Six-foot-eight and severely dyslexic, Brandon Vanderkool has always had an unusual perspective. He knows the mating calls of all the local owls, and can feel a flock of swans taking off before the sound reaches him. But he finds human feelings harder to read - especially lately.

His father has got him a job with the Border Patrol, a reluctant and miscellaneous outfit that polices the often invisible frontier between the United States and Canada. What used to be a sleepy hinterland of farms, with foreign neighbours saluting each other ironically over a shallow ditch, suddenly appears to have become the frontline of an escalating war on drugs and terror. As CCTV cameras sprout up all over the forest, previously law-abiding farmers find themselves increasingly tempted to turn a blind eye.

And Brandon, on his excursions to spot red-tailed hawks and solo tree swallows, seems to be accidentally stumbling upon every illegal immigrant and bud trafficker in the area. Closer to home, Brandon's father is dealing with d