Editing Bird nest (section)

==Nest protection and sanitation==

Many species of bird conceal their nests to protect them from predators. Some species may choose nest sites that are inaccessible or build the nest so as to deter predators.{{sfn|Rudolph|Kyle|Conner|1990}} Bird nests can also act as habitats for other [[inquiline]] species which may not affect the bird directly. Birds have also evolved nest sanitation measures to reduce the effects of parasites and pathogens on nestlings.

Some aquatic species such as [[grebe]]s are very careful when approaching and leaving the nest so as not to reveal the location. Some species will use leaves to cover up the nest prior to leaving.

Ground birds such as plovers may use ''broken wing'' or ''rodent run'' displays to distract predators from nests.<ref>{{harvnb|Byrktedal|1989}}</ref>

Many species attack predators or apparent predators near their nests. [[Kingbird]]s attack other birds that come too close. In North America, [[northern mockingbird]]s, [[blue jay]]s, and [[Arctic tern]]s can peck hard enough to draw blood.<ref>{{harvnb|Gill|1995}}</ref> In Australia, a bird attacking a person near its nest is said to ''swoop'' the person. The [[Australian magpie]] is particularly well known for this behavior.<ref>{{harvnb|Kaplan|2004}}</ref>

Nests can become home to many other organisms including parasites and pathogens.<ref>{{Citation |last=Hicks |first=Ellis A. |title=Checklist and bibliography on the occurrence of insects in birds' nests |year= 1959|publisher=Iowa State College Press, Ames| url=https://archive.org/details/checklistbibliog00hick}}</ref> The excreta of the fledglings also pose a problem. In most passerines, the adults actively dispose the [[fecal sac]]s of young at a distance or consume them. This is believed to help prevent ground predators from detecting nests.<ref>{{harvnb|Petit|Petit|Petit|1989}}</ref> Young birds of prey however usually void their excreta beyond the rims of their nests.<ref>{{harvnb|Rosenfeld|Rosenfeld|Gratson|1982}}</ref> [[calliphoridae|Blowflies]] of the genus ''[[Protocalliphora]]'' have specialized to become obligate nest parasites with the maggots feeding on the blood of nestlings.<ref>{{harvnb|Sabrosky|Bennett|Whitworth|1989}}</ref>

Some birds have been shown to choose aromatic green plant material for constructing nests that may have insecticidal properties,<ref>{{harvnb|Wimberger|1984}}</ref><ref>{{harvnb|Clark|Mason|1985}}</ref> while others may use materials such as carnivore scat to repel smaller predators.<ref>{{harvnb|Schuetz|2005}}</ref> Some urban birds, house sparrows and house finches in Mexico, have adopted the use of cigarette butts which contain nicotine and other toxic substances that repel ticks and other ectoparasites.<ref>{{Cite journal |last1=Suárez-Rodríguez |first1=Monserrat |last2=Garcia |first2=Constantino Macías |date=2017 |title=An experimental demonstration that house finches add cigarette butts in response to ectoparasites |url=https://onlinelibrary.wiley.com/doi/10.1111/jav.01324 |journal=Journal of Avian Biology |language=en |volume=48 |issue=10 |pages=1316–1321 |doi=10.1111/jav.01324 |issn=0908-8857|url-access=subscription }}</ref><ref>{{cite journal|doi=10.1098/rsbl.2012.0931|pmid=23221874|pmc=3565511|title=Incorporation of cigarette butts into nests reduces nest ectoparasite load in urban birds: New ingredients for an old recipe?|journal=Biology Letters|volume=9|issue=1|pages=20120931|year=2012|last1=Suarez-Rodriguez|first1=M.|last2=Lopez-Rull|first2=I.|last3=MacIas Garcia|first3=C.}}</ref>

Some birds use pieces of snake slough in their nests.<ref>{{Citation|last=Strecker|first=John K|year=1926|title=On the use, by birds, of snakes' sloughs as nesting material|journal=Auk|volume=53|pages=501–507|url=http://sora.unm.edu/sites/default/files/journals/auk/v043n04/p0501-p0507.pdf|doi=10.2307/4075138|issue=4|url-status=live|archive-url=https://web.archive.org/web/20131224084143/http://sora.unm.edu/sites/default/files/journals/auk/v043n04/p0501-p0507.pdf|archive-date=24 December 2013|jstor=4075138}}</ref> It has been suggested that these may deter some nest predators such as squirrels.<ref>{{Citation|first1=Elizabeth C.|last1=Medlin|first2=Thomas S.|last2=Risch|title=An experimental test of snake skin use to deter nest predation|journal=The Condor|year=2006|volume=108|issue=4|pages=963–965|doi=10.1650/0010-5422(2006)108[963:AETOSS]2.0.CO;2|s2cid=86039366 |url=https://zenodo.org/record/956844|doi-access=free}}</ref>