On behalf of African Parks, a research team is studying the shoebill population in the Bangweulu Wetlands since April 2011.
Currently, Dr. Ralf Mullers from the FitzPatrick Institute of African Ornithology (PFIAO) at the University of Cape Town is responsible for the research project, assisted by Brighton and Elijah Mofya, two local guys with unequalled knowledge about the swamps and its inhabitants, human and animals alike.
The Bangweulu Wetlands are located in north-eastern Zambia and consist of floodplains, swamps and grassy woodlands. The system is fed by 17 rivers, amongst which the Chambeshi, Luapula, Lukulu and Lulimala rivers, but drained only by the Luapula river. The area is a Ramsar site and an Important Bird Area. Recently, the Bangweulu Wetlands have received increased protection through the Bangweulu Wetlands Project and the creation of the 2900 km2 Chikuni Community Partnership Park (CCPP) within the Game Management Area. Humans exploit the area for fisheries in the swamps and cultivation at the periphery of the park. Many permanent and temporary settlements are built in the higher parts of the swamps and fishing pressure is heavy year round. The human population that depends on the productivity of the Bangweulu ecosystem is estimated at about 50 000 individuals.
The aim of the shoebill research project is to understand the best way to manage the Bangweulu Wetlands to ensure the conservation of the shoebills (Balaeniceps rex). Particular attention is paid to understanding whether human activities – especially through over-fishing or disturbance – could be a limiting factor for the long term viability of the shoebill population. The research project combines some standard methods of data collection with high-tech ways of looking at the movements of shoebills. We go into the field with binoculars, pencil and notebook and good hopes to find shoebills, but we also mounted GPS transmitters on several shoebills, which provide us with hourly GPS positions of these birds. We have several research interests, which we will explain shortly on this page.
Shoebill distribution One of the important objectives of this project is to generate reliable estimates of the shoebill population in the Bangweulu Wetlands. In order to achieve this, we need to understand where the shoebills are in relation to suitable habitats and human presence. Shoebills are quite elusive and hard to find. Therefore we conducted some aerial surveys to find out where the shoebills prefer to hang out and forage. These observations will be used for spatial modelling, helping us to understand the relationships between shoebill occurrence, habitat quality and human activities. Besides looking at population level, we are also interested in the distribution patterns of individual shoebills. GPS transmitters (70 gr solar powered, MicroWave Telemetry Inc., USA) are being deployed on shoebills and these provide information on individual home ranges, seasonal distribution patterns and possibly whether there is any migration between different populations of shoebills. The only problem with using GPS transmitters is that we have to catch shoebills, but until now we have been outsmarted by the adults. We did manage, however, to deploy three chicks with transmitters and the devices provide valuable information on their whereabouts in the swamps.
This part of the research is done like in the days of Dr. Livingstone; paddling with our boat into the swamps, looking for shoebills and when we find one, we take out our binoculars, pencil and paper and start recording its behaviour. By studying the foraging behaviour of shoebills, we aim to understand a few aspects of their general feeding ecology; 1) activity budgets, 2) prey type and size, 3) habitat use, and 4) seasonal differences in foraging behaviour. Lots of patience is needed for these observations, as shoebills mainly stare into the vegetation, waiting for catfish to gulp in some air at the water surface. So far we collected about 140 hours of observations. Most of that time, 116 hours to be precise, was spent by the researcher staring at a bird that was staring into the vegetation or preening itself. Not the most exciting observations, but we had to be focussed, because if a shoebill strikes, it will do it fast and with vigour. It will throw itself forwards, almost loosing balance, flapping with its wings and hoping that in between the grasses and other vegetation it caught, there will be a fish as well. Shoebills mainly feed on catfish, but every now and then it will catch a snake or smaller prey species like frogs.
The main objective with studying the nesting behaviour of shoebills is to establish an estimate of breeding success and possibly a total number of breeding pairs in the Bangweulu. The latter will be hard to derive, as the Bangweulu is a vast and often inaccessible wetlands. Shoebills lay 2 eggs, which both hatch after about 45 days. The two chicks survive together for a few days or weeks, but then typically the oldest chick will outcompete its younger sibling and remain in the nest by itself. Even though this seems harsh, siblicide is occurring throughout the animal kingdom and is a way of optimizing breeding success. The chick will leave the nest after about 95 days, but will remain with its parents for another few months in order to learn to forage for itself.
With the information collected from the aerial surveys and from local fishermen, we visit nest sites when and where possible. When arriving at a nest site, we measure chicks for their growth and make behavioural observations. For the behavioural observations we install camera traps (Trophy Camera Camo, Bushnell, U.S.A) near the nest. The camera traps are set to make a picture when detecting movements and they prove to be a useful tool for our observations. In 2012 we monitored 4 nests, from which 3 chicks fledged successfully. One chick disappeared from the nest and although it was not entirely clear from the pictures taken by the camera trap, we believe that the chicks was taken by a predator, most likely a water monitor or a python. Two of these chicks have been deployed with a GPS transmitter, and provide us with important information on their distribution.
Besides the data collected as described above, we furthermore collect data on habitat descriptions and water levels, and we conduct bird counts in two transects near Chikuni. These data will be used for a general understanding about seasonal patterns in changes in the wetlands. The water levels are measured on a daily basis, whereas the bird counts are done once per month.