Bird nest
A bird nest is the spot in which a bird lays and
Not all bird species build nests. Some species lay their eggs directly on the ground or rocky ledges, while
In the majority of nest-building species the female does most or all of the nest construction, in others both partners contribute; sometimes the male builds the nest and the hen lines it.[5][6] In some polygynous species, however, the male does most or all of the nest building. The nest may also form a part of the courtship display such as in weaver birds. The ability to choose and maintain good nest sites and build high quality nests may be selected for by females in these species. In some species the young from previous broods may also act as helpers for the adults.
Type
Not every bird species builds or uses a nest. Some auks, for instance—including common murre, thick-billed murre and razorbill—lay their eggs directly onto the narrow rocky ledges they use as breeding sites.[7] The eggs of these species are dramatically pointed at one end, so that they roll in a circle when disturbed. This is critical for the survival of the developing eggs, as there are no nests to keep them from rolling off the side of the cliff. Presumably because of the vulnerability of their unprotected eggs, parent birds of these auk species rarely leave them unattended.[8] Nest location and architecture is strongly influenced by local topography and other abiotic factors.[9]
King penguins and emperor penguins also do not build nests; instead, they tuck their eggs and chicks between their feet and folds of skin on their lower bellies. They are thus able to move about while incubating, though in practice only the emperor penguin regularly does so. Emperor penguins breed during the harshest months of the Antarctic winter, and their mobility allows them to form huge huddled masses which help them to withstand the extremely high winds and low temperatures of the season. Without the ability to share body heat (temperatures in the centre of tight groups can be as much as 10C above the ambient air temperature), the penguins would expend far more energy trying to stay warm, and breeding attempts would probably fail.[10]
Some crevice-nesting species, including
Scrape
The simplest nest construction is the scrape, which is merely a shallow depression in soil or vegetation. are among the species that build scrape nests.
Eggs and young in scrape nests, and the adults that brood them, are more exposed to
In cool climates (such as in the high
In warm climates, such as
The technique used to construct a scrape nest varies slightly depending on the species. Beach-nesting terns, for instance, fashion their nests by rocking their bodies on the
Mound
Burying eggs as a form of incubation reaches its zenith with the
In most mound-building species, males do most or all of the nest construction and maintenance. Using his strong legs and feet, the male scrapes together material from the area around his chosen nest site, gradually building a
Both the temperature and the moisture content of the mound are critical to the survival and development of the eggs, so both are carefully regulated for the entire length of the breeding season (which may last for as long as eight months), principally by the male.
Flamingos make a different type of mound nest. Using their beaks to pull material towards them,[44] they fashion a cone-shaped pile of mud between 15–46 cm (6–18 in) tall, with a small depression in the top to house their single egg.[45] The height of the nest varies with the substrate upon which it is built; those on clay sites are taller on average than those on dry or sandy sites.[44] The height of the nest and the circular, often water-filled trench which surrounds it (the result of the removal of material for the nest) help to protect the egg from fluctuating water levels and excessive heat at ground level. In East Africa, for example, temperatures at the top of the nest mound average some 20 °C (36 °F) cooler than those of the surrounding ground.[44]
The base of the
Burrow
Soil plays a different role in the burrow nest; here, the eggs and young—and in most cases the incubating parent bird—are sheltered under the earth. Most burrow-nesting birds excavate their own burrows, but some use those excavated by other species and are known as secondary nesters;
Most burrow nesting species dig a horizontal tunnel into a vertical (or nearly vertical) dirt cliff, with a chamber at the tunnel's end to house the eggs.
