Such is the speed of flighting fowl, such their keenness of vision and instant perception of danger, that but a momentary point of time--say the eighth of a second--is available fully to exploit each chance. Should the gunner rise too quick, the ducks are beyond the most effective range; yet within a space not to be measured by figures or words, they will have detected the fraud, and in a flash have scattered, shooting vertically upwards like a bunch of sky-rockets.
Two features in the life-history of the duck-kind become apparent. The first points to the probability that adults pair for life, and that the mated couples keep together all winter even when forming component units in a crowd. For when an adult female is shot from the midst of a pack, the male will almost invariably accompany her in her fall to the very surface of the water, and will afterwards circle around, piping disconsolately, and even return again and again in search of his lost partner. This applies chiefly to wigeon, but we have frequently observed the same trait in pintail and occasionally in other species. It is only the drakes that display this constancy; a bereaved female continues her flight unheeding.
The feature is most conspicuous when awaiting ducks at their feeding-grounds (_comederos_), but it also occurs when shooting on their flight-lines (_correderos_) between distant points.
The second singular habit is the custom, particularly among wigeon, to form what are termed in Spanish _magañonas_--little groups of four to a dozen birds consisting of a single female with a bevy of males in attendance, flying aimlessly hither and thither in a compact mass, the drakes constantly calling and the one female twisting and turning in all directions as though to avoid their attentions. The _magañonas_ appear blind to all sense of danger, and will pass within easy range even though a gunner be fully exposed. Not only this, but a first shot may easily account for half-a-dozen, and should the hen be among the fallen, the survivors will come round again and again in search of her. We have known whole _magañonas_ to be secured within a few minutes.
Other species also form _magañonas_, but more rarely and never in so conspicuous a manner as the wigeon. The habit certainly springs from what we have elsewhere termed a "pseudo-erotic" instinct (see _Bird-life of the Borders_, 2nd ed., pp. 208, 234-5), and is probably the first pairing of birds which have just then reached full maturity.