Editing Barn swallow (section)

=== Feeding ===
[[File:Swallow August 2013-2.jpg|thumb|Chicks in the nest|alt=Three chicks in a nest with their beaks open.]]

The barn swallow is similar in its habits to other aerial [[insectivore]]s, including other swallow species and the unrelated [[Swift (bird)|swift]]s. It is not a particularly fast flier, with a speed estimated at {{convert|11|m/s|km/h|abbr=on}}, up to {{convert|20|m/s|km/h|abbr=on}} and a wing beat rate of approximately 5, up to 7–9 times each second.<ref name= flight>{{cite journal|last= Liechti|first= Felix|author2= Bruderer, Lukas|date= 15 August 2002|url= http://jeb.biologists.org/cgi/reprint/205/16/2461|title= Wingbeat frequency of barn swallows and house martins: a comparison between free flight and wind tunnel experiments|journal= The Journal of Experimental Biology|volume= 205|issue= 16|pages= 2461–2467|doi= 10.1242/jeb.205.16.2461|pmid= 12124369|access-date= 21 May 2009|archive-date= 15 August 2009|archive-url= https://web.archive.org/web/20090815022433/http://jeb.biologists.org/cgi/reprint/205/16/2461|url-status= live}}</ref><ref name= Park>{{cite journal |last=Park |first=Kirsty |author2=Rosén, Mikael|author3= Hedenström, Anders |year= 2001|title=Kinematics of the barn swallow (''Hirundo rustica'') over a wide range of speeds in a wind tunnel |journal=The Journal of Experimental Biology |volume=204 |issue=15 |pages=2741–2750 |doi=10.1242/jeb.204.15.2741 |url=http://jeb.biologists.org/cgi/content/full/204/15/2741|pmid=11533124 |hdl=1893/306 |issn=0022-0949| archive-url= https://web.archive.org/web/20071109084723/http://jeb.biologists.org/cgi/content/full/204/15/2741| archive-date= 9 November 2007 | url-status= live|hdl-access=free }}</ref>

The barn swallow typically feeds in open areas<ref>{{cite book|author=Angela Turner|title=The Barn Swallow|url=https://books.google.com/books?id=bpfGYOqRDW0C&pg=PA41|date=29 January 2010|publisher=Bloomsbury Publishing|isbn=978-1-4081-2821-3|page=41|access-date=14 July 2017|archive-date=26 July 2020|archive-url=https://web.archive.org/web/20200726150505/https://books.google.com/books?id=bpfGYOqRDW0C&pg=PA41|url-status=live}}</ref> {{convert|7|–|8|m|ft|abbr=on}} above shallow water or the ground often following animals, humans or farm machinery to catch disturbed insects, but it will occasionally pick prey items from the water surface, walls and plants.<ref name=BWP/> Swallows have been observed feeding on insects that fly around active [[white stork]] nests as well.<ref>{{Cite journal |last1=Tryjanowski |first1=Piotr |last2=Jankowiak |first2=Łukasz |last3=Myczko |first3=Łukasz |last4=Mikula |first4=Peter |last5=Łuczak |first5=Andrzej |date=2024-01-25 |title=White stork Ciconia ciconia nests as an attractant to birds and bats |journal=Journal of Ornithology |volume=165 |issue=2 |pages=551–555 |language=en |doi=10.1007/s10336-023-02143-y |issn=2193-7192|doi-access=free |bibcode=2024JOrni.165..551T }}</ref> In the breeding areas, large [[fly|flies]] make up around 70% of the diet, with [[aphid]]s also a significant component. However, in Europe, the barn swallow consumes fewer aphids than the [[Common house martin|house]] or [[sand martin]]s.<ref name=BWP/> On the wintering grounds, [[Hymenoptera]], especially flying [[ant]]s, are important food items.<ref name=Turner/> [[Grasshopper]]s, [[Cricket (insect)|cricket]]s, [[dragonflies]], [[beetle]]s and [[moth]]s are also preyed upon.<ref>{{cite web | url=https://animaldiversity.org/accounts/Hirundo_rustica/ | title=Hirundo rustica (Barn swallow) | website=[[Animal Diversity Web]] }}</ref> When egg-laying, barn swallows hunt in pairs, but otherwise will form often [[Group size measures|large flocks]].<ref name=Turner/>

The amount of food a clutch will get depends on the size of the clutch, with larger clutches getting more food on average. The timing of a clutch also determines the food given; later broods get food that is smaller in size compared to earlier broods. This is because larger insects are too far away from the nest to be profitable in terms of energy expenditure.<ref name="Waugh1978">{{cite thesis|type=PhD|last=Waugh|first=David R.|date=1978|title=Predation strategies in aerial feeding birds|publisher=University of Stirling}}</ref>

[[Isotope]] studies have shown that wintering populations may utilise different feeding habitats, with British breeders feeding mostly over grassland, whereas Swiss birds utilised woodland more.<ref name= Evans>{{cite journal|last= Evans|first= K. L. |author2= Wadron, S.|author3= Bradbury, R. B. |year= 2003|title= Segregation in the African wintering grounds of English and Swiss Barn Swallows ''Hirundo rustica'': a stable isotope study |journal= Bird Study|volume= 50|issue= 3|pages= 294–299|doi= 10.1080/00063650309461322 |s2cid= 82263008 |doi-access= free}}</ref> Another study showed that a single population breeding in [[Denmark]] actually wintered in two separate areas.<ref name= Mollerhobson>{{cite journal|year= 2004|title= Heterogeneity in stable isotope profiles predicts coexistence of populations of barn swallows ''Hirundo rustica'' differing in morphology and reproductive performance |journal= Proceedings of the Royal Society of London. Series B: Biological Sciences|volume= 271|issue= 1546|pages= 1355–1362 | doi = 10.1098/rspb.2003.2565|pmid= 15306333|last1= Møller|first1= AP|last2= Hobson|first2= K A|issn= 0962-8452|pmc= 1691733}}</ref>

The barn swallow drinks by skimming low over lakes or rivers and scooping up water with its open mouth.<ref name = umich/> This bird bathes in a similar fashion, dipping into the water for an instant while in flight.<ref name= burton>{{cite book |last = Burton |first = Robert |title = Bird behaviour |year = 1985 |location = London |publisher = Granada |isbn = 978-0-246-12440-1 |url-access = registration |url = https://archive.org/details/birdbehaviour0000burt }}</ref>

Swallows gather in communal roosts after breeding, sometimes thousands strong. Reed beds are regularly favoured, with the birds swirling ''en masse'' before swooping low over the reeds.<ref name= Mullarney >{{cite book |last = Mullarney |first = Killian |author2= Svensson, Lars|author3= Zetterstrom, Dan|author4= Grant, Peter |title = Collins Bird Guide |year = 1999 |location=London |publisher = HarperCollins |isbn = 978-0-00-219728-1}} p242</ref> Reed beds are an important source of food prior to and whilst on migration; although the barn swallow is a diurnal migrant that can feed on the wing whilst it travels low over ground or water, the reed beds enable fat deposits to be established or replenished.<ref name=Euring>{{cite web|last=Pilastro |first=Andrea |title=The EURING Swallow Project in Italy |url=http://www.euring.org/about_euring/newsletter2/euring_swallows_italy.htm |date=December 1998 |work=Euring Newsletter, Volume 2 |access-date=1 December 2007 |archive-url=https://web.archive.org/web/20071203210458/http://www.euring.org/about_euring/newsletter2/euring_swallows_italy.htm |archive-date=3 December 2007 |url-status=dead }}</ref>