What Is a Feral Cat? a Case Study of Legislative Definitions for Hawaiian Monk Seal Conservation M.E.M. Capstone Experience Fina
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What is a feral cat? A case study of legislative definitions for Hawaiian monk seal conservation Photo credit: NOAA Fisheries M.E.M. Capstone Experience Final Report Author: Vaibhavi Dwivedi May 5, 2021 NREM 695/696 – Spring 2021 Committee Members: Dr. Mahealani Kaneshiro, Dr. Travis Idol, & Dr. Creighton M. Litton What is a Feral Cat? CONTENTS Abstract .…………………………………………………………... Page 3 Introduction …………………………………………………………… Page 4 Motivation …………………………………………………………… Page 5 Objectives …………………………………………………………… Page 6 Materials & Methods .……...…………………………………………………… Page 7 Discussion & Results ..………………………………………………………… Page 10 Conclusions ..………………………………………………………… Page 21 References ..………………………………………………………… Page 23 Appendix ………………………………………………………… Page 26 Dwivedi 2 What is a Feral Cat? Abstract The spread of toxoplasmosis (toxo) from the feces of feral cats is a leading cause of mortality for the endangered Hawaiian monk seal (Monachus schauinslandi). To date, 12 monk seals in the main Hawaiian islands (MHI) and one seal in the North Western Hawaiian Islands (NWHI) have died from toxo in the last two decades. Given an estimated total population of ~1400 monk seals of which ~300 are currently found in the MHI, the number of seals that have succumbed to toxo highlight a significant threat to this critically endangered population. With approximately 300,000 feral cats living on the Island of O‘ahu alone, the potential severity of this deadly infection spreading to the Hawaiian monk seal population is high. To better manage the large and growing feral cat population, it is imperative that a uniform definition of ‘feral cat’ be implemented by the State of Hawaiʻi to inform the development and implementation of management policies across the state. The objectives of this project were to: (i) analyze feral cat definitions used in Hawaiʻi, (ii) compare Hawaiʻi’s feral cat management approaches with other U.S. states, New Zealand, and Australia, and (iii) draft legislative recommendations for defining feral cats in Hawaiʻi to serve as the basis of effective management policies. Sources for data collection for the first two objectives included extensive literature review from peer-reviewed journals, policies, and legislations. A 10-point rank system was created to analyze the effectiveness of existing definitions and policies. As a secondary output, a user-friendly website, ‘HICat’, was created to increase outreach and support long-term goals of this research. If implemented in Hawaiʻi, a uniform feral cat definition has the potential to set strong precedent for other island states to incorporate in their localized conservation strategies. Keywords: Endangered Species, Toxoplasmosis, Invasive Species Management Dwivedi 3 What is a Feral Cat? Introduction The spread of toxoplasmosis from the faeces of feral cats is a leading cause of Hawaiian monk seal mortality (Barbieri, 2016). Toxoplasmosis infections are caused by the microscopic parasite, Toxoplasma gondii, which can only sexually reproduce in cat intestines. The parasite’s eggs are introduced to the marine environment when cat faeces enter waterways (NOAA, 2020). They are then unintentionally consumed by monk seals via egg-laden (contaminated) seawater or prey. Once infected, toxoplasmosis may cause organ failure by tissue decay of muscles, liver, heart, or brain leading to fatalities (Barbieri, 2016). In the last two decades, at least 12 monk seals have died from toxoplasmosis disease in the Main Hawaiian Islands (MHI) and one in the North Western Hawaiian Islands (NWHI) (NOAA, 2020). Since seal carcasses may not always be found or may not be in good enough condition for postmortem testing, the current number of monk seal deaths due to toxoplasmosis disease is likely an underestimation. With an estimated population of ~300 seals in MHI, this infectious disease has resulted in the fatality of 4.3% of the MHI monk seal population since 2000. The National Oceanic and Atmospheric Administration (NOAA) has identified feral cats as the primary source of T. gondii eggs. With an estimated feral cat population of ~300,000 on O‘ahu alone (Hawaiian Humane Society, 2017), the mismanagement of feral cats is a significant threat to the Hawaiian monk seal population (NOAA, 2020). On a broader scale, management of feral cats is also essential for conservation of other endangered and endemic species found on islands (Oppel, Steffen, et al., 2014). In addition to the spread of toxoplasmosis, feral cats are well documented hunters of endemic birds (Nogales et al., 2013) (Appendix B). Known for being the ‘super-predator’ in the trophic network of islands (Fitzgerald, 1988), feral cats have driven numerous