The Story of O(ology)

BY: Bob Montgomerie, Queen’s University | 15 April 2019

After a seminar last week, my colleague Jannice Friedman, a botanist, asked me if ‘oology’ was really a word, as it had appeared on one of the speaker’s slides. So, she asked, what is the ‘o’ that ‘ology’ (the study of) has been tacked on to? I explained to her that oology (or oölogy) is the study of eggs, and birds’ eggs in particular, but I had no idea why it was not something more logical like ‘ovology’ [1]. Oology is one of those words like ‘popsicle’ and ‘’castle’ that are familiar but then sound ridiculous when you think about them or repeat them too often [2].

W. C. Hewitson

The OED says that oology first appeared in print in English in 1830, in an advertisement [3] for the soon-to-be-published British Oology by William Hewitson. Hewitson published this ‘book’ as a series of fascicles, sold by subscription beginning in 1831 and completed in 1838. The second (1843-44) and third editions (1856) were called Coloured Illustrations of the Eggs of British Birds. Among the subscribers to that first edition were such notables as John James Audubon, John Gould, W. J. Hooker, Sir William Jardine, Prideaux John Selby, and William Yarrell [4]. It was clearly a popular publication on a popular topic.

Hewitson’s British Oology starts with an Introduction in which he waxes poetic about his love of Nature, and the pleasures of egg-collecting: “who does not remember those joyous times when, at the first breaking loose from school, he has hied him to the wood and the hedge-row, in search of his painted prize?”[5] In that first edition, he describes the eggs and nests of 229 species that bred in Britain, illustrated with coloured plates that he drew on lithographic stone and then hand-coloured. Those plates, curiously, show no more than four eggs per page, all life size, and thus the plates are often mostly white space (see below).

Some of the eggs shown in British Oology

Like most pre-Darwinian naturalists, Hewitson saw in the design of eggs some God-given purpose for the good of mankind: “For the same purpose for which they adorn the plumes of the Humming-bird, or the wing of the resplendent butterfly — to gladden our eyes, ‘To minister delight to man, to beautify the earth.’ And thus it is that the eggs of nearly all those birds (the Owl, Kingfisher, Bee-cater, Holler, Nuthatch, and the Woodpeckers) which conceal them in holes, are white, because in such situations colour would be displayed to no purpose.” [5].

Even in the interspecific variation in clutch size, Hewitson saw the hand of God providing for mankind: “In every instance we shall find the same beneficent influence acting for our welfare; increasing rapidly, by the number of their eggs, those species which are of the greatest use to us, and bestowing upon those intended for our more immediate benefit, a most wonderful power of ovo-production; and at the same time curtailing in their numbers those species which, in their greater increase would soon become injurious to us.” [5]

Despite all of that teleology, Hewitson was perceptive in noting that species with precocial offspring have eggs that are larger relative to female size compared to species with altricial hatchlings. He also concludes that egg colour cannot be generally useful for camouflage except in a few ground-nesting birds. With respect to the use of eggs in taxonomy, he has a mixed message but still seems to want to cling to the idea that egg traits will be useful for classification [6]. His descriptions of breeding habitats, nest construction, breeding seasons and clutch sizes provide a useful window on the state of knowledge about British birds almost two centuries ago.

I assume that the word ‘oology’ was already in general use when Hewitson published British Oology because he uses the term without definition or special mention, as if all readers would know what he was talking about. For the next century oology was a prominent topic among people interested in birds, the subject of several books, myriad papers, and even a museum of oology [7] in Santa Barbara, California. Hewitson later turned his attention to collecting and illustrating lepidoptera, but occasionally dabbled in oology, mainly updating his British Oology with papers on new discoveries in the British Isles and continental Europe.

So where did that word ‘oology’ come from? The OED says that it is a combination of ‘oo’ and ‘logy’ but that really does not make sense to me as ‘ology’— not ‘logy’—is the standard suffix meaning ‘the scientific study of’. For example, Wikipedia lists 342 ‘ologies’ all of which appear to append ‘ology’ onto a subject of study: bi-ology, ichthy-ology, ornith-ology. The OED also says that ‘oologia’ is the Latin version first used in 1691, probably derived from ‘oion’ Greek word for egg. My guess is that it’s a word that egg collectors made up to give their hobby a patina of science.

