Searching for Slugs in the Santa Cruz Mountains

You haven’t fully experienced Santa Cruz County until you’ve hiked through a redwood forest still dripping from a hard rain. The canyons are filled with the sound of rushing water. Wrens flit between the lichen-draped brush of the understory, and the silvery warble of a Swainson’s thrush filters down from the latticework of branches spiraling hundreds of feet above your head. As a hiker, however, the most fascinating part of a rain-soaked coastal redwood forest is right beneath your feet. When the ground is well saturated, you don’t have to look hard to spot Santa Cruz’s favorite slimy gastropod, the banana slug. In fact, after a particularly hard rain, you may have to watch your step.

During dry spells, banana slugs hunker down and go into their version of hibernation. This is why your best bet for seeing one is to get out into the forest while the ground’s still wet and there’s a winter chill in the air. Of course, most people don’t consider winter the best time for hiking, but with quieter trails, a rainbow of lichen and mushrooms, and roaring waterfalls that reduce to a trickle in summer, banana slugs are only one reason to venture outdoors in the “off-season.” Another bonus to exploring right after (or during) the rain—you just might share the trail with the California newt as well.

Where to Find Banana Slugs in Santa Cruz County

When choosing your hike, look for parks that are dominated by redwoods and have ample water—both things easy to find in Santa Cruz County which is partly why the slugs love it here. We also have a temperate climate with mild winters and summers that cater well to the slug’s sensitivity to extreme temperatures.

Before venturing out on the trails, however, it’s important to check the State Park’s website for trail closures, especially in winter and early spring when storms can cause erosion, downed trees, and tricky creek crossings. For year-round, easy slug spotting adventures, Henry Cowell State Park offers kid-friendly hikes and wheelchair accessible jaunts beneath the redwoods. Nestled in the heart of Aptos, Nisene Marks State Park has winding trails that border a redwood creek canyon and miles of dog-friendly trails. Last but not least, Rancho Del Oso State Park, at the mouth of Waddell Creek, is a scenic drive up Highway 1 and also a great place to see both slugs and newts.

Surprising Slug Facts

While simply observing a banana slug in its natural habitat is a thrill, its strange biology, not to mention famous cultural ties, add a new level of appreciation to your slimy discovery. After all, we’re talking about the second largest slug in the world, stretching to a shocking 10 inches in length. (That’s the size of a cucumber or a women’s size 10 shoe!) Besides their incredible size, there are countless weird, fascinating facts about the banana slug that will leave you itching to get on the forest trails and scan the redwood duff for these giant slime rappelling, tongue numbing, hermaphroditic mollusks.  

Slime is Their Secret Superpower

A banana slug’s slime is no ordinary mucus. Somewhere between a liquid and a solid, it’s both an adhesive and a lubricant. Its stickiness allows banana slugs to ooze up tree trunks and rappel down from high branches on a rope of their own mucus. Its slipperiness keeps the slug from shriveling up like a raisin when the sun comes out and allows it to easily slide over the rough redwood duff, twigs, and sharp rocks on the forest floor. Pheromones found in their shimmery slime trails also help them to find other slug mates. As hermaphrodites, however, slugs don’t technically need a mate to reproduce, but most of them still choose to procreate the old-fashioned way.

Most famously, banana slug slime contains an anesthetic that instantly numbs the tongue of hungry would-be predators and adventurous hikers. A word of caution to those with ‘kiss a banana slug’ on their bucket list. Even though it’s rumored to bring good fortune, even a small peck can transfer harmful bacteria to the slug’s organs. (Plus, it tastes horrible.) Their skin is extremely porous and readily absorbs any nutrients or chemicals it comes into contact with, including those found on your lips and skin. So, take all the banana slug selfies you want, but keep it clean and keep your hands to yourself.

They Age Like a Banana

The iconic banana slug that adorns UCSC schwag and dominates Instagram is a bright yellow that stands out amongst the deep browns and greens of their shady forest habitat. That Sammy-the-slug yellow, however, is only one stage in the terrestrial mollusk’s 7-year life cycle. Younger slugs may be bright and showy, but with age, the slug slowly fades to brown. What they eat, their health, and light exposure can also affect their color, resulting in a range of hues from green, black, and white to spotted.

They Beat the Sea Lion as UCSC’s Official Mascot

UCSC has always been known for its cultivation of individuality and for fostering a community of free thinkers who openly challenge the status quo. It’s only natural that their mascot would also push the envelope and stand out from the pack. The banana slug was chosen as the school’s unofficial mascot from its early beginnings, but in 1980 the chancellor hoped to make the switch to the more powerful and intimidating sea lion. The students rebelled, continuing to cheer for the slugs even after the chancellor painted the sea lion on the basketball court floor. In 1986 the mascot went up for a vote and the banana slug won by a landslide.

Since then, Sammy the Slug has been voted one of the weirdest, best, and worst team mascots in college sports. He also made a cameo appearance in the cult classic Pulp Fiction when John Travolta sported the ‘OG’ UCSC banana slugs t-shirt. Pick up your own at the Bay Tree Bookstore on campus or downtown at Bookshop Santa Cruz.

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