Researchers at a fossil dig near Aspen have found more than 1,000 fossils.Excavation began at the site last fall after a bulldozer operator uncovered a bone while working on an expansion of Ziegler Reservoir. Work stopped for the winter, but resumed in mid-May.Experts and volunteers from the Denver Museum of Nature & Science said they accelerated their digging effort this week as they reach the halfway point in the seven-week project to remove Ice Age fossils from Ziegler Reservoir near Snowmass Village."Our goal is to remove 50 percent of the bones by the end of this week," said Dr. Kirk Johnson, the leader of the Museums excavation team and vice president of the Research and Collections Division. "We worked closely with engineers who staked out the exact locations to dig and expose the ancient lake bottom, where most of the fossils are located. The landscape is changing daily as we pull out tons of dirt and incredible numbers of fossils."Five Aspen-area volunteers and 10 additional people from Denver have joined the onsite crew of more than 40 people who are digging at an aggressive pace with the help of two excavators, two track hoes and additional machines, officials with the DMNS said."Every time we're here, we find more amazing things," said Johnson. "Everything in this lake is older than 50,000 years and younger than 150,000 years old. It's a complete rock pile bone bed."More than 1,000 fossils have been uncovered since digging resumed on May 15, including 15 jacketed fossils of mastodon skulls and pelvises that each weigh 300 to 700 pounds and are the size of a kitchen stove. A team of 10 individuals is cleaning, wrapping, and processing the fossils to prepare them for conservation and research back at the Museum in Denver.On July 1, the site will be handed back over to the water district and work on the expanded reservoir will be completed. However, a small excavation crew will remain onsite.Get the latest on the project on the Denver Museum of Nature & Science's Snowmastodon Project website.