MOAB — Not much bigger than a thumbnail, these razorback larvae must be a curious thing to behold as they wiggle, squiggle and earnestly make a treacherous journey to a safer place where they can grow, increasing their chances to survive another day.

Katie Creighton, the native aquatics project leader with the Utah Division of Wildlife Resources, is enthralled with this fish, which lives only in the upper Colorado River basin and is on the federal government's endangered species list.

"They're like a rice noodle with two eyeballs at that stage," she said. "I think they're sexy."

The Utah wildlife agency and the Nature Conservancy are partners in a joint effort to construct the first-ever fish nursery on the expanse on the 1,450-mile Colorado River.

The $1 million project is entering phase two of construction in the midst of the only significant wetlands along the Colorado River in Utah at the conservancy's Scott M. Matheson Wetlands Preserve.

Linda Whitham, the conservancy's central canyonlands program manager, said the project is a long time in the making, dependent on grant money, donations and supporters. How soon it will be finished — with its safe haven pond and structural gates to keep away predators — depends on availability of money.

"We've been hoping to get to this point for four years now."

The project is using a natural channel from the Colorado River that historically flooded the wetlands every other year, creating natural eddies for the larvae to escape from predators.

The last time there was in flooding in this area, however, was in 2011 in the aftermath of an exceptional year for snowpack. Excavating and dredging the channel will allow the tiny larvae passage to safety in years absent a flood but where flows are high enough.

Whitham said the lack of those hiding places drastically affects the species' ability to survive to the juvenile stage.

"There are too many nonnative fish grabbing them up like finger food."

Saving the razorback sucker and three other endangered species of fish endemic to the Colorado River system is a decades old, expensive effort.

The razorback sucker, which can live as long as 40 years, reaches 3 feet in length and dates back millions of years.

Interference of its habitat over the years led to the species' decline and a federal recovery program involving the U.S. Bureau of Reclamation and the U.S. Fish and Wildlife Service.

Successful efforts on tributaries like the Green River and San Juan River helped propel the U.S. Fish and Wildlife Service to announce that a downlisting of the fish is under consideration.

This nursery will assist in the elaborate conservation effort.

A gate at the channel at this preserve will allow the small larvae to make it to the pond and keep the predator fish at bay.

From there, they transform into juvenile fish and reach the stage where they are able survive outside the protection of the nursery.

The razorback sucker, Creighton explained, is sort of an unofficial indicator species that illustrates the health of a river ecosystem.

If they are failing, then something in the Colorado River — deemed the hardest working river in the West — is also failing.

Being involved in an effort to save an aquatic species that has been part of that system for 3 million years will be a generational tale lasting for years among these folks.

"Taking care of these natural resources, this is what you are in it for," said Nicole Nielson, a restoration biologist for the state, a smile spreading across her face.