Early next morning (April 11th) we started to explore the wooded swamps called La Rocina de la Madre—a nasty place to work: consisting of thousands of grassy tussocks, each surrounded by bog, in some places moderately firm and safe, in others, apparently similar, deep and dangerous, and everywhere swarming with leeches. In the centre of the open marsh, surrounded by quaking-bog and a dense growth of aquatic vegetation, rose a thick clump of low trees, whose snake-like roots were growing out of the black and stagnant water. These trees were occupied, some laden, with hundreds of stick-built nests, the abodes of the southern herons some of which we have already mentioned—Egrets, Squaccos, Buff-backs, Night-Herons, and the like: but nearly all this group nest very late (in June), and the colony was at this season tenantless. In subsequent years we have obtained in these wooded swamps the eggs of all the European herons: though it is not every summer that they repair thither to breed. In very dry seasons none are to be seen, but after a rainy spring, these heron-colonies of the marisma are indeed a wondrous sight—an almost sufficing reward for enduring the heat, the languor-laden miasmas, and the fury of the myriad mosquitos and leeches which in summer infest these remote marshy regions.
Climbing across the gnarled tree-roots to the other end of the thicket, we found a larger nest, and just as we emerged on the open, its owner, a female Booted Eagle, passed within reach as she slowly quartered the marsh, and fell to a charge of No. 2. This small, but compact and handsome species, has been confounded with the Rough-legged Buzzard; but no one who has seen Aquila pennata on the wing could mistake it for anything but an eagle. The nest proved empty, after a difficult climb up a briar-entwined trunk: but on the following day we found another, in the first fork of a big cork-tree, containing one white egg. Three is the full number laid by the Booted Eagle.
In another part of the wood was a nesting colony of the Black Kite (Milvus migrans), several of which soared high overhead. These birds hardly commence domestic duties in earnest before May, but after some trouble I succeeded in shooting a fine adult: also a pair of Purple Herons, of which we found three nests, and a single Roller (Coracias garrulus) from her nest in a broken stump, which contained one egg. After this we were obliged to beat a retreat, for the swarming hordes of leeches had developed so strong a taste for the bare legs of our two men that a return to terra firma became necessary.
The whole region for many a league around Rocío is one dead-flat plain—dry scrubby brushwood or stagnant marsh and marisma. To the northward, in the farthest distance are discernible the dim blue outspurs of the Sierra de Aracena; but beyond its charms to naturalist or sportsman, the district has few other attractions. After spending ten days in the wilderness, we set our faces homewards, and were not sorry on the third evening, after re-traversing the waste, to sight once more the white towers and lustred domes of San Lucar de Barameda.
CHAPTER VII.
THE BÆTICAN WILDERNESS.
SPRING NOTES OF BIRD-LIFE AND NATURAL HISTORY IN THE MARISMA.
Part II.—May.
