VALLEY CITY (AP) - It's not easy being a fish egg.

Predators and adverse water conditions kill many before they even hatch. In fact, only a small percentage of the fish eggs laid in a natural water environment actually live long enough to add to the fish population.

"Natural reproduction is kind of a hit or miss," said Ron Zitzow, manager of the Valley City National Fish Hatchery, located outside Valley City.

Often, bullheads, suckers or birds eat the eggs, said Ron Manson, biological science technician at the hatchery. Or silt from runoff covers the eggs, depriving them of oxygen. Changing water levels can leave some fish eggs high and dry.

That's where the National Fish Hatchery System comes in. Between 65 percent and 80 percent of the fish eggs incubated there hatch.

"You get a lot higher percentage of survival by doing it through the hatchery system," Mason said. "You don't have the predators, you don't have the silt."

The National Fish Hatchery System is made up of 70 fish hatcheries across the United States. In North Dakota, that includes the Valley City National Fish Hatchery and the Garrison Dam National Fish Hatchery near Riverdale. The hatcheries, operated by the federal Fish and Wildlife Service, have an obligation to restore native fish and mitigate the loss of habitat and recreational opportunities for fishermen, Zitzow said.

The Valley City National Fish Hatchery was established in 1938, to produce bass and bluegills. This year, the hatchery plans to stock more than 4 million fingerlings of yellow perch, northern pike, black crappies, bluegill and bass.

Locally, those fish will go into Jamestown Reservoir, Pipestem Reservoir, Lake Ashtabula and Devils Lake, Zitzow said. The hatchery also provides fish for other reservoirs and lakes across the state as well as some out-of-state locations, such as in Wyoming and Montana.

A new project for this year is raising lake sturgeon for the Red River or its tributaries, he said. The details of that project are being worked out.

"That's something that we're kind of excited about," he said.

The fish hatchery did raise pallid sturgeon in the late 1990s. The endangered species was stocked in the Missouri River.

The fish hatchery is just entering into its busy season for the spring, summer and fall, Zitzow said. It has rows and rows of glass hatching jars filled with the eggs of yellow perch and northern pike.

With the assistance of the Fish and Wildlife Service, northern pike eggs are collected lakeside from brood fish, he said. The eggs are fertilized, cleaned and brought back to the hatchery for incubation.

To gather yellow perch eggs, the brood stock is brought back to the hatchery and placed in tanks. Hatchery employees then harvest the perch eggs as they are laid in the tanks. All brood stock of all species are returned to their original environment once the fish eggs are collected, Zitzow said.

With yellow perch, once the fry, as the newly hatched tiny fish are called, begin hatching, they are put into fish ponds to mature. Northern pike are allowed to hatch in the hatching jars and then moved to holding tanks where they cling to burlap. Once they begin to swim, they are moved to a pond. Crappies and bluegills are captured and build nests in ponds at the hatchery.

"It's different with the different species," Zitzow said.

The Valley City hatchery has 13 ponds on site and another 20 ponds at the Baldhill sub unit. The ponds are all earthen and are filled with water from the Sheyenne River, Zitzow said. Once the fingerlings reach about 1 inch or 11/2 inches, the ponds are drained for harvest and the fingerlings are transported to area lakes and reservoirs.

Alfalfa pellets are added to the ponds, which creates the bacteria and algae that zooplankton feed on, he said. In turn, the fish feed on the zoo plankton.

The fish hatchery is open to the public, Zitzow said. More than 5,000 people stop at the visitor's center annually. The hatchery also offers hiking trails, picnicking, canoeing, camping. And there's a fishing pond for youth under 12, adults over 65 and anglers with disabilities.