Difference between a Duck and Goose

Identifying the differences between a duck and a goose may not be as immediately obvious as it first seems. Most people would think that they wouldn’t get confused between the wildfowl but in their natural environment it is perfectly possible to mistake a goose for a duck.

Most people would probably say that the most obvious difference between a duck and a goose is that a goose is bigger than a duck. In most cases this is true but a Brent goose, which is one of the smaller members of the goose, could be the same size as a large duck.

Canada Goose and Wood Duck families - Jonathon Jongsma - CC-BY-SA-2.0

Looking at the science behind the two birds there is actually little difference between a duck and a goose. Both are members of the Kingdom Animalia; Phylum Chordata; Class Aves; Order Anseriformes; and Family Anatidae. Indeed it is only the subfamily that differs, just as swans differ from geese and ducks.

There are some physical characteristics that are different between a duck and a goose, although there are exceptions to this, and any generalisation made about the two birds. A goose has a longer neck than a duck, although ducks have relatively long necks themselves compared to many other birds.
Colour is also used as a differential between ducks and geese. Geese tend to be grey or white, with no difference in colours and markings between the male and female geese. Ducks though are often multicoloured with differences in colours between male and female members of the same type of duck.

Diets also tend to differ between the two birds, with ducks eating fish and insects, and geese having an herbivorous diet comprising of grain and grasses. This diet also sees the two birds locating in different areas, with geese grazing on land, and ducks feeding on and under the water.
There are also other differences between a duck and a goose that sometimes are true, with geese migrating further than ducks, and also having more webbing on their feet.

Toulouse goose and domestic duck - Jim Linwood - CC-BY-2.0

The differences between a duck and a goose are further complicated by the group of birds that is often placed between the two, the Shelducks. These are another part of the Anatidae family, many of who are called geese without actually being true members of the geese group of birds. Shelducks are often larger than normal ducks, and spend their lives split between time on the water and time on the land.

The difference between a duck and a goose is tiny, and is best described as being colour differences and the length of the neck. The two birds though can be confused and from a distance especially is an easy thing to do.

Copyright - First Published 4th March 2010