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42 ploy, Sh WLAO, a breed. For that reason conservation must be accomplished with "purebred" breeding animals. Types of breeds Four breed types are found in North Amer- ica: industrial stocks, standardized breeds, landraces, and feral populations stocks. Each of these types differs according to its development, its selection history, the level of uniformity and the role of human breed- ers. Industrial stocks originated from either a portion of a standardized breed or a cross between two or more standardized breeds, with further selection for maximum per- formance in a closely controlled environ- ment. Examples are Holstein dairy cattle and Cornish Rock broilers. A standardized breed is a product of close human selection for specific production characteristics and phenotypic uniformity. Standardized breeds usually develop within a structure that may include herd books, in- dividual pedigrees, breeders association. Most breeds in the US are of the standard- ized type and of British, European or more recent American origin. Examples are Cleveland Bay horses, Brown Swiss cattle and Katandin Hair sheep. A landrace breed is a product of strong natural selection with minimal human selec- tion. They are well adapted to specific envi- ronments and have excellent reproductive and survival characteristics, rather than ag- ricultural production characteristics. Land - race individuals are often variable in appear- ance but exhibit a genotypic uniformity. Page 9 These breeds have survived where range laws persisted longest, in the South and West of the US. Since these areas were un- der strong Spanish influence, many of our landrace breeds are criollo breeds. Exam- ples are Texas Longhorn, Florida Cracker, Pinewoods cattle; Navajo - Churro and Gulf Coast Native sheep; Spanish goats; Spanish Mustang horses. Feral populations result when animals es- cape or are released from human manage- ment and once again live under natural se- lection. A few feral populations in North America have been isolated for a long time and have come to fit the genetic definition of a breed. Some of these feral breeds are being conserved in their natural habitat (in situ) while others are being conserved (ex situ) by re- domestication in the hands of breeders. Two examples of Spanish founda- tion feral breeds are Ossabaw Island swine from one of the Georgia barrier islands (in situ), and Santa Cruz Island sheep from one of the California Channel Islands (ex situ). Conservation Activities of American Live- stock Breeds Conservancy Research: The first step in any conservation effort is to identify and quantify the resources in question. Knowing what we have helps us to determine where limited conservation resources should be focused. Until very recently the United States De- partment of Agriculture has not recognized the importance of protecting the genetic di- versity in our national herds and flocks. As a result, the most important work of ALBC continues to be research of breed