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.
The European population is estimated at 3,640,000-8,000,000 pairs, which equates to 7,280,000-16,000,000 mature individuals (BirdLife International 2015). Therefore it is likely that the global population falls in the band 10,000,000-500,000,000 mature individuals. National population estimates include: c.10,000-100,000 breeding pairs and c.1,000-10,000 individuals on migration in China; c.100-10,000 breeding pairs and < c.50 wintering individuals in Japan, and c.10,000-100,000 breeding pairs and c.1,000-10,000 individuals on migration in Russia (Brazil 2009).
This species has undergone a small or statistically insignificant decrease over the last 40 years in North America (data from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven 2007). The European population trend is unknown (BirdLife International 2015).
The species nests colonially in newly eroded banks of rivers, streams, lakes, reservoirs and coastal cliffs (Tucker and Heath 1994, Turner 2004). Quarries are important nesting sites (Tucker and Heath 1994) and birds may use other man-made habitats including road and railway cuttings and building work excavations. Suitability of breeding sites depends on erosion which both creates new sites and destroys old ones (Turner 2004). Breeding occurs between late April and August usually with two clutches of between three and six eggs. Burrows are excavated by both male and female but male initiates the process. Erosion at breeding sites is vital for creating new nest sites which birds prefer. Sand martins may roost in reedbeds. They forage approximately 15 m above ground (Turner 2004) feeding mainly on insects but also taking spiders (Tucker and Heath 1994, Turner 2004). Important foraging habitats include water-bodies, grassland and farmland (Turner 2004). Urban and forested areas are less important. This species is migratory with Eurasian birds typically wintering in the Sahel zone and East Africa south to Mozambique (Tucker and Heath 1994). Breeding birds in North America migrate to South America (Turner 2004). Adult birds migrate soon after breeding. Juveniles roam over a wide area. Most adult birds return to the same breeding colony in subsequent years (Turner 2004).
Breeding sites are generally ephemeral and can often be lost through human activities (e.g. flood control, erosion control on rivers). In Europe, it is often dependent on artificial breeding sites such as quarries (Turner 2004), however quarry work can adversely affect breeding, though workers often take measures to prevent this. The use of pesticides causing declines in prey species, may impact the species (Tucker and Heath 1994). In the past droughts in wintering areas have caused severe large-scale population declines in western Europe (Tucker and Heath 1994, Turner 2004).
Conservation Actions Underway
Bern Convention Appendix II. In the U.K. the species is legally protected from disturbance during the working of quarries (Tucker and Heath 1994) and is included in several local Biodiversity Action Plans.
Conservation Actions Proposed
Due to the impermanent nature of breeding sites for the species the artificial sites should be created and old quarry sites should be acquired and protected in order to secure nesting areas. Flood alteration schemes should also be managed to provide breeding areas (Tucker and Heath 1994). Research should be undertaken in order to find out more on its distribution, habitats and behaviour during winter and on migration (Garrison 1999) as should monitoring of populations where possible. Reducing pesticide use is also likely to increase prey items for this species.
Text account compilers
Ashpole, J, Butchart, S., Ekstrom, J. & Khwaja, N.
BirdLife International (2018) Species factsheet: Riparia riparia. Downloaded from http://www.birdlife.org on 18/08/2018. Recommended citation for factsheets for more than one species: BirdLife International (2018) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 18/08/2018.