Sterna sandvicensis (Latham 1787),  Sandwich Tern (Lariidae)

Compiled by Christof Herrmann, Henrik Skov & Wlodzimierz Meissner

1. Description of the Habitat/Autecology of the species

Breeding: islands, typically within colonies of black-headed gulls (Larus ridibundus); very sensitive to the presence of predators; the breeding populations are fluctuating with respect to numbers and breeding sites.

2. Distribution, past and present

The Sandwich Tern is a widespread but very dispersed breeder in coastal areas of Europe, which holds >50 % of the global population. The European population amounts about 82,000-130,000 breeding pairs and underwent a moderate decline between 1970-1990. Because the population still remains below the level that preceded the decline, it is evaluated as depleted (BirdLife International, 2004). In the Baltic area, the species breeds in Germany, Poland, Estonia, Sweden and Denmark.

 (Data from: Hälterlein et al., 2000; BirdLife International, 2004)

3. Importance (Sub-regional, Baltic-wide, Global)

The Baltic Sea hosts a relatively small proportion (< 10 %) of the total European population.

4. Status of threat/decline

Long-term decline in the whole Baltic breeding area.

5. Threat/decline factors

The widespread declines are based on habitat deterioration due to recreational activities near breeding islands and increases in predators (foxes, mink, Grell, 1998; Hälterlein et al., 2000).

6. Options for improvements

Predator control and prohibition of access to breeding islands.

7. References

BirdLife International (2004): Birds in Europe. Population estimates, trends and conservation status. BirdLife Conservation series 12, Cambridge, UK. 374 pp.

Grell, M.B. (1998). Fuglenes Danmark. GAD, København.

Hälterlein, B., Südbeck, P., Knief, W. & Köppen, U. 2000. Brutbestandentwicklung der Küstenvögel an Nord- und Ostsee unter besondere Berücksichtigung der 1990er Jahre. Vogelwelt 121: 241-267.