The word ‘oology’ became associated with egg-collecting in the Victorian era but largely disappeared from the ornithological literature in the 1920s, probably because egg-collecting fell out of favour (and was eventually outlawed). The study of eggs waxed and waned throughout the twentieth century with a monumental book—The Avian Egg—by AL and AJ Romanoff published in 1949 being one of the highlights. Over the past decade or so, the study of bird’s eggs has enjoyed a resurgence with new tools available for measuring colours and shapes but few ornithologists use the word oology any more.

Recent books about bird’s eggs


  • Anonymous (1908) Mr. W. C. Hewitson. The Ibis Jubilee Supplement 2: 182–185.
  • Birkhead T (2016) The Most Perfect Thing: Inside (and Outside) a Bird’s Egg. Bloomsbury USA.
  • Hewitson WC (1831-38) British oology: being illustrations of the eggs of British birds, with figures of each species, as far as practicable, drawn and coloured from nature : accompanied by descriptions of the materials and situation of their nests, number of eggs, &c. Newcastle Upon Tyne: Charles Empson [first edition available here]
  • Hewitson WC (1859) Recent discoveries in European oology. The Ibis 1: 76-80
  • Kiff L (2005) History, present status, and future prospects of avian eggshell collections in North America. The Auk 122: 994–999,


  1. ovology: is, according to the dictionary, one variant of oology but I have seen it in print
  2. sound ridiculous when you think about them or repeat them: this is called semantic satiation or wordnesia and can happen with any word
  3. advertisement: in Magazine of Natural History 3 (end matter)—”On the First of January, 1831, will be published, the First Number of British Oology, being illustrations of the Eggs, Nidification, &c. of British Birds
  4. subscribers to British Oology: the full list is at the beginning of the first edition.
  5. Hewitson quotations: from Hewitson 1831 pages 3, 8, and 8-9, respectively
  6. useful for classification: this idea persisted well into the 20th century despite ample evidence that it eggs were not a useful trait for taxonomy. I expect that some of this persistence was driven by a desire to justify the collecting of eggs
  7. museum of oology: the Museum of Comparative Oölogy was started by William L. Dawson in 1916, and is now part of the Santa Barbara Museum of Natural History

Summertime and the Birdin’ is easy

BY: Bob Montgomerie, Queen’s University | 9 July 2018

Most of my birder friends don’t do much birding in the summer unless they are involved in breeding bird surveys. Once the flush of spring migration, Global Big Days, and the frenzy of territory establishment have passed, most of them spend the summer months from mid-June to mid-August catching up on their reading, bringing their e-bird lists up-to-date, and planning birding trips for the fall.

Acadian Flycatcher nest & eggs, Rondeau Prov Park, Ontario, 1969

It wasn’t always like this. For many bird enthusiasts, the summer months were the most exciting, because that’s when birds were nesting and egg-collecting was an all-consuming hobby. Even as recently as the 1970s, my old friend George Peck [1] and I spent most of our summer weekends haunting the woods and fields around Toronto in search of nests and eggs to photograph. George was what I might call a reformed öologist—an egg collector—who turned his attention to photographing rather than collecting birds’ eggs when that hobby became not only illegal [2] but scorned and prosecutable in the 1960s. George was a professional veterinarian who was well aware that prosecution for egg-collecting would destroy his career.


When I first met George in the mid 1960s he still had his boyhood egg collection, as it was still legal to possess one then, even though you could not legally collect wild birds’ eggs. With the advent of Kodachrome II and decent colour photography George made it his goal—his life list, if you will—to photograph the nest and eggs of every North American breeding bird, and to building the Ontario Nest Record Scheme into one of the largest and most accurate records of nesting birds ever compiled. George called himself a nidiologist, a term I never hear anymore.

