I am sure we all have noticed an ominous disclosure in most online birding forums: “No Nesting pictures”. This is of course a well meaning and prudent notice. Nothing can do more harm than an over enthusiastic photographer who wants to photograph nests, eggs and fledglings. He might cause unnecessary alarm of the parent bird. This might result in abandoning of the nests with eggs and chicks in them. It disrupts the breeding success of our country’s already fragile bird populations. Even if the parent birds don’t abandon the nests, his actions might lead predators to the nest which then proceeds to devour the hapless chicks and eggs. In addition, in climbing towards the nest, he might accidentally break the branch on which the nest is resting again destroying the nest and its contents.
It might be surprising to our readers that not
so long ago, collecting eggs of wild birds was the part of most school higher
secondary zoology curriculums! Thankfully some educationist saw the futility of
this exercise and did away with it. Our passerine birds will be ever so
thankful to these anonymous educationists.
Despite all this, it is more important than
ever to revisit our nesting knowledge. India has about 1300 species of birds.
Roughly a third of this number is resident birds and rest is cross border
migrants. It is quite unfortunate that despite the work of many naturalists,
ornithologists and scientists, we still know so little about the nesting
behavior of our resident birds.
Most of the nesting knowledge comes from Naturalist
EC Stuart Baker’s Four Volume “Nidification of the birds of Indian empire”
published in 1932 [1].
To critique on his work, for lack of better words, I will paraphrase the words
of another author[2] “One of the most controversial collections was that
of E.C. Stuart Baker. He actually built up two collections, one of “Indian
Eggs” and the other of “Cuckoo Eggs”. The first of these covered the Indian
sub-continent, i.e. former British India. It was the most comprehensive egg
collection ever assembled for this area. I can think of no species of the area
for which the eggs are known and for which Baker did not have eggs. And there
are species for which he had the only eggs known. Knowledge of the nidification
of Indian sub-continent birds has hardly progressed at all since Baker’s time.
The other collection, of cuckoo’s eggs, was scarcely less comprehensive.
Needless to say it is based on the same area, where Baker spent most of his
collecting life, but he also had eggs sent to him from other parts of the Old
World - indeed everywhere where parasitic cuckoos occur. The problem with his
collection is that his data are often suspect. His handwriting is difficult,
but I have got used to it. He wrote with his left hand, not because he was
left-handed but because he had no right arm. In his youth he was on a tiger
hunt, and a leopard suddenly leaped out of the bushes and attacked him. The
only thing he could think of to do was to plunge his right arm down the tiger’s
throat with all the force he could muster. This action so startled the tiger
that it stopped it for the few vital seconds necessary to allow the beaters to
rush up and kill it. So, Baker lost his arm, but saved his life. When I began
to curate the Baker collection, I discovered that in lots of clutches there
were single eggs which did not seem to match the rest of the clutch. The
difference was subtle but, when one had got used to it, distinctive. If you
examined the writing on these eggs, sometimes one found that the date was
slightly different from that on the rest of the clutch. But then again,
sometimes one found the same anomaly on eggs which didn’t perceptively differ
from those of the rest of the clutch. The question was always: is this a
genuine clerical error, or is it an attempt to deceive? Baker lived in an era
when egg collecting and the buying and selling of eggs were perfectly legal and
indeed big business. Large clutches were more collectable and therefore more
valuable than smaller ones. The temptation in front of dealers (and Baker
“dealt” in eggs in a big way) was to add eggs that sort-of matched to existing
clutches to make them into larger ones. A story is told of Baker, though it may
be apocryphal. A visitor called to see him one day and the door was answered by
one of his children, who said “Oh Daddy’s upstairs making up clutches”. As I
said, I have no proof that this story is true, but it inevitably raised doubts
as to Baker’s integrity. There were a number of suggestions over the years, by,
I think, Charles Vaurie among others that the Baker collection was so
unreliable that it should be destroyed. But the collection is so vast and so
well written-up in the published literature that it cannot be ignored. All one
could do was to go through it with a toothcomb and note carefully every little
thing that seemed to be doubtful, which is exactly what I did. Future workers
must take it from there”.
From this account, it
must be clear to our readers the suspicious quality of Stuart baker’s work.
Most of the ornithological works which followed used Stuart baker’s unreliable
information without taking the effort to obtain firsthand knowledge. Salim
Ali in his Book of Indian Birds chapter on “Some nests and nesting behaviour”
puts his aspirations regarding our knowledge on bird nesting behaviours in the
following words-“We have a great deal to learn about the
breeding biology of even some of our commonest birds. Egg collecting
alone is not enough. Some of the points on which detailed information is
desirable are- (1) The share of the sexes in nest building, incubation and care
of the young; (2) Periods of incubation; (3) Intervals between the laying of
each egg in a clutch; (4) Nature of food and quantity fed each day to the
young; (5) Behaviour of parents and young”[3]
When I visited Salim Ali bird sanctuary in Thattekad in February 2015, I
had the opportunity to interact with Dr Sukadhan, the field ornithologists and
one of the old timers who had opportunity to work alongside Dr Salim ali.
During our inteation, he stressed upon the urgency in the need to revisit
Nidification work of Indian birds considering the rapid decline in many
species. Unless, we know adequately enough about the ecology of the birds and
their nesting behaviour, it is difficult to come up with fruitful management
plans for conservation and proliferation of our native bird species.
At the moment, as Coimbatore nature society, if we are to record nesting
behaviour of our native birds, it is important to frame some guidelines and
rules which will enable us to make some
meaningful observations without
disturbing the bird species. I have no doubt that we are up to the challenge
and together, we can do it. We can we will.
[1] The book is very difficult to
locate. A scanned version of the four volume can be located here: https://archive.org/details/NidificationOfBirdsOfTheIndianEmpire1
Zool. Med. Leiden 79-3 (1), 30-ix-2005, 5-18.— ISSN
0024-0672.
Michael Walters, Bird Group, The Natural History Museum,
Akeman Street, Tring, Herts, HP23 6AP,
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