Retrieve and Hunt are specialized sports for certain breeds of dog. Retrievers, Standard Poodles and Irish Water Spaniels can compete in retriever field trials. These same breeds plus the Barbet breed can also enter hunt and working certificate tests. Dogs are tested both on their ability to mark the location of downed birds and on their retrieving skills over land or in the water. At higher levels dogs are required to mark (watch the throw, sit and wait for the bird or bumper to land and then be released to fetch it) multiple birds and perform blind retrieves (the dog does not see the bird or bumper go down and the handler needs to direct the dog using whistles and hand casts). Most retriever breeds want to fetch so this sport encourages their natural instincts.