If they had not worried about him during the day, they would be alarmed at night.
"There are some coyotes around the neighborhood," thought Jo.
He knew that a number of poultry-yards had suffered from coyotes.

Jo did not suppose that a coyote would usually attack a person.
Chickens, lambs, young pigs, were a coyote's prey, but in Jo's present situation he did not care to be visited by a coyote.
"I could throw clods at him," thought Jo.

"I hope that would scare him away." As the sun sank, Jo shouted repeatedly, till his breath was gone.

He hoped that some laborer might take his homeward way across the unfrequented hill.

But the prospect of such relief seemed very slight, so unused was this place to visitors.