By Dr. Becker
Mishka, a 1-year-old sea otter living at the Seattle Aquarium, is the first otter to be diagnosed with asthma. And that’s not all. She’s also the first sea otter to learn to use an inhaler to help control the condition.
Asthma is a disease in which there is recurring constriction of the airways to the lungs. Excessive amounts of mucus form in the airways, which causes them to become inflamed and sometimes ulcerated.
This leads to spasms of the muscles of the airways, which is what causes the constriction and, ultimately, difficulty breathing.
While asthma has become quite common in humans, it occurs less so in animals. About 1 percent of cats have asthma, for instance, and the condition is also sometimes seen in horses.
I see the condition most predominantly in cats, and I only use inhalers as a last choice, opting for natural alternatives to control the condition, if possible.
Most zoos and aquariums have not offered integrative medicine to their patients, something that I hope will change in the future. Asthma is rare in wild animals, however, the condition can theoretically occur in any animal with lungs, as Seattle Aquarium staff veterinarian Dr. Lesanna Lahner noted.1
Getting an Otter to Use an Inhaler Is All About the Fun
Sea otters are known for their playful personalities, so it makes sense that aquarium workers are trying to make Mishka’s use of the inhaler as “fun as possible,” including offering food rewards. You can see Mishka using her inhaler in the video above. The inhaler is actually one designed for a cat, but that hasn’t deterred Mishka. Dr. Lahner told Live Science:2
"She's very smart, and she's picking it up quite quickly … But being an otter, she's also extremely playful. So we have to work with her and with her playfulness to make it fun.”
Mishka has only lived at the aquarium for a short time. She was rescued from a fishing net in Alaska and spent several months at a rehabilitation center. Because she never learned necessary survival skills, such as foraging for food, she can’t safely be released back into the wild.
Once at the aquarium, Mishka was having difficulty breathing when smoky air from nearby forest fires blew into the area. After ruling out pneumonia or another respiratory pathogen, zookeepers took an x-ray of Mishka’s chest, which revealed thickening of her bronchial walls, as is often seen in cats with asthma. It’s not known why Mishka developed asthma or whether other otters in the wild may have the condition.
Wild Otters Exposed to Environmental Chemicals
Exposure to environmental chemicals has been associated with increasing rates of asthma in humans,3 and while I’m not speculating that this is what caused Mishka’s asthma, it is known that otters are being increasingly exposed to environmental chemicals in the wild.
Otters eat fish and crustaceans, a food source that is often contaminated with drugs and other chemicals. In 2011, research was published showing the presence of two types of non-steroidal anti-inflammatory drugs (NSAIDs) – diclofenac and ibuprofen – in otter fur collected from six counties in England.
As CHEM Trust explained, these drugs only add to the chemical load to which otters are exposed in their everyday environment.4 Polychlorinated biphenyls (PCBs), which are now banned, but formerly were used for many industrial purposes, nearly wiped out otters in Western Europe and North America between the 1960s and 1980s.
During the 1700s and 1800s, it was hunting for the fur trade, not pollution, that nearly decimated the species. While there were once at least several hundred thousand, and possibly more than one million, sea otters worldwide, there were only 1,000 to 2,000 left by the early 1900s. According to Defenders of Wildlife, there are now 106,000 sea otters worldwide, including about 3,000 in California.5
Sea Otters Have the Densest Fur of All Species
It’s no coincidence that sea otters were so highly valued for their fur; it’s the densest in the animal kingdom with anywhere from 250,000 to one million hairs per square inch.6 Sea otters have no insulating fat layer like other marine mammals, but it’s no matter – their water-repellant fur keeps them warm by trapping air and forming a special insulating layer.
Aside from their dense coats, sea otters also stand out from other marine mammals in their use of tools. The animals are known to place a rock on their chest and then smash shellfish – their food of choice – against it to crack it open.
The clever mammals will also entangle themselves in forests of sea kelp to act as an anchor while they sleep in the sea.7 This, combined with the fact that they’re one of few species known to engage in play, makes otters as fascinating as they are cute.
Unfortunately, sea otters, an endangered species, still face threats from several human factors. In addition to exposure to environmental chemicals, sea otters may become entangled in fishing nets (as was the case with Mishka). Oil spills also pose a particular danger to sea otters, because the oil causes their fur to mat.
When this happens, it no longer provides insulation, which leaves the otters vulnerable to hypothermia. Parasites and infectious disease are also risks and are thought to cause more than 40 percent of sea otter deaths in California.8 According to Defenders of Wildlife, “many of these diseases are caused or exacerbated by runoff from land-based pollution.”9
In the US, sea otters not only live off the coast of California, but also in coastal Alaska. The latter is home to 90 percent of the world’s sea otters. While the Marine Mammal Protection Act protects the creatures, prohibiting their commercial harvest, their numbers have continued to dwindle over the last 20 years.10