/ Because studies estimating density of gray squirrels (Sciurus carolinensis) have been labor intensive and costly, I demonstrate the use of line transect surveys to estimate gray squirrel density and determine the costs of conducting surveys to achieve precise estimates. Density estimates are based on four transects that were surveyed five times from 30 June to 9 July 1994. Using the program DISTANCE, I estimated there were 4.7 (95% CI = 1.86-11.92) gray squirrels/ha on the Clemson University campus. Eleven additional surveys would have decreased the percent coefficient of variation from 30% to 20% and would have cost approximately $114. Estimating urban gray squirrel density using line transect surveys is cost effective and can provide unbiased estimates of density, provided that none of the assumptions of distance sampling theory are violated.KEY WORDS: Bias; Density; Distance sampling; Gray squirrel; Line transect; Sciurus carolinensis.

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We conducted an experiment on eastern fence lizards {Sceloporus iincliilatus) during August-September 1995 near Los Alamos, New Mexico, (1) to ascertain if lizards that were relocated short distances exhibited homing, (2) to investigate a possible barrier to movement, and (3) to detennine the effect of translocating individuals from a transplant area on lizards in a recipient area. We relocated 15 of an estimated population of 39 (95% CI 36-45) lizards an average distance of 46 m. Foin-teen of 15 translocated lizards returned to within 6.81 (s^ = 1.43) m of the original capture location. Movement distances did not vary (F = 0.76; 1,53 df P -0.381) between resident and tianslocated lizards during the pretreatment period and did not vary for resident (F = 2.86; 1,12 df; P -0.1166), but varied between pretreatment and posttreatment periods tor translocated (F = 14.65, 1,7 df P = 0.0065) lizards. Translocated lizards did not affect the resighting probability of resident lizards (F = 0.96; 1,14 df; P = 0.34), but this may be related to low power (1 -P = 0.15) and translocated lizards moving out of the area quickly.

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