White Faced Ibis Make a Comeback

If you are up towards Knights Landing lately, or crossing over the Yolo Causeway on Highway 5 or Highway 80, you may have noticed black birds with long, curved beaks: white-faced ibis. Until about three years ago, I never noticed them around Knights Landing. This year they are very abundant, which piqued my curiosity about these birds.

Evidently, the white-faced ibis are making a comeback. Their populations were decimated in the 1960’s and 1970’s by both wetlands destruction and by chemical pesticides. You see, these guys are opportunistic feeders. They like the ground covered with water, and like our ducks do at home, they like to poke around in the water for earthworms, snails, insects, newts, leeches, and crayfish. They will also eat frogs and fish. And I suppose like the egrets that also hang out in the alfalfa fields near Knights Landing, they eat small rodents that run for their lives when the fields are flooded.

They also really like emergent vegetation—which is just a fancy science speak for short, newly grown plants. This makes sense, given that what they eat isn’t easy to find if the vegetation gets large. So again, the alfalfa fields, which are regularly cut and flooded are the perfect feeding places for white-faced ibis.

These ibis are also like the social networkers of the egret family. They love hanging out in large groups and are very social. They are pretty flighty and shy. Unlike the egrets we have around here, who will stand stock still sometimes if you approach them, the ibis are a little jittery. More often than not, they will take off as soon as you stop for a photo.

And I would love to get a good photo of them. They are vaguely exotic looking – with their beautiful curved bill and glossy black feathers. When they fly in large groups, they form irregular “V” shapes, but more often I see them in smaller groups, flying in a single line.

Personally, I think that a lot of the white faced ibis’s comeback in Yolo County is due to the Yolo Basin wetlands near Davis. The wetlands are relatively new to Yolo County and since it has been set aside, I have noticed much more diversity in our wetland birds. The wetlands give the Ibis a safe place to roost for the evening, and also provide nesting sites for the ibis. Since ibis will abandon their nests if disturbed and in some studies only successfully raised one young per pair per year, undisturbed nesting sites are crucial in the survival of this beautiful bird.