Responding to misinformation and criticisms regarding United States cat predation estimates

Scott R Loss,Travis Longcore,Peter P Marra,Tom Will

doi:10.1007/s10530-018-1796-y

Abstract

Misinformation (or denialism), the disingenuous assertion of information contradicting overwhelming scientific consensus, increasingly poses a challenge for invasion biology. The issue of free-ranging domestic cats (Felis catus) provides an example of this misinformation: overwhelming consensus shows that cats are invasive species that impact wildlife and human health yet free-ranging cat advocates propagate misinformation about such impacts to support policies keeping cats on the landscape. These advocates also attempt to discredit peer-reviewed scientific research on cat impacts, as exemplified by the response to a high-profile paper estimating cats annually kill billions of U.S. birds and mammals (Loss et al. in Nat Commun 4:1396, 2013). Although favorably received by scientific and invasive species management communities, an effort was launched to discredit this paper by criticizing its methods, including a report commissioned by a feral cat advocacy group and a post by a feral cat blogger. These same organizations and individuals have made similar criticisms at scientific conferences and policy roundtables. Given the realized effects of this campaign in influencing invasive species policy, we here respond to these criticisms and show they are characterized by numerous errors and misrepresentations. We conclude that the criticisms are part of the broader campaign to fabricate doubt about outdoor cat impacts and stymie policies favoring removal of cats from the landscape. Because misinformation surrounding cats is emblematic of the broader issue of misinformation and denialism, this response will not only facilitate evidence-based policy for managing cats but also stimulate research and discussion into causes and impacts of misinformation in invasion biology.

Highlights

Misinformation, referred to as disinformation or denialism, increasingly poses a challenge to invasive species policy and management (Russell and Blackburn 2017; Ricciardi and Ryan 2018)
A salient example highlighting the problem of misinformation in invasion biology is the issue of freeranging domestic cats (Felis catus)
The claim that nonlethal approaches enhance cat welfare ignores that many outdoor cats live shortened and perilous lives (Barrows 2004; PETA 2018) and that they continue to transmit diseases and cause wild animal suffering through depredation (McRuer et al 2017)

Summary

Introduction

Misinformation, referred to as disinformation or denialism, increasingly poses a challenge to invasive species policy and management (Russell and Blackburn 2017; Ricciardi and Ryan 2018). The report provides a specific example for the proportion of owned cats allowed outdoors where eight literature estimates (0.66, 0.5, 0.65, 0.4, 0.43, 0.77, 0.36, 0.56) were used to derive a uniform distribution with min = 0.4 and max = 0.7 This criticism ignores that Loss et al (2013) did follow a formal statistical procedure to define many distributions; for some data-rich parameters, including the prey return rate and predation rate, distributions were based on 95% CIs calculated from values in the literature. Loss et al (2013) used several additional sources, including four peer-reviewed studies, to define the probability distribution for this parameter

Conclusions

Findings

Compliance with ethical standards