
Oology (or oölogy) is a branch of
ornithology
Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and th ...
studying
bird egg
Bird eggs are laid by the females and range in quantity from one (as in condors) to up to seventeen (the grey partridge). Clutch size may vary latitudinally within a species. Some birds lay eggs even when the eggs have not been fertilized; it i ...
s,
nests and breeding behaviour. The word is derived from the Greek ''oion'', meaning egg. Oology can also refer to the hobby of collecting wild birds' eggs, sometimes called egg collecting, birdnesting or egging, which is now illegal in many jurisdictions.
History
As a science

Oology became increasingly popular in Britain and the United States during the 1800s. Observing birds from afar was difficult because high quality
binoculars
Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes ( binocular vision) when viewing distant objects. Most binoculars are sized to be hel ...
were not readily available.
Thus it was often more practical to shoot the birds or collect their eggs. While the collection of the eggs of wild birds by amateurs was considered a respectable scientific pursuit in the 19th century and early 20th century, from the mid 20th century onwards it was increasingly regarded as being a hobby rather than a scientific discipline.
In the 1960s, the naturalist
Derek Ratcliffe compared
peregrine falcon
The peregrine falcon (''Falco peregrinus''), also known as the peregrine, and historically as the duck hawk in North America, is a cosmopolitan bird of prey ( raptor) in the family Falconidae. A large, crow-sized falcon, it has a blue-grey ...
eggs from historical collections with more recent egg-shell samples, and was able to demonstrate a decline in shell thickness.
This was found to cause the link between the use by farmers of
pesticides
Pesticides are substances that are meant to pest control, control pest (organism), pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microb ...
such as
DDT
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. ...
and
dieldrin
Dieldrin is an organochloride originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. Dieldrin is closely related to aldrin, which reacts further to form dieldrin. Aldrin is not toxic to insects; it is oxidized in the insect to f ...
, and the decline of British populations of birds of prey.
As a hobby
Egg collecting was still popular in the early 20th century, even as its scientific value became less prominent. Egg collectors built large collections and traded with one another. Frequently, collectors would go to extreme lengths to obtain eggs of rare birds. For example,
Charles Bendire
Major Charles Emil Bendire (April 27, 1836 – February 4, 1897) was a United States Army soldier and noted ornithologist and oologist. The Bendire's thrasher is named for him.
Early life
Born Karl Emil Bender at König im Odenwald in the Gra ...
was willing to have his teeth broken to remove a rare egg that became stuck in his mouth. He had placed the egg in his mouth while climbing down a tree.
In 1922, the British Oological Association was founded by
Baron Rothschild
Baron Rothschild, of Tring in the County of Hertfordshire, is a title in the Peerage of the United Kingdom. It was created in 1885 for Sir Nathan Rothschild, 2nd Baronet, a member of the Rothschild banking family. He was the first Jewish mem ...
, a prominent naturalist, and the
Reverend Francis Jourdain; the group was renamed the
Jourdain Society
The Jourdain Society is or was a controversial society based in the United Kingdom, its aims being ‘the advancement of the science of oology’, the collection and study of intact birds' eggs. Established in 1922 as the British Oological Associ ...
after Jourdain's death in 1940. Rothschild and Jourdain founded it as a breakaway group after egg collecting by members of the
British Ornithologists' Union
The British Ornithologists' Union (BOU) aims to encourage the study of birds (" ornithology") and around the world, in order to understand their biology and to aid their conservation. The BOU was founded in 1858 by Professor Alfred Newton, ...
, was denounced by
Earl Buxton at a meeting of the
Royal Society for the Protection of Birds
The Royal Society for the Protection of Birds (RSPB) is a charitable organisation registered in England and Wales and in Scotland. It was founded in 1889. It works to promote conservation and protection of birds and the wider environment throu ...
.
Poaching laws
In the UK
Legislation, such as the
Protection of Birds Act 1954 and
Wildlife and Countryside Act 1981
The Wildlife and Countryside Act 1981 is an Act of Parliament in the United Kingdom implemented to comply with European Council Directive 79/409/EEC on the conservation of wild birds. In short, the act gives protection to native species (especia ...
in the United Kingdom, has made it impossible to collect wild birds' eggs legally. In the United Kingdom, it is only legal to possess a wild-bird's egg if it was taken before 1954, or with a permit for scientific research; selling wild birds' eggs, regardless of their age, is illegal.