Birds use a combination of their beaks and feet to excavate burrow nests. The tunnel is started with the beak; the bird either probes at the ground to create a depression, or flies toward its chosen nest site on a cliff wall and hits it with its bill. The latter method is not without its dangers; there are reports of kingfishers being fatally injured in such attempts.[49] Some birds remove tunnel material with their bills, while others use their bodies or shovel the dirt out with one or both feet. Female paradise-kingfishers are known to use their long tails to clear the loose soil.[49]
Some
Not all burrow-nesting species incubate their young directly. Some megapode species bury their eggs in sandy pits dug where sunlight, subterranean volcanic activity, or decaying tree roots will warm the eggs.[1][38] The crab plover also uses a burrow nest, the warmth of which allows it to leave the eggs unattended for as long as 58 hours.[60]
Predation levels on some burrow-nesting species can be quite high; on
Cavity
The cavity nest is a chamber, typically in living or dead wood, but sometimes in the trunks of
Woodpeckers use their chisel-like bills to excavate their cavity nests, a process which takes, on average, about two weeks.[64] Cavities are normally excavated on the downward-facing side of a branch, presumably to make it more difficult for predators to access the nest, and to reduce the chance that rain floods the nest.[68] There is also some evidence that fungal rot may make the wood on the underside of leaning trunks and branches easier to excavate.[68] Most woodpeckers use a cavity for only a single year. The endangered red-cockaded woodpecker is an exception; it takes far longer—up to two years—to excavate its nest cavity, and may reuse it for more than two decades.[64] The typical woodpecker nest has a short horizontal tunnel which leads to a vertical chamber within the trunk. The size and shape of the chamber depends on species, and the entrance hole is typically only as large as is needed to allow access for the adult birds. While wood chips are removed during the excavation process, most species line the floor of the cavity with a fresh bed of them before laying their eggs.
Trogons excavate their nests by chewing cavities into very soft dead wood; some species make completely enclosed chambers (accessed by upward-slanting entrance tunnels), while others—like the extravagantly plumed resplendent quetzal—construct more open niches.[66] In most trogon species, both sexes help with nest construction. The process may take several months, and a single pair may start several excavations before finding a tree or stump with wood of the right consistency.
Species which use natural cavities or old woodpecker nests sometimes line the cavity with soft material such as grass, moss, lichen, feathers or fur. Though a number of studies have attempted to determine whether secondary cavity nesters preferentially choose cavities with entrance holes facing certain directions, the results remain inconclusive.[69] While some species appear to preferentially choose holes with certain orientations, studies (to date) have not shown consistent differences in fledging rates between nests oriented in different directions.[69]
Cavity-dwelling species have to contend with the danger of predators accessing their nest, catching them and their young inside and unable to get out.[70] They have a variety of methods for decreasing the likelihood of this happening. Red-cockaded woodpeckers peel bark around the entrance, and drill wells above and below the hole; since they nest in live trees, the resulting flow of resin forms a barrier that prevents snakes from reaching the nests.[71] Red-breasted nuthatches smear sap around the entrance holes to their nests, while white-breasted nuthatches rub foul-smelling insects around theirs.[72] Eurasian nuthatches wall up part of their entrance holes with mud, decreasing the size and sometimes extending the tunnel part of the chamber. Most female hornbills seal themselves into their cavity nests, using a combination of mud (in some species brought by their mates), food remains and their own droppings to reduce the entrance hole to a narrow slit.[73]
A few birds are known to use the nests of insects within which they create a cavity in which they lay their eggs. These include the rufous woodpecker which nests in the arboreal nests of Crematogaster ants and the collared kingfisher which uses termite nests.[74]
Cup
The cup nest is smoothly hemispherical inside, with a deep depression to house the eggs. Most are made of pliable materials—including grasses—though a small number are made of mud or saliva.[75] Many passerines and a few non-passerines, including some hummingbirds and some swifts, build this type of nest.
Small bird species in more than 20 passerine families, and a few non-passerines—including most hummingbirds, kinglets and crests in the genus Regulus, some tyrant flycatchers and several New World warblers—use considerable amounts of spider silk in the construction of their nests.[76][77] The lightweight material is strong and extremely flexible, allowing the nest to mold to the adult during incubation (reducing heat loss), then to stretch to accommodate the growing nestlings; as it is sticky, it also helps to bind the nest to the branch or leaf to which it is attached.[77]
Many swifts and some hummingbirds[78] use thick, quick-drying saliva to anchor their nests. The chimney swift starts by dabbing two globs of saliva onto the wall of a chimney or tree trunk. In flight, it breaks a small twig from a tree and presses it into the saliva, angling the twig downwards so that the central part of the nest is the lowest. It continues adding globs of saliva and twigs until it has made a crescent-shaped cup.[79]
Cup-shaped nest insulation has been found to be related to nest mass,[80][81] nest wall thickness,[81][82][83] nest depth,[80][81] nest weave density/porosity,[80][82][84] surface area,[81] height above ground[80] and elevation above sea level.[84]
More recently, nest insulation has been found to be related to the mass of the incubating parent.
Saucer or plate
The saucer or plate nest, though superficially similar to a cup nest, has at most only a shallow depression to house the eggs.
