Gulls and terns – how do they differ?

Autor: Justyna Kubacka    

Many people confuse gulls and terns. Often, it is believed that gulls live by the sea and terns inland. This is not true. Both groups of these birds are associated with water, but one and the other can be found both by the sea and by fresh waters.

Gull and tern are names referring to entire groups birds related to each other. In Poland, there are many species.

There are a number of general characteristics that help the novice observer to distinguish gulls from terns. Terns are more slender and the shape of their bodies is more elongated than the gulls. Terns have short legs, their tails are forked and pointed at the tips. In flight birds of this group seem to be more agile and lighter than gulls. Terns feed on natural food: small fish, aquatic invertebrates and insects gathered over water plants. In contrast to gulls they do not eat refuse nor carrion.

Black-headed gull. Photo Marcin Łukawski

Black-headed gull. Photo Marcin Łukawski

Common tern. Photo Marcin Łukawski

Common tern. Photo Marcin Łukawski

Gulls are more massive than terns. They have more rounded shapes (heads, tails, wings, body) and longer legs. They can be found not only by the waters, but also away from them, such as feeding sites, the urban rubbish tips or on landfill sites, where they are happy to feed on food scraps. Some of the gulls spend winter in Poland, while all terns fly to warmer regions. If we find a bird in winter in Poland that we will consider is “a gull or a tern”, it will definitely be a gull. If we see such a bird foraging for food at a rubbish dump, or flying over buildings, or even sitting on roofs, we can be sure that this is a gull.

The project ‘Protecting the habitats of priority bird species of the Vistula Valley under conditions of intensive pressure of the Warsaw agglomeration’ (wislawarszawska.pl) has received a grant from the Financial Instrument for the Environment (LIFE+) and from the National Fund for Environmental Protection and Water Management.