Back in the day—as in the late 1800s—hundreds, no thousands, of men and boys (rarely women) would spend their spare time in summers hunting for birds’s nests and collecting eggs, for fun, for profit, or for science. Some wealthy men—like Walter Rothschild and Johnny Dupont—made huge collections that became the nucleus of many of the large collections in museums today. 

coverAnd there was money to be made because often the wealthiest of collectors did not go into the field at all, but amassed their collections through barter and purchase. For some men, egg collecting was an important source of seasonal income, and thousands of eggs were bought and sold both in personal transactions and by dealers. One dealer, Watkins & Doncaster [3], in 1900, would sell you a Golden Eagle egg for 18/6 ($119.64 in today’s $US), or a Honey Buzzard egg for 7/0 ($45.36 today) [4]. Even the egg of a common British garden bird like the Blackbird would cost 7d (54 cents). As you might expect, price was driven by supply and demand, and demand was driven by the rarity of the bird and the egg pattern [5]. Even given the vendor’s markup, a man could make a decent wage collecting birds’ eggs during the summer.



I would never advocate a return to egg-collecting as a hobby or a vocation, but as I have mentioned before, the great—and scientifically important and useful—egg collections of the world have stagnated, having added precious few specimens for decades. Many of them are also poorly curated, protected, and catalogued, though recently I have seen some  renewed interest on the part of museum curators.

As a working scientist, I can’t even watch birds or record their songs without approval from our Animal Care Committee, let alone find nests and photograph eggs. The general public, of course, is not so restricted, but there is little amateur interest in nests and eggs anymore. Done carefully, and maybe under permit, there would seem to be some value in a renewed interest in nidiology, but that might be too fraught with conservation issues to be very attractive to most people.

There are, of course, always books to read in the summer, and this year there is a superb crop of books for those interested in reading about birds. I have the following pile of books relevant to the history of ornithology on my desk, and will write reviews of most of them in the coming weeks. For now, just a brief description of each book is about.

  • WMWBirkhead TR (2018) The Wonderful Mr Willughby: The first true ornithologist. London: Bloomsbury. [Francis Willughy and John Ray tried to revolutionize natural history in the 17th century. Their classic Ornithologia Tres Libris was really the first encyclopedia of ornithology, with detailed description of all the species known to them. Willughby died when he was only 36, so Ray wrote up all of their findings in classic works on ornithology, fishes and insects. Ray got most of the glory….until now]
  • Brunner B (2017) Birdmania: A remarkable passion for birds. Vancouver: Greystone Books. [A somewhat eclectic compilation of interesting stories about some of the characters that populate the history of ornithology.]
  • Johnson KW (2018) The Feather Thief: Beauty, obsession, and the natural history heist of the century. London: Hutchinson. [The intriguing story of Edwin List who stole valuable bird specimens from the British Museum to get feathers to make expensive flies for fishing]
  • dresserMacGhie HA (2017) Henry Dresser and Victorian Ornithology: Birds, books and business. Manchester: Manchester University Press [While the focus here is on the life of Henry Dresser, from Manchester, UK, this book is a superb window on the state of ornithology in the late 1800s]
  • Olina GP (2018) Pasta for Nightingales: A 17th century handbook of bird-care and Folklore. New Haven, CT: Yale University Press [this is the first English translation, by Kate Clayton, of one of the classics of early ornithology written ins 1622. Replete with contemporary watercolours from Olina’s day.]
  • skelZalasiewicz J, Williams M (2018) Skeletons: The frame of life. Oxford: Oxford University Press [Despite the cover photo, there is not much in this book about birds, but what there is is fascinating, and nicely places birds in the evolution of skeletons. I have already reviewed this book for Times Higher Education in the 14-20 June 2018 issue]


  1. George Peck: was mentioned in my previous posts here, here and here
  2. egg-collecting illegal: In the UK the Protection of Birds Act of 1954 made the colection of birds’ eggs illegal. In tNorth America, that protection began with the Migratory Birds Treaty Act of 1918, but egg collecting continued largely unprosecuted until the UK act of the 1950s. The history of these laws and their enforcement is definitely complex and will be the subject of a later post
  3. Watkins & Doncaster: established in 1874, is still in business, though they no longer sell birds’ eggs. They moved from their location on The Strand in London in 1956, and are now in Hertfordshire (and, of course, on the internet)
  4. egg prices: are listed as shillings/pence in their catalog. I used this site to convert those amounts to today’s currency.
  5. rarity of egg pattern: see here for my previous post on an interesting and rare egg pattern

Red Eggs


BY: Tim Birkhead, University of Sheffield | 30 April 2018

Common guillemot eggs on Skomer, Wales showing some of the variety

The cover or frontispiece of almost every book about birds’ eggs is adorned with a picture of a common guillemot (Common Murre [1]) egg. Why? There are several reasons—the common guillemot’s egg is an extraordinary shape, it’s brightly coloured, and the variation in the colour and maculation seems almost infinite.

