Hello and thank you for contacting Ask An Expert.
Coincidentally enough I live in Anvil Park and I am leaning towards the resident Groundhogs that live all over our area. Given the cracks in the deck I'm thinking that there may have been insects living in the wood - Groundhogs do eat insects and may have been after something living in the wood. Another reason could be related to the Groundhogs alternate name - Woodchuck! Woodchucks are in the squirrel family and also must gnaw constantly to keep their incisor teeth from growing. Like squirrels, woodchucks will gnaw randomly on decks, siding, and outdoor furniture. My neighbor had similar damage a few years ago but once she replaced the affected boards the Groundhog didn't return. The best thing to do would be to contact a qualified wildlife control company. They will be able to give you a specific plan to deal with the offensive rodent.
You will receive a brief survey to let us know how we are doing and what we can do to improve our service. Please take a moment to fill it out!!