Banana Slugs: Secret of the Slime | Deep Look

Beneath the towering redwoods lives one of the most peculiar creatures in California: the banana slug. They're coated with a liquid crystal ooze that solves many problems slugs face in the forest -- and maybe some of our own.

Banana slugs are important members of the redwood forest community, even if they aren't the most exalted. They eat animal droppings, leaves and other detritus on the forest floor, and then generate waste that fertilizes new plants. Being slugs, they don't move very quickly, and without a shell, they need other protection to keep themselves from becoming food and then fertilizer. Their main defense: slime. Slime refers to mucus-the same stuff that coats your nose and lungs-found on the outside of an animal's body. Banana slug slime contains nasty chemicals that numb the tongue of any animal that attempts to nibble it, discouraging predators like raccoons, who have to go to the trouble of removing the slime if they want to eat the slug. But this is just one of many ways slugs depend on slime, and they use it for everything from locomotion to nutrition.

Read more in our article on KQED Science:

Funding for Deep Look is provided in part by PBS Digital Studios and the John S. and James L. Knight Foundation. Deep Look is a project of KQED Science, which is supported by HopeLab, The David B. Gold Foundation; S. D. Bechtel, Jr. Foundation; The Dirk and Charlene Kabcenell Foundation; The Vadasz Family Foundation; Smart Family Foundation and the members of KQED.
#deeplook

[epjones]

When I was a kid I used to get paid $0.25 per banana slug I removed from neighbor's garden to buy candy. Banana slug goo is tough to get off your hands and the candy always tasted funny.

[bigchunky]

"It's a liquid, it's a solid. It's a lolsquid"

[inquaanate]

So here's a thing, one time I was walking my dog and I came across a slug with loads of slime on it, I collected the slime (don't question this) and made a white ball maybe one or two cm across. If you pressed on the ball hard enough it would burst open and invert, I did this for several hours and it seemed to have a permanently renewable surface. Very interesting, should get some material scientists to test it some day.

[TheMoonMan.]

2:30 - so that's why we can't climb trees using our noses.

[bluefernlove]

I love slugs and snails. When I was a kid I used to think their trail of slime was fairy dust. I mean, have you seen that glittery iridescent path when the sun shines on it? 😍😍😍 it's fairy dust.

[brandonhall]

I really love the visuals and the sound design of this series. Great work!

[destinyashton]

i love the narrator's voice it's so calming and so fit for these kinds of videos

[HermeticAscetic]

"All inspired by the humble banana slug, our partner in slime." Hah! Awesome!

[edgarw]

gods whoever does the music for these videos, my hats off to you. it always invokes equal parts gross horror and sheer curiosity towards these creatures i can't get enough of deep look

[dickpee]

1:50
Liquid:my room

Solid:my friends room

[witherrose]

When I was a kid we had a lot of banana slugs around our house and I remember I took a bunch of slugs of various sizes and lined them up and called them a family. I still got the picture my mom took.

[vbgvbg]

Slugs and snails are adorable... Especially when eating.

[MUtley-rfvg]

I've acquired quite an affection for these guys having run across them several times here in the forests of the Puget Sound. They're large, bright, and totally out there. I love that you broke down the structure of their slime, its physical properties in relation to their means of locomotion, the slime's use as a signaling device and...food source? You made comparisons to slime in the human body, bio-mimicry in architecture and robotics, all in the span of 4 minutes! Whatever strange bent you're on, I wanna ride it.

[benb]

Way back I went to visit my Dad in California. Amongst the Redwoods I found a neat "Pet" in the form of a Bannana Slug.
Originally I caught a Red Racer snake but they talked me into letting it go.


But the slug was nice. Put him (Yes, I know now, Herma) in a large jar and he filled it halfway full, more slime than in his body. Hot and humid then so pulled out of the air... Crawled on sticks. Was about 6 inches long. Loved eating stuff I fed him, mostly fruit and greens.


Wanted to take him back to Montana... Dad insisted I had to let him out since winter would kill him or something...
Heh, good thing I did let him out, but insisted on going into the forest to let him go myself since Grandma kept looking at the garbage disposal when talking about how they'd release him into the wild. He was a lot bigger, close to 7 inches when I released him so I'm sure I fed him and treated him well, btw.

[_Obey_]

Please do more videos about slugs and snails! They are so fascinating and underrated! :D

[amytsab]

I'm going to UCSC and over there they have banana slugs and I'm excited to see them and the campus!

[xihearthesx]

I always get really excited when I see a new Deep Look video in my subscription box. Another great video! 

[virg_lemnade]

i live in Northern California so these videos are extra fascinating to me since that's where almost all of these were filmed!! haha

[MODGNAR]

The slime of these slugs is incredible, next time you visit California Redwoods I highly suggest finding one and playing with a bit of slime. The slime is like one of the longest lasting lubes ever. If you get it on your hands, you can run your hand under water for HOURS and it will still be slimy. Even soap doesn't help much.

Anyway this stuff is just fascinating.

[SunScourge]

I love your soundtrack. It's unique and fitting for every new episode! I always listen all the way to the end ^^