Wednesday, 10 April 2013
More evidence that over-hunting changes forest structure
A new study published in the Proceedings of the Royal Soc. B. this month adds more weight to the growing body of evidence that removing seed dispersers from rainforests affects plant community structure (see Harrison et al., 2013, reported in Blogpost “Over-hunting causes reduction in tree diversity over time” and Beaune et al., 2013, reported in Blogpost “Elephant-dispersed trees suffer population declines when elephants are hunted out”).
Effiom et al. (2013) compared paired sites with low and high hunting pressure in southeastern Nigeria. Small and large primates (including drills, chimps and gorillas), were severely reduced in the hunted sites compared to protected, whereas ungulates and rodents were more abundant. While both hunted and protected sites had similar mature tree communities dominated by primate-dispersed species, this was not the case among the seedling communities. Primate dispersed seedling densities were significantly lower in hunted sites than protected, and hunted sites were dominated by seedling species with other dispersal modes. The authors conclude that the changes observed in the current seedling generation support the hypothesis that a forest empty of large seed dispersers is likely to face drastic changes in future tree community structure.
Effiom EO, Nunez-Iturri G, Smith HG, Ottosson U, Olsson O (2013) Bushmeat hunting changes regeneration of African rainforests. Proceedings of the Royal Society B: 280 (1759): 20130246.