Six Large-Mammal Migrations Now Gone - Blocked Routes, Species Extinctions - Mongabay

[hatrack]

Watch any nature documentary and it’s sure to include pulse-pounding footage of large herbivores migrating across African plains, Asian steppe, or the Arctic tundra. The images have become iconic: wildebeest forging a crocodile-inhabited river, caribou breaking through snow fields, Saiga running over tall grass. Despite such images of plenty, migrations are declining across the world, and in six cases have disappeared entirely.

A new study published in Endangered Species Research looked at the state of just these kinds of migrations, focusing on 24 large ungulate species (hoofed animals) known for their migratory patterns. Researchers included some well-known species, such as caribou, American bison, elk, zebra, wildebeest, chiru (or Tibetan antelope), and saiga.

"Conservation science has done a poor job in understanding how migrations work, and as a result many migrations have gone extinct," explains Grant Harris of the Center for Biodiversity and Conservation at the American Museum of Natural History, first author of the paper. "Fencing, for example, blocks migratory routes and reduces migrant's access to forage and water. Migrations can then stop, or be shortened, and animal numbers plummet."

According to the study, all 24 focal species lost migration routes and suffered population declines. Many of these migrations have been little studied. While Africa includes the most large-scale migrations, the authors found that three migrating species had no publications on their population status. In Eurasia half of the migratory species had been largely ignored by science. Six of the focal species either no longer migrated at all or, in a couple cases, no longer survived in the wild: the springbok (Antidorcas marsupialis) used to form some of the world’s largest migrations; the black wildebeest (Connochaetes gnou) was nearly exterminated and has relied on reintroduction efforts; the blesbok (Damaliscus dorcas) is not endangered but no longer migrates; the dwindling kulan (Equus hemionus) of central Asia; the scimitar horned oryx (Oryx dammah) is extinct in the wild, but there are plans for reintroduction; and the extinct quagga (Equus quagga) from southern Africa.

EDIT

http://news.mongabay.com/2009/0603-hance_migration_ungulate.html

[byronius]

1. Thanks, hatrack. Thanks for this post.

You rock.

[amborin]

2. K & R