and females will nurse their young for up to eight months.


Behavior

The vaquita is a very cautious animal that is not easily observed in the wild. Thus, many of its habits are not well known. It tends to travel alone or in small groups, and it avoids boats and other vessels. When it surfaces to breathe it disturbs the water very little, and it often submerges for long periods of time.


History

The vaquita is the only species of porpoise that lives in warm waters, and is only found in the northwestern tip of the Gulf of California in Mexico.

While it is not known exactly how abundant they were prior to their current decline, the estimated size of the population in the 1930s is believed to be around 5,000. Though vaquita are not specifically targeted for hunting and, they were unfortunately often caught in nets targeting another species: a fish known as the totoaba. From the 1920s to the 940s, the commercial fishery for totoaba caused immense damage to the vaquita population. The fish is now itself endangered due to overfishing, and commercial fishing was stopped in the 1970s, though it is still hunted illegally, causing both the totoaba and vaquita to decline in numbers.


Present status

Vaquita are critically endangered, and there may be as few as 30 animals still in the wild. Between 2011 and 2016, the population dropped by 90%.

The swim bladder of the totoaba is a delicacy in China, so despite the fish’s protected status, an illegal fishery is thriving in the Gulf of California. Vaquita are caught in these illegal gillnets, causing immense harm to their population. With their numbers hitting such tragically low numbers, breeding rates are also greatly reduced, making recovery even more difficult.

Despite a number of emergency efforts to curb the illegal use of gillnets in the vaquita’s range, their numbers have not rebounded and they are still in steady decline. Captive breeding programs are in development, though this is a difficult task due to the elusive nature of this porpoise and their poor track record in captivity.


References

Princeton Field Guide: Whales, Dolphins and Other Marine Mammals of the World, Jarrett & Shirihai, 2006
Guide to Marine Mammals of the World; Reeves, Stewart, Clapham, Powell; 2008
Whales, Dolphins and Porpoises: The Visual Guide to All the World’s Cetaceans, Mark Carwardine, 1995
https://en.wikipedia.org/wiki/Vaquita
http://porpoise.org/save