The world stayed right side up

Genelle Treaster

Photo by Larry Dalton

Lately we’ve all been hearing a lot about how “the world will never be the same.” Of course, the world has never been the same, or static, for more than an instant. Still, for many of us, the world has changed. It seems more frightening and more chaotic, and by reflex we wish for the impossible—that things would go back to the way they were.

It’s worth reminding ourselves, then, that there are pockets here and there where the world is much like it has been for hundreds, even thousands of years. The Cosumnes River Preserve in south Sacramento County is one of those places. The 40,000-acre wetlands habitat is one of a few last great chunks of natural habitat left in the Central Valley, home to dozens of threatened species, and one of the few remaining barriers to rampant suburban development.

The preserve is owned and operated by the Nature Conservancy (TNC) as well as a host of other government agencies, nonprofit organizations and individual farmers. We talked to Preserve staff member and wildlife lover Genelle Treaster about the life in the Cosumnes, one of California’s last wild rivers, the family life of cranes, and the peculiar eating habits of mountain lions.

The next few weeks are an ideal time to visit, as the preserve will be the home to millions of migratory birds from all over the Pacific flyway. Perhaps the most spectacular are the sandhill cranes, who stand over 4 feet tall, with wingspans that can reach 7 feet wide. Thousands of these cranes will fly from as far away as the Arctic Circle to make their winter homes here. The trails are open daily from sunrise to sunset. Call (916) 684-2816 or log on to

How does the Cosumnes differ from our other rivers, the Sacramento and American?

This is a wild river. That’s something that you don’t find anymore. It’s really the only place you can go to see what it looked like before we dammed everything. What it looked like before colonization.

Because it’s a wild river and it’s not dammed, it’s natural for it to be somewhat dry this time of year, and to flood in the winter. It used to be more wet than it is today. It used to be recharged by groundwater. But now the groundwater is overdrafted by development.

The Cosumnes is actually a pretty small river. That’s probably why it was spared. You know it’s not the mighty American or Sacramento rivers. There were proposals way back to dam it, but it turned out not to be financially feasible.

You know, I grew up in Sacramento, in College Greens along the American River, and spent tons of time at the river. But when I moved out here I couldn’t believe what a whole different managerie of wildlife there was here. I never really knew what a river was until I moved out here. Epecially when the floods happened. I mean this is what a river is, it’s not supposed to be the human carved finger of habitat like the American is. It is supposed to flood out over the plains. It’s supposed to have forests a mile thick.

What kind of critters live out here?

Certainly the Swainson’s hawk is an important one. He breeds here during the spring and summer, then goes to winter in Mexico. Sandhill cranes of course. We support something like 20 percent of the Central Valley population of these cranes. It’s critical habitat, meaning if they don’t have it their population will continue to decline. Cranes are completely site specific; an individual will land in the same field the next year. They are even known to land in parking lots after their habitat is destroyed by development.

They don’t reproduce until they’re 4 or 5, and they’re really family oriented. They mate for life, which I think is pretty sweet.

Cranes are also thought to be one of the oldest birds. Evolution-wise, some people think they are very close to the time of the dinosaurs.

Most people don’t know this but we are actually the staging area for the vast majority of migratory birds heading through the Central Valley. There are something like 10 to 14 million birds traveling the Pacific flyway.

Many of those stop and feed on their way through. Many more will spend the whole winter here. So we’re like a hotel and restaurant all in one for these birds. Soon there will be millions of birds. The ponds are brim to brim with birds, ducks and geese and cranes. It is amazing. It’s fabulous. I get kind of giddy during migration.


I do. I get giddy and I have a hard time staying in the office, because I get so excited to see the great push of birds coming through.

We have a lot of good mammals too. River otters, muskrats, badgers, which are of course a threatened species.

I heard there were mountain lions.

We always see mountain lions. They don’t breed in the Valley. There are no confirmed young anywhere around here. We think that they pass through. They use this corridor to get from mountain range to mountain range. This is the last area that they can get from the Coast Range to the Sierras unmolested. So we see them all the time.

We’ve had three reports this year, I’m sure there are many more coming through that people just don’t see. They’re very elusive, and don’t generally want anything to do with people.

Generally, but not always?

Well, we had one recently that was scary. Seven visitors in one day came and said they saw a mountain lion. Then someone said, “And he was following us.” So we actually had to close the trail.

He wanted to eat people?

He was hungry. And to a sick or an old mountain lion, people are actually pretty easy targets because we’re so slow. He was either really young and curious and hungry, or old and hungry or sick and hungry. But he was hungry, so we closed the trail. After about 10 days without seeing any tracks or scat we reopened, because he passed through. That was the first time we closed the trail for anything.