Wildlife

Tiny Tags Track Hummingbirds

February 9, 2009
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By Dennis Newman

For the first time, researchers at Oregon State University have developed a tracking device that’s so small, it can be attached to a hummingbird.

What’s at stake here is not just tiny technology, but rather serious science to find the cause, or causes, of the world’s pollination crisis.


Green Hermit Hummingbird with transmitter held on by non-toxic eyelash glue.
Courtesy Oregon State University

When we look at pollination, we usually start with bees. But bees are still too small to track individually. So the scientists at OSU decided to think bigger and found a way to track hummingbirds, another important pollinator of the world’s plants and forests.

Working in Costa Rica, they followed the Green Hermit Hummingbird on its trips through the rain forest. What they discovered is that the bird will do just about anything to avoid flying through open areas, even if that means taking an extra long route.

If there’s an island of forest surrounded by open fields, the hummingbirds don’t show up. And without pollinators, these forest islands will find it harder to survive over the long term.

“It’s been widely observed in many studies that we’re seeing a global decline in both pollinators and plant diversity, to the point that many ecologists are calling it a crisis,” says Matthew Betts, an OSU assistant professor. “It’s less clear exactly what is causing this. But it’s a serious concern, since 70-80 percent of all plants are pollinated by animals.”

So far, this is just a small piece of the puzzle of the pollination crisis. The researchers don’t know if pollinators in temperate zones also go out of their way to avoid certain areas. But in general, they say, most animals prefer having these natural connected zones.

According to Betts, “If we get to the point where almost all patches of forests are fragmented, it’s possible that could completely disrupt forest plant ecosystems”.

The study will be published soon in the journal, Biology Letters.

Who Killed The Sea Lions At Bonneville Dam?

February 5, 2009
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By Dennis Newman

One of the strangest stories from last year was the death of six sea lions that were accidentally trapped at Bonneville Dam.

The sea lions were stuck in the traps, unmonitored, for several hours. And by the time someone showed up to check on them, they were all dead.

So who or what killed them?? A investigation by NOAA Fisheries says it was a fluke accident.


Courtesy: NOAA

The trapping was part of a federally approved plan to reduce the numbers of sea lions who camped out at Bonneville Dam to feast on salmon.

(See our earlier story: Salmon Hungry Sea Lions Put On Notice.)

The idea was to capture the worst offenders, the sea lions who ate the most salmon. After capture, officials would try to find new places for them to live, such as zoos or aquariums. Some of the sea lions who were captured early on were sent to Texas and California. But for sea lions that couldn’t find a home, the plan was to put them to death.

Here’s what happened to these six, according to NOAA.

On May 4, six sea lions were in two traps when the doors slammed shut on them. NOAA’s investigation rules out human causes. It says there’s no evidence of human tampering with the traps, or a human mistake that caused the doors to close by accident.

The investigation concludes the doors were jarred closed, probably by rapidly changing river levels, movements by the sea lions, or that the doors’ trip lines became entangled.

The sea lions were stuck there for several hours and without access to the cold waters of the Columbia River, they died from becoming overheated. NOAA says stress may have played a role, too.

Despite the rocky start to the program, State and Federal officials plan to start capturing sea lions again on March 1st. That’s about the time salmon hungry sea lions return to Bonneville Dam for the spring runs.

Federal courts have ruled against animal rights groups that wanted to stop the capture and kill program. In 2007, it’s estimated the sea lions ate about 4% of the salmon trying to pass by the dam.