After Years of Severe Drought, White-Faced Ibis Colony Returns to Nest at Sacramento Refuge

White-faced ibis.

The white-faced ibis typically spend their summers breeding in western states, but about 25 years ago, they began showing up on Sacramento and Colusa National Wildlife Refuges. For the first time in recent years, refuge managers observed ibis breeding on the complex’s wetlands. Credit: Alan Schmierer/Flickr Creative Commons

By Byrhonda Lyons
September 27, 2016

It was a sunny, 90 degree day in early August as Craig Isola drove across the Sacramento National Wildlife Refuge near Willows, Calif.

“Last year at this time, there was no water in this wetland,” he said, pointing towards the passenger side window, describing how things used to be on the refuge.

As he led the tour group through an area that is normally closed to the public, his finger directed everyone’s eyes to the right. The area was nothing like he had described. Instead of spotting a dry field or decomposing plant residue, there was a wetland filled with water, lush vegetation and thousands of white-faced ibis.

Three white-faced ibis fly in the distance while hundreds of others gather in the wetlands on the Sacramento National Wildlife Refuge in Willows, Calif. Credit: Byrhonda Lyons/USFWS

Isola has worked at the refuge for more than 18 years and is currently the deputy project leader for the refuge complex, a collection of five National Wildlife Refuges and three Wildlife Management Areas in the upper Sacramento Valley.  He has observed the drought first hand.

Historically, white-faced ibis were regulars in California. However, “in the 1980s, there were almost no ibis in the Central Valley,” Isola said. “The majority of them were nesting in the Klamath Basin and the marshes surrounding the Great Salt Lake.”

White-faced ibis on Sacramento NWR.

This small group of white-faced ibis were captured
by local wildlife photographer Hazel Holby out on
the Sacramento National Wildlife Refuge in August.
Credit: Hazel Holby/USFWS

White-faced ibis are dark wading birds with downward curving bills. They typically spend their summers breeding in western states, and about 25 years ago, they began showing up on Sacramento and Colusa National Wildlife Refuges.

At the time, they were a rare sighting, he said.

The birds prefer wading and foraging in shallowly flooded water.

When the Great Salt Lake marshes flooded in the early and mid-1980s, historic breeding and foraging areas were too deep for the ibis. They had to find other suitable wetlands.

According to Isola, wetland restoration and enhancement was happening in the Central Valley during this time. The conditions were perfect for the birds to make their way back to the Valley.

The birds are now year-round residents of the Sacramento Valley, breeding in permanent and semi-permanent wetlands during the summer, and foraging in seasonal wetlands and flooded rice fields throughout the fall and winter.

While it’s normal today to see white-faced ibis on the refuge, scoping out nesting ibis is pretty rare.

For the first time in recent years, refuge managers observed ibis breeding on the complex’s wetlands. Years ago, a small nesting colony of 125 white-faced ibis showed up on the refuge.

In 2016, more than 5,000 ibis were nesting on the refuge’s semi-permanent wetland. Wetland units in “Tract 2” are home for the ibis colony. Last summer, this same tract was dry.

“The last two years, our water was cut to 75 percent (of normal),” said Steve Emmons, refuge manager.

With less water, refuge managers had to decide which wetlands to flood and which ones to leave dry. It was a tough decision.

“We used data from our wildlife surveys to determine which units would be best to flood,” Emmons said.

But that was in 2015. This summer, the refuge has normal water supplies.

Wetlands on Sacramento NWR.

Thousand of white-faced ibis in this colony nest on a wetland on the Sacramento National Wildlife Refuge near Willows, Calif. White-faced ibis will typically lay 3 to 4 eggs each season and both parents will care for the young. Credit: Hazel Holby/USFWS

Refuge managers are able to flood all of their permanent and semi-permanent wetlands, substantially increasing the wetland acreage on the refuge.

“Providing summer water for permanent and semi-permanent wetlands is important for white-faced ibis," Isola said. "However, these wetlands also provide habitat for a number of other sensitive species as well—such as giant garter snakes, tri-colored blackbirds and western pond turtles.”

While having the water resources to flood more wetlands is critical to providing habitat for ibis, Isola did not stop there. He added that years of investment in establishing and managing wetlands in the Central Valley is another reason ibis are nesting on the refuge.

“A lot of wetland restoration, enhancement and increased management of summer water brought these birds back,” he said. “And we’re looking forward to seeing more in the future.”


Byrhonda Lyons is a public affairs and social media specialist for the Pacific Southwest Region's office of external affairs, located in Sacramento.