Otter vs Beaver in Chinese: 5 Key Differences to Tell Them Apart (2026)

"Is that an otter or a beaver in the water?" I've heard this question more than once in front of zoo signs.

Most people get stuck not because of their eyes, but because of the names. Otter is 水獺 in Chinese, but beaver is written as 河狸, 海狸, or 水狸—you check three websites and get three answers, so of course it gets more confusing.

This article skips trivia and focuses on methods you can use to tell them apart in 10 seconds the next time you see a photo or a live animal.

Otter vs Beaver: Quick Chinese Overview

Here's a quick look at the basic differences; we'll break them down one by one below.

Feature	Otter (水獺)	Beaver (河狸)
Common Chinese names	水獺	河狸, 海狸, 水狸 (inconsistent translations)
Classification	Carnivora, Mustelidae, Lutrinae	Rodentia
Tail	Long and rounded, tapering to a point	Flat, elongated oval, like a paddle
Teeth	Typical carnivore teeth	Large orange incisors, similar to a squirrel's
Webbed feet	Webbed between toes	No webbing on front limbs; hind limbs fully webbed
Signature behavior	Fishing, agile swimming	Gnawing branches, building dams

This article uses five identification points: classification, tail, teeth, webbed feet, and behavior.

Identification Point 1: Start with Classification—Mustelidae vs Rodentia

This is the most fundamental step, and the one most often skipped.

Otters belong to the order Carnivora, family Mustelidae, subfamily Lutrinae. There are 13 extant species in 7 genera. They are semiaquatic, four-legged animals with webbed toes.

Beavers belong to the order Rodentia, making them relatives of rats and squirrels.

In other words, they only share the fact that they live near water and can swim—their lineages are very distant. Because of this classification difference, their teeth, tails, and diets all differ as well.

Identification Point 2: The Tail Is the Fastest Clue

If you can only look at one body part, look at the tail.

A beaver's tail is flat and elongated oval, like a paddle. Many people describe it as "obviously not a rat's tail."

An otter's tail is long and rounded, tapering to a point. It acts as a rudder while swimming, allowing the otter to turn very agilely in the water.

Note that in Chinese there is also "海狸 (Coypu)," which refers to a different animal (the coypu or nutria). Its tail is thin and long like a rat's, and it lives near water, in brackish marshes, and salt marshes. The biggest difference between it and the dam-building beaver is precisely the tail.

Identification Point 3: Tooth Color Holds the Answer

The second reliable clue is the incisors.

Beavers are rodents and have large orange incisors like a squirrel's—tools for gnawing tree trunks.

Otters are carnivores, with teeth typical of a predator; they lack those large orange incisors.

The advantage of this feature is that even if a photo only shows the side of the head, you can often still tell.

Identification Point 4: Webbed Feet and How They Swim

Many people assume that "semiaquatic + webbed feet" means the same animal, but the webbing is distributed differently.

Beavers have no webbing on their front limbs, but their hind limbs are fully webbed.

Otters have webbing between the toes of all four feet. In giant otters, for example, you can see webbing between the toes on all four limbs.

Additionally, otters have a streamlined body—graceful and agile—and move noticeably more quickly in the water than beavers.

Identification Point 5: What They're Doing in the Water

Behavior is the identification method that requires the least close-up footage.

Beavers are most famous for building dams. If you see small mud dams or lodges made of dead wood in a stream, they're usually a beaver's handiwork.

Otters are expert fishers and carnivorous, feeding mainly on fish, but also shrimp, crabs, frogs, and small mammals; sources often describe them as nocturnal.

Simple memory aid: see "engineering" and think beaver; see "chasing fish" and think otter.

Don't Miss the Third Name: Sea Otter

When you search for "otter," sea otters often pop up too.

The sea otter is another animal frequently compared with otters and beavers. It also has "獺" in its Chinese name, but its habitat and appearance differ from both. When three pictures are lined up together, it's often the one most likely to be misidentified.

So when identifying, don't just look for "獺" in the name—go back to the three features: tail, teeth, and webbed feet.

One-Line Memory Aid

Otter: long pointed tail, webbed feet on all four legs, chases fish.

Beaver: flat paddle tail, large orange incisors, builds dams.

海狸 (coypu/nutria): thin rat-like tail, a different species—don't confuse it with the beaver.

Frequently Asked Questions

Q1: Is "beaver" 河狸 or 海狸 in Chinese?

Both are used, and there's also the spelling 水狸. Chinese translations are not standardized, so it's better not to rely on names—use classification and physical features instead.

Q2: What's the biggest difference between an otter and a beaver?

Classification. Otters are carnivores (Mustelidae); beavers are rodents. This affects their teeth (beavers have orange incisors), tails (beaver flat, otter long and pointed), and behavior (beavers build dams, otters catch fish).

Q3: Is a flat tail always a beaver?

Generally yes, but note that the "海狸 (coypu/nutria)" has a thin, long tail like a rat's—completely different from a beaver's broad flat tail.

Q4: Do both have webbed feet?

Yes, but in different places. Beavers have no webbing on the front limbs and full webbing on the hind limbs; otters have webbing between the toes of all four feet.

Q5: Why are they often confused?

Because both are semiaquatic, four-legged animals with webbed toes, and their silhouettes look similar from a distance. Combined with overlapping Chinese translations, you get the "three websites, three answers" situation.

Q6: What should I do if I see them in the wild?

Keep your distance, don't feed them, and don't approach dams or lodges for photos. Observe with your eyes and camera only.

References

• 【動物世界】Beaver 水貍 還是 Otter 水獺？(榮登聯合新聞網首頁，生活消費／貼心下午茶) - 在水一方～林彬的玫瑰世界 - udn部落格
• 海獺、河狸與水獺，你知道誰才是建築水壩的高手嗎？！ | 生活發現 | 妞新聞 niusnews
• 【我才跟他不一樣！】水獺？海獺？還是河狸？ - 窩窩｜專注為動物發聲的獨立媒體
• 水獺河狸傻傻分不清？動物園分享辨識秘訣 What's Difference Between Otters & Beavers? - YouTube
• 有趣的動物（二） - 跟著鄭大師玩科學