By Hannah Leggett, Seasonal Botany/Ecology Field Assistant

A crab spider lying in wait on a native yellow thistle. Photo: Hannah Leggett.

If you’ve spent some time around Nantucket’s marshes and harbors, you’ve probably found a spider crab or two, but did you know that crab spiders—yes, crab spiders—can also be found on Nantucket? Not to be confused with the similarly named crustacean, crab spiders are usually found on or near flowers, waiting for their next meal. This can include bees, butterflies, ants, and more—crab spiders aren’t picky! The “crab” in the common name for this family of over 2,000 spiders, the Thomisidae, refers to their sideways, “crab-like” gait and their large front legs that resemble pincers. Crab spiders use these powerful front legs to grab anything that lands nearby, holding whatever it is in place as they inject it with a potent venom, before digging in!

From reading this, you might’ve gathered that crab spiders don’t spin webs, unlike many of the spiders you’re probably familiar with. This is part of what makes crab spiders so cool! They rely on something else to lure their prey for them, camouflaging themselves to avoid detection by predators and prey alike. The spider above, for instance, has cleverly camouflaged itself to resemble part of a yellow thistle, a flower that bees love. Maybe it’ll catch one later…

Moving on though, some crab spiders can even change color over the course of a few days to match what they’re sitting on!

A White Banded Crab Spider feeding on a butterfly. Photo: Bonnie Ott, Maryland Biodiversity Project, 2012.

A great example of this is the White Banded Crab Spider (Misumenoides formosipes). Fun fact: female white banded crab spiders feed solely on insects, but the much smaller males supplement their diet with pollen and nectar (often from Queen Anne’s lace, Daucus carota) as they search for mates. This fact is exciting because Nantucket has a lot of Queen Anne’s lace, which blooms late July through August, so keep an eye out for white banded crab spiders on your next walk! This species of spider is widespread across North America and is found in most states, including Massachusetts, but I’m not sure if any have been documented on Nantucket yet. One was spotted on Tuckernuck in 2021, though. You can see it in the photo below eating a honeybee! I think we’ve got a good chance of finding the white banded Crab Spider here, given its wide range and since it has been observed on Tuckernuck.

White Banded Crab Spider on Goldenrod, Tuckernuck Island. Photo: Nick Dorian, iNaturalist, 2021.

Another Non-Web Spinner

Here are some bonus spiders for making it to the end! This is a mama wolf spider and her babies. We found her scuttling through the bearberry and goldenrod down at Head of the Plains. It was just around the time that school ends for the day, so we figured she was probably taking her kids home from school. Kidding about the last part! Spiders don’t go to school…that we know of anyway. Also, just to clarify, wolf spiders aren’t crab spiders. They belong to a different family of spiders known as the Lycosidae, a name that originates from the Greek word “lycos” or “wolf.” Much like crab spiders though, wolf spiders also hunt their prey instead of spinning webs. Fun fact:  since wolf spiders hunt at night, you can shine a light out in a field and see all their little eyes reflecting back at you from ground level.

Wolf Spider carrying young at Head of the Plains. Photo: Hannah Leggett.

Well, that’s all for spiders today! I hope folks can appreciate just how cool, cute, and yes, sometimes “creepy” these crawlies are.

Hannah with an armload of golden oyster mushrooms.

About the Blog Post Author:

Hannah is from Virginia, and just graduated from College of the Holy Cross in Worcester, Massachusetts in May 2023. She came to Nantucket excited to work here as a seasonal Botany Field Assistant because she has loved the Foundation’s work since she was a kid, exploring the island’s marshes, forests, and grasslands each summer. What Hannah likes best about plants is that you’re bound to find them wherever you go—they can be familiar or strange, and maybe even a snack! Basically, you’re never bored as a botanist! Hannah’s specific plant-related interests include foraging, herbal medicine, and sustainable agriculture. She hopes to run her own farm one day and also enjoys bee keeping, gardening, calisthenics… and spiders!