Editing Alpine chough (section)

===Breeding===
[[File:Alpendohle Ei-3c.jpg|thumb|alt= A cream egg with light buff blotches|Eggs vary from cream to [[buff (colour)|buff]] to light-green, and have brown speckles.<ref name= Madge94/>]]
The Alpine chough is socially [[monogamy in animals|monogamous]], showing high partner fidelity in summer and winter and from year to year.<ref name= delestradesty>{{cite journal | last= Delestrade | first= Anne|author2=Stoyanov, Georgi | year= 1995| title= Breeding biology and survival of the Alpine Chough ''Pyrrhocorax graculus'' | journal= Bird Study | volume=42 | pages=222–231 | doi =10.1080/00063659509477171 | issue= 3 | doi-access= free | bibcode= 1995BirdS..42..222D}}</ref> Nesting typically starts in early May, and is non-colonial, although in suitable habitat several pairs may nest in close proximity.<ref name= Madge94/> The bulky nests are composed of roots, sticks and plant stems lined with grass, fine twiglets or hair, and may be constructed on ledges, in a cave or similar fissure in a cliff face, or in an abandoned building. The [[clutch (eggs)|clutch]] is 3–5 glossy whitish eggs, averaging {{convert|33.9|x|24.9|mm|in}} in size,<ref name= Harrison>{{cite book| last = Harrison | first = Colin James Oliver | title = A field guide to the nests, eggs and nestlings of European birds: with North Africa and the Middle East | year =1975 | publisher = Collins | isbn = 978-0-00-219249-1 |page = 316}}</ref> which are tinged with buff, cream or light-green and marked with small brown blotches;<ref name = Madge94/> they are incubated by the female for 14–21 days before hatching.<ref name = BWP/> The chicks hatch with a dense covering of natal [[down feather|down]] — in contrast to those of the red-billed chough, which are almost naked<ref name=agd>{{cite book|title=Avian growth and development. Evolution within the altricial precocial spectrum. |author1=Starck, J Matthias |author2=Ricklefs, Robert E. |year=1948 |publisher=Oxford University Press |location=New York |isbn=978-0-19-510608-4 |page=7 |url=http://sci.bio.lmu.de/morpho/downloads/agd1.pdf |archive-url=https://wayback.archive-it.org/all/20081216211957/http://sci.bio.lmu.de/morpho/downloads/agd1.pdf |url-status=dead |archive-date=16 December 2008 }}</ref> — and [[fledge]] 29–31 days from hatching.<ref name = BWP/> The young birds are fed by both parents, and may also be fed by other adults when they have fledged and joined the flock.<ref name = Madge94/> Breeding is possible in the high mountains because chough eggs have fewer pores than those of lowland species, reducing loss of water by evaporation at the low atmospheric pressure.<ref>{{cite journal | last= Rahn | first=H. |author2=Ar, A. | s2cid=27372255 | year= 1974 | title= The avian egg: incubation time and water loss | journal= The Condor | volume=76 | issue = 2 | pages= 147–152| doi =10.2307/1366724 | jstor = 1366724 }}</ref> The [[embryo]]s of bird species that breed at high altitude also have [[haemoglobin]] with a genetically determined high affinity for oxygen.<ref>{{cite journal | last= Black | first= Craig Patrick |author2=Snyder, Gregory K | year= 1980 | title= Oxygen transport in the avian egg at high altitude | journal= American Zoologist | volume= 20 | issue =2 | pages= 461–468 | doi = 10.1093/icb/20.2.461 | doi-access= free }}</ref>

In the western Italian Alps, the Alpine chough nests in a greater variety of sites than red-billed chough, using natural cliffs, pot-holes and abandoned buildings, whereas the red-billed uses only natural cliffs (although it nests in old buildings elsewhere).<ref name=Madge94/><ref name= Rolando2/><ref name= Blanco5>{{cite journal|last= Blanco |first= Guillermo |author2= Fargallo, Juan A.|author3= Tella, José Luis Cuevas |author4= Jesús A. |date=February–March 1997 |title= Role of buildings as nest-sites in the range expansion and conservation of choughs ''Pyrrhocorax pyrrhocorax'' in Spain |journal=Biological Conservation |volume= 79 |issue=2–3 |pages=117–122 | doi=10.1016/S0006-3207(96)00118-8|bibcode= 1997BCons..79..117B |url=https://digital.csic.es/bitstream/10261/58104/1/Bc12.pdf |hdl= 10261/58104 |hdl-access= free }}</ref> The Alpine chough lays its eggs about one month later than its relative, although breeding success and reproductive behaviour are similar. The similarities between the two species presumably arose because of the same strong environmental constraints on breeding behaviour.<ref name= Rolando2/>

A study of three different European populations showed a mean clutch size of 3.6 eggs, producing 2.6 chicks, of which 1.9 fledged. Adult survival rate varied from 83 to 92%, with no significant difference detected between males and females. Survival of first-year birds was, at 77%, lower than that of adults. The availability or otherwise of human food supplied from tourist activities did not affect breeding success.<ref name= delestradesty/>