Common tern

Sterna hirundo

Key facts

Gaelic name: Steàrnag
Length: 31 – 35cm | Wingspan: 77 – 98cm | Weight: 90 – 150g
When in the UK: May – September
UK Conservation status: Red
Species on the Edge areas: East Coast; Solway

Species information

How to identify

The common tern is a medium-sized tern. It is slightly larger than the Arctic tern but very similar in appearance. Common terns and Arctic terns can be very difficult to tell apart. The common tern is whiter below, has shorter tail streamers, and has a longer bill, which is orangey-red with a black tip. It is silvery-grey above, with a black cap and short, red legs.

Migration

Common Terns arrive in the UK from the middle of April, departing again in late summer for wintering grounds that stretch south from the coast of Spain and around Africa’s western seaboard.

Distribution

Breeding common terns are widespread and primarily coastal in Scotland and are found on the lochs and islands of the west coast, Outer Hebrides, Northern Isles and around the inner Moray Firth. This contrasts with England, where the species’ range is dominated by inland colonies. In Ireland, colonies are more clustered, both on the coast and inland where most nest on islands in the largest lakes.

Common tern distribution map. Credit: RSPB www.rspb.org.uk/birds-and-wildlife/common-tern

Habitat and feeding

Common terns breed inland and on shingle and sandy beaches or rocky seashores. It feeds in lochs, rivers, reservoirs and inshore waters, mainly on fish namely sprats, herring, and sandeels.

Conservation status

UK Conservation Status: Amber

Threats

Food shortages – Overfishing of small fish is one cause, but long-tern climate change resulting in changes of fish stocks is also a hazard.
Disturbance – As once remote beaches are becoming more popular with walkers and dogs this can lead to increased disturbance.
Predation – Predation can be a problem at some sites, in particular non-native mink but also foxes, otters, and gulls.

What Species on the Edge is doing

All tern species have declined in Scotland and targeted action is needed to ensure Scotland’s coasts and islands continue to provide safe breeding zones for our visiting terns. Here at Species on the Edge, we are taking action for common terns in two of our project areas: the East Coast and the Solway Coast. Activity in these areas includes:

Creating new breeding sites
Enhancing established sites through effective habitat management
Protecting tern colonies from disturbance using signage and fencing
Engaging with local communities to increase awareness of terns and the threats they face and inspire community-led conservation action

Our work for terns

A panel from a tapestry of the east coast's most endangered species — Stitching for species on the East Coast

Species on the Edge has been delighted to work with the ‘Sutherland Stitchers’ to create a tapestry depicting eight species on the edge found on the east coast.

A model little tern in sand on a beach — Terning the Tide

Species on the Edge ‘Terning the Tide’ Project Manager, Robyn, tells us about the work being done across Scotland to secure a future for terns on our shores.

A painted model tern — Creating 3D-printed terns to signal safe breeding sites

Species on the Edge, the University of the Highlands and Islands Outer Hebrides and RSPB Scotland have been collaborating to produce 3D-printed terns to signal safe breeding sites to returning terns.

Resources

Common tern | RSPB

If you are interested in learning more about common terns, or are interested in getting involved in their conservation, get in touch with your local Species on the Edge team.