Culture and Ecology of Chaco Canyon and the San Juan Basin

The Classic Adaptation 183Estimated Population Supported by AvaUableAgricultural LandBased on observations at historic Pueblos, Table6.2 suggests a range of acres cultivated per person.Table 6.2. Estimated acres of farm landneeded per person.Pueblo Acres PerGroup Person ReferenceHopi 3 Stephen (1930)Hopi 3 Hack (1942)Hopi 2 W. Bradfield (1971:36)Zia 1.09 White (1962:85)Zuni 1.06 Tyler (1964:xvi)Various 0.89 Jorde (1973)As A. Cully and Toll (1986) pointed out, most ofthese studies include populations that consume manydietary supplements and may not accurately reflectpast needs. Only the calculations made by Jorde(1973) included variables such as metabolic rates, ageand sex structure of the population, stature, prehistoriccultigen production, and proportion of diet. Bycombining the available acreage estimated by differentresearchers, as well as estimates by Schelberg (1982a)for the Escavada Wash and by Cully and Toll (1986)for the additional lands and the Bis sa'ani communitythat is located along the Escavada Wash, with the variousnumber of acres needed per person, Table 6.3 wasconstructed. Although there is a range in the numberof people that could be supported by agriculture, themaximum number for the canyon bottom isapproximately 4,000. With fallowing, this numberwould be reduced to 1,880 at 40 percent fallow, andto 1,567 at 50 percent fallow (Schelberg 1982a:Table12). Depending on the density of settlement along theEscavada Wash, these numbers could be increased.However, the Bis sa'ani community was presentduring the A.D. 1100s; it might have supportedgreater numbers than either Kin Klizhin or KinBineola at this time.These popUlation estimates are considerablyhigher than those derived from estimates of the availablemammalian remains (Akins 1985:403). Akinsassumed that each person needs 200 calories of proteinper day. Based on estimated rabbit and deer harvestrates for the Chacoan landscape, she calculated thatonly 702 people could have been supported usingavailable fauna from within what is now the parkboundary. By extending her range to include a lO-kmradius, 2,727 people could be supported (Akins 1985:404). This latter estimate assumes that no one livedwithin the perimeters of this larger area so thatresources wouid be avaiiabie to those in the canyon.Even if this were true, the numbers fall below severalestimates of the canyon population (see below).Using the same assumptions for caloric need,base.d on faunal reInains re..covered from excavatedsites (Table 6.4), Akins (1985:400-401) calculated thenumber of people that could have been supported. Shefound that none of the inhabitants of small house siteswould have had sufficient protein in their diet. Evenif the number of calories per day were cut in half (to100 per day), there would have been too little proteinto meet their needs. Although Akins recognized thatthere are a number of problems (such as exact lengthof site occupation and whether the site was usedintermittently), the situation seems bleak. Only forPueblo Alto did estimates come close to supporting theproposed population; here, the method for determiningthese estimates was based on data from the trashmound. When she based her calculations on othertrash areas at this site, the estimated protein waslower.There are several factors that could affect theseresults. Dried meat could have been imported. Althoughit would be easily storable and portable, itwould not be visible in the archaeological record(Akins 1985). Such meat could be acquired directlyby hunting or through trade. The presence of elk,bear, tassel-eared squirrel, snowshoe hare, and Easterncottontail, all available at a distance of 60 to 70 kmfrom Chaco Canyon, suggests that this occurred.Some deer and pronghorn could have been obtainedfrom closer locations. Fresh meat would keep throughthe time involved in foot transport from areas between16 and 32 km away, but meat would need to be concentratedif the source was at 80 km or more. Deer,