Brånsjön is probably the most famous bird lake in Västerbotten, and is beautifully situated in the agricultural landscape of the Umeå river valley in Vännäs municipality. Brånsjön is a shallow and nutrient-rich lake, with a water depth ranging from just a few inches to a meter in the deepest places. Most of the lake is covered with water vegetation horsetail, sedges and marsh cinquefoil and the open water is rather limited.
Historically argued wetlands around the lake by mowing or grazing livestock, but this has long since ceased. Around the lake there are more or less narrow borders with beach forest, dominated by birch and willow thickets. Mainly east of the lake includes agricultural land in the protected area. At the outlet of the lake's east side is a pump station that serves to regulate the water level in the lake.
Brånsjön is an important nesting site for several species of birds, species like Horned Grebe, Red-necked Grebe, Whooper Swan, several species of ducks, little gull and the ortolan bunting. In the spring, you can often see large numbers of ducks, geese and waders rest on the fields around the lake, with numbers on eg up to 5000 ruffs at the same time. The number of geese is often large.
The area is a protected nature reserve and Natura 2000 area