Egg collectors, or oölogists as they called themselves, accumulated collections of eggs mainly for aesthetic reasons, and there are few eggs more aesthetic of those of the guillemot. Collectors also liked to display the range of variation in egg colour. With the exception of one or two species like the tawny-flanked prinia Prinia subflava [2], there is more variation in the colours and patterns of guillemot eggs than any other species.

That variation is apparent if you open a museum draw of guillemot eggs. But it is a fraction of the variation apparent in freshly laid eggs on the ledges where these birds breed. Eggs in museum collections often fade unless protected from the light, and I have seen many an old collection where almost all the eggs have converged to a pale, muddy, bluish-green background colour. The markings, which are always darker, seem not to fade, so much of the variation in guillemot one sees in museums is in those maculations. Oölogists described those maculation as ‘salt and pepper’, ‘black cap’, ‘lose cap’, ‘shorthand’, and ‘scrawl’. Ornithologists have been more pragmatic and less poetic.

The majority of common guillemot eggs have a blue, green or white ground colour over which lie the various forms of maculation. In their competitive quest for eggs, oölogists sought—and sometimes fought over—the rarest types. This was especially true at Bempton Cliffs on the Flamborough Headland on England’s northeastern coast, where egging was an industry in the mid-nineteenth and mid-twentieth century. Tens of thousands of guillemot eggs were collected at Bempton each year, mainly for food, but also for the oölogists’ cabinets. Providing you were a wealthy enough oölogist, these were easy pickings. Farm labourers, known locally as ‘climmers’ (climbers) did all the work and took all the risks, scaling the 400-foot vertical cliffs to get the eggs. The collectors merely patrolled the cliff tops waiting to see what the climmers brought up.

Some Bempton ‘climmers’ in 1911 with some of the eggs they collected. William Wilkinson is in the middle.

It was a market: the climmers knew what the collectors wanted, and negotiated hard for a decent price. Farm labourers’ salaries were low and selling eggs was an important source of additional income for the climmers.  At a time when £3 was a decent weekly wage (for anyone, let alone a farm worker), an unusually coloured egg that sold for £1 was real bonus. The commoner egg shapes and colours went for a few pennies. The rarest guillemot eggs of all were those of a port-wine or blood red colour. The esteem with which such eggs were held was celebrated by the nick-name ‘Bempton Belle’ given to one egg from Bempton. Strictly speaking, the name should have referred to the female that laid this red egg since female guillemots always produce the same type and colour of egg.

When Bob Montgomerie and I visited the fabulous egg collection at the Delaware Museum of Natural History (DMNH) [3]  we found the following typewritten poem tucked into the bottom of one of the small egg boxes in a drawer full of guillemot eggs:


Listen Boys until I tell,
Of the famous egg — the Bempton Belle.
Seventeen days in June had gone;
When Jack the Climber came upon,
And brought from off the cliffs the Red;
The best ever seen by the veteran Ned.
William the Jumper struck with awe;
Said that a better egg he never saw.
Even silent Edwin Colley speaks,
Of the shape, and beautiful streaks.
The Boys all wondered at the shell,
Of the famous Red, the Bempton Belle.
Collectors who came from far and near,
Said they had never seen its peer.
Every man was fair to own,
The Bempton Belle the best egg known.
Jack the Here of the find;
Saved the egg for friendship kind.
Remember Boys the lesson taught;
True friendship can not be bought. [4]

This particular egg was part of Jeremiah Goodall’s egg collection (now in the DMNH) that he accumulated in the early 1900s. We don’t know whether it was Goodall who wrote the poem, but someone has added in pen that ‘Jack’ was Jack Hodgson, ‘Ned’ was Ned Hodgson and ‘William the Jumper’ was William Wilkinson, all climmers.

