The Dynamics of Human and Rattlesnake Conflict in Southern California

<p>Human-rattlesnake conflict occurs when rattlesnakes are discovered in human-dominated areas and are deemed to pose an unacceptable risk to humans because of their venomous bite. In this dissertation, I investigated the nature of this conflict from the perspectives of both the behavioral and survival risks posed to rattlesnakes and the medical risks posed to humans. In the first of three studies, I investigated the effects of short- and long-distance translocation (SDT and LDT) of nuisance wildlife as a way of mitigating conflict between humans and naturally occurring Red Diamond Rattlesnakes (Crotalus ruber) near residential development in southern California. Snake activity ranges and risk of moving near human-modified areas were larger for LDT and SDT snakes than for non-translocated snakes. Snakes moved closer to human-modified areas and required translocation more often during the summer. Snakes translocated greater distances were less likely to return to human-modified areas, and translocation did not affect snake survival. In the second study, I investigated the etiology and severity of human envenomations using a retrospective review of 354 snakebite cases admitted to Loma Linda University Medical Center between 1990 and 2010. Male snakebite victims and those using alcohol or drugs were more likely to sustain bites to the upper extremity, distal to the ankle or wrist, and via illegitimate provocation of the snake. Snakebite severity was positively associated with snake size, negatively associated with patient mass, and independent of patient age, snake taxon, anatomical location of bite, legitimate versus illegitimate (provoked) bites, and time until hospital admission. Effectiveness of CroFab antivenom was similar for all southern California venomous snake taxa. In the final study, using the same medical data, I assessed the usefulness of several factors as predictors of overall snakebite severity, symptom progression, and antivenom use. Initial snakebite severity score, size of the envenoming snake, and patient mass were significant predictors. I suggested several rules of thumb that could help clinicians anticipate antivenom needs. Overall, this dissertation contributes to our understanding of the effects of mitigation translocation on rattlesnakes and the epidemiology and clinical management of venomous snakebite in southern California.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Earth and Biological Sciences

Year

2015

Author dc:creator

• Corbit, Aaron Grant

Contributors dc:contributor

• Hayes, William K.
• Brand, Leonard R.
• Bush, Sean P.
• Dugan, Eric
• Dunbar, Stephen G.
• Oberg, Kerby

• Biology
• Crotalus - California; Southern; Rattlesnakes - California; Southern; Rattlesnakes - Behavior; Human-snake encounters - California; Southern; Wildlife relocation - Environmental aspects - California; Southern
• Human-rattlesnake conflict; Human-dominated areas; Red Diamond Rattlesnakes; Human envenomation; Survival risk; Translocation

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/347

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-1348