河狸（学名：Castor fiber），是河狸科、河狸属的动物。河狸躯体肥大，雌、雄无明显差异，头短钝，眼小，颈短，四肢短宽，前肢短，足小、具强爪，后肢粗壮有力，尾大、扁平。

The beaver (scientific name: Castor fiber) is an animal of the genus Castor or family. The beaver has a large body, no obvious difference between female and male, short and blunt head, small eyes, short neck, short and wide limbs, short forelimbs, small feet with strong claws, strong and powerful hind limbs, and large and flat tail.

生活营

河狸夜间活动，白天很少出洞，善游泳和潜水，不冬眠，自卫能力很弱，胆小，喜食多种植物的嫩枝、树皮、树根，每年繁殖1次，每胎1-6仔，栖息于寒温带和亚寒带森林河流沿岸，主要分布于欧洲，其他地区数量较少。

Beavers are active at night, rarely out of the hole during the day, good at swimming and diving, do not hibernate, self-defense ability is very weak, timid, like to eat a variety of plant shoots, bark, roots, reproduce once a year, 1-6 children per litter, inhabits in the cold temperate zone and subfrigid zone forest along the river, mainly distributed in Europe, other regions less.

河狸一般在近水处筑巢，巢室用枝条和泥土搭成，离地面高0.8-1.9m。河狸栖居方式大体有洞居、巢居和洞巢居结合体3类。洞居有永久性和临时性两种。每年春泛期，由于冰雪融化，河水泛滥，部分河狸洞系被洪水淹没，迫使这些河狸进行短距离迁移，在支渠或小岛上修筑简单的洞穴，供临时或避难用。永久性的洞穴是河狸越冬、繁殖的场所，结构比较复杂。洞系一般分布在河岸较高（距冰面1.5m以上）地段；洞巢结合体（即地下有洞系，地面上添加一个土木结构的巢）多分布在河岸距冰面高度1.5m以下的中型河岸上。单纯的巢，则筑在沼泽中或浅水地的岛上。这些洞系和洞巢多处于水流平缓，水深一般在2m以上，河宽15m左右的河弯地段。

Beavers generally nest near the water, and the nest room is made of branches and soil, which is 0.8-1.9m high from the ground. There are three types of living patterns of beavers: cave dwelling, nest dwelling and cave nest combination. Caves can be either permanent or temporary. Every year during the spring flood, due to the melting of snow and ice, the river is flooded, and some of the beaver cave system is flooded, forcing these beavers to move short distances and build simple caves in branch canals or islands for temporary or refuge. The permanent cave is a place for the beaver to overwinter and breed, and its structure is more complex. The cave system is generally distributed in the higher part of the river bank (above 1.5m from the ice surface). Cavity and nest combinations (i.e. nests with holes in the ground and a civil structure added to the ground) are mostly distributed on medium banks with a height of 1.5m from the ice surface. A simple nest is built in a marsh or on an island in shallow water. These cave systems and cave nests are mostly in the gentle water flow, the water depth is generally more than 2m, and the river width is about 15m

分布营

分布于：白俄罗斯、中国、法国、德国、哈萨克斯坦、卢森堡、蒙古、挪威、俄罗斯联邦；区域性灭绝：摩尔多瓦、葡萄牙、土耳其、英国；引入：奥地利、比利时、克罗地亚、捷克共和国、丹麦、爱沙尼亚、芬兰、匈牙利、意大利、拉脱维亚、列支敦士登、立陶宛、黑山、荷兰、波兰、罗马尼亚、塞尔维亚、斯洛伐克、斯洛文尼亚、西班牙、瑞典、瑞士、乌克兰；来源不确定：保加利亚，北美有阿拉斯加州。

在中国仅分布于新疆东北部的青河、布尔根河和乌伦古河等水体。

Distributed in: Belarus, China, France, Germany, Kazakhstan, Luxembourg, Mongolia, Norway, Russian Federation; Regional extinctions: Moldova, Portugal, Turkey, United Kingdom; Introduced in: Austria, Belgium, Croatia, Czech Republic, Denmark, Estonia, Finland, Hungary, Italy, Latvia, Liechtenstein, Lithuania, Montenegro, Netherlands, Poland, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Ukraine; Uncertain source: Bulgaria, Alaska in North America.

In China, it is only distributed in the Qinghe River, Burgen River and Ulungu River in the northeast of Xinjiang.