The Bempton Belle (left) now quite faded, and a 3D-printed replica (right) painted to represent how the Bempton Belle might have looked when it was fresh [5].
The colour of all birds’ eggs is determined by just two pigments, biliverdin and protoporphyrin IX. Our analyses show that red guillemot eggs contain only the latter pigment, as one might expect. Some other birds, and especially corvids—which typically lay greenish or blueish eggs—occasionally lay entire clutches of red eggs, referred to as ‘erythristic’, and these too were popular with egg collectors. Red guillemot eggs are essentially erythristic, albeit with heavy maculation.

We have attempted to assess just how rare such eggs were, and after looking at our own data and those of other guillemot researchers, we estimate that fewer than one in 1000, or possibly 10,000 female guillemots produce such extraordinary eggs [6].


  • Birkhead TR, Montgomerie R (2018) Rare red eggs of the Common Guillemot: birds, biology and people at Bempton, Yorkshire, in the early 1900s. Archives of Natural History 45: 69-79.
  • Boehm EF (1950) Abnormal erythrism in birds’ eggs. Emu 50:139.
  • Caves EM, Stevens M, Iversen E, Spottiswoode CN (2015) Hosts of brood parasites have evolved egg signatures with elevated information content. Proceedings of the Royal Society of London B 282: 20150598.
  • Gill F, Donsker D, Eds (2018) IOC World Bird List (v8.1). doi: 14344/IOC.ML.8.1. Online at
  • Gross AO (1966) Erythristic eggs. The Wilson Bulletin 78: 127–128.
  • Rarer ECS (1918) IV.‐Erythrism in bids’ eggs: an address read at the Third Oological Dinner on 26 September, 1917. Ibis 60: 68–75.


  1. common guillemot: The ‘official’ name of this species (Uria aalge) is Common Murre according to Gill and Donsker (2018) and HBW Alive/Bird Life International. Common guillemot is the name still used for this species in the UK.
  2. prinia egg colours: see Cave et al. (2015)
  3. Delaware Museum of Natural History: just north of Wilmington, this museum was established
  4. poem: See Birkhead and Montgomerie (2018) for a picture of the original. On that typescript someone has added some details in pen, and changed the last line and added two more: Honest Jack could not be bought/To your children the story tell/Of Jack the Climber, & the Bempton Belle.
  5. Bempton Belle photo: the actual egg now in the collection at DMNH; I painted the replica to show what the original probably have looked like, based on red guillemot eggs currently in the collection of the Natural History Museum at Tring (see Birkhead and Montgomerie 2018, Figure 1)
  6. rarity of erythristic guillemot eggs: see Birkhead and Montgomerie (2018) on the Bempton Belle and erythrism in murre eggs. See also Boehm (1950), Gross (1966), and Rarer (1918) on erythrism in birds’ eggs in general. Erythrism is either the result of addition protoporphyrin IX being added to the shell by the female, of biliverdin not being added to a shell that normally would have both pigments.

IMAGES: Bempton ‘climmers from an old postcard; Bempton Belle poem and photo © Delaware Museum of Natural History, used with permission of Dr Jean Woods, Curator of Birds; photo of guillemot eggs on Skomer and replica red egg © T R Birkhead.

The Utmost Harmony

BY: Bob Montgomerie, Queen’s University | 9 April 2018

I gave my first research talk at a ‘big’ international conference at the AOU meeting at Haverford College (Pennsylvania) in 1976. I talked about my work on Mexican hummingbirds and I was nervous, in part because Frank Gill—who was then doing great work on hummingbirds—was talking right before me. The chair of our session was some old guy with unruly grey hair. Though I really wanted to hear Frank’s talk, I was too busy thinking about what I was going to say to actually pay attention to his words. Until, that is, when he finished answering a couple of questions. As he was about to leave the stage, Frank said to the chair “Thanks, Ernst”. “OMG”, I thought [1], “that’s Ernst Mayr, and I may not survive this.”

Ernst Mayr ca 1976

I completed my presentation on autopilot, out of sheer terror. But Professor Mayr asked me a couple of excellent questions and thereby, very graciously, put me at ease and made my presentation seem like a success. I had been to a few AOU meetings before but that incident convinced me that I had found my academic home. It seemed that everyone from the most famous—Mayr and Gill—to the greenest student (me) could talk about birds in an environment characterized by the utmost harmony.

