What happens when plants and animals find themselves a long way from home? Find out what happened when the hedgehog, the cane toad and the Chinese mitten crab came to stay. Pests on the Loose! is at Oxford Reading Level 13. It is for readers aged 11 to 13 years old who are working below expected standard in their reading. The Readerful Rise series ensures that older struggling readers have books with age-appropriate content and topics, that looks like the books their peers are enjoying, but are a written at a level they can read successfully.