The Chilean dolphin, aka tonina, hails only from the coastline of Chile. They are found nowhere else, sans an extant (unverified) population in Argentina. These dolphins face the threats of marine & freshwater aquaculture, overfishing, and bycatch (getting caught in fishing lines and nets). They are listed as Near Threatened by the IUCN, and their population is decreasing.
First the Stats…
Scientific name: Cephalorhynchus eutropia
Weight: Up to 125 lbs.
Length: Up to 5.7 feet
Lifespan: Presumed to be up to 20 years
Now on to the Facts!
1.) Due to their blunt head and small size they are often misidentified as porpoises.
2.) Their dorsal fin and flippers are small in relation to their body size, compared to other dolphins.
3.) They have up to 34 teeth in their upper jaw and up to 33 teeth in their lower jaw.
4.) Chilean dolphins are typically found in smaller pods of up to 10 individuals, with rare sightings of larger pods being recorded.
5.) The fact that they frequent riverine and estuarine ecosystems makes Chilean dolphins highly vulnerable to habitat loss from both upstream and coastal river basin degradation.
But wait, there’s more on the Chilean dolphin!
6.) Limited distribution and generally inflexible habits of cultural degradation causes them to be quite vulnerable to population fragmentation and loss in the event of increasing human-based activities.
7.) Although undocumented, it is suspected that females undergo up to a 12 month gestation (pregnancy) that yields a single calf. This information is surmised from the Hector’s dolphin.
Did you know…?
In the earlier part of the 20th century, these dolphins were typically referred to as the black dolphin. But this was due to spotting them as great distances or from beached specimens, both of which appeared to have darker skin. Their skin is actually a mixture of greys.
8.) Like other dolphins, these critters engage in unihemispheric slow-wave sleep (USWS). This is where they are able to put half of their brain to sleep, while the other stays alert for predators and allows them to breathe.
9.) Just as is the case with other dolphins, they also utilize echolocation. This is where they will produce specific sounds that bounce off of objects in the water and return a signal to the producer of the sound, which helps to better determine friend, foe, and food.
10.) These dolphins are presumed to be preyed on by sharks and orcas.
Now a Short Chilean Dolphin Video!
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Some source material acquired from: Wikipedia & IUCN