Indeed, that’s how someone [2] described the first AOU meeting, in a report in the Bulletin of the Nuttall Ornithological Club in 1883:

The session of the Convention occupied three days, and was marked throughout with the utmost harmony; at adjournment…hearty expressions of satisfaction with the results of the session were heard from all who had shared in its deliberations. The general good feeling rose to a degree of enthusiasm auguring well for the future work and prosperity of the Union, the organization of which, under such auspicious circumstances, cannot fail to mark an important era in the progress of ornithology in America. [3]

He was right, that first convention did augur well for the future work of the ‘Union’—and it has gone from strength to strength over the past 135 years. The AOU was the gifted child of the Nuttall Ornithological Club in 1883 and the proud parent (along with the Cooper Ornithological Society) of the American Ornithological Society (AOS) in 2016.

El Conquistador Hotel, Tucson, Where the 2nd AOS meeting is about to begin on 11 April 2018

Today I am in Tucson waiting for the start of the 2nd annual AOS meeting. I am anticipating some great science, some reconnecting with old friends, and seeing some interesting birds. I am not really a birder and especially not a twitcher, so I will not make the trek to Madera Canyon to see the Elegant Trogon reported there last week. This morning though, I watched  a pair of Verdins building a nest, and spent an hour in the midst of a dozen pairs of courting Great-tailed Grackles. I always prefer watching behaviour over searching for rarities. But I digress.

That first AOU meeting in 1883 was the result of a letter sent on 1 August 1883 by three officials [4] of the Nuttall Ornithological Club to 46 American and 2 Canadian ornithologists,


You are cordially invited to attend a Convention of American Ornithologists, tiobe held in New York City, beginning on Seotember 26, 1883, for the ourpose of founding an AMERICAN ORNITHOLOGISTS UNION, upon a basis similar to that of the “British Ornithologists Union”…The object of the Union will be the promotion of social and scientific intercourse between American ornithologsts, and their cooperation in whatever may tend to the advancement of Ornithology in North America…” [3]

Twenty-one men attended the 3-day conference in the library if the American Museum of Natural History. They declared themselves to be founders of the AOU, along with Spencer Fullerton Baird and J A Allen who were unable to attend. Their first order of business was to establish a constitiution for the new society followed by the election of other ornigthologists—all men as far as I can tell—to various classes of membership: 21 Foreign, 20 Corresponding, and 81 Associate in addition to the 47 Active members that included the Founders.

They also established six committees that nicely reflected 5 of the major ornithological interests of the day: Classification of North American Birds, Migration, Avian Anatomy, Oölogy, and Faunal Areas. The sixth committee was charged “to investigate the eligibilibity or ineligibility of the European House Sparrow in North America”. I do not know what that sixth committee eventually decided, but it is clear from events over the next century that the House Sparrow did not care.


  • Anonymous (1883) The American Ornithologists’ Union. Bulletin of the Nuttall Ornithological Club 8: 221-226


1. OMG: I did not, of course, think that in 1976, as it did not enter the slang lexicon for another 20 years

2.  someone described that first AOU meeting: see Anonymous (1883); normally i would have assumed it was the editor of the journal but that was J A Allen who was ill and could not attend the meeting

3. quotations from Anonymous (1883)

4, three Nuttall Club officials: were J A Allen (editor of the Nuttall Bulletin), Elliott Coues (associate editor) and William Brewster (President of the Nuttall Club)

¿Hay huevos?

BY: Bob Montgomerie, Queen’s University | 2 April 2018

I did my PhD field work in Nayarit, Mexico, mainly in the coastal town of San Blas. On our first long drive there from Montreal, my fellow PhD student—Neil Brown—and I attempted to learn some basic Spanish, using a small Berlitz guide. Neil dropped me off just outside town, then headed off to his own study area near Tepic, in the mountains. I soon found a place to stay and went to the local tienda to get food. Wanting to try out my new Spanish, I asked the young male owner “¿Tiene huevos?” to which he gave a sheepish smirk and pointed to a basket on the counter full of fresh eggs. After a couple of weeks of this, he said he’d help me learn some Spanish, beginning with the proper way to ask for eggs (¿Hay huevos?)—I was really asking him if he had any testicles. My Spanish has not much improved in the intervening 45 years but my scientific interest in both eggs and testes has vastly expanded.

