Sex, Mass, and Monitoring Effort: Keys to Understanding Spatial Ecology of Timber Rattlesnakes (Crotalus horridus)

Christopher E. Petersen, Scott M. Goetz, Michael Joseph Dreslik, John D. Kleopfer, Alan H. Savitzky

Research output: Contribution to journalArticle

Abstract

Despite large-scale population decline and geographic range contraction, Timber Rattlesnakes (Crotalus horridus) continue to occupy sites across much of eastern North America, including a diversity of habitat types. Here, our objective was to examine the influence of intrinsic and extrinsic factors on the movement and activity range of Timber Rattlesnakes in the Coastal Plain of southeastern Virginia. To do so, we analyzed the movements of 54 radio-implanted snakes over a period of 17 yr, with individuals being tracked for 1-6 yr, amounting to more than 14,000 snake locations. Consistent with previous studies, our results showed strong sexual differences in movements, with average daily and annual movements of males exceeding those of females. Mean annual movements of males were approximately 1.8 times greater than those of females, with a peak in male movements in late summer, associated with mate searching. Similarly, all estimates of activity ranges (using minimum convex polygon and kernel methods) were larger for males, with overall activity ranges approximately three times greater than for females. Gravid females had somewhat smaller movements and activity ranges than nongravid females, with early-season movements of gravid individuals to the birthing site, followed by shorter movements within that site, interpreted as serving a thermoregulatory function. The number of locations and body mass (of males) also appeared as significant factors in some models, although sex was the dominant factor in all models.

Original languageEnglish (US)
Pages (from-to)162-174
Number of pages13
JournalHerpetologica
Volume75
Issue number2
DOIs
StatePublished - Jun 2019

Fingerprint

Crotalus
timber
ecology
monitoring
gender
snakes
gravid females
snake
coastal plains
radio
population decline
polygon
summer
habitat type
coastal plain
body mass
contraction
habitats
seeds

Keywords

  • Activity range
  • Coastal Plain
  • Movement patterns
  • Radio-telemetry
  • Viperidae

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Animal Science and Zoology

Cite this

Sex, Mass, and Monitoring Effort : Keys to Understanding Spatial Ecology of Timber Rattlesnakes (Crotalus horridus). / Petersen, Christopher E.; Goetz, Scott M.; Dreslik, Michael Joseph; Kleopfer, John D.; Savitzky, Alan H.

In: Herpetologica, Vol. 75, No. 2, 06.2019, p. 162-174.

Research output: Contribution to journalArticle

Petersen, Christopher E. ; Goetz, Scott M. ; Dreslik, Michael Joseph ; Kleopfer, John D. ; Savitzky, Alan H. / Sex, Mass, and Monitoring Effort : Keys to Understanding Spatial Ecology of Timber Rattlesnakes (Crotalus horridus). In: Herpetologica. 2019 ; Vol. 75, No. 2. pp. 162-174.
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