The following autumn, however, it at once became apparent that the venture was a failure. No wildfowl would tolerate her presence within half-a-mile. No sooner had her low snake-like form crept clear of fringing covert than the broad _lucio_ in front was in seething tumult, every duck within sight had sprung on wing. Naturally we tried every known plan, but all in vain. A system that is effective on the harassed and hard-shot estuaries of England utterly broke down on the desolate marismas of Spain. The apparent explanation is that whereas fowl at home are accustomed to see passing craft of many kinds, and perhaps mistake the low-lying gunboat for a larger vessel far away; here no craft of any sort navigate the marisma, or should the box-shape _cajones_ of native gunners be so classed, they are at once recognised as wholly and solely hostile.[63] One plan remained by which the big gun might be brought to bear upon the larger bodies of fowl: concealing the boat among sedges at some point where ducks had been observed to assemble _within reach_ of such covert. That, however, to begin with, was most uncertain--the only certainty was that enormous drafts on patience would be required; and, after all, it forms no part of the system of wildfowling afloat and lacks the joys and glories of that pursuit. WILD SWANS IN SPAIN Since meeting with four hoopers in February 1891, as recorded in _Wild Spain_, we had neither seen nor heard of wild swans in Southern Spain till February of the present year, 1910, when H.R.H. the Duke of Orleans kindly informed us that he had succeeded in shooting one of a pair met with in his marismas of Villamanrique. It proved to be an adult male of Bewick's swan--the first occurrence of that species that has been recorded in Spain. CHAPTER XXXVIII THE "CORROS," OR MASSING OF WILDFOWL IN SPRING FOR THEIR NORTHERN MIGRATION The withdrawal of the wildfowl at the vernal equinox affords an unequalled scenic display. It forms, moreover, one of those rare revelations of her inner working that Nature but seldom allows to man. Her operations, as a rule, are essentially secretive. A little may be revealed, the bulk must be inferred. Here, for once, a vast revolution is performed in open daylight, _coram populo_--that is, if the authors and a handful of Spanish fowlers be accepted as representative, since no other witness is present at these scenes enacted in remote watery wilderness. Up to mid-February the daily life of the marisma continues as already described. From that date a new movement becomes perceptible--the seasonal redistribution. Daily there withdraw northward bands and detachments counting into thousands apiece. But no vacancy occurs since their places are simultaneously filled by corresponding arrivals from beyond the Mediterranean. It is at this precise epoch that there occurs the phenomenon of which we have spoken.