ONRS nest record card

Like generations of teenage boys before me, I collected birds’ eggs. Unlike most of them, however, my collection was almost entirely photographic. In 1965, while still in high school, I had the good fortune to meet George Peck, a veterinarian who had just volunteered at the Royal Ontario Museum to coordinate the Ontario Nest Records Scheme (ONRS). This ‘scheme’ began in 1956 as a collection of file cards, one per nest, summarizing details about the location, clutch or brood size, and, sometimes, the history and fate of a nest found in Ontario. The ONRS was modeled after a similar scheme run by the British Trust for Ornithology.

George Peck was then an avid birder and (former) egg collector who had made it his lifelong hobby to photograph the nest and eggs of every North American bird [1]. For several years we spent many a weekend searching for nests throughout southern Ontario, photographing their contents and, often, setting up blinds to watch and photograph the parents as well. By the mid-1960s egg-collecting was illegal in Ontario [2] so we only took (and preserved) eggs from abandoned nests. George was always extremely careful around birds’ nests to minimize the risk of disturbing the parents and he taught me a lot about being a careful observer and note-taker.

The exquisite nest and four eggs (plus one cowbird egg) of a Blue-gray Gnatcatcher, high in a maple tree at Rondeau Provincial Park, Ontario, in 1969 (R Montgomerie Photo)

Today the ONRS contains more than 120,000 nest records and provides a superb historical record of the distribution and other details (that George liked to call ‘nidiology’) of breeding birds in Ontario. Peck and James used these records to compile the first distributional and nidiological survey of breeding birds in Ontario, an early and quite successful product of citizen science.

I am writing this post on Easter Egg Weekend, at a time when we are seeing something of a renaissance in the scientific study of birds’ eggs. Just last Saturday (31 March), BBC TWO aired a special on The Wonder of Eggs, hosted (of course) by David Attenborough [3]. And last year, birds’ eggs were on the cover of Science, with a comprehensive paper on the evolution egg shape by Cassie Stoddard (Princeton Univ) and her colleagues. Recent books by Tim Birkhead (Univ Sheffield) in 2016 and Mark Hauber (Univ Illinois) in 2014 have respectively highlighted both the exquisite biology and the amazing diversity of bird’s eggs.

As a budding oölogist [4], I devoured the Romanoff’s 1949 classic The Avian Egg, but by the time I started graduate school in the 1970s research on birds’ eggs had largely fallen by the wayside. I suspect that the scientific study of wild birds’ eggs was a victim of the demonization of egg-collecting by conservation groups and the very strict laws that eventually became established in Europe and North America. In some places, these laws even make the private curation of an egg collection illegal and have lead to the—in my opinion senseless—destruction of countless egg collections.

huicholFGDLCFreud would undoubtedly have had a field day speculating on the association between egg-collecting and adolescent males. But I suspect he would have been wrong, as he was in much of what he wrote. While I was doing my PhD field work in San Blas, I met a local Huichol artist named Fermin Gonzalez de la Cruz who sold me a couple of his excellent yarn paintings. The details of one are shown to the right and were featured on the cover of National Geographic several years ago.

Huichol_shamanMany of the Huichol men that I encountered wore sombreros adorned around the rim with trinkets, and one of those men’s trinkets were mummified hummingbirds. I was studying hummingbirds, so this really intrigued me. When I asked him about it, he told me that hummingbirds were the traditional sombrero ornaments in his culture [5]. They were hard get, he said, so they became a sign that the bearer was a good hunter. As a budding behavioural ecologist, I interpreted that as a signal of status either to other males, or to potential mates. 

Birds eggs are one of several jewels of the bird world, not only beautiful but also delicate, hard to find, and (potentially) wearable. I do not know if there are any cultures that used bird eggs as ornaments but I do wonder if the European and North American obsession with egg collecting in the late 1800s was as much a signal of status as a desire to learn more about avian biology.

Regardless of the underlying psychology, the great egg collections now housed and curated in the museums of the world are a treasure trove of scientific and historical material—a subject that we will explore often on this site. Many avid (and, of course, male) collectors donated their large collections to—or indeed established—museums.

