Ecology of African Rainforests
Many scientific studies in African rainforests have been short-term and expedition oriented. In collaboration with Dr. Colin Chapman, we are tying to counter this bias by designing research programs to target seasonal, interannual, and long-term change (natural and anthropogenically-induced) in African rainforests, and in the lakes, rivers, and wetlands that are integral components of these systems. As examples of contributions in this area, we have explored the importance of climate change to fruiting phenology (Chapman et al. 2004, Chapman et al. In press), identified potential mechanisms limiting succession and restoration of disturbed forests (Chapman et al., 2003, Paul et al. 2004), validated the protein-fiber model for predicting primate abundance (Chapman et al. 2002, Chapman and Chapman 2002), and contributed unique data on seasonal and longer-term variation in dissolved oxygen dynamics (Chapman et al. 1998, 2000, Chapman 2001).
The Role of Developmental Plasticity in the Biological Control of Schistosomiasis by a Facultative Molluscivore
Schistosomiasis, a parasitic disease caused by trematode worms (flukes) affects millions of people world-wide. The intermediate hosts of human schistosomes are freshwater snails, and biological control of snails using molluscivorous fish has been recurring theme in control programs for schistosomiasis. However, the effectiveness of this control method is highly variable. For the facultative molluscivore Astatoreochromis alluaudi (an East African cichlid) field trials have indicated initial success, but not necessarily over the long term (see review in Slootweg et al. 1994, Rev. Fish Biol. Fish. 4:67). Astatoreochromis alluaudi is well known for a high degree of plasticity in the pharyngeal jaw apparatus and associated muscles in response to the nature of its prey base (hard vs. soft prey), in addition to plasticity in associated structural characters (Chapman et al. In press). In collaboration with Brian Allan ( University of Illinois at Urbana-Champaign), studies are being undertaken to explore whether competitive interactions among haplochromine cichlids increase the predation rate of Astatoreochromis alluaudi on the snail vectors. This is particularly relevant in the Lake Victoria basin, where introduction of the predatory Nile perch resulted in a dramatic decline in the richness and abundance of haplochromine cichlids.
Fish Conservation in Canada’s Northern Boreal Forest
Fish communities in this most extensive boreal wilderness area of Canada represent important biodiversity banks and are exploited both for recreation and subsistence. Yet, our understanding of the basic biology of these fish populations and current threats is limited and constrains effective conservation and management of these populations. In collaboration with Wildlife Conservation Society Canada, we are conducting a project to review the biology and ecology of selected fish species and communities (focusing on species important for commercial, subsistence, and recreation, species at risk, and rare communities); analyze and discuss conservation considerations and review known, likely, or potential impacts to these species and communities from development-associated threats; and develop a suite of recommendations for: incorporating freshwater fish considerations into conservation planning with discussion of relevant tools, monitoring and management, and regional research needs and priorities.