D N A E R RA RED ENDANGE
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an Nicolas fog lichen (Niebla ramosissima) is endemic to San Nicolas Island and is different f rom most ot her fog lichens because it grows on soil t hat is rich in t he mineral gypsum. The Garden’s Tucker Lichenologist, R ikke Reese Naesborg, has recently proposed t hat t his lichen be red-listed by t he International Union for Conser vation of Nat ure (IUCN) as ‘vulnerable’, one of t hree categories t hat indicates t hat t he species is t hreatened wit h global extinction. Invasive species and climate change, especially declining fog f requency, are potential t hreats to t he species.
Did you know? A lichen is not one organism. Each individual lichen is actually a little ecosystem. A lichen consists of one or more fungi in symbiosis with one or more green partners that can photosynthesize and therefore provide food for the fungus. Some people say that lichens are fungi that have learned agriculture!
Niebla ramosissima is asexual and spreads by fragmentation. Branches break off easily and scatter around the mother lichen. With a little luck, each branch will be covered with a thin layer of gypsum-rich soil that encourages stabilization and establishment of a new individual. Photo: Rikke Reese Naesborg
Although Niebla ramosissima sometimes covers large local areas, the only place in the world it grows is on San Nicolas Island, where it is threatened by several species of invasive iceplant (Mesembryathemum) that may eventually outcompete it. In this image, small iceplants can be seen as dark green subshrubs here and there between the fog lichens. Photo: Rikke Reese Naesborg W INT ER 2 0 2 0 Ironwood
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