However, the practice of egg collecting, or egging, continues as an underground or illegal activity in the UK and elsewhere.
In the 1980s and 1990s, the fines allowed by the law were only a moderate deterrent to some egg collectors.
However, the
Countryside and Rights of Way Act 2000
The Countryside and Rights of Way Act 2000 (c. 37), known informally as the CRoW Act or "Right to Roam" Act is a United Kingdom Act of Parliament affecting England and Wales which came into force on 30 November 2000.
Right to roam
The Act imp ...
allowed for six months' imprisonment for the possession of the eggs of wild birds
and, since it came into force, a number of individuals have been imprisoned, both for possessing and for attempting to buy egg collections.
The Jourdain Society continued to meet although membership dwindled after 1994, when a dinner of the society was raided by police, assisted by the Royal Society for the Protection of Birds (RSPB). This resulted in six members being convicted and fined.
Despite this, some of those who engage in egg collecting show considerable
recidivism
Recidivism (; from ''recidive'' and ''ism'', from Latin ''recidīvus'' "recurring", from ''re-'' "back" and ''cadō'' "I fall") is the act of a person repeating an undesirable behavior after they have experienced negative consequences of th ...
in their activity. One,
Colin Watson, was convicted six times before he fell to his death in 2006, while attempting to climb to a nest high up in a tree. While the threat of imprisonment after 2000 encouraged some to give up egg collecting,
others were not deterred. One individual has been convicted ten times and imprisoned twice. As recently as 2018, a man was imprisoned for amassing a collection of 5000 eggs, after previously being imprisoned in 2005. Another man was convicted of possessing 200 eggs in 2021.
The Royal Society for the Protection of Birds has been particularly active in fighting illegal egg collection and maintains an investigative unit that collects intelligence on egg collectors and assists police in mounting prosecutions on them, in addition to investigating other wildlife crimes.
At one point, RSPB staff were being trained by soldiers from the
Brigade of Gurkhas
The Brigade of Gurkhas is the collective name which refers to all the units in the British Army that are composed of Nepalese Gurkha soldiers. The brigade draws its heritage from Gurkha units that originally served in the British Indian Army ...
in camouflage skills and in surveillance, map and radio techniques, to better enable them to guard nests of rare birds.
In the United Kingdom, to avoid the possibility of prosecution, owners of old egg collections must retain sufficient proof to show, on the balance of probabilities, that the eggs pre-date 1981. However owners of genuinely old collections are unlikely to face prosecution as experienced investigators and prosecutors are able to distinguish them from recently collected eggs.
It is illegal to sell a collection, regardless of the eggs' age, so old collections may only be disposed of by giving the eggs away or by destroying them. Museums are reluctant to accept donations of collections without reliable collection data (i.e. date and place that they were collected) that gives them scientific value. Also, museums no longer put egg collections on public display.
In the US
In the United States, the collection and possession of wild bird eggs is also restricted, and in some cases is a criminal act. Depending on the species, the
Migratory Bird Treaty Act
The Migratory Bird Treaty Act of 1918 (MBTA), codified at (although §709 is omitted), is a United States federal law, first enacted in 1918 to implement the convention for the protection of migratory birds between the United States and Canada . ...
, the
Lacey Act
The Lacey Act of 1900 is a conservation law in the United States that prohibits trade in wildlife, fish, and plants that have been illegally taken, possessed, transported, or sold.United States. Lacey Act (Game). , ch. 553. Approved May 25, 1900. ...
, the
Endangered Species Act
The Endangered Species Act of 1973 (ESA or "The Act"; 16 U.S.C. § 1531 et seq.) is the primary law in the United States for protecting imperiled species. Designed to protect critically imperiled species from extinction as a "consequence of e ...
, or other laws may apply.
