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Most human‐carnivore conflicts arise from the impact of predation on livestock. In Australian rangelands, considerable resources are allocated to constructing exclusion fences and implementing control measures to manage dingo populations for sustainable livestock enterprise. Assessing the effectiveness of these measures is crucial for justifying the investment. We used a replicated experimental design to examine the effect of landscape‐scale dingo‐proof exclusion fences (‘cell‐fencing’) on activity and population density of dingoes in the Southern Rangelands of Western Australia. We monitored dingo populations for 22–24 months across six study sites nested within a landscape of about 75,000 km2 and defined ‘fence level’ as the number of dingo‐proof fences enclosing each study site. We used camera trap capture rate (number of independent capture events per 100 trap nights) as a metric for dingo activity (including the availability of resources as other potential covariates), estimated dingo density using spatially explicit mark‐resight models, and tested the relationship between capture rate and estimated density of dingoes for each study site. Significant variation in both metrics was observed between sites and across time. Fence level and prey occurrence significantly influenced dingo activity. The annual mean dingo density estimate across study sites was below two dingoes per 100 km2 (i.e., 0.02 dingoes per km2; the maximum value believed to be compatible with small livestock) at only one study site in the first year, but it was higher across all sites during the second year of monitoring. Dingo activity correlated with estimated dingo density at only two sites, suggesting differences in dingo behaviour and detection across the six study sites. This study provides experimental evidence that camera trap capture rate is not a reliable method for assessing variations in the population size of dingoes. These results have implications for monitoring outcomes of dingo control programs across Australia. This study addresses a critical question: How reliable is the activity metric (here we used camera trap capture rate) to assess variations in population size of dingoes across diverse habitats in Australia? Through experimental evidence, we demonstrate that activity metrics can lead to inaccuracies in assessing changes in dingo population size. Our findings highlight the need to assess dingo population size from identified individuals, which is particularly relevant for effective dingo control programs across Australia.

Conservation fences are an increasingly common management action, particularly for species threatened by invasive predators. However, unlike many conservation actions, fence networks are expanding in an unsystematic manner, generally as a reaction to local funding opportunities or threats. We conducted a gap analysis of Australia's large predator-exclusion fence network by examining translocation of Australian mammals relative to their extinction risk. To address gaps identified in species representation, we devised a systematic prioritization method for expanding the conservation fence network that explicitly incorporated population viability analysis and minimized expected species' extinctions. The approach was applied to New South Wales, Australia, where the state government intends to expand the existing conservation fence network. Existing protection of species in fenced areas was highly uneven; 67% of predator-sensitive species were unrepresented in the fence network. Our systematic prioritization yielded substantial efficiencies in that it reduced expected number of species extinctions up to 17 times more effectively than ad hoc approaches. The outcome illustrates the importance of governance in coordinating management action when multiple projects have similar objectives and rely on systematic methods rather than expanding networks opportunistically. Los cercos de conservación son una acción de de manejo cada vez más común, particularmente para las especies amenazadas por los depredadores invasores. Sin embargo, a diferencia de muchas acciones de conservación, las redes de cercos se están expandiendo de manera unisistémica, generalmente como reacción a las oportunidades de financiamiento local o a las amenazas. Realizamos un análisis de vacio de la red de cercos de exclusión de depredadores en Australia al examinar la traslocación de los mamíferos australianos en relación con su riesgo de extinción. Para abordar los vacíos identificados en la representación de las especies diseñamos un método de priorización sistemática para expandir la red de cercos de conservación que incorporaban explícitamente el análisis de viabilidad poblacional y minimizaban las extinciones esperadas de las especies. La estrategia se aplicó en Nueva Gales del Sur, Australia, en donde el gobierno del estado pretende expandir la red existente de cercos de conservación. La protección existente de las especies en las áreas cercadas fue muy desigual; el 67 % de las especies sensibles a los depredadores estuvo mal representado en la red de cercos. Nuestra priorización sistemática produjo eficiencias sustanciales ya que redujo el número esperado de extinciones de especies hasta 17 veces más efectivas que las estrategias ad hoc. El resultado ilustra la importancia de la gobemanza en la coordinación de la acción de manejo cuando múltiples proyectos tienen objetivos similares y dependen de los métodos sistemáticos en lugar de expandir las redes de manera oportunista.

Installing conservation fences to prohibit feral animal access to wetlands can become a barrier for non‐target species of interest. We collected 161 turtles (Chelodina rugosa, Emydura subglobosa worrelli, Myuchelys latisternum) from twenty floodplain and riverine wetlands during post‐wet (June–August) and late‐dry season (November–December) surveys (2015–2018) in northern Australia. Wetlands were fenced (150 × 150 mm square, 1.05 m high wire mesh) or unfenced around the wet perimeter. Ninety‐seven percent of individuals caught in either fenced or unfenced wetlands had a shell carapace width greater than mesh width, of these 44 (46%) were captured inside fenced wetlands, while 50 were caught in unfenced wetlands. The remaining 35 turtles were smaller than 150 mm and would likely pass easily through fence mesh. Sixty‐five turtles partook in a fencing manipulative experiment. Turtles with carapace widths wider than mesh often successfully escaped through fences by lifting one side of their shell and passing diagonally through the mesh. In a second experiment where a piece of vertical wire (1500 × 300 mm) was removed, turtles located ‘gates' after prospecting and fitting through meshing areas that were too small to pass. Ninety‐two percent of turtles were able to locate and pass through gates, while 8% failed to locate a gate after 2 h. Gates applied every 4 m showed an 83% passage rate, every 2 m was 91%, and every 1 m was 100%. Combing field and manipulative experiments revealed that large turtles will prospect and move along a fence until they find suitable passage, which has important consequences when considering that gates could be easily retrofitted to existing sites, as well in new fencing programs, which has enormous positive conservation benefits for turtles in an already challenging and changing floodplain environment.

