Endangered and Threatened Wildlife and Plants; Proposed Rule for 16 Plant Taxa From the Northern Channel Islands, California

The U.S. Fish and Wildlife Service (Service) proposes endangered status pursuant to the Endangered Species Act of 1973, as amended (Act), for 16 plant taxa from the northern Channel Islands, California: Arabis hoffmannii (Hoffmann's rock-cress), Arctostaphylos confertiflora (Santa Rosa Island manzanita), Berberis pinnata ssp. insularis (island barberry), Castilleja mollis (soft-leaved paintbrush), Dudleya blochmaniae ssp. insularis (Santa Rosa Island dudleya), Dudleya sp. nov. ``East Point'' (munchkin dudleya), Dudleya nesiotica (Santa Cruz Island dudleya), Galium buxifolium (island bedstraw), Gilia tenuiflora ssp. hoffmannii (Hoffmann's slender-flowered gilia), Helianthemum greenei (island rush-rose), Heuchera maxima (island alumroot), Malacothamnus fasciculatus ssp. nesioticus (Santa Cruz Island bushmallow), Malacothrix indecora (Santa Cruz Island malacothrix), Malacothrix squalida (island malacothrix), Phacelia insularis ssp. insularis (island phacelia), and Thysanocarpus conchuliferus (Santa Cruz Island fringepod). The 16 plant taxa and their habitats have been variously affected or are currently threatened by one or more of the following: soil loss; habitat alteration by mammals alien to the Channel Islands (pigs, goats, sheep, donkeys, cattle, deer, elk, bison); direct predation by these same alien mammals; habitat alteration by native seabirds; habitat alteration due to vehicular traffic; overcollection for scientific or recreational purposes; competition with alien plant taxa; reduced genetic viability; depressed reproductive vigor; and the chance of stochastic extinction resulting from small numbers of individuals and populations.