It’s now been one week since I got home, so it seems like a good idea to finish off this blog exercise with a brief retrospective. After all, I made a point of setting out what I was anticipating and, as predicted, all that imagery has been expunged.
Two major points pop quickly to mind. First, the scientific side of the trip was quite a bit short of what I’d hoped, but (and this is key) more valuable than it might seem. Second, the cultural experience was far more impactful than expected. I’ll expand each of these in turn.
First, the science. Of the two stated goals, one was quickly abandoned when it became clear that finding shoebill nests would be both difficult and prohibitively dangerous. The rising waters of the late rainy season expanded suitable habitat throughout the Nile basin and the tractless expanse of bulrush/papyrus marshes would have required searching by canoe/foot, neither an inviting option with crocodiles, Cape buffalo, and hippos in such abundance. In any case, my desire to park GoPro cameras where they could videotape siblicide at the nest was a secondary goal, so that was dropped early on.
The main objective, seeing/filming hunting behavior, produced scant results. Again, the high water seems to have dispersed the small population of shoebills such that they were simply not present in the primary area of focus (the “Delta” region where the Victoria Nile approaches Lake Albert). To the north of Pakuba Lodge, we did find what was probably a mated pair near the Pakwach Bridge and we observed both partners hunting where we could observe. But they were often elsewhere, so we saw and filmed a meager total of just five strikes and two captures of prey.
Even so, I learned enough about shoebill hunting to be very encouraged about a return trip for the serious data-collection phase of the study. The most compelling clue came from measuring the water turbidity with a Secchi disk and documenting that the water from which shoebills capture prey is pretty much opaque! It is also stagnant, shallow, and very warm. The two fish we saw captured were “Cornish jacks,” a weakly electric species of the family Mormyridae. These are known to find their own prey by creating an electrical field around their bodies and monitoring it for distortions that inform about objects, moving and stationary, nearby. That is, they can operate essentially without vision, underscoring the significance of the habitat’s opacity. This all suggests that shoebills often (usually? always?) strike at prey they cannot see, thus rely on a degree of guesswork about where the target is located during the attack. And that, in turn, conforms neatly to the hypothesis that the laterally expanded “shoe”-bill is an adaptation for poor aim, a feature that evolved to improve capture success in these odd conditions. In that light, we also noted that various other fish-eating birds, some of them fellow waders (herons, storks, etc.) and some of them plunge-fishers (kingfishers, fish eagles, ospreys), that were present in the same habitats were NOT trying to catch fish where the water was so turbid. An attractive line of argument is that mutations that produced wider bills tended to increase in the shoebill-ancestor's populations because those wider bills enabled this one bird to exploit a prey supply that is unavailable to "regular" fish-eating birds. (There are a couple stork species that can hunt in such waters because they hunt by feel ("tacto-locating"). Spoonbills can do that, too.
In short, we learned enough about shoebills to understand that all we really need now is a lot more field data of hunting behavior, which we propose to collect about 15 months hence, during the DRY SEASON (when the habitat will be much-reduced and shoebills more easily observed!). So, our 2022 effort is now officially dubbed a Pilot Study. And while I think the riddle of the shoebill’s bill is better-understood, I’m old enough to distrust my hunches: the birds themselves will have to provide a satisfying explanation.
Over on the cultural side of my month in Uganda, I hardly know where to start. All the people I met were delightful. And I’ve done enough travel in developing nations that I was unsurprised by the poverty per se, but this time it hit home with some force, largely because of working from a UWA rangers’ boat as they patiently tried to enforce the fishing regulations. I’ve done fieldwork in rural Venezuela, a small Mexican fishing village, etc., where I was surrounded by people with serious economic struggles, but the context here illuminated conflict between burgeoning human populations and wild animal populations in a way that was more immediate, more dramatic for me.
In a sense, the 'biology' and 'anthropology' aspects of my month are intertwined, which is not usually the case in my work. In general, my kind of field biology is “basic” science, not “applied.” That is, I typically contemplate aspects of animal behavior that may seem absurdly esoteric: why do baby egrets kill their close kin?…why do birds mate more monogamously than other vertebrates?…why do some herons have white plumages?…why does the shoebill looks so goofy?…what information does a nestling bird convey to its parents when "begging" for food, that it is needy (or the opposite, that it is superior?…why some birds nest in dense colonies?…etc. Such questions may strike some as a 'luxury' sort of curiosity.
But MOST field biology is done with more practical concerns, like how many whooping cranes and California condors are left and how can we prevent their extinction?…or how does the use of pesticides on insect populations affect grain yields, malaria infections?...etc. Unsurprisingly, the great majority of research money goes for such applied work. Indeed, most life science research support goes straight into human medicine and public health, as it should. Those of us fortunate enough to live in Developed Nations enjoy a lifespan that is triple what it was before the discovery of Germ Theory in the early 19th Century.
This standard dichotomy between basic and applied science may not work so well for our shoebill study. Whereas I am chiefly interested in the functional (ecological) significance of the bill’s size/shape, my partner Kenneth is motivated more by boosting the tourism industry of Uganda in such a way as to create enriched economic opportunities for the Bantu and Luo peoples living near Murchison Falls National Park. That is, if our work results in making shoebills more interesting to the international tourist market, the park could become a more attractive destination for bird enthusiasts. Plausibly creating more jobs and expanding the local economy in ways that may reduce the fishing pressure on dwindling stocks of Tilapia and other fishes. There will be less desperate need for people to sneak into the park and set wire snares for “bush meat” as their only means of feeding their families.
I will not live to see major change on that scale, but it’s a comforting thought, nonetheless, to imagine that child-like curiosity about an odd bit of avian anatomy might be used to help people a bit. Rural Uganda's bigger problems will require much more durable long-term solutions from better education (and better government) and curbing human population growth. My paltry reflections on these problems are worth rather little, but this friendly Martian would like to play a small supporting role in the bigger struggle. For that, the first step is simply to become more aware...
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