We conducted ant surveys on Santa Cruz Island, the largest of the California Channel Islands, in 1975/6, 1984, 1993 and 1998. Our surveys yielded a combined total of 34 different ant species: Brachymyrmex cf. depilis, Camponotus anthrax, C. clarithorax, C. hyatti, C. semitestaceus, C. vicinus, C. sp. near vicinus, C. yogi, Cardiocondyla ectopia, Crematogaster californica, C. hespera, C. marioni, C. mormonum, Dorymyrmex bicolor, D. insanus (s.l.), Formica lasioides, F. moki, Hypoponera opacior, Leptothorax andrei, L.

Invasive species affect each of our lives, all regions of the U.S., and every nation in the world. Society pays a great price for invasive species - costs measured not just in dollars, but also in unemployment, damaged goods and equipment, power failures, food and water shortages, environmental degradation, increased rates and severity of natural disasters, disease epidemics, and even lost lives. Stimulated by the rapid global expansion of trade, transport, and travel, invasive species and their costs to society are increasing at an alarming rate.

Invading alien species in the United States cause major environmental damages and losses adding up to almost $120 billion per year. There are approximately 50,000 foreign species and the number is increasing. About 42% of the species on the Threatened or Endangered species lists are at risk primarily because of alien-invasive species.