The first stone moved when Ysabet stepped over it.
She stopped so abruptly that Chaska walked into her pack.
“What?”
The stone unfolded a wing.
It was a bird, gray as wet mortar, with stiff narrow feathers that fit together like scales. Dust had coated its back. One foot caught beneath a thin fallen lath. When Ysabet lifted the wood, the swift rolled onto its side and tried to scramble away.
“Don’t chase it,” she said, mostly to herself.
Pip climbed from the basket. It was quicker now over level ground, though the small folded leg still dragged. The bird opened its beak. Pip stopped short and lowered its jaw until both creatures were nearly at the same height.
Behind the arch came another scraping sound.
Ashaun put down her pack. “More.”
The surviving span covered a dry shelf above the channel. When the bridge collapsed, a slab from the northern approach had fallen against its side, closing most of the gap between shelf and bank. The swifts could get in through narrow spaces between stones. Larger birds might have found a way out. The young beneath the shelf had none that opened onto a clear launch.
Chaska climbed the slope and looked down.
“Four. Maybe five. That one came up the crack.”
“The parents?”
“Above us.”
A gray bird swept past, so close Ysabet felt the wind against her cheek. It struck a high ledge, folded its wings, and became another piece of bridge.
The young swift on the ground fluttered forward. It struck the fallen slab and slid down, leaving dust in the seams of its feathers.
Ysabet took off her coat and laid it over a shallow hollow. Pip approached the bird, touching its own pouch with one fine foot. The swift pecked the foot.
Pip withdrew it immediately.
“A fair answer,” Chaska murmured.
They moved uphill to look for a way around the slab. Ashaun tested two stones, then called them back when a third shifted against the arch. The old bridge groaned from somewhere deeper inside. Ysabet could not see which parts supported which. Moving a block by guess might open a path or close all of them.
“We don’t pull anything out from under that,” Ashaun said.
Chaska crouched beside a narrow crack. “Could lay something over the rubble. A ramp.”
“With a clear top,” Ysabet said. “They need to spread their wings.”
The nearest landing stone was a little above her shoulder. Beneath it, broken rubble rose in loose tiers. Some pieces could be shifted without touching the arch if they worked from the outside inward.
Pip had begun already.
It dragged a palm-sized fragment toward the slab, put another beside it, and tested the pair with its forefeet. The young swift watched from the shallow hollow in Ysabet’s coat. It had stopped trying to flee the people, but its quick breathing remained visible beneath the scales.
Chaska brought the pole. “Here. We can brace the broad one with this while we work.”
Ashaun held the upper end against her stone forearm and leaned her weight into it. Chaska packed smaller pieces around the base. Ysabet moved the loose stones with her left hand, keeping Pip clear of the place where an edge might fall.
The creature clicked at her and dragged a stone back where she had taken it from.
“Not that one.”
It brought another. Then another.
At first Ysabet thought it was copying them. A line rose beside the ramp, straight and close-fitted. The fragments were chosen by size: broad at the bottom, small toward the top, with gaps offset so nothing could pass directly through.
Ashaun saw it too.
She stopped moving.
Pip set one last thin piece across a narrow opening. It tilted its head and inspected the work. The wall blocked the part of the ramp that would have let the birds spread their wings.
“Ysabet,” Ashaun said.
“I see.”
Pip went to the young swift in the coat. It put its jaw beneath the bird’s breast, very slowly. The swift flapped once, then settled against its warm folds.
The creature began pushing it toward the enclosed space behind the new wall.
Ysabet put down the stone she held.
“Wait.”
Pip’s feet stopped. The bird turned its head toward the parents calling above the arch.
Ysabet crouched beside the wall. The arrangement was familiar in a way that made her mouth go dry: a place protected from outside, a narrow route in, no broad way out. Pip pressed the small bird toward the gap with almost tender care.
Ashaun’s right hand hovered near her belt.
Ysabet reached for one of the stones at the wall’s end. Pip clicked sharply. She stopped with her hand beside it and let the creature see where she meant to move.
The young swift called again.
Above them, its parent answered from a ledge nobody had built.