Collecting
Methods
When collecting eggs, normally the whole clutch of eggs is taken. Because eggs will rot if the contents are left inside, they must be "blown" to remove the contents. Although collectors will take eggs at all stages of incubation, freshly laid eggs are much easier to blow, usually through a small, inconspicuous hole drilled with a specialized drill through the side of the eggshell. Egg blowing is also done with domestic bird's eggs for the hobby of
egg decorating
Egg decorating is the art or craft of decorating eggs. It has been a popular art form throughout history because of the attractive, smooth, oval shape of the egg, and the ancient associations with eggs as a religious and cultural symbol. Egg dec ...
.
Major research collections
*
Natural History Museum
A natural history museum or museum of natural history is a scientific institution with natural history collections that include current and historical records of animals, plants, fungi, ecosystems, geology, paleontology, climatology, and more ...
(610,000 eggs), UK
*
Delaware Museum of Natural History
The Delaware Museum of Nature & Science (DMNS) is a museum located since January 1, 2022. The museum was founded in 1957 by John Eleuthere du Pont near Greenville, Delaware; it opened in 1972 on a site near Winterthur, Delaware. It is known fo ...
(520,000 eggs), US
*
H. L. White Collection
The H. L. White Collection is a collection of Australian birds’ eggs originally accumulated by wealthy pastoralist, amateur ornithologist and oologist Henry Luke White (1860-1927). On White's death it passed to the National Museum of Victoria i ...
, Melbourne, Australia
*
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. It has free admission and is open 364 days a year. In 2021, with ...
(190,000 eggs), Washington DC, US
*
Muséum de Toulouse
The Muséum de Toulouse (, MHNT) is a museum of natural history in Toulouse, France. It is in the Busca-Montplaisir, houses a collection of more than 2.5 million items, and has some of exhibition space. Its Index Herbariorum code is TLM. ...
(150,000 eggs), Toulouse France
*
San Bernardino County Museum (41,000 clutches with 135,000 eggs)
*
Western Foundation of Vertebrate Zoology (190,000 clutches with >800,000 eggs), California, US
*
Santa Barbara Museum of Natural History
The Santa Barbara Museum of Natural History is a natural history museum in Santa Barbara, California.
It reconnects more than 150,000 people each year (including their 5,700 members) to nature indoors and outdoors. Nestled in nature, the museum ...
(formerly the Museum of Comparative Oology) (11,000 egg sets from 1,300 species), Santa Barbara, California, US
Oologists and egg collectors
*
Charles Bendire
Major Charles Emil Bendire (April 27, 1836 – February 4, 1897) was a United States Army soldier and noted ornithologist and oologist. The Bendire's thrasher is named for him.
Early life
Born Karl Emil Bender at König im Odenwald in the Gra ...
*
Archibald James Campbell
Archibald James Campbell (18 February 1853 – 11 September 1929) was an Australian civil servant in the Victorian (later Australian) government Customs Service. However, his international reputation rests on his expertise as an amateur ornit ...
, author of ''Nests and Eggs of Australian Birds, Including the Geographical Distribution of the Species and Popular Observations Thereon'' (Sheffield England, Pawson & Brailsford, 1900) Reissued 1974, by Wren, Melbourne, Victoria, Australia
*
E. J. Court
E is the fifth letter of the Latin alphabet.
E or e may also refer to:
Commerce and transportation
* €, the symbol for the euro, the European Union's standard currency unit
* ℮, the estimated sign, an EU symbol indicating that the weig ...
of
Washington, DC
)
, image_skyline =
, image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morgan, ...
*
Charles Johnson Maynard
Charles Johnson Maynard (May 6, 1845 – October 15, 1929) was an American naturalist and ornithologist born in Newton, Massachusetts. He was a collector, a taxidermist, and an expert on the vocal organs of birds. In addition to birds, he also s ...
, author of ''Eggs of North American Birds'' (Boston: DeWolfe, Fiske & Co., 1890)
*
Francis Charles Robert Jourdain
The Reverend Francis Charles Robert Jourdain M.A., F.Z.S., M.B.O.U. (4 March 1865 – 27 February 1940), was a notable British amateur ornithologist and oologist. He was primarily known for his extensive research into the breeding biology of ...
