Red-throated Diver

Listen to example recordings of the main vocalisations of Red-throated Diver, provided by xeno-canto contributors.

This species can be found on the following statutory and conservation listings and schedules.

UK Birds of Conservation Concern	Green listed
Species of European Conservation Concern	Least Concern
IUCN Red List of Threatened Species (global)	Least Concern
Schedule 1 license required (to disturb)	Yes
Birds Directive Annex 1	Yes
Listed on the Annexes of	WCA(I), WBD(I), Bern(II), Bonn(II), AEWA

Breeding numbers are quite variable between years and not monitored annually by the BTO; trends are hard to assess except by intensive survey. There was a full UK survey in 1994 (935 pairs; Gibbons et al. 1997) and a repeat in 2006, by when the estimated UK breeding population had increased significantly by 34%, with stability in Shetland and Orkney but increase across the Hebrides and Scottish mainland (Dillon et al. 2009). Complete surveys of Shetland indicated a decrease of 36% there between 1983 and 1994 (Gomersall et al. 1984, Gibbons et al. 1997) and there was minor further decrease there by 2006 (Smith et al. 2009). The full surveys indicate that Shetland held 46% of the national total of breeding pairs in 1994 and 33% in 2006, though this decrease reflects the significant increases elsewhere in Scotland rather than the small decline in Shetland (Smith et al. 2009). JNCC's Seabird Monitoring Programme shows that breeding numbers at sample study areas in Shetland fluctuated without long-term change during 1980-2005, with low points in 1980, 2000 and 2004 (Mavor et al. 2008). Though previously amber listed through its 'depleted' status in Europe, the species was moved to the UK green list in 2015 (Eaton et al. 2015). Wintering numbers, mostly of birds from northern Europe, peaked in 2011/12 but have since decreased and are now similar to numbers in the early 1990s (WeBS: Frost et al. 2020).

Since the 1980s, there may have been some tendency for more pairs to hatch a second chick, although two-chick broods are only occasional in Orkney and changes in the distribution of nests recorded might have influenced the results. In 2011, however, there were fewer two-chick broods in Shetland than in any year since at least 1979 (Holling et al. 2013).

Wintering Red-throated Divers are recorded all round the coast of Britain & Ireland, plus at a scatter of inland sites, mainly in northern and eastern England. The highest concentrations are along North Sea coasts, southwest Scotland and southwest Ireland. Breeding birds are restricted to freshwater lochs and bogs in Co. Donegal in Ireland and in north and west Scotland.

Red-throated Diver winter range has expanded by 32% since the 1981–84 Winter Atlas, with a large part of this being off northwest Scotland and parts of western Ireland. Some of this increase may be due to better coverage but some gains are likely to be real.

Red-throated Divers are recorded year-round

View a summary of recoveries in the Online Ringing Report.

Foreign locations of birds ringed or recovered in Britain & Ireland

View number ringed each year in the Online Ringing Report

Maximum Age from Ringing	35 years 11 months 23 days (set in 2018)
Typical Lifespan	9 years with breeding typically at 3 year
Adult Survival	0.84
Juvenile Survival	0.37 (to age 2)

Wing Length

Adults

289.9±9.7 | Range 279–304mm, N=21

Body Weight

Adults

1.68±0.21 | Range 1.43–2.03kg, N=20

Feather measurements and photos on featherbase

Ring size	K*
Field Codes	2-letter: RH | 5-letter code: RETDI | Euring: 20

For information in another language (where available) click on a linked name

Causes of change

There is little good evidence available regarding the drivers of the breeding population change in this species in the UK.

Further information on causes of change

No further information is available.

Information about conservation actions

The main drivers of change are not known for these species. However, because food for chicks is obtained largely from the sea close to breeding lochs, a reliable supply of suitable marine prey nearby is a requirement for successful breeding. Shortages of sand eels have recently been a major factor in depressing breeding success in Shetland (Forrester et al. 2007). Divers are thus vulnerable to losses of feeding grounds and to decreases in fish stocks and hence policies which protect marine areas adjacent to breeding areas would be prudent until the reasons for the decline have been confirmed.

Outside the breeding season, this species is believed to be among the most sensitive to offshore wind farms, and in particular at risk of displacement from wind farms (Furness et al. 2013; Wade et al. 2016; Heinanen et al. 2020), and therefore winter distribution should be taken into account when making decisions about wind farm developments, to protect both British and European breeding birds.