Hoyer1, Richard F., Mason1, Robert T., LeMaster1, Michael P., Moore2, Ignacio T.
Observations of Sharp-tailed Snakes (Contia tenuis) in Oregon.
1Dept. of Zoology, Oregon State Univ., Corvallis, OR; 2Dept. of Zoology, Univ. of Washington, Seattle, WA.
In an ongoing study of the Sharp-tailed Snake (Contia tenuis), in Oregon, information has been gathered from locality records, a mark and recapture field study, and captive specimens. Because a second species of Contia is now known to occur in Oregon (Hoyer, in prep.), historical locality records include both species. The two species can be recognized by significant differences in relative tail lengths and the number of ventral and caudal scales present. The earliest museum and published records of Contia are from the 1930s in Jackson and Benton counties. Contia have now been recorded in one eastern, and eleven western Oregon counties with C. tenuis occurring in all but Curry and Coos Counties. The new species is believed to occur in all western Oregon counties from Lane County south. From March 1998 through January 2000, a total of 693 C. tenuis have been captured encompassing 544 initial and 149 recapture events. Sightings of C. tenuis have occurred in all months with major peaks of availability in March through May and in October through early November. Preliminary data suggest possible recognition of three age/size classes. Initial captures were composed of 322 combined subadult/adult snakes and 222 juveniles (10 months or less in age). Reliable sex determination was only possibly for the subadult and adult snakes in which males outnumbered females 178 to 144. Mean and maximum lengths for subadult/adult females exceeded those for males. Males have proportionately longer tails than females and greater number of caudal scales whereas females have a greater number of ventral scutes.
(Reprinted here by permission of Richard Hoyer.)
The Society for Northwestern Vertebrate Biology