Platform
The platform nest is a large structure, often many times the size of the (typically large) bird which has built it. Depending on the species, these nests can be on the ground or elevated.[85] In the case of raptor nests, or eyries (also spelled aerie), these are often used for many years, with new material added each breeding season. In some cases, the nests grow large enough to cause structural damage to the tree itself, particularly during bad storms where the weight of the nest can cause additional stress on wind-tossed branches.
Pendent
The pendent nest is an elongated sac woven of pliable materials such as grasses and plant fibers and suspended from a branch. Oropendolas, caciques, orioles, weavers and sunbirds are among the species that weave pendent nests. In weaver birds, this is pendant, suspended from a single point hanging from branch while many other birds incorporate more than one branch to support the nest.
Sphere
The sphere nest is a roundish structure; it is completely enclosed, except for a small opening which allows access. Most spherical nests are woven out of plant material. Spider webs are also frequently used, upon which other material such as lichens may be stuck for camouflage. The cape penduline tit incorporates false entrances, the parent bird carefully making sure to close the actual entrance when leaving the nest. The entrances are lined with spider webs which help seal the openings.[86]
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.[87] 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 grebes 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.[88]
Many species attack predators or apparent predators near their nests. Kingbirds attack other birds that come too close. In North America, northern mockingbirds, blue jays, and Arctic terns can peck hard enough to draw blood.[89] 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.[90]
Nests can become home to many other organisms including parasites and pathogens.[91] The excreta of the fledglings also pose a problem. In most passerines, the adults actively dispose the fecal sacs of young at a distance or consume them. This is believed to help prevent ground predators from detecting nests.[92] Young birds of prey however usually void their excreta beyond the rims of their nests.[93] Blowflies of the genus Protocalliphora have specialized to become obligate nest parasites with the maggots feeding on the blood of nestlings.[94]
Some birds have been shown to choose aromatic green plant material for constructing nests that may have insecticidal properties,[95][96] while others may use materials such as carnivore scat to repel smaller predators.[97] 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.[98][99]
Some birds use pieces of snake slough in their nests.[100] It has been suggested that these may deter some nest predators such as squirrels.[101]
Colonial nesting
Though most birds nest individually, some species—including
Ecological importance
In constructing nests, birds act as ecosystem engineers by providing a sheltered microclimate and concentrated food sources for invertebrates.[103] A global checklist lists eighteen invertebrate orders that occur in bird nests.[104]
In human culture
Many birds may nest close to human habitations. In addition to nest boxes which are often used to encourage cavity nesting birds (see below), other species have been specially encouraged : for example nesting white storks have been protected and held in reverence in many cultures,[105] and the nesting of peregrine falcons on tall modern or historical buildings has captured popular interest.[106]
Colonial breeders produce guano in and around their nesting sites, which is a valuable fertilizer from the Andean Pacific coast and other areas.
The saliva nest of the edible-nest swiftlet is used to make bird's nest soup,[107] long considered a delicacy in China.[108] Collection of the swiftlet nests is big business: in one year, more than 3.5 million nests were exported from Borneo to China,[109] and the industry was estimated at $1 billion US per year (and increasing) in 2008.[107] While the collection is regulated in some areas (at the Gomantong Caves, for example, where nests can be collected only from February to April or July to September), it is not in others, and the swiftlets are declining in areas where the harvest reaches unsustainable levels.[107]
Some species of birds are considered nuisances when they nest in the proximity of human habitations.
The Beijing National Stadium, principal venue of the 2008 Summer Olympics, has been nicknamed "The Bird Nest" because of its architectural design, which its designers likened to a bird's woven nest.[111]
In the 19th and early 20th centuries,
Artificial bird nests
Bird nests are also built by humans to help in the conservation of certain birds (such as swallows). Swallow nests are generally built with plaster, wood, terracotta or stucco.[113][114]
Artificial nests, such as nest boxes, are an important conservation tool for many species, however nest box programs rarely compare their effectiveness with individuals not using nest boxes. Red-footed falcons using nest boxes in heavily managed landscapes produced fewer fledglings than those nesting in natural nests, but also than pairs nesting in nest boxes in more natural habitats.[115]
References
Notes
- ^ a b c Campbell & Lack 1985, p. 386
- ^ Campbell & Lack 1985, p. 345
- .
- ^ smithsonianscience.org 2015-04-20 Bird nests: Variety is Key for the world's avian Architects Archived 3 January 2017 at the Wayback Machine
- ^ Campbell & Lack 1985, p. 387
- ISBN 0-7064-0236-7.
