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Invertebrates include insects, as well as anything other animal life that does not have a backbone. So things like cephalopods (octopus and squid) are invertebrates, as well as ladybugs, zooplankton, earthworms, clams and mussels, moths and butterflies, and a variety of critters we call benthic macroinvertebrates -- also known as stream bugs.

Stream Bugs and other Freshwater Invertebrates

The Puget Sound Stream Benthos website was developed by a group of agencies interested in monitoring the health of streams in the Pacific Northwest. The City of Seattle, King County, Pierce County, and Snohomish County worked collaboratively to create a database system that allows sharing of benthic macroinvertebrate data among many organizations and provides tools for calculating metrics and indices. The site is used to store and analyze data from ongoing macroinvertebrate sampling programs.

You can visit King County's Stream Bug Monitoring website to learn general information about benthic macroinvertebrates, why they are important in streams, how King County uses them as stream health indicators, and information on county streams that are being monitored. Next time you are walking near your neighborhood stream (after reading Your Guide to Visiting Watersheds), carefully pick up a rock. You might be surprised at what you find!

Freshwater Mussels are another invertebrate that may be found in our streams. Depending on the species, these animals often indicate good water quality. They are also a good reason to keep from walking in streams -- they often look like rocks and are easily squashed. And while their long-lived natural history is impressive (they can live to 100 years), that also means they don't produce many young. So they are unable to replenish their population if they are killed.

Marine Invertebrates

One of the most exciting and easiest ways to see a huge variety of invertebrate life in King County is to look in the marine environment! Our Marine Life photo site offers a glimpse into the variety of life found in the waters of Puget Sound. With multiple species of sea stars, crabs, clams, nudibranchs, octopus, squid, sea cucumbers, anemones, corals, and more, Puget Sound hosts a rich, beautiful, and dynamic biota.

Terrestrial Invertebrates

Pollinators are an incredibly important group of animals, but a group that people often do not consider. Some of our pollinators are vertebrates, like birds and bats. But there is a wide array of invertebrate pollinators -- like bees! Bees, wasps, butterflies, ants, flies, and moths play a critical role in the pollination of nearly all flowering plants -- including our food crops. Have you recently given up plastic grocery sacks for reusable ones? Well here is another step you can take in being a better earth steward by learning about pollinators and what you might do to help them. Curious what species of bee (or possibly wasp) you've found on your window sill? Here is a great pocket identification guide for western species (external PDF) from the Xerces society.

Every year as lake temperatures rise and the water becomes more inviting for swimming, people wonder about leeches. Some folks have water features in their yards, and after the family dogs tromps through the pond or fountain he comes back with leeches on his feet. Our leech website is intended to help answer questions about these little invertebrates.

Here in the northwest we don't have many poisonous animals. However, one spider that can cause problems if it bites is the hobo spider. Distinguishing which of the 800-900 spider species in Washington that you encounter is a hobo spider is the challenge. Maybe it's best to not get bitten by any spider. The author of this webpage finds that using a very large cup to capture spiders in the house and relocate them outside works nicely. For more information on the hobo spider, including its identification, we provide several good links on our hobo spider page.

So, did you notice that part about 800-900 species of spiders in Washington? Here is an older (1988) Annotated Checklist of the Spiders of Washington. It is presented with a lot of caveats about changes in the list since 1988, but it still provides a good idea of the amazing variety of these awesome animals.