Population survey and management strategies of free-roaming dogs (Canis familiaris) on Saipan, Commonwealth of the Northern Mariana Islands

ABSTRACT

The island of Saipan, Commonwealth of the Northern Mariana Islands, is populated by free-roaming dogs who were introduced during World War II. The local nonhuman animal control agency manages this population; however, the demographic information and public perception of this population remain unknown. To characterize the free-roaming dog population, an island-wide survey on Saipan was conducted. Photographic, mark-recapture data were used to estimate the population size per land type. Age, sex, sociality, and behavior per land type were documented and associations between these variables were tested using G tests. The effects of land type and urbanization on dog abundance were also analyzed. Lastly, in-person surveys provided data on the public perception of free-roaming dogs. Four main findings are reported: (a) The population size of free-roaming dogs on Saipan is estimated at 21,316. (b) Most dogs encountered were sentry adults. (c) Dog abundance increased with urbanization level and was highest in urban areas. (d) The public perceived free-roaming dogs as a health concern and suggested the implementation of leash laws and sheltering initiatives. This article discusses potential and existing population management strategies for free-roaming dogs on Saipan.

KEYWORDS:

• Canis familiaris
• introduced species
• population structure
• spatial distribution
• public perception

Acknowledgments

The authors appreciate the help and support of the Commonwealth of the Northern Mariana Islands (CNMI) Division of Fish and Wildlife (including Director Manny Pangelinan, Marvin Pangelinan, Jay Camacho, and Jesse Hapadei); the CNMI Department of Land and Natural Resources (including state forester Victor C. Deleon-Guerrero, Jr.); the Asia Pacific Academy of Science Education and Environmental Management; KKMP Radio Broadcasting Station; the Humane Society International (including Andrew Rowan and Kelly Coladarci); and the Humane Society of the United States (including Inga Gibson, Dave Pauli, and John D. Boone) for their support. Special thanks to Saipan Mayor Donald Flores, Thomas Borja, Silke Buschmann, Bethany Gray, and the Northern Arizona University Field Experience in Conservation Biology 2012–2013 participants (including Sarah Hottel, Michael Marshall, Jordan Pletzer, Johnna Eilers, Erica “Rosie” Alling, Monique Brown, Brittani Bulger, Karah Roof, Natalie Senini, and Sarah Raber) for their assistance with research. Thanks to the Northern Marianas College Environmental and Natural Resources Organization (including Severino Alforeza III, Lee Roy Sablan, Tom Pangelinan, and Julius Reyes) for help with data collection. Thanks to Natasha Jones and Alanneh Nimer for their continued support. Comments from anonymous reviewers significantly improved this manuscript.

Conflicts of Interest

The authors declare no conflict of interest.

Additional information

Funding

This work was funded in part by the Northern Arizona University Go Scholarship and Global Opportunities Scholarship.