There is a bird curator I know who has a special passion for storks. Not just, the storks, mind you, but their closest relatives as well, all of which used to lumped together as one taxonomic group before the splitter came along. This group consists not only of the storks but the ibises, shoebills, pelicans, and flamingos as well - this curator loved them all, and if he had his way, he would have had a zoo that was full of these birds and no others.
There was one particular member of the branch of this avian family tree that he always swore up and down that he would never have in his zoo, one which he vocally criticized whenever he heard about in zoos. And bird, ironically, is one of the most sought after, rarely-exhibited of zoo birds - the shoebill.
The shoebill, sometimes called the shoebill stork (though, again, under the new taxonomy, it's closer to the pelicans than to the storks) is a massive, bizarre-looking bird from Central Africa. It's a tall, rather homely looking bird, with a beak like a big wooden clog and eyes that look like they belong to a serial killer. Those eyes and that beak are a bit more striking than they'd be in other species of bird, because in a shoebill those eyes are going to be roughly on level with your eyes, the beak with your face. They're a strange, big, fascinatingly ugly bird. It's no wonder that zoos have loved them for decades.
While it has been accomplished, however, shoebills don't breed reliably in zoos, with only a few institutions having had luck hatching them out. As a result, only a small number of these birds are found in American zoos, and that number is expected to continue to decline until they phase out. I last saw the species at the San Diego Zoo Safari Park in 2016, and am not sure when or if I'll see one again. Any attempt to re-establish the species in the US will be reliant upon wild imports, with no guarantee of successful breeding resulting in a stable population. It's this fact which led the curator to be so adamantly opposed to the keeping of the species in the future. Removal of animals from the wild just to fill zoo exhibits is something that we think of as being left in the past.
The thing is, though... shoebills do a great job of removing themselves from the wild.
Shoebill parents produce 1-3 eggs, but generally only one chick survives - the oldest of the clutch. The death of the younger sibling(s) is a result of a combination of neglect from the parents and direct violence from the older sibling. This phenomena, which is seen in many birds, ranging from grackles to boobies to raptors, is called siblicide, or Cainism, after the Biblical first murderer. Some species are facultative cainists, in which siblings could live together, but resort to this dark behavior based on challenging environmental conditions, such as drought not providing enough food. Others are obligate cainists - one sibling almost always ends of up killing the others. Even in good years, it's rare for more than one shoebill chick to fledge.
In situations like this, I sometimes wonder, what's the harm in zoos stepping in? If a certain number of shoebill eggs/chicks are laid/hatched but destined to die anyway, does it really harm the natural world for a few to be removed each year to be raised in zoos? They were just going to die anyway. And if those birds grow up in zoos and, despite best efforts, don't breed, and we can't build a sustainable shoebill population, does that matter, if we're able to sustainably harvest a few eggs or chicks now and then to replenish zoos? Shoebills are long-lived birds, and especially if only a few zoos were involved, the number of eggs or chicks taken would be minimal. Presumably, if the chicks slated to die could be polled, a life in a zoo aviary would seem preferable to being bludgeoned to death by your older brother or sister, or pushed out of the nest by your parents.
Anything that proves to be detrimental to the wild population is non-negotiable, in my opinion, and it is true that there has been harassment or wild shoebills by folks raiding the nests to sell birds to collectors. But if it could be done in a safe, sustainable manner, I admit I see no harm.
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