Song Thrush

From Rio to Sussex

 

Action

Species Statement for Sussex

Download the Song Thrush .PDF file
Introduction
Current status in Sussex
Factors affecting species
National SAP
Current Action
References
 
 
 
 
 

song thrush

Turdus philomelos

The National Species Action Plan as well as the Sussex Arable Land, Chalk Grassland, Hedgerows, Urban and Woodland Habitat Action Plans will be used to implement and monitor action for the song thrush in Sussex.

1. Introduction

This is a common and widespread species, which is declining throughout the UK. It is a partial migrant and also an abundant passage migrant, with large numbers of Continental breeders overwintering in the UK and with many birds, which breed in the UK, wintering further south in Europe. These birds are generally more abundant in the east than the west of the country.

The song thrush population is estimated at 1.1 million breeding pairs (The State of the UK's birds, 2001). Following the winter of 1962/63 the population declined, but recovered to a stable level within three to four years. The numbers subsequently remained stable until the mid 1970s, after which they declined steadily. RSPB research shows that, between 1972 and 1996, there was a 66% decline in song thrush numbers on farmland and 39% decline in woodland habitats.

The song thrush is protected under the EC Birds Directive, the Wildlife & Countryside Act 1981 and the Wildlife (Northern Ireland) Order 1985. It is a Red List species (high conservation concern) in Birds of Conservation Concern: 2002-2007.

2. Current Status in Sussex

Song thrush numbers have declined less in the south east of Britain than most other areas. In Sussex, the song thrush is an abundant resident across the county and partial migrant; abundant passage migrant and very common winter visitor.

Song thrush densities are highest in the Weald. They are relatively scarce breeders in open downland even where there is scrub. They have a similar distribution to mistle thrushes in Sussex. Song thrushes appear to perform reasonably well in urban/suburban areas, where there is a relatively low level of pesticide use and good availability of feeding and nesting sites - although the domestic cat is a serious predator.

In the mid 1970s, Shrubb (1979) considered that song thrush numbers were increasing. Since then, a steady national decline has been reflected in Sussex. Shrubb estimated an average of 24 pairs per km2 on Sussex farmland. Censuses in various habitats during the 1980s gave a combined average of less than 9 pairs per km2 . Assuming that these figures apply to the whole county, the Sussex breeding population can be estimated at 35,000 pairs. This is likely to fluctuate in response to mild or severe winters.

The percentage of Sussex breeding birds that emigrates for the winter is not known and may vary. Song thrushes from the continent pass through Sussex in autumn, particularly along the Downs and at the coast. Both route and destination are clearly shown by ringing recoveries: across the Channel, down the Atlantic coast of France and into western Spain and Portugal, where many are shot. Other migrants arrive in the autumn from the Low Countries, Germany, Denmark and maybe Norway.
Song thrushes are badly affected by severe weather, as in early 1985, when they were seen flying west at the rate of 200 an hour at Saltdean on 7th January. (SOS 1996).

3. Current Factors Causing Loss or Decline [top]

The species is covered in the Sussex Arable Land Habitat Action Plan as it has suffered greatest decline in agricultural areas.
Reasons for the decline in song thrush numbers are poorly understood, but may relate to the following factors:
· Changes in farming affecting food supply and the availability of nest sites, particularly the switch from spring to autumn sowing of cereals and possibly increased use of pesticides.
· Severe winter weather and dry soil conditions in late summer affect food supply. Not enough young are raised to offset normal winter mortality, resulting in rapid population decline.
· Song thrush prey inhabit damp grassland, ditches, scrub and woodland. The loss of key feeding habitats and the consequent reduction in the availability of invertebrates, is probably the main reason why these birds are failing to raise enough broods each year. Woodland and grazed grassland in the preferred habitat. Cereal land is avoided.
· Predation by corvids and foxes.
· Song thrushes are a favourite prey of sparrowhawks. The resurgence of this predator in Sussex since the 1960s cannot have helped.
· Competition with blackbirds.
· Hunting in southern Europe.

Standing Fresh Water HAP

4. National Species Action Plan[top]

National Species Action Plan objectives and targets are as follows:
· Halt the decline in numbers of song thrush in the UK by the year 2000 (revised in 2001 review).
· Maintain the UK geographical range of the song thrush at the 1995 level as measured by the frequency of occupation of BBS squares.
· Maintain the UK population size of the song thrush at or above the 1995 level as measured by the BBS index.
· By 2010, increase the geographical range at least to the 1968/72 range.
· By 2010, increase the population size at least to the 1970 level as measured by the CBC/BBS index.

Proposed actions include:
· Ensure that the results of ongoing research on the causes of decline are taken into account in agriculture schemes, woodland schemes and policy.
· Promote the uptake of sensitive farming options under existing incentive schemes to benefit song thrush.
· Consider persuading the European Commission to ban or discourage hunting in France.
· Advisory, research and monitoring activities. These to be disseminated to all partners.


5. Current Action[top]

Little action was taken for the species until British Trust for Ornithology (BTO) census work highlighted its decline. Recent RSPB work has included surveys, research on the species' ecology and investigation of the causes of the decline (see references below). One of the survey areas was close to Graffham, near the South Downs in West Sussex. The national species action plan has been prepared by the RSPB, in collaboration with JNCC and the country agencies. Conservation actions could include increasing food-rich habitat and nesting cover areas (such as woodland, scrub, damp ditches and permanent grassland) in arable land.

References [top]

RSPB (2002) song thrush research, including survey of a 'stable population' at Graffham, West Sussex:
· Habitat utilisation by song thrushes on lowland farmland during summer and winter.
· Habitat selection by song thrushes in stable and declining farmland populations.
· Summer diet and body condition of song thrushes in stable and declining farmland populations

Sussex Ornithological Society. (1996) Birds of Sussex ed. Paul James
Shrubb (1979) The Birds of Sussex - their present status
The State of the UK's Birds (2000 & 2001)





Standing Fresh Water HAP

 

 


Standing Fresh Water HAP