The Galapagos Islands vary from tiny rocks barely above the waves to enormous volcanic peaks rising from the
ocean to over 5,000 feet high. With the increase in elevation, average temperatures are cooler and rain falls
more often. The change in climate favors different vegetation from that at lower elevations. This leads to a
distinct zonation of plant life, with as many as seven recognized zones on larger islands. Smaller islands with
lower elevations may only have one or two zones. The zones are:
• Coastal zone: 0 to 100 feet — shore plants, succulents, salt bush, mangroves
• Arid zone: 100 to 1000 feet — succulents, cacti, some flowering plants, trees, shrubs, lichens
• Transition zone: 300 to 1500 feet — trees, shrubs, herbaceous plants, epiphytes
• Scalesia zone: 800 to 2100 feet — daisy trees (Scalesia spp.), shrubs, herbaceous plants, epiphytes
• Brown zone: 1500 to 1800 feet — cat's claw, mixture of scalesia and miconia zone vegetation
• Miconia zone: 1800 to 2000 feet — miconia (Santa Cruz and San Cristóbal islands only)
• Pampa zone: over 2000 feet — ferns, tree fern, mosses, sedges
As you can see from the picture, the zones may overlap, depending on the direction of the prevailing wind since
areas on the windward side receive more rainfall than those on the lee side.
(Image adapted from figure provided with permission courtesy of Michael H. Jackson, from Galapagos: A Natural History, University
of Calgary Press, 1993)
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