Friday, 5/12 3:00pm 4:00pm (Pacific Time) 4:00pm 5:00pm (Mountain Time) 5:00pm 6:00pm (Central Time) 6:00pm 7:00pm (Eastern Time)

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1 Please join SCWW for our next Special Event: In Search of Banana Slugs Holding the title of second largest terrestrial slug in the world, California banana slugs (Ariolimax californicus) are brightly colored, banana yellow, and can grow up to ten inches long. Join us in search of this unusual creature in the redwood forests of California. Presented by Britt Bassoni, ESC Senior Resource Director of Santa Clara County Friday, 5/12 3:00pm 4:00pm (Pacific Time) 4:00pm 5:00pm (Mountain Time) 5:00pm 6:00pm (Central Time) 6:00pm 7:00pm (Eastern Time) To join by computer, click: To join by phone, call: (646) (US Toll Free) (888) (US Toll) Enter meeting ID: # After prompt, enter: # 1

2 SCWW Special Event: In Search Of... Banana Slugs! Presented by: Britt Bassoni 2

3 Banana Slugs are a type of mollusk - - invertebrate animals with a mantle, radula, and the structure of a nervous system - - from the word mollis, meaning soft. Other mollusk include octopus, squid, cuttlefish, and snails, as well as other slugs - - they are part of an incredibly diverse phylum. Snails and slugs are of one class of mollusks known as gastropods. 3

4 Banana slugs live in and on the floor of temperate coniferous rainforests and similar rainy-foggy-damp habitats within the long, narrow, mountainbacked Marine West Coast climate zone that stretches along the North Pacific Coast. 4

5 This habitat encompasses a huge area extending from the Salinas Valley of central California northward through coastal Oregon, Washington, British Columbia (west of the Cascades), and southeastern Alaska. Only in a few places does this range extend inland more than a couple of hundred miles. 5

6 Specifically, banana slugs are shell-less gastropod mollusks that belong to the genus Ariolomax. This genus includes three main species - - columbianus, dolichophallus, and californicus. There are also two known subspecies. The banana slugs which I search for are the Ariolomax californicus. 6

7 And, since banana slug searching discourages the keeping of secrets, here is a map of the search area and locations in which most of the following photos were taken. My favorite banana slug habitat is Butano State Park, just south of the town of Pescadero. 7

8 Banana slugs are stenotopic, meaning they can withstand only a limited range of variations in their environmental conditions. They need a mild climate, because severe cold will kill them; moisture, because severe desiccation will kill them; and, rotting plant and animal material must be plentiful, since this is what they eat. 8

9 If you really want to find banana slugs, it is best to search at night, since they are largely nocturnal. During the cooler and rainier winter months, you can also find them during the day. You can find them near creeks, in clumps of decaying leaves and other matter, and in and around old stumps and root tangles. 9

10 And, if you happen to spot a banana slug, there will be little doubt you ve found one, because nothing else looks quite like one! They can grow six to ten inches in length, are bright yellow, or yellow with back spots, and have two distinct sets of tentacles - - the lower and smaller set for feeling and smelling, and the larger and upper set for seeing. 10

11 A couple of other distinct features include the slug s radula - - a tongue-like organ covered with a countless number of small teeth, and located in the mouth between the bottom set of tentacles; and the slug s trademark mucus coating, or slime - - used to prevent dehydration, to aid in movement, and to discourage predators. 11

12 In addition to these uses, the slime also protects the animal s soft body from sharp rocks and twigs, as well as containing pheromones that help the slug to attract a mate. Mating is made easier by the fact that banana slugs are hermaphrodites - - each having both male and female reproductive organs. 12

13 During an elaborate courtship dance two or more slugs will circle each other, nipping and bumping one another with their tails. As the slugs dance they eventually intertwine and become excited, taking turns transferring sperm from one to the other. An impregnated slug will eventually lay between 3 and 50 eggs in a sheltered spot. 13

14 The baby banana slugs hatch within a month or two, and usually are fully mature a few months later. Initially they are paler than their parents, but quickly gain their yellow coloring through eating the same decaying materials as their parents. They are usually indistinguishable in color by the end of the first year. 14

15 To conclude..... Banana slugs are amazing creatures. They are an essential part of an incredibly diverse ecosystem, and they help to maintain the health of the forests in which they live, as well as help to support other insects, animals, and birds through their activities, and as a food source. 15

16 And.... they are true cultural icons.... Praised in song, referenced in movies, honored at festivals, and the subject of caricature, lore, legend, laughs, and even.... yes.... even love! 16

17 Finally.... remember that the best way to find banana slugs is to do as they do, and don t be afraid to get down in the dirt! The world is EVEN BIGGER from down here! 17