- ^ Ehrlich et al. 1994, pp. 228–232
- ^ del Hoyo 1992, p. 692
- ^ Hogan 2010.
- ^ del Hoyo 1992, p. 148
- ^ Ehrlich et al. 1994, p. 252
- ^ Ehrlich et al. 1994, p. 260
- ^ Cohn-Haft 1999, p. 295
- ^ Jaramillo 2001, p. 548
- ^ Short & Horne 2002b, p. 282
- ^ JE, Simon; Pacheco (2005), "On the standardization of nest descriptions of neotropical birds" (PDF), Revista Brasileira de Ornitologia, 13 (2): 143–154, archived (PDF) from the original on 20 July 2008
- ^ Campbell & Lack 1985, p. 390
- ^ Ehrlich et al. 1994, p. xxii
- ^ Ehrlich et al. 1994, p. 441
- ^ Campbell & Lack 1985, p. 174
- ^ Campbell & Lack 1985, p. 145
- ISBN 978-0-19-517194-5
- .
- JSTOR 4535956.
- ^ Grant 1982, p. 11.
- ^ Grant 1982, p. 60.
- JSTOR 1365438.
- ^ Grant 1982, p. 61.
- ^ Grant 1982, p. 62.
- ^ del Hoyo, Elliott & Sargatal 1996, p. 637
- ^ del Hoyo, Elliott & Sargatal 1996, p. 673
- ^ del Hoyo 1992, p. 80
- ^ del Hoyo 1992, p. 119
- ^ del Hoyo, Elliott & Sargatal 1996, p. 222
- ^ del Hoyo, Elliott & Sargatal 1996, p. 473
- ^ del Hoyo 1992, p. 558
- ^ del Hoyo, Elliott & Sargatal 1996, p. 371
- ^ a b c d Elliott 1994, p. 287
- ^ Hansell 2000, p. 9.
- ^ a b Elliott 1994, p. 288
- ^ Elliott 1994, p. 280
- ^ Elliott 1994, p. 289
- ^ a b c del Hoyo 1992, p. 516
- ^ Seng 2001, p. 188
- ISBN 978-1-873403-59-4
- ^ Behrstock 2001, p. 344
- ^ Harrap & Quinn 1996, p. 21
- ^ a b c d Woodall 2001, p. 169
- JSTOR 5635
- ^ Ehrlich et al. 1994, p. xxiii
- ^ Ehrlich et al. 1994, p. 345
- ^ Juniper & Parr 2003, p. 24
- ^ Rasmussen & Collar 2002, p. 119
- ^ Short & Horne 2002a, p. 162
- hdl:2381/31362.
- S2CID 22934726.
- PMID 12966063.
- ISBN 978-0-470-04517-6
- ^ Boersma, P. Dee; Wheelwright, Nathaniel T.; Nerini, Mary K.; Wheelwright, Eugenia Stevens (April 1980), "The Breeding Biology of the Fork-tailed Storm-Petrel (Oceandroma furcata)" (PDF), Auk, 97 (2): 268–282, archived (PDF) from the original on 21 August 2014
- ^ Ehrlich et al. 1994, p. 17
- ^ a b Collar 2001, p. 94
- ^ a b c Reed 2001, pp. 380–1
- (PDF) from the original on 28 January 2016
- ^ a b Collar 2001, p. 96
- ^ Phillips, Tina (Winter 2005), "Nest Boxes: More than Just Birdhouses", BirdScope, 19 (1), archived from the original on 19 July 2007
- ^ a b Conner 1975, p. 373
- ^ a b Rendell, Wallace B.; Robertson, Raleigh J. (1994), "Cavity Entry Orientation and Nest-site Use by Secondary Hole-nesting Birds" (PDF), Journal of Field Ornithology, 65 (1): 27–35, archived (PDF) from the original on 4 March 2016
- ISBN 978-0-292-75532-1
- ^ Rudolph, Kyle & Conner 1990
- ^ Reed 2001, p. 437
- ^ Kemp 2001, p. 469
- .
- ^ Hansell 2000, p. 280.
- ^ Ehrlich et al. 1994, p. 445
- ^ a b Erickson, Laura (Spring 2008), "The Wonders of Spider Silk", BirdScope, 22 (2): 7
- ^ Gould & Gould 2007, p. 200.
- ^ Gould & Gould 2007, p. 196.
