Predation and Risk Behaviors of Free-Roaming Owned Cats in Auckland, New Zealand via the Use of Animal-Borne Cameras

Abstract

Free-roaming cats are at increased risk of injuring themselves as well as other domestic and fauna species, yet relatively little is known about the frequency at which risk and predation behaviors occur in a typical day. In this study, cat risk, and predation behavioral information was collected using animal-borne video cameras and global positioning system (GPS) units that were attached to break-free cat collars. The observation period was one to three consecutive days for 37 convenience sampled free-roaming owned cats in Auckland, New Zealand. Video footage was manually reviewed and all predation and risk behavior events were recorded. These included stalking, pursuing, and seizing prey as well as altercations with other cats, ingesting harmful substances, and venturing into hazardous locations such as roads and storm drains. During the observation period, 23 of the 37 cats (62.2%) engaged in a total of 121 predation events. Of these, 40 resulted in successful prey capture with 18 of the 40 captures involving New Zealand native fauna species. Invertebrates were the most common taxa preyed upon ( n = 55; 46%), followed by skinks ( n = 8; 7%). No mammalian, avian or amphibian prey were captured and no cat took prey back to their residence. A total of 326 risk behaviors were observed for 32 out of the 37 cats (86.5%) with the most common being cats venturing onto the road ( n = 132; 41%). Younger cats (aged 1–6 six years) engaged in significantly more predation and risk behaviors than older cats (aged 7 years and above). Sex, breed, number of cats in a household, and geographic location were not found to be predictors of cats' participation in predation or risk behaviors. Given the high frequency of predation and risk behaviors in free-roaming owned cats, it may be beneficial to educate owners about strategies to minimize risk such as housing them indoors, containing them to their properties or monitoring their time spent outdoors.

We need to worry about Bella and Charlie: the impacts of pet cats on Australian wildlife

“…Of those Australian cats that roam, an average of 78.4% bring prey back to their owner's house (across 10 studies; Tables 1, S1); this is likely to be an underestimate, because some cats hunt (and kill) without returning prey (e.g. Bruce et al 2019). To estimate the overall predation rates of pet cats, we need to discount cats that are contained, and discount roaming cats that do not hunt; thus, the total population of 3.77 million pet cats is reduced to a minimum of 2.10 million roaming and hunting pet cats.…”

“…We used Australian studies to derive the proportion of contained cats because the extent of cat containment varies markedly among countries (e.g. 3% of cats in the UK, 10% of pet cats in New Zealand, and around 30% of cats in the USA are contained; Bruce et al 2019). We also used Australian studies to estimate the percentage of roaming cats that hunt, in case differences in pet care and prey availability across countries affect this figure.…”

Management practices of dog and cat owners in France (pet traveling, animal contact rates and medical monitoring): Impacts on the introduction and the spread of directly transmitted infectious pet diseases

“…The problem is the same for dogs roaming freely even if the proportion of dogs having this opportunity was very limited in our study. Such investigations would require other tools, such as GPS devices (Brookes et al., 2018; Bruce et al., 2019; Dürr & Ward, 2014; Hudson et al., 2019; Laager et al., 2018; Loyd et al., 2013; Meek, 1999; Molloy et al., 2017; Sparkes et al., 2014).…”

“…Moreover, contact rates between cats when they are roaming freely depend on social organization, which is linked to resource availability (Turner & Bateson, 2014). Very few studies assess such contact data and are based only on use of animal‐borne cameras (Bruce et al., 2019; Loyd et al., 2013). In France, both data on outdoor access and opportunities given to dogs and cats to roam freely, and data about dog walks are either scarce or unavailable.…”

Reduction of free-roaming cat population requires high-intensity neutering in spatial contiguity to mitigate compensatory effects

“…As suggested by Boone (2015), limiting such resources might be combined with TNR to reduce carrying capacity along with the reduction in population size (76). Despite population reduction, neutered cats might continue to hunt (77, 78). Therefore, TNR is not an effective means by itself for preventing predation.…”