CUCKOOS AND THEIR HABITS

[To the Editor of THE Src-rifon.]

Sin,—Many an unedifying dispute regarding the dome§tie economy of the cuckoo might have been avoided if certain observers had not claimed for their observations, which in themselves were interesting, a too general application in their desire to dogmatise on unsubstantiated claims, based on -purely hypothetical evidence, and in attempting to generalise on the habits of a single species by propounding an entirely new theory on assumed photographic evidence. It should be carefully noted that neither Mr. Pike nor Mr. Chance makes any attempt to reply to the main implication contained in my letter—i.e., that photography, as far as the actual deposition is concerned, has so far proved absolutely nothing. I have before me a letter from the latter in which it' is stated " that

photographs are unsatisfactory." I also have another commu- nication froth the same observer in which he claims, in referring to his slow motion film " in this you actually see the egg leaving the oviduct." Why does Mr. Pike -not publish this photo ? Has anyone seen it ? To claim that a cuckoo " like any other bird lays its eggs directly into the place where they

are to be hatched " without deducing carefully verified scientific evidence is untenable.

Both Messrs. Chance and Pike endeavour to enlarge on the point that when the cuckoo arrived at the nest she first picked up and held in her beak the fosterer's egg. In every case when I have personally witnessed depositions by regurgitation, the fosterer's egg has been always taken up immediately after the deposition. It was impossible for me—and equally impossible for them—to see the cuckoo's egg leave the beak while her head was in the nest ; immediately before she takes up the fosterer's egg this obviously is exactly what takes place.

I will now " face up " to the three questions put by Mr. Chance. The very beautiful silver-point drawing by Dr. Rowan-L–as reproduced in Country Life—was exhibited before the members of the British Ornithologists' Club at a subse-

quent meeting (as it was not then ready) on October 12th, 1927, at which I read my paper on the deposition which I saw, in company with Mr. Scholey, on the Cliffe-at-Hoo, Kent, marshes on June 20th, 1927. Does Mr. Chance honestly believe that Dr. Rowan would have ever put his pencil to that drawing if he had had any doubts as to the genuineness of my observation and statements ?

In the second part of question 1, he states that in connexion with an illustrated article by Mr. Scholey in a well-known weekly journal (presumably Country Life) that I personally witnessed with Mr. Scholey a cuckoo actually lay her egg. I only witnessed with him three depositions, and they were all by regurgitation. I have not—and do not wish to—conceal facts, but why does Mr. Chance make statements and accusa- tions before taking the trouble to verify them ? He suggests that Mr. Scholey no longer supports my statements. This, if

a fact, would indeed be staggering news—there is, however, not a word of truth in his claims,.

I have all Mr. Scholey's correspondence since we first met -very carefully preserved. This is what he says in a letter dated April 18th, 1932 :

"As photographs do not prove things to the right sort of critic, and a genuine deposition by regurgitation can, in a photograph be construed into a raid or anything else by a sceptic who won't have the regurgitation theory—now no longer a theory, thank goodness " (italics mine).'

In referring to my observations recorded in The Spectator for July 2Qth, .1934, he writes on July 27th : " Firstly, please accept my congratulations. Fairly knock out evidence."

If space permitted I could considerably enlarge on Mr. Scholey's emphatic support and evidence in confirmation of regurgitation.

Regarding Mr. Chance's question 3, in which he refers to wagers, I cannot .do better than refer him to the first para- graph in the above-mentioned letter in The Spectator. I would also like to call his attention to the Bulletin of the

British. Ornithologists' Club for April litth, 1925, and remind him of the fact that he was severely censured by the Com- mittee for endeavouring to .cliscredit Mr. Scholey's mind my own observations as reported to the Club in November, 1924,

and . for sending a report of that criticism to the Birmingham Mail without-the Committee's permission.

Mr. Pike ignominiously attempts to throw dust in the eyes of your readers by suggesting that I have. endeavoured to twist his statements in my effort to prove the habit of regurgi- tiiion. I do mit know what his statements were intended to convey. I- am only interested in his important confession ! As to whether Mr. Chance is pleased or not must be left to them to settle. Those who know Mr. Chance as I do (!) will find it difficult to believe that the confession was made without his consent.

It is well known that for fifteen years I have persistently, conscientiously, and perhaps indignantly, fought against the fantastic theory of normal oviposition which, as all ornitholo- gists are- well aware, was founded on the evidence of the original film, and I now claim that, owing to Mr. Pike's admission, the theory is.no longer tenable, and the thorn to which Mr. Pike refers has not even left a superficial scratch. I am well aware that thousands have seen. these films, but that by -no means proves anything.. Were they all convinced ? , Why he should suggest that I have purposely avoided -seeing his film is not only absurd, but untrue. Nothing would give me more pleasure, providing I was allowed a free hand to criticise, but I must repeat that none of my friends who have seen it accept the claims put forward as confirmatory evidence in support of normal oviposition.

It is quite possible that a Cuckoo has been seen on a nest. If so, she was definitely not there for oviposition. She was there as Darwin would have suggested (Origin of Species, p. 198) as a rare event—probably a case of temporary reversion to a long-lost aboriginal instinct of nidification-r---i.e., the love of brooding.

It is interesting to note that neither Mr. Chance nor Mr. Pike makes any effort to defend the photos which appeared in Country Life, and which I criticised in my letter. They prefer to indulge in empty innuendos and criminations instead of placing before us facts backed up by irrefutable new scien- tific evidence, and Mr, Pike does not explain what he means by a forcing .action, of the rump during oviposition. There is no forcing action required in the natural birth of an egg It is physically impossible for any bird to lay an egg in one- fifth of a second !

In conclusion, it may interest them to know that I am perfectly satisfied with the support that has been and is being given to the habit of regurgitation by many leading Ornitholo- gists. There probably will always be a vociferous minority who are slow in accepting what is now a proved fact=in many cases because they have been deceived by photos and the impossible claims put forward by photographers. Where Mr. Scholey and I have scored is that most of our work has been with the Reed Warbler Cuckoo ; consequently the whole of the nest and the body of the bird is in full view to those in the hide during deposition.—I am, Sir, &c.,

PERCY F. BUNYARD, F.Z.S., M.B.O.U.

- 57 Kidderminster- Road, Croydon.

[We cannot continue this correspondence.—ED. The Spectator.]