|Copyright: Emin Yogurtcuoglu (goldfinchtr)
|Date Taken: 2009-05-22|
|Exposure: f/7.1, 1/1000 seconds|
|More Photo Info: [view]|
|Photo Version: Original Version|
|Date Submitted: 2009-10-02 12:40|
|[Note Guidelines] Photographer's Note|
|Social behaviour of Jackdaws|
The jackdaw is a highly sociable species outside of the breeding season, occurring in flocks that can contain hundreds of birds.
Konrad Lorenz studied the complex social interactions that occur in groups of jackdaws and published his detailed observations of their social behaviour in his book King Solomon's Ring. To study jackdaws, Lorenz put coloured rings on the legs of the jackdaws that lived around his house in Altenberg, Austria for identification, and he caged them in the winter because of their annual migration away from Austria. His book describes his observations on jackdaws' hierarchical group structure, in which the higher-ranking birds are dominant over lower ranked birds. The book also records his observations on jackdaws' strong male–female bonding; he noted that each bird of a pair both have about the same rank in the hierarchy, and that a low-ranked female jackdaw rocketed up the jackdaw social ladder when she became the mate of a high-ranking male.
Every barnyard has a pecking order, as every farmer knows. Jackdaws like chickens establish a hierarchy. And the position of the individual jackdaw determines all pecking rights. Who may peck whom? No jackdaw may peck another who ranks higher in the order. This is known in zoology as a straight-line hierarchy. A high-ranking jackdaw may peck those of lower rank, and there is always that lowly jackdaw who is pecked by all, and can peck no one in return.
Jackdaws mate for life, and like most birds who follow this custom become engaged early in life, long before sexual maturity. First the young males of a new brood struggle among themselves to decide their individual status, and then pairing with females begins. The jackdaw female promptly upon pairing assumes the same social position of her male. His rights and restraints become her rights and restraints. Should a female not secure a mate, then it becomes a sad sort of story. She remains at the tail of all social things in a mournful, unclassified spot. She is last to the food and last to the shelter. She is pecked by the lowliest, snubbed by the least. Nor are there any lesser jackdaws on whom she can vent her frustration.
It was one of these sad, surplus females who revealed to Lorenz, through a train of circumstances, the full workings of the jackdaw social code:
Lorenz raised his flock from chicks. In the month before pairing and before rank order had been quite established one of the stronger males disappeared. At first Lorenz thought that the bird had gone off on an adventure and would return. But as weeks went by and he did not return, Lorenz checked the bird off as a probable victim of some watchful hawk. And he forgot him.
The flock proceeded with its social shakedown and the hierarchy was established. A strong, handsome young male secured the Number One position. ... Then pairing proceeded. ... Number One got a strong young female for his own, and together they made a handsome couple. On down the line the jackdaws paired, each male getting the approximate best that his rank could afford. And at the end of the line the completed pairing found two bedraggled females left over.
That was in the springtime. Mating would not take place for another year. The young jackdaw society settled down to the business of maturing: to the daily life of feeding and preening, of basking and growing, of praising one's fiancée and disparaging one's enemies. The top-ranking jackdaws found the aloofness proper to their aristocratic roles. The middle classes pecked at the lower classes, and the lower classes pecked at the unhappy spinsters. And then the vanished male returned.
No hawk had got the strong young bird but only wanderlust. Where he had been Lorenz could not guess. But here he was, after almost six months' absence, returned to a society where order had already been established and pairing completed. The problem of rank came first in the prodigal's instincts. He fixed Number one with a bright, metallic stare.
... It is Lorentz' opinion that the dominant relationship between two animals is established as much by the matching of energy, courage, and assurance as it is by strength. Perhaps the prodigal's adventures in far, desperate places had given him an assurance that no stay-at-home could match. Whatever were the determinants in the dignified struggle, there was little to observe. But by the second day it was all over: Number One had suddenly become Number Two, and the wanderer, Number One.
The problem of rank was settled; the problem of pairing remained. The new Number One assumed in the moment of his ascendancy all that aristocratic carriage which his eminence demanded. But he had no lady. He could not accept an appropriate consort from among the females already paired; jackdaws are faithful. The new Number One could take only one course, and he took it with dignity. He paired with one of the leftovers.
A female, we recall, takes the rank of her male. All in a happy hour the scrubby little female had become the President's wife. All in a happy hour the unwanted spinster from the wrong end of the pecking order had taken her place at the head. ... (She) found her days as a drudge behind her, the days of being pecked upon never to be repeated, the time of being last to the food, last to the shelter, of being snubbed, scorned, pushed about, crowded out, undefended, unloved, feared by none and rejected by all – it was a time that could be forgotten forever. But did she forget it? She did not.
... Number One's wife became the worst behaved nouveau in the history of jackdaw society. She snubbed, she flurried, she pushed about, she displayed her dreary plumage, fluttered her skinny wings, and pecked, and pecked, and pecked. In the moment of his ascendancy jackdaw instinct had directed her male to accept the aristocratic jackdaw role. But from the moment of her ascendancy all she apprehended were her rights. And she neglected none. It took her a year to settle down.
Only one factor of social behaviour, in Konrad Lorenz' opinion, was more significant than the rejected female's immediate, intuitive grasp of all those prerogatives to which her new rank entitled her. And that was the immediate and equally intuitive grasp, on the part of every jackdaw, of the new social situation which each now faced. The creature whom all had pecked could now be pecked by none. Her flauntings were unnecessary. ... From the hour of her ascendancy, every jackdaw by oldest instinct knew his new place, and hers. She was Number One.
—Robert Ardrey, African Genesis
Jackdaws have been observed sharing food and objects. The active giving of food is rare in primates, and in birds is found mainly in the context of parental care and courtship. Jackdaws show much higher levels of active giving than documented for chimpanzees. The function of this behaviour is not fully understood, although it has been found to be compatible with hypotheses of mutualism, reciprocity and harassment avoidance.
Occasionally the flock makes 'mercy killings', in which a sick or injured bird is mobbed until it is killed...
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