The Fossil Fish Capital of the World

Over the years Wyoming's Green River Formation has yielded the world's most significant Eocene terrestrial fauna—insects, fishes, reptiles, birds and bats—all magnificently preserved. It is also the world's richest fossil deposit, whose bounty has been harvested for over a hundred years and whose specimens are sold to every rock and mineral trade store in the world. Yet despite this, there are still troubles with poachers and illegal diggers. Where there's money involved, there's crime.

Sketch of Gallinuloides wyomingiensis, one of the very rare Eocene fossil birds from Wyoming. (Bar scale is 10 cm)

The sign outside the town read 'Kemmerer, Fossil Fish Capital of the World'. I had to stop the car and get out to admire the sign, as after all, I am a fossil fish expert. Finally, I'd made my pilgrimage to the world's fossil fish Mecca. I'd offered to drive Steve home when we left Salt Lake City, to give myself an excuse to visit the famous Green River fish sites just west of Kemmerer.

The Green River Formation is a very thick succession of sedimentary rocks representing three ancient lake systems, which existed from about 57 million years ago (the Paleocene Period) through to about 38 million years ago (the late Eocene Period). Most of the fish fossils come from the Fossil Lake Deposit, and these fish are about 49-53 million years old. Other fishes and animals from the Lake Gosiut Deposits are a little younger, dated at around 46-48 million years old. The Lake Unita Deposits don't yield as many fishes but are famous for their fossil mammals, and are well exposed in neighbouring Utah.

Fossil fishes were first discovered in the Kemmerer region back in 1856 by Dr John Evans, a geologist. He sent his first specimens to a well-known palaeontologist, Joseph Leidy, who named it as Clupea humilis, but the name was later changed to Knightia eocenica. Knightia is the most abundant fish fossil in the formation and has been made the official State fossil emblem of Wyoming. By the 1860s large quantities of the fossils were being collected, as railway workers uncovered the rich fossil fish layer and gathered specimens for State geologist Ferdinand Hayden. Hayden gave the fish to palaeontologist Edward Drinker Cope, who eventually went back himself to collect more fishes and write scientific papers describing them.

Since the 1900s a small number of collectors have been responsible for supplying almost all of the world's private and museum collections of Green River fishes. Robert Lee Craig collected fish from the region for over 30 years, starting in 1897. David Haddenham joined Craig in 1918

and, with his sons and grandson, worked the site until about 1970. Carl and Shirley Ulrich began working the region in about 1947. Robert Tynsky and his family began quarrying the fishes in 1970 and, like the Ulrichs, still work there today (Grande 1984).

After dropping Steve in Kemmerer, I drove another 20 km or so to the town of Fossil, Wyoming (with a population of two, according to the rusted sign). The unusual, rounded wooden house that dominates the town is the home of Carl and Shirley Ulrich, who have been working the Green River Shales for fossils for over 50 years. It is situated just opposite the spectacular Fossil Butte National Monument, now a protected site policed by pistol-packing palaeontologist and park ranger Vince Santucci.

On entering the Ulrich house I introduced myself to Shirley, who was minding the fossil gallery. The rest of the film crew had met Carl and Shirley a few days earlier, when they had flown to Kemmerer with Steve and called in at the gallery. Shirley was pleased to meet me, and told me how much she liked having Australians working up at their quarry. (So much so that she extended an invitation to me to tell anyone I knew back home that there was regular work there if they wanted to come over and dig the sites during summer.) The gallery was full of amazing specimens, each one a unique work of nature's art, the essence of what was once a living organism. The fish are almost perfect, their dark, complex skeletons contrasting well with the light, greyish-yellow shales. Some of them are enormous. A large garfish, about 1.5 metres long, formed the gallery's stunning centrepiece. The beauty of Green River fishes, though, is brought out largely by the skill of the preparator. Each preparator, like any other artist, has his own methods and unique skills. Fossil fish aficionados can even identify individual preparators' work.

In the downstairs workshop area Carl Ulrich, swathed in a huge apron, and with magnifying spectacles over his eyes, was intent on his workbench; one hand holding the buzzing drill tip, the other stretched out over a large slab of shale covered in fish fossils. Some of these fishes were cleanly prepped whole skeletons, others were still struggling to emerge from the rock.

'At times it's been hard to scratch a living from the fossils,' he told me in his slow drawl, 'but it's a job I have greatly enjoyed over the years.'

Carl and Shirley are model examples of people who work in the fossil-selling industry. They lease a quarry and, with the help of family and enlisted workers, open it up each summer to quarry out the rich eighteen-inch layer of fossils. Occasionally rare things turn up, such as remains of fossil birds, but more than 99 per cent of what is excavated is run-of-the-mill fish, plants and small insects. All of this material can be prepared and sold without government intervention. In the State of Wyoming, the Board of Land Commissioners lays down the rules and regulations for commercial and scientific permitting. Common invertebrates and five common species of fish can be quarried and sold without review by the Wyoming Geological Survey and without payment of royalties. Rare species such as fossil garfish, rays, bowfins and paddlefish can be sold without review, but the State requires that they be reported and that royalties be paid. All rare and unusual specimens—birds, crocodiles, turtles, lizards, snakes or bats—must be presented to the Office of State Lands and Investments within 30 days of discovery for review by the Wyoming Geological Survey.

Carl was busy preparing a huge slab of rock, some three metres long, covered in a swarm of small fish fossils (Knightia). He had been working on it for weeks, between other jobs. He took me around his workshop, showing me many examples of his fine craft work, from tiny insects and large plants to many different kinds of fishes, including the rare examples that fetch high prices; fishes that have eaten other fishes, or two specimens juxtaposed in an unusual pattern. He then pulled out the remains of a small fossil bird.

'This is one I'll have to hand in to the authorities,' he told me. 'Bird fossils are very rare here.'

Another huge slab containing a perfect large palm frond and single small fish was his latest masterpiece, now almost finished. One small slip with the electric vibratool or drill, however, and the whole thing could be ruined. Unlike a master painter who can rework his brush strokes, or erase or cover up material to make the final image perfect, the fossil preparator has only one chance to extricate the perfect form of the fossil from the rock. Carl truly is a living master of his art. Every fossil prepared and sold by the Ulrichs is signed by Carl, his distinctive signature etched into the corner of each slab. The Ulrichs also issue a certificate of authentication with each piece. Many of the finest fish specimens are tastefully framed and sold as works ready to hang.

When I told Carl and Shirley I was a fish palaeontologist, they kindly offered to take me out to their quarry. One of their assistants took me in their four-wheel-drive, up a very steep slope to the top of a nearby white hill of flat, layered sediments, where the famous eighteen-inch layer was exposed. There, on a perfectly flat slab of shale, I could see the rippled layers of sediments in the shapes of little fishes. The fishes are detected by their outlines, before the slabs are quarried out and taken down to the lab for the delicate job of preparation. There are around a dozen or so quarries leased in the region immediately adjacent to Fossil Butte National Monument. Some of these quarries are on private land, others are on State land that is leased for the commercial mining of the fossil resources.

Rick Hebdon, who runs Warfield Fossils, allows visitors to come and dig up their own fossils on his private quarry for about US$35 a day. Hebdon believes that palaeontologists working in museums need to be able to raise money to buy fossils from the private sector. He has an extensive collection of fossil birds that once caught the eye of a palaeontologist from the Smithsonian Institute, but the museum wasn't able to raise the US$80 000 asking price for the specimens.

Although the fossil-quarrying industry in Wyoming seems well regulated, it hasn't always been this way, and collectors who poach fossils from government lands are still a major headache for law enforcers like Steve.

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