A recent study conducted by Shannon Grubbs, Graduate Research Assistant at the University of Arizona School of Natural Resources, and Paul Krausman, Boone and Crockett Professor of Wildlife at the University of Montana and Harris Environmental Group associate, found that Coyotes (Canis latrans) pose a risk to domestic cats (Felis catus). 8 coyotes were captured, radiocollared, and tracked from November 2005 to February 2006 for 790 hours in Tucson, Arizona, USA. The researchers observed 36 coyote–cat interactions; 19 resulted in coyotes killing cats. Most cats were killed in residential areas from 2200 hours to 0500 hours during the pup-rearing season. Single coyotes were as effective killing cats as were groups of one or more coyotes. Documented cases of predators killing cats could encourage cat owners to keep their cats indoors and assist wildlife managers in addressing urban wildlife issues.

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Safety for free-roaming pets has been a concern in some urban areas due to increasing numbers of coyotes (Canis latrans; McClure et al. 1995, Grinder and Krausman 1998) and attacks on people and their pets (Baker and Timm 1998, Timm et al. 2004). Between September 2003 and March 2007, the Arizona Game and Fish Department (AGFD) received 127 reports from citizens of Tucson, Arizona, USA, about coyotes; 14.2% (n = 18) were from people that lost a pet to a coyote or observed a coyote carrying a domestic cat (Felis catus) or dog (Canis lupus familiaris; E. Ostergaard, AGFD, unpublished data). Because coyotes are prevalent throughout Tucson (Grinder and Krausman 1998, 2001) residents are encouraged by AGFD to keep cats and small dogs indoors. The Humane Society maintains the Safe Cats™ campaign encouraging cat owners to keep cats indoors to protect them from hazards, including predators (The Humane Society of the United States 2003).

Although coyotes prey upon domestic cats, which have contributed 13.1% of the diet of coyotes (MacCracken 1982, Shargo 1988, Quinn 1997), the literature does not describe coyote–cat interactions or the group size of coyotes involved in killing cats. Our objectives were to describe the group size of coyotes involved in coyote–cat interactions, time and location of interactions, and outcomes of interactions.

STUDY AREA

Tucson, Arizona was located in eastern Pima County within the Santa Cruz River valley (Sellers and Hill 1974). Tucson encompassed approximately 587 km2 and had an estimated population of 543,587 (Department of Urban Planning and Design 2006). Average annual temperature was 20.4° C with an average annual rainfall of 32.3 cm (National Oceanic and Atmospheric Administration 2007). Tucson had a matrix of stream channels (i.e., washes) throughout the city that were dry most of the year. Washes provided a natural corridor for wildlife species and were thick with native vegetation including velvet mesquite (Prosopis velutina), white-thorn acacia (Acacia constricta), catclaw acacia (A. greggii), prickly pear cactus (Opuntia spp.), and paloverde trees (Parkinsonia spp.) that provide cover.
We trapped coyotes within the Colonia Solana (CS) and El Encanto neighborhoods and the Randolph Golf Course in central Tucson. Randolph Golf Course was adjacent to CS and separated from the neighborhood by a 2-lane road, bicycle and walking path, and a 2.5-m-high chain-link fence. A city park was also adjacent to CS. The golf course and park provided open space for coyotes. Both neighborhoods had 2–7 residences/ha. Lots in both neighborhoods included native and exotic vegetation. The wash ran through the southern end of CS.

