A pint-size gray fluff ball peeps its head out of its twig nest, only to see its own tiny reflection in a mirror.

A pint-size gray fluff ball peeps its head out of its twig nest, only to see its own tiny reflection in a mirror.

Just underneath, Hannah Holden - armed with her 6-foot ladder and a 15-foot mirror on a pole - scribbles her daily observations on a 5-by-7-inch note card.

After she finishes with this nest, there will be plenty more for her to examine.

Every year, approximately 4,000 migratory birds take up temporary residence in a tree line on North Doris, near 13th Street and I-235 in west Wichita, and this year it's Holden's job to track 30 of their nests, The Wichita Eagle (http://is.gd/5l2l5t) reports.

Holden, 24, a student at Wichita State University, is writing her master's thesis on the population dynamics of Wichita's snowy egrets - what the colony's rate of growth is. This is a two-year project for her.

Every day, she takes her ladder and mirror and monitors how many chicks and eggs are in each of the 30 nests she observes. If one out of four eggs in a nest hatches and survives, she considers it a successful nest, she said.

The birds have been nesting here for more than 25 years, she said. It is not uncommon for birders from different states to come see these birds, while some Wichitans don't even know they exist, she said.

"I think they're actually doing pretty well here in the colony," Holden said. "I think their numbers have increased over the years."

The spot just south of the Sedgwick County Zoo is not the first place they have nested in town, said Bob Gress, former director of the Great Plains Nature Center. In the early 1980s they nested in the Haysville area. Then they moved to the Chisholm Creek Park area, while some started a colony on the island by the Twin Lakes shopping center.

The birds then moved to their current nesting spot, though Gress said it is possible they are nesting in other areas in town.

Construction on a bridge over I-235 is currently under way less than a block away from the trees, but Holden said that has had minimal effect on the birds.

"It's so important to conserve this colony," Holden said. "I hope people realize it's a blessing we have these birds here."

Not all of the neighbors think the same way.

Traci Terrill, 38, gives Holden access to the trees in her yard, though now more than half of them have been chopped down. She said she did it to prevent the birds from taking over her backyard.

"You can't beat them so you have to learn to live with them," Terrill said. "It was the intent that they would go away, but they haven't."

Terrill says she occasionally finds crawdads and once found a live minnow flopping around in her yard, brought in by the birds. She said she recently received a violation from the city for having an overgrown yard, which she said she can't mow due to the birds.

"I can't mow it because the birds are there, and I can't cut down the trees either," she said.

She said she sleeps with her window closed every night to protect not only against the birds getting in, but against the accompanying smell. Living with these inconveniences is worth it to live with these birds, which are "really awesome to look at," she said.

"The only downfall is that all of our lawn furniture, our cars, everything gets covered in bird (poop)," Terrill said.

Migrating egrets are protected by federal law, under the Migratory Bird Treaty Act of 1918. They typically start arriving from the south Texas area around late March and early April, Gress said. Wichita's little blue herons have the farthest journey, he said, coming from South America, as far as Chile. After their chicks have fledged, most leave town by mid-September and October, he said.

The colony is home to five species of egret - snowy, cattle, little blue herons, great egrets and night herons. In addition, three other heron species nest in Wichita every year, though they are rarer and do not typically nest in the colony, Gress said. They are the great blue heron, the yellow-crowned night-heron and the green heron.

Snowy egrets, which Holden is studying, have black legs with yellow "slippers," she said.

Cattle egrets, named for their tendency to hang around cows in fields, are characterized by slightly orange feathers on the crown of their heads, and on their chests and backs. In recent years,Wichita's population of cattle egrets has grown, Holden said, so much so that they make up approximately 80 percent of the egret population.

Most of the birds can be seen while staying on public property.

Holden said there is a lesson to be learned from the birds.

"Our five species out here nest within a few feet of each other, but they all get along," Holden said. "It's a good life lesson for me."