ARTICLE REVIEW
Elizondo’s et al. article “Using trail camera to estimate free-ranging domestic cat abundance in urban areas” (2016) primary goal was to demonstrate that trail cameras and sight-resight analysis is a good choice for estimating the abundance of free-ranging cats in urbanized landscapes. Secondarily, they sought to investigate if cat abundance predictably rose with a higher urbanized area. They asserted that quantifiable abundance estimates could assist when and where to put cat population management into place. And these estimates could then measure if the management practices are reducing populations as intended.
To address the analysis of urbanized landscapes, three categories of study site were chosen, high urban density, medium urban density, and low urban density, in the city of Stillwater, OK. Five sites were selected in each category meeting the constraints of the study meeting spacing requirements, avoidance of trap-neuter-return (TNR) areas, and property owners’ permission. A total of 15 trail cameras was set up over a two-month period with three secondary three-day studies, for a total of 135 trap days-nights. Each camera was infrared, which gave the best results in identifying cats, and baited with tuna. The cat’s presence triggered the camera, which captured four photos, 3 seconds apart.
Their primary findings indicate that the use of trail cameras provides a reliable method to individually identify cats with a 95.65% identification rate of 47 different cats. However, the findings did not demonstrate a difference in free-ranging cat abundance of urban landscape intensity or human density populations. [see figure 1 – (b) ANOVA modeling shows no significant comparisons]
Figure 1
The study shows that trail cameras are a useful tool for measuring individual cats, especially when our current estimates of free-ranging cats are speculative, with a diverse range of numbers. Providing a way to measure cat populations in the United States systematically is a crucial tool to capture sound data that enforces the need for management practices. This study’s most significant limitation lies in the limited sample size of camera trapping sites and a limited urban area such as Stillwater. There was not enough data to statistically examine causes of variation, like urban densities. With a more extensive study, one could potentially obtain a larger dataset to reveal cat abundances’ relationships to urbanized areas. Within field methodology, one weakness noticed was limited photo triggering. More photos could be taken to reduce unusable images where cats were moving too fast to identify by using a larger memory card. The last observation was how TNR release points were avoided, and no TNR cats were observed, which are identifiable by their ear-tips, which are cut before release back into the wild. The study was likely to be on the low end for population estimation by avoiding these clustered release areas. In the future, measuring neutered cats at different distances from the TNR colonies could provide information on TNR’s management practice, and if it indeed is resulting in population decreases.
Summary:
Elizondo’s et al. article “Using trail camera to estimate free-ranging domestic cat abundance in urban areas” (2016) demonstrates that trail cameras and sight-resight analysis are good choices for estimating the abundance of free-ranging cats in urbanized landscapes with a 95.6% identification rate of individual cats.