- ^ JSTOR 1366826
- ^ PMID 21325330
- ^
- ^ Whittow, F.N.; Berger, A.J. (1977), "Heat loss from the nest of the Hawaiian honeycreeper, 'Amakihi'", Wilson Bulletin, 89: 480–483
- ^ JSTOR 1366825
- ISBN 978-0-7575-0997-1
- ISSN 0030-6525.
- ^ Rudolph, Kyle & Conner 1990.
- ^ Byrktedal 1989
- ^ Gill 1995
- ^ Kaplan 2004
- ^ Hicks, Ellis A. (1959), Checklist and bibliography on the occurrence of insects in birds' nests, Iowa State College Press, Ames
- ^ Petit, Petit & Petit 1989
- ^ Rosenfeld, Rosenfeld & Gratson 1982
- ^ Sabrosky, Bennett & Whitworth 1989
- ^ Wimberger 1984
- ^ Clark & Mason 1985
- ^ Schuetz 2005
- ISSN 0908-8857.
- PMID 23221874.
- (PDF) from the original on 24 December 2013
- S2CID 86039366
- ^ Ward & Zahavi 1973
- S2CID 91557693.
- JSTOR 3492142.
- JSTOR 1521775.
- ^ Cade & Bird 1990
- ^ ISBN 978-0-520-25932-4
- ISBN 978-0-313-38058-7, archivedfrom the original on 4 June 2013
- ISBN 978-81-7141-933-3, archivedfrom the original on 3 June 2013
- ^ Haag-Wackernagel & Moch 2004
- ^ "Competition entries for design of Beijing National Stadium". Beijing Municipal Commission of Urban Planning. Archived from the original on 20 February 2008. Retrieved 25 February 2008.
- ^ Dixon, Charles (1902), Birds' nests, New York: Frederick A Stokes, p. v
- ^ Artificial swallow nests Archived 17 March 2014 at the Wayback Machine
- ^ Terracotta nests Archived 17 March 2014 at the Wayback Machine
- .
Cited texts
- Behrstock, Robert A. (2001), "Typical Owls", in Elphick, Chris; Dunning, John B. Jr.; Sibley, David (eds.), The Sibley Guide to Bird Life & Behaviour, London: Christopher Helm, ISBN 978-0-7136-6250-4
- Byrktedal, Ingvar (1989), "Nest defense behavior of Lesser Golden-Plovers" (PDF), Wilson Bull., 101 (4): 579–590
- Cade, T.J.; Bird, D.M. (1990), "Peregrine Falcons (Falco peregrinus) nesting in an urban environment: a review", Can. Field-Nat., 104 (2): 209–218, doi:10.5962/p.356349
- Campbell, Bruce; Lack, Elizabeth, eds. (1985), A Dictionary of Birds, Carlton, England: T and A D Poyser, ISBN 978-0-85661-039-4
- Clark, L.; Mason, J. Russell (1985), "Use of nest material as insecticidal and anti-pathogenic agents by the European Starling", Oecologia, 67 (2): 169–176, S2CID 32307579
- Cohn-Haft, Mario (1999), "Family Nyctibiidae (Potoos)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-25-2
- Collar, N. J. (2001), "Family Trogonidae (Trogons)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-30-6
- Collias, Nicholas E. (1997), "On the origin and evolution of nest building by passerine birds" (PDF), Condor, 99 (2): 253–270, JSTOR 1369932
- Conner, Richard N. (1975), "Orientation of entrances to woodpecker nest cavities", Auk, 92 (2): 371–374, JSTOR 4084566
- del Hoyo, Josep (1992), "Family Phoenicopteridae (Flamingos)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-10-8
- del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi, eds. (1996), ISBN 978-84-87334-20-7
- ISBN 978-0-19-858407-0
- Elliott, Andrew (1994), "Family Megapodiidae (Megapodes)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-15-3
- Gould, James L; Gould, Carol Grant (2007), Animal Architects: Building and the Evolution of Intelligence, New York, NY: Basic Books, ISBN 978-0-465-02782-8
- Grant, Gilbert (1982), Avian Incubation in a Hot Environment, Ornithological Monographs, vol. 30, Washington, DC: ISBN 978-0-943610-30-6
- Haag-Wackernagel, D; Moch, H. (2004), "Health hazards posed by feral pigeons", J. Infect., 48 (4): 307–313, PMID 15066331
- Gill, Frank B. (1995), Ornithology, Macmillan, p. 383, ISBN 978-0-7167-2415-5, retrieved 16 December 2009
