Ground beetles stalk the refuge forest floor in search of prey/Photo Courtesy of Dr. Madeline Kalbach

Invertebrates are animals without backbones. From the forest floor to the bottom of Willapa Bay, you'll find invertebrates nearly everywhere at Willapa National Wildlife Refuge.

  • Clams & Oysters

    Littleneck clams are abundant in the gravelly areas of Willapa Bay/USDA Photo Ken Hammond

    The clean, shallow waters of Willapa Bay teem with oysters and clams. These filter feeders have two hard shells held tightly closed with a hinge and several stong mussels to protect their soft bodies from predators.

    Find out more about clams...

    Discover more about Willapa's oysters...

  • Crustaceans

    Dungeness crab thrive in Willapa Bay/USFWS Photo

    These crusty critters have an extra think hard outer shell, ofetn with pieces fused together to pritect it's soft interior. Crustaceans include crabs, shrimp, barnacles and even pillbugs.

    Discover some of Willapa's crustaceans...

  • Freshwater Mussels

    Western pearlshell mussels live in refuge streams/USFWS Photo

    Did you know there are mussels living in refuge streams? They may look dull and sedintary, but this animal has a unique life.

    Uncover the secrets of the freshwater mussels...

  • Insects

    Dragonflies are a common summer sight near refuge wetlands/Photo Courtesy of Dr. Madeline Kalbach

    Insects are the largest and most diverse group of arthropods (animals with hard outer shells and jointed legs) and include flies, beetles, butterflies, bees and more.

    Learn more about refuge insects...

  • Slugs & Snails

    The bananna slug can look like a rooten bananna with its yellow skin and black spots/Photo Courtesy of Rollin Bannow

    Soft bodied animals, related to clams and mussels, slugs and snails thrive in the moist vegetation and soils at the refuge.

  • Spiders

    Orb weaving spiders build a new web each day and sometimes "recycle" the silk by eating it/Photo Courtesy of Rollin Bannow

    Spiders differ from insects in that they have eight legs and only two main body sections. All spiders have silk glands, but not all of them build webs. There are three main families of spiders found in the refuge: orb weavers, jumping spiders and crab spiders. They are all predators and serve an important function in the web of life.