Endangered Elephants Are Main Seed Dispersers of Congo's Forest: Study

Forest elephants in Kenya (Meisjesanne via Flickr)

Shy and reclusive, the forest elephants of Congo, Central Africa are being pushed to the brink of extinction by the loss of habitat and illegal poaching for the ivory and bushmeat trades. What may not be apparent is the fact that if the forest elephants disappear - the forests might vanish as well.

It's because indigenous plant species may rely heavily on forest elephants to ensure that their seeds are spread far and wide — and in fact, that's what a new study of seed dispersal has found - that forest elephants may be responsible for spreading and planting more seeds in the Congo than any other species or genus.Along with his team, Dr. Stephen Blake of the Max Planck Institute for Ornithology found that forest elephants, considered a smaller subspecies of the more well-known savannah-dwelling African elephants, consumed more than 96 species of plant seeds and can carry them as far as 57 kilometers (35 miles) from the point of origin. The study did not take into account seeds smaller than a centimeter, even though seeds of this size were estimated to number in the hundreds and thousands in the dung piles studied.

Proof is in the dung
Blake and his team studied no less than 855 dung piles and used GPS collars to track the elephants. The rate at which seeds are passed through the digestive system depends on the size of the seeds — ranging from 24 hours for small seeds and 72 hours for larger ones. The team found that the elephants moved anywhere from 24 kilometres before passing small seeds and 57 kilometers for larger-sized seeds, concluding that "long-distance movements are not rare events for forest elephants, but occur on a daily basis."

The study concluded that forest elephants surpassed all other species — including birds and primates — in their ability to disperse plant seeds. Even their savannah cousins cannot compare, as forest elephants differ from their savannah cousins particularly in their diet: they graze less, and eat large quantities of fruit found in the forest.

This means that without forest elephants — who are currently facing unprecedented threats to their survival — the tropical forests will not be the same.

"Hunting for ivory is the major threat facing forest elephants, which is facilitated by logging road development. The illegal ivory market is booming," says Blake. "We are witnessing the annihilation of the forest elephant at a time when the popular dogma is that African elephants are no longer threatened."

"Living in fear"
A recent survey of Congo's elephants has clearly highlighted their unmistakable plight, showing an 80 percent decline in 50 years. Another study conducted last year by Blake also found that elephants showed an aversion to roads, as they bring poachers and death. From Innovations Report:

"Forest elephants are basically living in fear of their lives in prisons created by roads. They are roaming around the woods like frightened mice rather than tranquil formidable giants of their forest realm," said Dr. Stephen Blake, the study's lead author. "Forest elephants are under siege with all of the graphic images that go with it — increasing the likelihood of fear, starvation, disease, massive stress, infighting, and social disruption."

"A radically different place" without forest elephants
In any case, it seems that changes to the forest have reached a critical point, and only drastic conservation and regulatory measures will have some effect in saving the elephants (and the forests) from total annihilation.

"An elephant poaching pygmy friend told me years ago that if the elephants go, the forest will die," Blake continues. "It might not be quite as dramatic as this, but the loss of forest elephants on the functionality of central African forests might be comparable to the loss of all vehicles for the functionality of Manhattan. It would be a radically different place."

More on Endangered Elephants
Killing Rare Animals Funds Terror
Elephant Dung Paper and Paper-Products
A Picture is Worth... Elephant Having Fun
Long-Term Memory Gives Elephants an Edge Against Climate Change
Roads Bring Death and Fear to Forest Elephants (Innovations Report)

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