A big ol hello from Elkhorn Slough located on Monterey Bay in Central California. FYI, a slough (pronounced sloo) is just another word for estuary–a place where freshwater meets the sea. I love this place cause it is always hopping with more than hundreds of different seabirds like white pelicans and black cormorants, cool fishes like leopard sharks, bat rays and midshipman and–what most people come here to see–loads of marine mammals! The waters are bubbling with California sea lions, harbor seals and more than 100 southern sea otters (Enhydra lutris). It’s pupping time right now so there are dozens of mommy otters with their little teddy bear like pups nestled up on their chests. Super cute!
Sea otters are big oceanic weasel relatives and they play a hugely important role here in the Slough. You may have already heard about how sea otters eat sea urchins and without otters, those urchins would multiply and devour the kelp forests of Monterey Bay and that would spell disaster for the hundreds and hundreds of critters that call kelp forests home.
What you might not know is how sea otters have helped bring Elkhorn Slough and its vital seagrass beds back to health too! You see before otters rebounded here, the slough was a gooey algal infested mess that suffocated the eelgrass beds. Too much fertilizer run-off from the agricultural fields has caused the algae to go wild. So what does that have to do with otters? I’m getting there!
Well you see, the otters in Elkhorn Slough eat crabs–lots of them—up to 400,000 crabs per year in an area the size of 7 football fields! The crabs meanwhile eat other animals like sea hares and isopods which both graze upon algae. So by chowing down on those crabs, otters inadvertently save the slugs and isopods, which can then graze the suffocating algae off the seagrass beds. Thriving seagrass beds filter the water of pollutants and make this whole habitat healthy.
What an amazing four-part chain reaction. It’s what we scientists call a “trophic cascade”. Just another reason to LOVE THOSE OTTERS!
If you want to learn more with Tierney, head to TIERNEY’S AQUARIUM located in CRYSTAL SANDS!