Saturday, February 20, 2016

Amazon Basin Freshwater Connectivity : What Dams Mean for Animals and People

Poetry magazine asked Jan. 2016 issue contributors to tell them what we have been reading. I wrote this for them. Read this post on Poetry Magazine's website here

I’ve been reading the World Wildlife Fund’s April 2015 scientific report, “State of the Amazon: Freshwater Connectivity and Ecosystem Health.” First of all, it’s amazing to learn that, in rivers with flood pulses that raise water levels, Amazonian fish don’t stay in the river channel. When rainfall and seasonal pulses flood adjacent riparian areas, fish roam into these areas, avoiding predators, seeking resources unavailable in the river, including plant detritus and seeds in nutrient-rich water. They also find nesting and egg-laying areas. Scientists call this “lateral connectivity.” In addition to fish that boost survival rates as they migrate to floodplain resources, other creatures depend on floodplains: pink-nosed and other dolphins, giant turtles, caimans, and otters. Terrestrial animals use riparian areas as migration corridors, including jaguars, tapirs, and peccaries.

However, due to an unprecedented rise in development in the Amazon in the last 5-10 years—primarily dam construction, and also mining, cattle ranching, and agriculture—these freshwater ecosystems are being altered, and with them, the aquatic animals’ abilities to travel between rivers and surrounding riparian areas. In the Upper Xingu River Basin (Brazil) alone, there are 10,000 small dams, 1 every 4 miles. The created water reservoirs change water quality—temperature and sediment level upstream and downstream, and alter water discharge levels (which correlates with decreased rainfall). Where river sediment grains are larger, as the giant Amazon river turtle and yellow-spotted side-neck turtle nest, their eggs’ survival rates have decreased.

In Brazil’s share of the Amazon Basin alone, there are 138 operational, 16 under-construction, and 221 planned large dams—each of which involves removing from their river land tens of thousands of indigenous and traditional river peoples.

In June 2016, when I go to the Tapajos River basin, I will observe this up close. I will post updates here!

As for poetry, I recently finished reading Multitudinous Heart: Selected Poems by Carlos Drummond de Andrade, translated by Richard Zenith.

Read my post on Poetry Magazine's website here