A Tour de Force by Hawaii’s Invasive Mammals: Establishment, Takeover, and Ecosystem Restoration through Eradication

Scaling Up Restoration Efforts in the Pacific Islands: A Call for Clear Management Objectives, Targeted Research to Minimize Uncertainty, and Innovative Solutions to a Wicked Problem

“…In the last 30 years, progress has been made in reducing uncertainty in the field of restoration ecology by identifying effective approaches to restoration, particularly in forest and grassland ecosystems. The complete eradication of introduced ungulates, rodents, or habitat-altering plants has been accomplished on a few small islands and within conservation fencing ( Hess 2016, Judge et al 2017). However, Judge et al (2017) are quick to point out that the effort was substantial and costly, and there are considerable difficulties in scaling up to eradication efforts for entire populations on unfenced landscapes.…”

A comparison of abundance and distribution model outputs using camera traps and sign surveys for feral pigs

“…Feral pigs occupy six continents, having been intentionally introduced by humans for food provisioning and game recreation (Barrios-Garcia and Ballari 2012). They are often referred to as ecosystem engineers, fundamentally altering ecosystems through a suite of impacts on soil properties, plant and animal communities, and hydrological processes (Hone 2002;Nogueira-Filho et al 2009;Cole and Litton 2014;Hess 2016;Wehr 2018). Additionally, feral pigs negatively impact agriculture and livestock production through predation, competition, habitat disturbance and disease transmission (Gentle et al 2015).…”

Moisture availability and ecological restoration limit fine fuels and modelled wildfire intensity following non‐native ungulate removal in Hawaii

“…Hawaii is a model case study of the impacts of such non-native ungulate introductions on island ecosystems. Over the past 30 years, as a result of the documented negative impacts of non-native ungulates, management agencies in Hawaii have fenced and removed non-native ungulates from over 750 km 2 of conversation areas statewide, primarily on federally managed lands (Hess, 2016). Meanwhile, the contemporary wildfire regime in the Hawaiian Islands is characterized by a substantial increase in area burned over the past 100 years, from an average of ~800 ha/yr in the first half of the 20th century to ~8,500 ha/yr in 2005-2011(Trauernicht et al, 2015.…”

“…Ungulate activity can also indirectly impact ecosystem processes such as hydrology and nutrient cycling and, if population densities are high enough, cause severe habitat degradation, soil erosion and native species population declines (Chynoweth et al., 2013; Cole & Litton, 2014; Hobbs, 1996; Long et al., 2017; Siemann et al., 2009; Wehr et al., 2018). In response to these negative impacts, fencing and removal of non‐native ungulates is an increasingly common global strategy for conserving and restoring native biodiversity (Beever et al., 2008; Cole & Litton, 2014; Hess, 2016; Kay & Bartos, 2000; Shono et al., 2007; Spear & Chown, 2009). These efforts have been highly effective at reducing ungulate densities within management units, with important conservation benefits in most cases.…”

“…Untangling the complex interactions between non‐native ungulates and wildland fuels is important for restoring native biota and protecting ecosystem services. Domesticated cattle Bos taurus , goats Capra hircus and sheep Ovis aries , wild populations of axis deer Axis axis , and Polynesian, domestic and wild European pig mixtures Sus scrofa have been introduced to island ecosystems globally and have subsequently established non‐native populations, many over the course of centuries (Hess, 2016). Hawaii is a model case study of the impacts of such non‐native ungulate introductions on island ecosystems.…”