Sunday, March 17, 2013

King Whale-head, Part III

Despite its solitary and quiet lifestyle, the shoebill prefers flat, open areas of wetland, rather than papyrus-choked waterways or covered areas. Any foliage overhead would cause major problems when the shoebill takes off.  Their preferred habitat is wetland with a majority of papyrus, though it avoids all-papyrus wetlands. They are often found perched on floating vegetation near wide waterways. But in stagnant water, there is no current to shape these channels, which criss-cross wetlands of floating plants like city streets.

Typical shoebill turf. Photograph by Jnissa, from Flickr.
These waterways are not formed by currents; rather, they are basically plowed clear by the movement of large wetlands-dwelling mammals. In Africa, this means the elephant and the hippopotamus. The wanderings of these behemoths create the perfect fishing spots for shoebills, and the stirrings of these mammals also causes creatures to rise to the surface.

The shoebill, in turn, doesn’t reciprocate the favor. The hippos and elephants aren’t exactly aware that they’re creating shoebill habitat, and the shoebills don’t have much in their biology to return. It’s a bit of commensalism in action. Though their feeding is greatly benefited by the movement of large mammals, their breeding behavior is very private.

The nest of the shoebill is something I would love to see for myself: a 3m (~10ft) wide mat of floating vegetation amidst isolated tall grasses and sedges. Although the nest is extremely wide, it apparently does not support the weight of a human, which is good, because we don’t need to be living on shoebill nests. The chicks do not hatch with the characteristic bill of their parents; this only begins to grow rapidly after a month. Although up to three eggs are laid, only one chick will survive to leave the nest.
A shoebill feeding its chick. The chick's bill has yet to grow to such ridiculous proportions.
It is the strongest, usually the first-born, is the one who usually lives to maturity: they will bully the other chicks, steal food, and even push them out of the nest. This trend of extreme sibling rivalry can be found in other species of birds as well. While it may seem cruel to us, it ensures that the one chick who survives is the genetically fittest to sire the next generation.
A fledgling shoebill. Judging by that crazed look on its face, I'd say it just committed fratricide. 
We may think that Mommy and Daddy Shoebill are uncaring parents for allowing this to happen. Quite the contrary; they are dedicated parents, and even fill their bills with water to bring to their chicks when the sun is beating down.
A shoebill brings water to its young chick, and apparently misses its target.
The shoebill is a charismatic and incredibly unique bird, and one that should be protected and treasured as much as possible. It is truly an evolutionary oddity, arising mysteriously somewhere in the depths of time, and it has filled such a specific niche that it has, apparently, changed very little in millions of years. They are behaviorally very curious, very caring, and I believe that they will never cease to amaze ornithologists across the globe.

A shoebill towers over all other birds in its habitat. Photograph by Stttijn, from Flickr.

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