"I would do research on the falcon's natural predator, the Great Horned Owl. Has there been an increase in the local owl population?"

"You might also look into humans! Some farmers shoot raptors because they think the birds are eating their chickens."

"Another possibility is that interference in the falcons' nests could cause the birds to abandon their eggs. Climbers who scale the cliffs where the birds nest could play a role."

"Those are my first thoughts, but they're just guesses. You might want to get someone else's opinion."