32 



86. — . 1979. Biomes of the Guadalupe Escarpment: vegetation, liz- 

 ards, and human impact. _in BIOLOGICAL INVESTIGATIONS IN THE 

 GUADALUPE MOUNTAINS NATIONAL PARK, TEXAS. Genoways, H. H. 

 and R. J. Baker, editors. National Park Service Proc. and Trans. 

 Series No. 4: if27-439. 



The vegetational basis of biome patterns in the Guadalupe Moun- 

 tains ecosystem is described. The relationship between biomes and liz- 

 ard species distribution in both grazed and ungrazed habitats is ex- 

 plored. Cnemidophorus exsanguis is characteristic of the relatively 

 mesic margins between deciduous and evergreen woodlands on canyon 

 slopes at elevations around 5500 ft. _C. inornatus is characteristic of 

 xeric shrub desert flats at 4000 ft. _C. tesselatus is abundant in the 

 more mesic succulent desert and on canyon slopes at about >4-700 ft. jC. 

 gularis and _C. tigris are scarce; the former occurs in grassland rem- 

 nants and the latter in arenaceous areas of shrub desert. _C. tessela - 

 tus is abundant throughout the temporal sequence of revegetation of a 

 pipeline construction scar in the succulent desert biome, whereas it 

 declines in grazed habitats versus protected ones in this biome. There 

 are no differences in _C. exsanguis populations between grazed and un- 

 grazed habitats in evergreen woodland. Evidence indicates that C_. tig - 

 ris and _C. septemvitta tus replace each other from shrub desert through 

 succulent desert transitions in the Big Bend region of Texas, and 

 therefore, by implication, _C. tesselatus does not compete successfully 

 with either and is relegated to marginal habitats (i.e. canyons, which 

 can be considered disturbed areas). 



87. Germano, D. 3. and C. R. Hungerford. 1981. Reptile population 

 changes with manipulation of Sonoran Desert shrub. GREAT BASIN NA- 

 TURALIST 41(1): 129-138. 



Cnemidophorus sonorae and C. tigris gracilis were among the 

 species studied on the Santa Rita Experimental Range in Pima County, 

 Arizona. Desert grasslands in the southwestern United States have 

 been invaded by mesquite during the last 100 years. _C. tigris popu- 

 lations were significantly lower in mesquite-free habitats versus 

 undisturbed mesquite and mesquite with clearings. _C^. sonorae popu- 

 lations were significantly higher in mesquite-free and mesquite with 

 clearings habitats than in undisturbed mesquite. There are indications 

 of differential use of the mesquite with clearings habitats by the two 

 species. 



88. Glass, B. P. and H. A. Dundee. 1950. Cnemidophorus tesselatus 

 (Say) in Oklahoma. HERPETOLOGICA 6(2): 30. 



Specimens were collected in the Oklahoma panhandle at an elevation 

 of 4400 feet in canyons in pinyon-juniper associations. 