- Hansell, Mike (2000), Bird Nests and Construction Behaviour, Cambridge University Press, ISBN 978-0-521-01764-0
- Harrap, Simon; Quinn, David (1996), Tits, Nuthatches & Treecreepers, London: Christopher Helm, ISBN 978-0-7136-3964-3
- Hogan, C. Michael (2010), "Abiotic factor", in Emily Monosson; C. Cleveland (eds.), Encyclopedia of Earth, Washington DC: National Council for Science and the Environment, archived from the original on 8 June 2013
- Jaramillo, Alvaro (2001), "Blackbirds, Orioles and Allies", in Elphick, Chris; Dunning, John B. Jr.; Sibley, David (eds.), The Sibley Guide to Bird Life & Behaviour, London: Christopher Helm, ISBN 978-0-7136-6250-4
- Juniper, Tony; Parr, Mike (2003), Parrots: A Guide to the Parrots of the World, London: Christopher Helm, ISBN 978-0-7136-6933-6
- Kaplan, Gisela (2004), Australian Magpie: Biology and Behaviour of an Unusual Songbird, Melbourne, Victoria: CSIRO Publishing, p. 121, ISBN 978-0-643-09068-2, retrieved 16 December 2009
- Kemp, A. C. (2001), "Family Bucerotidae (Hornbills)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-30-6
- Petit, Kenneth E.; Petit, Lisa J.; Petit, Daniel R. (1989), "Fecal Sac Removal: Do the Pattern and Distance of Dispersal Affect the Chance of Nest Predation?" (PDF), The Condor, 91 (2): 479–482, JSTOR 1368331
- Reed, J. Michael (2001), "Woodpeckers and Allies", in Elphick, Chris; Dunning, John B. Jr.; Sibley, David (eds.), The Sibley Guide to Bird Life & Behaviour, London: Christopher Helm, ISBN 978-0-7136-6250-4
- Rasmussen, Pamela C.; Collar, Nigel J. (2002), "Family Bucconidae (Puffbirds)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-37-5
- Rosenfeld, R.N.; Rosenfeld, A. J.; Gratson, M. W. (1982), "Unusual Nest Sanitation by a Broad-Winged Hawk" (PDF), The Wilson Bulletin, 94 (3): 2365–366
- Rudolph, D. C.; Kyle, H.; Conner, R. N. (1990), "Red-cockaded woodpeckers vs. Rat Snakes: The effectiveness of the resin barrier" (PDF), Wilson Bull., 102 (l): 14–22
- Sabrosky, Curtis W.; Bennett, G. F.; Whitworth, T. L. (1989), Bird blow-flies (Protocalliphora) (Diptera: Calliphoridae) in North America with notes on the Palearctic species, Washington, DC: Smithsonian Institution Press
- Schuetz, Justin G. (2005), "Common waxbills use carnivore scat to reduce the risk of nest predation", Behavioral Ecology, 16 (1): 133–137, doi:10.1093/beheco/arh139, archived from the originalon 13 January 2013
- Seng, William J. (2001), "Flamingos", in Elphick, Chris; Dunning, John B. Jr.; Sibley, David (eds.), The Sibley Guide to Bird Life & Behaviour, London: Christopher Helm, ISBN 978-0-7136-6250-4
- Short, Lester L.; Horne, Jennifer F. M. (2002a), "Family Capitonidae (Barbets)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-37-5
- Short, Lester L.; Horne, Jennifer F. M. (2002b), "Family Indicatoridae (Honeyguides)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-37-5
- Skowron, C; Kern, M. (1980), "The insulation in nests of selected North-American songbirds", Auk, 97 (4): 816–824,
- Ward, P.; Zahavi, A. (1973), "The importance of certain assemblages of birds as "information centers" for food finding", Ibis, 115 (4): 517–534,
- Whittow, F.N.; Berger, A.J. (1977), "Heat loss from the nest of the Hawaiian honeycreeper, 'Amakihi'", Wilson Bulletin, 89: 480–483
- Wimberger, P. H. (1984), "The use of green plant material in bird nests to avoid ectoparasites" (PDF), Auk, 101 (3): 615–616,
- Woodall, Peter F. (2001), "Family Alcedinidae (Kingfishers)", in del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi (eds.), ISBN 978-84-87334-30-6