METHODS

We used padded leg-hold traps (no. 3 Victor Soft Catch Coilspring, Lititz, PA) for 15 days in November 2005 and 7 days in February 2006 to catch coyotes. We placed traps on trails and in washes used as travel corridors by coyotes. We covered traps during the day to minimize catching nontarget animals. We restrained trapped coyotes with a noose pole and muzzle and used cable ties to hobble their legs. We fitted coyotes with radiocollars (Global Positioning System [GPS] Store-On-Board Model TGW-3402; Telonics, Mesa, AZ) and released them at sites of capture. We randomly selected coyotes to follow in 4-hour tracking sessions between 1800 hours and 1000 hours (i.e., 1800–2100 hr, 2200–0100 hr, 0200–0500 hr, 0600–1000 hr), visually located them when possible, and recorded activity (e.g., traveling, bedded, eating) by season (i.e., breeding [Jan–Feb], gestation [Mar–Apr], pup rearing [May–Aug], dispersal [Sep–Dec]). Because coyotes inhabited an urban setting they were accustomed to vehicles and pedestrians and our activity did not likely interfere with their behavior. City street lights generally provided adequate light to observe coyotes except when they were in large vacant areas, golf courses, or residents’ yards; we then used triangulation to locate coyotes. We made observations and triangulations from a vehicle. Our study protocol was approved by the Institutional Animal Care and Use Committee, University of Arizona (protocol no. 05-183).

RESULTS

We radiocollared and tracked 8 coyotes (6 M: 2 <12 months old, 4 >2 yr old; 2 F <12 months old) between November 2005 and February 2006. Seven were residents and 6 were members of one pack. Between December 2005 and November 2006 we tracked coyotes for 790 hours to obtain observations and triangulations. During this time we observed 36 coyote–cat interactions, of which 19 resulted in coyotes killing cats; killing did not occur in 17 interactions. Coyote–cat interactions occurred in residential areas (n = 33; 18 resulted in a cat-kill), one in a commercial area (no kill), and 2 in vacant lots (one resulted in a kill). Most interactions (n = 31) occurred between sunset and sunrise (16 resulted in a kill) and 5 occurred before sunset or after sunrise (3 resulted in a kill). We recorded interactions in each tracking period (i.e., 1800–2100 hr [n = 3], 2200–0100 hr [n = 10], 0200–0500 hr [n = 18], 0600–1000 hr [n = 5]) and season: breeding (3 interactions, 1 kill), gestation (2 interactions, 2 kills), pup rearing (25 interactions, 13 kills), and dispersal (6 interactions, 3 kills). The alpha male was involved with 12 cat-kills, other adults were involved with 9, juveniles with 12, and in 6 interactions we could not determine status of the coyotes. In the 17 interactions that did not result in a kill, the alpha male, other adults, juveniles, and other coyotes were involved in 2, 10, 8, and 3 interactions, respectively. We observed 45 instances of coyotes consuming prey and fruit: 19 cats (42%), 15 unidentified rodent species (33.3%), 8 lagomorphs (17.8%), 1 bird (2.2%), and in 3 observations coyotes consumed dates (6.6%). Feeding behavior of coyotes was variable when they killed cats. In 18 interactions coyotes consumed the cat and in one interaction a human disturbed the coyote, which then left without the cat. Coyote–cat interactions involved 5 coyotes/interaction: 19 interactions included single coyotes (7 kills), 10 interactions included 2 coyotes (6 kills), 2 interactions included 3 coyotes (1 kill), 3 interactions included 4 coyotes (3 kills), and 2 interactions included 5 coyotes (2 kills). When 3 coyotes (n = 7) were together at a kill they would each tear at the carcass, but when only 2 coyotes were present (n = 10) they took turns feeding. Single coyotes killed cats in 7 observations. When >1 coyote was involved in a coyote–cat interaction, cats were not killed more often than when one coyote was involved in the interaction (Fisher’s exact test, P = 0.054).

Of the 17 interactions that did not result in a cat-kill, 10 involved chasing cats (by 1–2 coyotes); 4 involved one coyote circling, batting at, or lunging at cats; 2 involved the coyote being chased by a cat (the coyote was circling the cat, which then began to chase the coyote); and the other involved a coyote that appeared to ignore the cat. The latter interaction involved a coyote, raccoon (Procyon lotor), and cat. The coyote chased the raccoon up a tree then lay down within 15 m of the cat.

