RSPB
Print page

Turtle dove solution trialling and Trichomonas PhD

Turtle dove preening

Image: Trebol-a

The turtle dove is Britain’s only migratory dove, and populations have been declining since the 1970s (BTO; EBCC). This decline appears to have accelerated during recent years, and is also associated with range contractions (BTO).  Whilst problems on wintering grounds and hunting on migration may contribute to the population declines, the observed reduction in number of breeding attempts per year suggests that reduced productivity alone would lead to population decline (Browne & Aebischer, 2004).  This reduction in the number of nesting attempts has been associated with a reduction in available weed seeds on farmland and a dietary switch from weed seeds to cereals over the same time period.  This project aims to determine whether the provision of seed plots on farmland could increase the breeding success of turtle doves. Research from this project also highlighted a high prevalence of infection in turtle doves by the protozoan parasite Trichomonas gallinae (Lennon et al 2013), and a PhD project began in April 2013 investigates the potential role of parasites in the ecology of this species

Project objectives

  • Determine whether turtle doves are disappearing from certain habitats or geographic areas
  • Monitor nesting productivity and foraging habitat selection of turtle doves on farmland
  • Trial and evaluate conservation management options aimed at increasing breeding productivity by providing a source of seed food in farmland
  • Determine effects of trial management options on foraging behaviour and breeding productivity
  • Examine the prevalence and diversity of parasites infecting turtle doves on breeding and wintering grounds
  • Assess the impacts of infection by the Trichomonas gallinae on adult and nestling behaviour and survival
  • Investigate presence of Trichomonas in the environment

Key dates so far

  • Survey work currently underway
  • Solutions to provide seed-rich habitat are being tested on six farms across East Anglia
  • Fieldwork investigating the effects of seed-rich habitat on breeding success, survival & health of turtle dove is underway. Fieldwork is due for completion in September 2014
  • PhD on effects of disease started spring 2013, with fieldwork ongoing until autumn 2015

Work planned or underway

The fieldwork period for this project is May – Sept, 2010 – 2014.  Fieldwork takes place across East Anglia. 

2010: survey work to establish changes in turtle dove distribution since 2008 by surveying grid squares where turtle doves have previously been recorded.  Locating suitable sites for further work; including establishment of farms with plentiful seed trial plots (and controls); radiotracking turtle doves to locate nests and foraging locations; monitoring breeding productivity.

2011 & 2012: monitoring success of trial plots in terms of seed provision and establishment; monitoring their use by turtle doves, and the foraging site selection of turtle doves where seed plots are available compared to site selection where no additional seed plots are present; comparing chick provisioning behaviour and breeding productivity of turtle doves near trial plots to those without trial plots

2013 & 2014: monitoring breeding success, foraging and ranging behaviour of turtle doves on farms with and without trial seed plots; continuing to assess disease prevalence and experimentally testing the impacts of parasite infection through medication experiments.

Results

Squares with turtle dove territories declined by 34% over a two-year period.

Established scrub and hedgerows over 4 m tall positively influenced turtle dove presence and abundance, as did standing water.

Bare ground and fallow had positive effects on turtle dove abundance whereas grazed land negatively impacted abundance.

The positive effects of area of established scrub and volume of large hedgerows are likely to represent a declining density of birds selecting the best quality nest sites. We suggest that foraging habitat may be limiting distribution.

Solutions to provide seed-rich habitat are being tested. Mixes of flowers that provide suitable seed food and structure have been identified.

Bespoke habitat management for turtle doves will be rolled out in HLS from 2013.

Trichomonas parasite infection has been found in a high proportion of breeding turtle doves, and a PhD to investigate the impacts of parasite infection in turtle doves began in April 2013 in collaboration with the University of Leeds

Trichomonas infection prevalence in breeding turtle doves has been found to be ~96% (n=104 to date). Molecular analysis has identified another new strain of Trichomonas bringing the total number of strains identified within turtle doves to six.

Gallery

Who to contact

Dr Jenny Dunn
Conservation Scientist
E-mail: jenny.dunn@rspb.org.uk

Partners

Operation Turtle Dove

The University of Leeds

Funding

Natural England

Bird guide