Santa Cruz Island
With an area of 96 square miles, Santa Cruz Island is the largest of the Northern Channel Islands and is also the largest island in the entire chain. It is situated 19 miles south of the Santa Barbara coastline. Anacapa Island, Santa Cruz’s closest island neighbor, is located 5 miles to the east.
Santa Cruz is the most diverse of the Channel Islands, in terms of its climate, geology, and topography. The maximum elevation on Santa Cruz (2470 feet) exceeds that of all of the other Channel Islands.
The flora of Santa Cruz Island includes about 490 native taxa and over 190 non-native taxa. The natural distribution of at least 45 of the island’s native taxa are restricted to two or more of the California Islands; eight plant taxa have been found only on Santa Cruz Island.
The eight plant taxa which have been found only on Santa Cruz Island are:
- Acmispon argophyllus var. niveus (Santa Cruz Island silver lotus)
- Arctostaphylos insularis (Santa Cruz Island manzanita)
- Arctostaphylos viridissima (white-haired manzanita)
- Dudleya nesiotica (Santa Cruz Island live-forever)
- Malacothamnus fasciculatus var. nesioticus (Santa Cruz Island bush-mallow)
- Mimulus brandegeei (Santa Cruz Island monkeyflower)
- Ribes thacherianum (Santa Cruz Island gooseberry)
- Thysanocarpus conchuliferus (Santa Cruz Island lacepod)
Common Names: Santa Cruz Island Fringepod, Santa Cruz Island Lacepod, Island Fringepod
Taxon Synonyms: Thysanocarpus laciniatus var. conchuliferus
Family: Brassicaceae (Mustard or Crucifer Family)
Presumed to be extinct:
The Santa Cruz Island monkeyflower (Mimulus brandegeei) is presumed to be extinct (it was last seen in 1932), although a close relative (Mimulus latifolius) still occurs on Guadalupe Island, off the coast of Baja California, Mexico.
At least one insular endemic is now found only on Santa Cruz Island, but had a wider range in the past:
- Berberis pinnata subsp. insularis (island barberry) was previously known from Santa Rosa Island (last seen there in 1930) and West Anacapa (last seen there in the 1980s). This taxon is now known only from a few small colonies on the west end of Santa Cruz Island.