extinctions of endemic vertebrates on islands (Veitch, 2001). This makes the Hawaiian Islands especially vulnerable to increasing conservation issues that stem from hosting a large number of feral cats. Given the sufficient scientific evidence that links eradication and management of feral cats to the rapid comeback of endangered native species across various islands worldwide (Nogales et al., 2013), it is necessary to manage feral cat populations in Hawai‘i. This is not only crucial to curb the spread of toxoplasmosis, but also to promote Hawai‘i’s endemic and endangered species conservation efforts. Dwivedi 4 What is a Feral Cat? Motivation An important aspect of the mismanagement of feral cats in Hawai‘i stems from shortcomings in feral cat policies. With no definitive methods or organizations responsible for distinguishing outdoor pet cats from feral cats in Hawai‘i, feral cat management strategies are complex. Fostering free-roaming or stray cats in open spaces locally further complicates feral cat management practices (Hart and Hart, 1998). Developing management policies regarding feral cats, their caregivers, and imposing sanctions for illegal activities, respectively, require a legal definition of feral cats. Current feral cat management in Hawai‘i utilizes non-specific definitions of what constitutes a ‘feral cat’. The Hawai‘i Invasive Species Council (HISC) describes feral cats as ‘identical to the common pet cat and are actually the same species separated only by lifestyle and behavior. Feral cats may utilize human resources or live completely independently and can be found in all types of habitat, including free-ranging in the mauka lands’ (2018). However, this definition has not been uniformly adapted for management purposes. The state of Hawai‘i devolves authority to create and implement management policies to the counties, however, the county level regulations remain inconsistent. For example, Honolulu County law does not define feral cats, and instead provides legislative directions which mandate cat owners to neuter pets before allowing them to be ‘at large’ (ROH § 7-6.6). This does not aim to tackle the increasing population of feral cats and instead legally permits people to let their pet cats roam outdoors and be at large without any liability. Thus, in the absence of a uniform and legally binding definition of different categories of cats, it is difficult to implement effective management policies. Some of the major organizations that work towards promoting effective feral cat management in Hawai‘i include NOAA, Department of Land and Natural Resources (DLNR), American Bird Conservancy, and Island Conservation. The discrepancy in using a uniform statewide definition of a feral cat results in lack of consistency and creates challenges for policy development and implementation. Therefore, determining a uniform definition for a feral cat will support current legislative decision-making, including but not limited to, amendments in the county legislations. Stakeholders involved in feral cat management include legislators, policymakers, invasive species managers, endangered species conservationists, and cat owners. Distinguishing the various categories of cats starts with compiling information on existing definitions and policies regarding feral cat management. Dwivedi 5 What is a Feral Cat? Objectives The specific objectives of this paper are to i) analyze feral cat definitions used in Hawaiʻi, (ii) compare Hawaiʻi’s feral cat management approaches with other U.S. states, New Zealand, and Australia, (iii) draft legislative recommendations for defining feral cats in Hawaiʻi to serve as the basis of effective management policies. A secondary output of this research is to launch a public website that is readily available and easy to navigate, which may improve outreach to support the long-term goals of this project that include generating awareness on this issue (Appendix A). Dwivedi 6 What is a Feral Cat? Materials and methods 1. Data Sources 1)Wildlife and veterinary medical journals that regularly publish systematic reviews (Google Scholar, Jstor, Hein Online, West Law); 2) Legislative bills and case laws; 3) Books by wildlife control consultants & other scholars; 4) Online News articles; 5) Informal interviews with experts in the field (telephonic); 6) Presentations in toxo workshop (in-person). Australia and New Zealand were chosen because of the similarities between conservation challenges associated with endemic and endangered biodiversity found within their territories and in Hawai‘i. New Zealand is particularly similar to Hawai‘i as it is an island chain with no native felids or other predators. The impact of feral cats on their native biodiversity was also considered before the selection of sources. Information from these jurisdictions were specifically chosen from official state