*
Colin Watson
Oology related publications
Numerous books, and at one point a journal, have been published on egg collecting and identification:
*
Thomas Mayo Brewer Thomas Mayo Brewer (November 21, 1814 – January 24, 1880) was an American naturalist, specializing in ornithology and oology.
Biography
Thomas Mayo Brewer was born in Boston, the younger brother of noted Boston merchant Gardner Brewer. He ...
, (1814–80), an American
ornithologist
Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and th ...
, wrote most of the biographical sketches in the ''History of North American Birds'', by Baird, Brewer, and
Ridgway (1874–84). He has been called "the father of American oölogy". He wrote ''North American Oölogy'' which was partially published in 1857.
*
William Chapman Hewitson
William Chapman Hewitson (9 January 1806, in Newcastle upon Tyne – 28 May 1878, in Oatlands Park, Surrey) was a British natural history, naturalist. A wealthy collector, Hewitson was particularly devoted to Coleoptera (beetles) and Lepidopter ...
, ''Illustrations of Eggs of British Birds'', (third edition, London, 1856).
*
Archibald James Campbell
Archibald James Campbell (18 February 1853 – 11 September 1929) was an Australian civil servant in the Victorian (later Australian) government Customs Service. However, his international reputation rests on his expertise as an amateur ornit ...
, ''Nests and Eggs of Australian Birds: Embracing Papers On "Oology of Australian Birds," Read Before the Field Naturalists' Club of Victoria, Supplemented by Other Notes & Memoranda ; Also, an Appendix of Several Outs - Nesting, Shooting Etc.'', (A. J. Campbell, Melbourne, Victoria, Australia, 1883) (Cover title: ''Oology of Australian Birds''. Ferguson no. 7870)
*
Oliver Davie, ''Nests and Eggs of North American Birds'', (fifth edition, Columbus, 1898).
*
Alfred Newton
Alfred Newton FRS HFRSE (11 June 18297 June 1907) was an English zoologist and ornithologist. Newton was Professor of Comparative Anatomy at Cambridge University from 1866 to 1907. Among his numerous publications were a four-volume ''Dictiona ...
, ''Dictionary of Birds'', (New York, 1893–96).
*
*
''The Oologist''(journal)
In popular culture
* A 2007 episode of ''
Midsomer Murders
''Midsomer Murders'' is a British crime drama television series, adapted by Anthony Horowitz and Douglas Watkinson from the novels in the '' Chief Inspector Barnaby'' book series (created by Caroline Graham), and broadcast on two channels of ...
'' "Birds of Prey" surrounds illegal oology.
* In 2017 Artist
Andy Holden and father, ornithologist Peter Holden, staged a series of exhibitions titled ''Natural Selection'', staged by
Artangel
Artangel is a London-based arts organisation founded in 1985 by Roger Took. Directed since 1991 by James Lingwood and Michael Morris, it has commissioned and produced a string of notable site-specific works, plus several projects for TV, film, ...
, which took place at Bristol Museum,
Towner Gallery
Towner Art Gallery is located in Eastbourne, East Sussex, on the south coast of England.
It hosts one of the most significant public art collections in the South of England and draws over 100,000 visitors a year. It was described by ITV News a ...
in Eastbourne, and
Leeds Art Gallery
Leeds Art Gallery in Leeds, West Yorkshire, England, is a gallery, part of the Leeds Museums & Galleries group, whose collection of 20th-century British Art was designated by the British government in 1997 as a collection "of national importance ...
, in which they explored the ‘social history’ of oology in Britain. The exhibition included a vast recreation of an illegal egg collection, as well as a film narrating the history of egg collecting in Britain.
See also
*
Jourdain Society
The Jourdain Society is or was a controversial society based in the United Kingdom, its aims being ‘the advancement of the science of oology’, the collection and study of intact birds' eggs. Established in 1922 as the British Oological Associ ...
References
External links
*
Alberto Masi Egg Gallery''Poached'' a 2015 film documentary about illegal egg collecting.
{{Authority control
Ornithology