In Britain, the magnificent collection of more than a million eggs at the British Museum (Natural History), got a head start from an egg collector when Walter Rothschild donated his extensive collection (and his estate at Tring) in the 1930s. Similarly the superb egg collections at the Western Foundation of Vertebrate Zoology in Camarillo, California (by Ed Harrison) and the Delaware Museum of Natural History (by John du Pont) were both established by avid, even obsessive, egg collectors. In Britain, once the Protection of Birds Act [6] was passed in 1954, many private egg collections were destroyed by fearful owners, or zealous enforcers of the law [7].

Common Murre eggs at the Delaware Museum of Natural History

It is often said that we should study history to provide lessons for today. From the history of oölogy, we should have learned that egg collections: (i) are a valuable scientific resource, (ii) can help to solve some conservation problems [8], and (iii) are relatively easy to preserve. There is also no concrete evidence that the collecting of even thousands of eggs had any real impact on all but a very few very rare bird species. While I would never advocate the collecting of eggs as a hobby, as it once was, I feel that some of the current restrictions on scientific egg collecting are misguided.

When Paul Sweet of the American Museum of Natural History was asked recently how many eggs were in their collection [9], he answered, apparently without hesitation, 17,921. He knew that number precisely, he said, because it had not changed in years. That’s really a shame as there is much useful information being lost when museums do not maintain an active egg-collecting program, one that minimizes any possible damage to bird populations while maximizing the usefulness of the specimens through careful preservation, data collection and curation.


  • Birkhead T (2016) The Most Perfect Thing: Inside (and Outside) a Bird’s Egg. London: Bloomsbury.

  • HauberCoverHauber ME (2014) The Book of Eggs: A Guide to the Eggs of Six Hundred of the World’s Bird Species. Chicago: University of Chicago Press.

  • Peck GK, James RD (1987) Breeding birds of Ontario: nidiology and distribution (2). Toronto: Alger Press.

  • Ratcliffe  DA (1967). Decrease in eggshell weight in certain birds of prey. Nature 215: 208-210.
  • Romanoff AL, Romanoff AJ (1949) The Avian Egg. New York: John Wiley and Sons
  • Stoddard MC, Yong EH, Akkaynak D, Sheard C, Tobias JA, Mahadevan L (2017) Avian egg shape: Form, function, and evolution. Science 356: 1249-1254.


  1. George Peck: managed the ONRS for the rest of the century, elevating it to probably the best such set of nest records in North America. He continued to photograph nests and eggs until his eyesight failed him, coming very close to his goal of photographing all North American species. His son, Mark, now works at the ROM and continues his father’s interest in eggs and photography.
  2. egg collecting illegal in Ontario: as far as I can tell, egg collecting actually became illegal across North America, at least for migratory birds, with the Migratory Birds Convention Act of 1918. Apparently, that part of the act was rarely, if ever enforced with respect to the hobby, until the 1050s at least
  3. Attenborough’s Wonder of Eggs: has not yet aired in North America but you might be able to watch all of it (if you are in the UK) or some short clips on the BBC TWO website, and you can read about it here
  4. oölogist: literally means ‘one who studies’ eggs, but the term has been applied only to birds’ eggs; during the late 1800s and early 1900s ‘oölogist’ meant ‘egg collector’ so the term is not used very often today, except by scientists
  5. hummingbirds on sombreros: Some recent sources suggest that this story is apocryphal (though my story is true); while the hummingbird was imbued with mythological powers by the Huicholes, they apparently adorned their sombreros with a wide variety of natural objects in prehistoric times but now, like satin bowerbirds, use readily available man-made objects as decorations
  6. Protection of Birds Act of 1954: you can read a little bit about it here; I suspect that the passing of this Act had some influence on egg-collecting in North America, as well, even though egg-collecting had already been ‘illegal’ here for 36 years.
  7. destroying egg collections: Freud would undoubtedly have had a field day speculating on the psychology of the egg crushers
  8. egg collections solving conservation issue: the measurement of the eggs of some species in collections was key in pinpointing the effects of DDT on declining Peregrine Falcon populations (see Ratcliffe 1967)
  9. number of eggs in AMNH  collection: quoted in an article in The Atlantic

IMAGES: Huichol shaman from Wikipedia; all other photographs by the author