The Clark Fork Coalition will sponsor a free event Monday to help educate Missoula residents about the connection between osprey and contaminants – specifically mercury – in local river ecosystems.

University of Montana wildlife biology professor Erick Greene will speak at the event at the Hellgate Canyon osprey nest, located near the new Missoula College site, 1301 E. Broadway. The presentation will take place from noon to 1 p.m.

Greene will give an overview of the history of the Clark Fork River, as well as the upstream mining and removal of Milltown Dam. Greene also runs the Montana Osprey Project with Rob Domenech, a leading raptor migration expert, of the Raptor View Research Institute.

The goal of the project, which has been running since the removal of Milltown Dam, is to study the eco-toxicology of local river systems, specifically for heavy metals and mercury. These contaminants show up in osprey, which are the top predator in their food chain.

The Montana Osprey Project tracks osprey along the river, and looks at blood and feather samples to test for toxins. So far, more than 200 osprey chicks have been banded for tracking.

Part of Greene’s talk Monday will focus on what osprey health can tell researchers about overall river health. While researchers have found heavy metals in tested birds to be relatively low, Greene said the amount of mercury in the osprey was “disturbingly high.”

“Most of it is coming out of Flint Creek and the Philipsburg area, where it was used in gold and silver mining to extract the metals from ores,” he said.

Clark Fork Coalition science director Chris Brick will also talk about what the organization is doing to reduce river contaminants in the Clark Fork and its tributaries.

The public is invited to bring binoculars and spotting scopes because the location of the presentation is home to Missoula’s two most famous osprey, Iris and Stanley. For more than six years, Greene’s team has had a high-resolution camera streaming up-close footage of their nest live on the Internet.

Naming the birds has helped to create a personal connection between them and the viewers, Greene said, which he hopes has caused more people to be aware of the potential environmental dangers they face.

“It’s gone viral. It’s been watched by people in countries around the world with millions of hits,” Greene said. “We're just privileged with this camera to watch very intimate aspects of truly wild creatures.”

When Iris and Stanley left last year, however, he wasn't sure they would ever return to their nest. Greene was worried that when they came back, noise and disruption from the construction of Missoula College would cause them to abandon the nest.

Greene worked with University of Montana planners as well as the construction company to mitigate the potential disruption to the birds, and said their response has been great.

“At key periods, the construction company has laid low to minimize the disturbance,” he said. “Now, the birds couldn’t give a hoot. They are basically ignoring bulldozers and trucks and cranes going on right underneath them.”