DISCUSSION

When interactions involved one coyote and one cat (12 of 19 interactions), cats were killed in 7 instances. A cat could sometimes defend itself against a lone coyote, but coyotes are often in groups >2 (70% of observations; S. Grubbs, University of Arizona, unpublished data) and any cat outside is vulnerable to coyote attack. Pet safety is a concern relating to urban coyotes (Baker and Timm 1998, Grinder and Krausman 1998) but is easy to alleviate by keeping pets indoors. If all cat owners committed to keeping cats inside, then only feral cats would be available to coyotes. Recognizing the negative impact that feral cats have on wildlife and their potential to spread disease (Hawkins 1998, Patronek 1998, The Wildlife Society 2006), coyote predation on feral cats could have benefits for wildlife.

Management Implications

We recommend that pet owners keep their cats indoors. Although it is known that coyotes prey on domestic cats, documented cases might help convince cat owners of the dangers their cats face when allowed to free-roam. Documenting coyote–cat interactions could help emphasize to pet owners the importance of keeping their pets indoors and could provide guidelines for wildlife managers to address the problem.

Acknowledgments

E. Ostergaard provided data and reviewed earlier drafts of this manuscript. L. G. Fornaro, J. Melton, and H. Koeing assisted with trapping and darting. M. Rice assisted with tracking. This study was funded by the Arizona Game and Fish and Department, the Arizona Agricultural Experiment Station, and the Boone and Crockett Program in Wildlife Conservation, University of Montana.

LITERATURE CITED

1. Baker R. O., Timm R. M. 1998. Management of conflicts between urban coyotes and humans in Southern California. Proceedings of the Vertebrate Pest Conference. 18: 299–312.
2. Department of Urban Planning and Design. 2006. Tucson update. City of Tucson Department of Urban Planning and Design. . Accessed 17 May 2007.
3. Grinder M., Krausman P. R. 1998. Ecology and management of coyotes in Tucson, Arizona. Proceedings of the Vertebrate Pest Conference. 18: 293–298.
4. Grinder M., Krausman P. R. 2001. Home range, habitat use, and nocturnal activity of coyotes in an urban environment. Journal of Wildlife Management. 65: 887–898. Find this article online
5. Hawkins C. C. 1998. Impact of a subsidized exotic predator on native biota: effect of house cats (Felis catus) on California birds and rodents. Dissertation, Texas A&M University. College Station, USA.
6. MacCracken J. G. 1982. Coyote food in a Southern California suburb. Wildlife Society Bulletin. 10: 280–281. Find this article online
7. McClure M., Smith N. S., Shaw W. W. 1995. Diets of coyotes near the boundary of Saguaro National Monument and Tucson, Arizona. Southwestern Naturalist. 40: 101–125.
8. National Oceanic and Atmospheric Administration. 2007. Monthly and daily normals (1971–2000) plus daily extremes (1895–2007) for Tucson, Arizona. National Oceanic and Atmospheric Administration. . Accessed 8 Jan 2008.
9. Patronek G. J. 1998. Free-roaming and feral cats—their impact on wildlife and human beings. Journal of Veterinary Medical Association. 212: 218–226.
10. Quinn T. 1997. Coyote (Canis latrans) food habits in three urban habitat types of western Washington. Northwest Science. 71: 1–5. Find this article online
11. Sellers W. D., Hill R. H. 1974. Arizona climate 1931–1972. Second edition. University of Arizona Press. Tucson, USA.
12. Shargo E. S. 1988. Home range, movement, and activity patterns of coyotes (Canis latrans) in Los Angeles suburbs. Dissertation, University of California. Los Angeles, USA.
13. The Humane Society of the United States. 2003. A safe cat is a happy cat. The Humane Society of the United States. Washington, D.C., USA.
14. The Wildlife Society. 2006. Feral and free-ranging domestic cats. The Wildlife Society home page. . Accessed 20 Sep 2007.
15. Timm R. M., Baker R. O., Bennett J. R., Coolahan C. C. 2004. Coyote attacks: an increasing suburban problem. Proceedings of the North American Wildlife and Natural Resources Conference. 69: 1–10.