Assessing public support for restrictions on transport of invasive wild pigs (Sus scrofa) in the United States

Characterizing feral swine movement across the contiguous United States using neural networks and genetic data

Globalization has led to the frequent movement of species out of their native habitat. Some of these species become highly invasive and capable of profoundly altering invaded ecosystems. Feral swine (Sus scrofa × domesticus) are recognized as being among the most destructive invasive species, with populations established on all continents except Antarctica. Within the United States (US), feral swine are responsible for extensive crop damage, the destruction of native ecosystems, and the spread of disease. Purposeful human-mediated movement of feral swine has contributed to their rapid range expansion over the past 30 years. Patterns of deliberate introduction of feral swine have not been well described as populations may be established or augmented through small, undocumented releases. By leveraging an extensive genomic database of 18,789 samples genotyped at 35,141 single nucleotide polymorphisms (SNPs), we used deep neural networks to identify translocated feral swine across the contiguous US. We classified 20% (3364/16,774) of sampled animals as having been translocated and described general patterns of translocation using measures of centrality in a network analysis. These findings unveil extensive movement of feral swine well beyond their dispersal capabilities, including individuals with predicted origins >1000 km away from their sampling locations. Our study provides insight into the patterns of human-mediated movement of feral swine across the US and from Canada to the northern areas of the US. Further, our study validates the use of neural networks for studying the spread of invasive species.

Private Landowners' Perspectives on Feral Swine and Regulation-Evidence from Arkansas, Louisiana, and East Texas

Feral swine (FS) (Sus scrofa) are an invasive species that has spread widely across the southern United States, including the West Gulf region. With their rapidly increasing population, they have caused severe damage to landowners. To better understand private landowners' knowledge and attitudes toward FS, we conducted a mail survey in the West Gulf region including Arkansas, Louisiana, and East Texas in 2021. The results indicated that the majority of landowners are familiar with, have overall negative opinions of, and are concerned about the presence and future population growth of FS in this region. Nearly 70% of the private landowners surveyed supported stricter FS control regulations. Logistic regression results further revealed that landowners' supportiveness for FS control regulations is associated with their perceived FS-induced economic damage and ownership characteristics (i.e., age and tenure). These findings shed new light on private landowners' perspectives on FS invasions and control regulations, aiding in developing and implementing FS control/management policies and programs in the West Gulf region and beyond.

Cultural and regulatory factors influence distribution and trajectory of invasive species in the United States: A wild pig case study

Since 2012, control of invasive wild pigs (Sus scrofa) in the United States (US) has become a state and national priority due to their propensity to damage agricultural commodities and infrastructure, transmit disease, detrimentally affect ecological processes, and compete with native wildlife for resources. While several life-history characteristics certainly aided their proliferation, the recreational value of wild pigs was likely the stimulus for translocation and subsequent establishment of populations in ≥35 states, causing an annual economic burden of $1.5 billion in the US. Consequently, state-level legislative procedures regarding wild pigs are expanding in scope and priority, but policy among states lacks uniformity. States vary in their treatment of wild pig control based on differing resource appropriations and stakeholder interests. We conducted an evaluation to determine if policy was associated with state-level 1) presence of wild pigs, 2) spatial extent of wild pig population occupancy, and 3) trajectory of wild pig population occupancy. Our results suggest the presence of wild pigs in various states was influenced by hunting preserves and the sale of hunting opportunities. In occupied states, the spatial extent of wild pigs was again associated with the sale of hunting opportunities and a wild pig hunting culture. Finally, the trajectory of state-level wild pig spatial occupancy was positively influenced by the sale of hunting opportunities, and negatively influenced by transportation policies. Based on these findings, we propose state governments standardize transportation policy and fenced hunting regulations across regions of the US in a more prohibitive fashion to diminish range expansion through illegal and negligent introductions via transportation, release, and escapes from game farms. Moreover, in states where wild pigs have yet to establish, we strongly recommend states proactively prohibit transportation through intra- and interstate movement.

Understanding tolerance for an invasive species: An investigation of hunter acceptance capacity for wild pigs (Sus scrofa) in Texas

Invasive species and their establishment in new areas have significant impacts on the ecological, economic, and social well-being of our planet. Wild pigs (Sus scrofa) are one of the world's most formidable invasive species, particularly in the United States. They cause significant damage to agriculture and ecosystems, and can transmit diseases to livestock, wildlife, and people. There is an inherent social dimension to the issue of wild pigs due in part to the fact that people hunt them. Hunting contributes to both the control and spread of this species. The objectives of this study were to: 1) determine hunters' overall tolerance for wild pigs; and 2) identify what factors predict hunters' tolerance. Results obtained from a survey of Texas hunters in 2019 indicated that 83% of hunters had a low level of tolerance for wild pigs, with approximately 63% preferring to see the population reduced and 20% preferring to see the population completely removed. Fourteen percent preferred that wild pig numbers remain the same, and 2% preferred to see numbers increase. Results from regression analysis indicated that approximately 53% of the variance in tolerance for wild pigs was explained by motivations and preferences for hunting wild pigs, level of concern for wild pig damage, and overall attitudes toward wild pigs. Results of this research are useful in expanding current knowledge about human tolerance for wildlife, including those species that are non-native and invasive, and in identifying important factors affecting how hunters perceive and interact with wild pigs. Study findings are also helpful in informing the development of effective and socially acceptable management plans for wild pigs, as well as communication efforts aimed at influencing hunters' attitudes and behaviors in the wild pig management context.

Chinese Resident Preferences for African Elephant Conservation: Choice Experiment

Despite passionate efforts to preserve African elephants worldwide, their numbers continue to decline. Some conservation programs have suspended operations because the funds provided by various governmental and non-governmental organizations (NGOs) cannot cover the enormous expenses of countering poaching, habitat destruction, and illegal ivory trading. This study investigates Chinese resident preferences for African elephant conservation using a choice experiment model. Results indicated that two-thirds of our 442 respondents with relatively higher education and income levels were willing to donate to conserve African elephants. Respondents were willing to donate RMB 1593.80 (USD 231.65) annually to African elephant conservation. Chinese residents were willing to donate the most to anti-poaching RMB 641.25 (USD 93.20), followed by enhancing habitat quality RMB 359.07 (USD 52.22), combating the illegal trade in ivory RMB 355.63 (USD 51.69), and alleviating human–elephant conflicts RMB 237.85 (USD 34.57). Our results suggest that accepting public donations could be an efficient way for NGOs to better preserve African elephants.

Public Preferences and Willingness to Pay for Invasive Forest Pest Prevention Programs in Urban Areas

Invasive forest pests can cause environmental and economic damage amounting to billions of dollars (US) in lost revenues, restoration and response costs, and the loss of ecosystem services nationwide. Unfortunately, these forest pests do not stay confined to wildland forest areas and can spread into suburban and urban areas, imposing significant costs on local governments, homeowners, and management agencies. In this study, a contingent valuation experiment is used to estimate Florida residents’ willingness to pay (WTP) a monthly utility fee that would protect urban forests from invasive pests by implementing a monitoring and prevention program for their early detection and eradication. On average, the respondents are WTP US $5.44 per month to implement the surveillance program, revealing an aggregate WTP in the order of US $540 million per year. The results also reveal that respondents are sensitive to the scope of the program, with higher rates of participation and higher WTP for a program that is more effective at preventing forest pest invasions.