LC
Corn Bunting Emberiza calandra



Justification

Justification of Red List category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population justification
In Europe, the breeding population is estimated to number 18,300,000-31,300,000 pairs, which equates to 36,700,000-62,600,000 mature individuals (BirdLife International 2015). Europe forms c.20% of the global range, so a very preliminary estimate of the global population size is 183,500,000-313,000,000 mature individuals, although further validation of this estimate is needed.

Trend justification
The population is declining markedly in north-west mainland Europe and less dramatically in central Europe owing to changing agricultural practices and climate change (Byers et al. 1995). In Europe, trends between 1980 and 2013 show that populations have undergone a moderate decline (p<0.05) (EBCC 2015). There is no indication of a decline in the central Asian population however information is sparse (Madge and de Juana 2017).

Ecology

The species inhabits open rolling grasslands, both in natural steppe and in agricultural land. It tolerates scattered bushes, but avoids extensive bushy cover (Madge and de Juana 2017). In the northern part of its European range it is confined mainly to cereal fields and hay meadows. In southern Europe it has a broader habitat array occupying several types of open country, including grasslands and steppes. During winter it gathers in flocks and may show rather short distance displacements to favourable feeding grounds, often fallow or stubble fields (Hagemeijer and Blair 1997, Bos and van Noorden 2010, Madge and de Juana 2017). The breeding season starts relatively late, from late May onward in north-western populations, but probably earlier in southern populations. The nest is placed on the ground, hidden among vegetation. It is entirely built by the female. The clutch, usually four to six eggs, is incubated by the female alone. The incubation period is 12–14 days. The chicks are fed by the female (with the male in attendance) and leave the nest after 9–13 often before being able to fly (Madge and de Juana 2017). The species's diet consists mainly of plant seeds, but during the breeding season it includes a high percentage of invertebrates, primarily small insects. The species is mainly sedentary in the north and west of its range whilst central and eastern European populations are partially migratory. Central Asian birds move south (Madge and de Juana 2017).

Threats

The strong decline of the species in north-western Europe is mainly a consequence of agricultural intensification. Cropped areas of spring-sown cereals have decreased, mowing of hay has been advanced and the use of pesticides has increased. Winter food supplies have decreased as a consequence of the loss of spring tillage, increased pesticide usage and improved harvesting and storage techniques. The increase of winter-sown cereal cropland has affected the species adversely through increased nest losses, as a consequence of early harvesting and the early ploughing of winter cereal stubble fields (Donald and Forrest 1995, Hagemeijer and Blair 1997, Madge and de Juana 2017). The abolition of the European set-aside scheme is of great concern, not only for birds. Set-aside has provided valuable food and nesting sites for many farmland birds whose populations were declining due to agricultural intensification (BirdLife International 2008). The species may be vulnerable to climatic extremes along its northern range limits (Hagemeijer and Blair 1997, Madge and de Juana 2017).

Conservation actions

Conservation Actions Underway
The species is classified as Critically Endangered on the Dutch Red List (Hustings et al. 2004) and Vulnerable on the Swiss Red List (Keller 2010). The species is on the British list of Birds of Conservation Concern (Eaton et al. 2009).

Conservation Actions Proposed
Measures related to the restoration of the species's habitat in farmland should be taken and effectively carried out in agri-environment schemes/targeted management interventions. Specific measures include: increasing invertebrate availability by providing grassy margins or beetle banks and by selective spraying of headlands (Brickle et al. 2000); providing early summer and late summer nesting habitat close to each other to give the species the opportunity to rear two broods in a season; winter barley or late mown hay grown alongside weed-rich or undersown spring cereals would be a good combination; set-aside or similar agri-environment crop types should remain uncut and unsprayed during the breeding season and should preferably be offered close to song-posts, such as overhead wires (Perkins et al. 2012); the provision of unharvested, extensively managed cereal crops as an agri-environment option where intensively managed cereal crops are the main nesting habitat (Setchfield et al. 2012); delayed mowing (as part of agri-environment schemes) in areas where the species still breeds in meadows could significantly improve its breeding performance (Perkins et al. 2013); measures aimed at providing winter food habitat, including stubble fields with cereal seeds (Perkins et al. 2007, Perkins 2008, Bos and van Noorden 2010).

Acknowledgements

Text account compilers
Ashpole, J, Ekstrom, J., Butchart, S.


Recommended citation
BirdLife International (2024) Species factsheet: Corn Bunting Emberiza calandra. Downloaded from https://datazone.birdlife.org/species/factsheet/corn-bunting-emberiza-calandra on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/11/2024.