Seeds of Change

Bushmeat hunting in Africa is changing not just animal communities but the forest itself, scientists say in Proceedings of the Royal Society B.

Many large animals are threatened in Africa, Asia, and South America, partly because of people’s rising appetite for meat and the increasing ease of delivering carcasses to cities. The study authors wanted to find out how the disappearance of animals affected the plants in the forest. After all, many large primates spread the seeds of fruit-bearing trees. What happens to those trees when the primates are gone?

The team studied pairs of sites in three areas in Nigeria. Each pair included a protected site and a site where protection from hunting was lax. At each site, the researchers surveyed animals such as gorillas, chimpanzees, squirrels, and porcupines, as well as young and mature trees.

Not surprisingly, the protected sites had more than twice as many primate groups as the unprotected sites. While mature trees were similar in both types of forests, the team saw a stark difference in the seedlings.

Seedlings of trees that rely on primates to spread their seeds were more than twice as dense in the protected areas. In the hunted areas, seedlings had shifted toward plant species that depend on other types of animals or on non-biological methods, such as wind, for seed dispersal. The authors conclude that “a forest empty of large seed dispersers is likely to face drastic changes in tree community over the next few tree generations.” Roberta Kwok | 19 March 2013

Source: Effiom, E.O. et al. 2013. Bushmeat hunting changes regeneration of African rainforests. Proceedings of the Royal Society B. doi: 10.1098/rspb.2013.0246.

Image © Brendan van Son |