By Emily Grason

Within the discipline of marine biology, those who study rocky and cobble shores get the glamorous work. In the Pacific Northwest, I bet the places that most of us imagine marine biologists working are the dramatic sea stacks of the outer coast (rocky), or amidst the mind-blowing diversity of sea beasties uncovered at Alki Beach (cobble) on good low tides.

But what of the lowly mudflats? I am a marine biologist. I study mudflats because they harbor more invasive species than other intertidal environments. But what does it mean to study mudflats? If no particular images pop into your head, allow me to help.

Mudflats are muddy, and expansive, and flat. They are muddy and expansive because they are flat. They are flat, because they are calm. Just like a raging river is brown with dirt dredged up from the bottom, big waves scour seashores of sand and other small sediments. Only big heavy stuff remains, cobble and bedrock. On the other end of the spectrum, sediment settles out of the very calm waters of estuaries, even tiny mud particles, much like how Metamucil accumulates at the bottom of your glass if you stop stirring.

So, start by imagining me out there, way out there, even farther out there than you are already imagining me, in the middle of this huge, flat, muddy … flat.

The author in her natural environment. Mudflats at Scandia, Liberty Bay, WA were the site of a study on the effects of invasive predatory snails on native oysters during the summer of 2011, in partnership with the Puget Sound Restoration Fund. Photo Credit: Nima Yazdani

And there is an amazing, bubbling, sizzling sound coming from every direction, as the water slowly drains off the flat with the ebbing tide, trickling into rivulets, through the eelgrass meadows and oyster hummocks. It’s a sound you can feel in your skin, like the noise bath bubbles make when you’re submerged up to your neck in the tub. My plunging, lurching traverse of this mudflat is echoed in the arrhythmic “thwock, thwock” of my boots, as they break the vacuum of mud suction with each step.

Olfactorily, mudflats have a bouquet that some consider “bad” or “heinously offensive”. Because there are no waves to replenish the water in the mud, the worms and such that live in the sediment rapidly deplete the oxygen. But, far from being devoid of life, this mud harbors rich communities of bacteria that don’t require oxygen to breathe. The unfortunate downside of doing business as an anaerobic bacterium is that you release hydrogen sulfide – you smell like rotten eggs. Unfortunate, of course, only by human standards. The bacteria don’t particularly mind, I imagine. I even like the smell a little bit, because it’s a visceral reminder of highly productive ecosystems.

And the mud. There is no version of mudflat fieldwork that is clean, even relatively. Mud becomes a part of my wardrobe, my car, my diet, and every interaction in my life throughout the field season.

The author finds a worm in the Willapa Bay mud in 2009.

So, this is mudflat ecology. I come home from the field, smelling like brimstone, looking like the child of Swamp Thing, and tracking God-knows-what  through the building. But, maybe I underestimate the glamor involved. We do have our own soundtrack, signature fragrance, and fashion line (hip waders = ecology GoGo boots!). It’s not ecological limos and red carpets (imagine the footprints!), but research on the mud is every bit as engaging as research on the rocks – if you’re not afraid to get your boots a bit dirty.

Emily wanders the mudflats of Washington’s estuaries, seeking an understanding of how invasive species impact our coastlines, and stable footing in the mud.  You can learn more about her love of gastropods at Rah Rah Radula.