How tracking one turtle dove could help save its whole species
By Jamie Wyver, Wed, 05/08/2015 – 08:38
In a first for UK science, a European Turtle dove (Streptopelia turtur) has been tracked by satellite tagging as it travelled 11,200km from Suffolk in England to Mali, Africa, and back again.
Flying mostly under the cover of darkness, the bird, named Titan, flew 500-700 kilometres a night across epic landscapes such as the Atlas Mountains of North Africa, Sahara Desert and the Gulf of Cádiz, visiting Senegal, Morocco and Spain en route. His maximum speed was 60km per hour.
Titan was fitted with a small, lightweight satellite tag in Suffolk in summer 2014 by the RSPB Centre for Conservation Science. Since then, Titan is playing a vital role in solving a serious conservation problem: how to prevent the rapid loss of his species from across Europe.
Turtle doves have recently been up listed to ‘Vulnerable’ status on the 2015 European red list, with their population plummeting by 77% across the continent since 1980. In fact, the disappearance of these birds is happening so rapidly that their numbers in the UK are halving every six years. If the decline continues at this rate, the species may be lost as a breeding bird in the UK within the next couple of decades.
In the UK, the number of breeding attempts per turtle dove pair halved between the 1960s and the late 1990s, which on its own can explain the population decline of UK breeding turtle doves. The RSPB is working on the premise that due to changes in agricultural practices, the availability of favoured weed seeds has declined, leading to reduced annual productivity. We are working with farmers to make the most of agri-environment schemes that support provision of hedges and scrub for nesting, and turtle-dove foraging plots: areas sown and managed specifically for the birds.
After being fitted with the tag, Titan remained in Suffolk until the end of September, when he headed through France into Spain and finally into Africa, going from Mauritania to Senegal and settling in Mali, where he spent the winter.
On migration, many turtle doves fly over the Mediterranean, a danger zone because of the hunting of turtle doves here. When Titan first entered this region, the legal hunting seasons in France and Spain were in full swing. Estimates suggest that around one million birds are killed across the western European flyway each autumn.
But this is only one of many challenges migratory birds face, and not all make it. RSPB researchers fitted two turtle doves with satellite tags in 2014. However, only Titan made it successfully to the wintering grounds in Africa and back again.
There are many factors in Africa that could play a part in the alarming decline of turtle doves as well, such as a lack of reliable sources of food and water and limited suitable roosting sites. Africa has seen significant agricultural expansion and intensification, as well as desertification, in recent decades.
Tracking Titan on his journey has given the RSPB Centre for Conservation Science valuable information, including the route taken, resting points and lengths of stays at those points, which will help understand where to target conservation efforts.
To encourage international collaboration on a plan to save turtle doves, the RSPB helped organise a symposium and round table event at the European Ornithologists Union conference this August to bring together academics and conservationists from across the species’ range at a flyway scale. Add to that, BirdLife International launched a new three-year EU LIFE+ funded project in April 2015 to identify the conservation needs of turtle doves (along with another 15 species) and to develop an International Species Action Plan.
There are also widespread efforts to ‘regreen’ the Sahel belt where turtle doves overwinter, which may bring back some of the roosting sites they need.
Titan finally left Mali on 19 May, and made swift progress through Mauritania and Algeria, arriving in Morocco on 24 May. Having just crossed the 2,000 km of the Sahara, he spent about two weeks resting in Morocco before crossing into Europe on 6 June. Passing through Spain and France, he finally returned to the UK, ending his journey very close to the spot he was first tagged a year earlier.
Breeding biology of sympatric Laughing (Streptopelia senegalensis) and Turtle (Streptopelia turtur) Doves in NE Algeria: here.
Determinants of nesting success in Turtle doves (Streptopelia turtur) in a North-African agricultural area. Determining the effects of environmental factors on nesting success of migrant and breeding game birds is paramount especially in man-made environments. Using Poisson regression, we investigated the influence on the number of chicks fledged per nest (N = 207) of nest placement, proximity of cereal crops and water sources, taking into account possible phenological and spatial differences between the five studied orchards. The best model, selected by Akaike criterion, shows positive linear effects of distance from the nest to the trunk, to closest cereal crops and a quadratic effect of nest height (with an optimum at 1.6m). In Guelma’s orange groves, nest placement and proximity to cereal crops have a direct impact on the productivity of Turtle doves. Further researches on other tree species (fruit and forest ones) are necessary to: (i) assess their importance for breeding Turtle doves and (ii) determine the effect of environmental variables on the maintenance of the species: here.
Studies of niche partitioning among Columbidae species have mainly addressed food habits and foraging activities, while partitioning in relation to nest-niche differentiation has been little studied. The recent expansion of Laughing dove Streptopelia senegalensis distribution throughout Morocco has raised concerns regarding its effects on native species, particularly Turtle doves S. turtur. The study, conducted in May 2008 and 2009, attempted to determine the factors that may play a role in nest-niche differentiation among the two sympatric dove species in the Tadla’s agricultural area (central Morocco). I used Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) to test the relevance of nest placement and human presence variables in the nest distribution of the two species. The results show substantial niche segregation in the olive nest-trees selected by Turtle and Laughing doves, with selection depending primarily on human presence and, to a lesser extent, the vertical distribution of nests. Observed nest-niche partitioning may diminish the potential for competition between these species and enhance opportunities for their coexistence. I further suggest guidelines for future studies that seek to understand the spatio-temporal dynamics of Laughing and Turtle dove coexistence in the region: here.