Hudson meets three dogs when he travels to Provence.

Gaston is a Border Collie.
Border Collies are considered to be among the most intelligent and obedient of all breeds. They excel at herding because they can take direction by voice or whistle at long distances.

Philippe is a Lagotto Romagnolo.
They make good truffle hunters because they have a highly developed sense of smell, and they love to dig.

Sophie is a Standard Poodle.
This is a book that takes place in France, so of course there’s a French Poodle! Poodles were once bred as water retrievers. An unshown coat could weigh them down, so they were shorn to make them lighter and agile in the water, but with hair left to protect their joints from from cold. They even have webbed feet!