Understanding the exchange of individuals between wildlife populations, particularly those with naturally fragmented habitats, is important for the effective management of these species. This is of particular consequence when the species is of conservation concern, and isolated populations may be lost due to pressures from predation or competition, or catastrophic events such as wildfire. Here we demonstrate the use kinship and population structure analysis to show potential recent movement between colonies in metapopulations of yellow-footed rock-wallaby (Petrogale xanthopus Gray 1854) at two sites in the Grey Range of Queensland, and at four sites in the Gawler Ranges of South Australia. These colonies are also compared to a single colony from the Flinders Ranges, a connected landscape of rock-wallaby habitat. Using reduced representation next-generation sequencing, we acquired and filtered a set of ~ 17,000 single-nucleotide polymorphisms to examine population genetic variation, structure and relationships within populations, and also identify putative migrants. Initial STRUCTURE analysis re-confirmed each population should be considered separately. Tests of population genetic variation identify several colonies appearing to be experiencing genetic erosion, also with low calculated effective population sizes (Ne = 4.5–36.6). Pairwise comparisons of individual relatedness (relatedness coeffiecients; r) implied several contemporary movement events between colonies within both the Gawler and Grey Ranges (r > 0.125), which was then affirmed with tests for putative first generation migrants. These results are of particular note in South Australia, where threat abatement (management of key predators and competitors) may facilitate dispersion. Additionally, in Queensland, colonies are separated by anthropogenic barriers: predator exclusion fencing designed to exclude dingoes (Canis familiaris) from grazing land, which may hinder dispersal. This work highlights the usefulness of population genetics to inform management outcomes in wildlife, in this case, highlighting the need for threatened species management at the landscape level.

Installation of feral pig (Sus scrofa) exclusion fences to conserve and rehabilitate coastal floodplain habitat for fish production and water quality services remains untested. Twenty‐one floodplain and riverine wetlands in the Archer River catchment (north Queensland) were surveyed during postwet (June–August) and late‐dry season (November–December) in 2016, 2017, and 2018, using a fyke net soaked overnight (~14–15 hr) to test: (a) whether the fish assemblage are similar in wetlands with and without fences; and (b) whether specific environmental conditions influence fish composition between fenced and unfenced wetlands. A total of 6,353 fish representing twenty‐six species from 15 families were captured. There were no wetland differences in fish assemblages across seasons, years and for fenced and unfenced (PERMANOVA, Pseudo‐F < 0.589, p < .84). Interestingly, the late‐dry season fish were far smaller compared to postwet season fish: a strategy presumably in place to maximize rapid disposal following rain and floodplain connectivity. In each wetland, a calibrated Hydrolab was deployed (between 2 and4 days, with 20 min logging) in the epilimnion (0.2 m) and revealed distinct diel water quality cycling of temperature, dissolved oxygen and pH (conductivity represented freshwater wetlands), which was more obvious in the late‐dry season survey because of extreme summer conditions. Water quality varied among wetlands in terms of the daily amplitude and extent of daily photosynthesis recovery, which highlights the need to consider local conditions and that applying general assumptions around water quality conditions for these types of wetlands is problematic for managers. Though many fish access wetlands during wet season connection, the seasonal effect of reduced water level conditions seems more overimprovised when compared to whether fences are installed, as all wetlands supported few, juvenile, or no fish species because they had dried completely regardless of the presence of fences. Fencing wetlands prevents pig access on tropical floodplains, which should be positive for fish. However, though many fish access (fenced and unfenced) wetlands during wet season connection, the seasonal effect of reduced water level conditions seems to be more overimprovised compared to whether fences are installed or not, as all wetlands supported few, or no fish species because they had dried completed regardless of whether fences were present or not.

Reports estimates of native bird densities within a predator-fenced reserve at Bushy Park, New Zealand, over a 17-year period, including 14 years after the installation of the fence. Explains the methodology used to calibrate the three reintroduced species: North Island robins/toutouwai (Petroica longipes), North Island saddlebacks/ tieke (Philesturnus rufusater), and the hihi (Notiomystis cincta). Demonstrates that simple low-intensity monitoring data collected by non-experts can provide useful information on long-term trends in bird densities. Source: National Library of New Zealand Te Puna Matauranga o Aotearoa, licensed by the Department of Internal Affairs for re-use under the Creative Commons Attribution 3.0 New Zealand Licence.

Spillover effects are an expansion of conservation benefits beyond protected areas through dispersal of species that reside within. They have been well documented in marine but not terrestrial systems. To understand the effects on wildlife created by conservation fences, we explored the internal and external gradients of activity in mammal, reptile, and bird species at a conservation reserve in arid Australia that is fenced to exclude invasive rabbits (Oryctolagus cuniculus), cats (Felis catus), and foxes (Vulpes vulpes). Two methods were used: counts of animal tracks along transects on sand dunes and captures at pitfall-trapping sites. In both cases, sites were spaced at different distances from the reserve fenceline inside and outside the reserve. We recorded a range of spillover, source-sink, step, and barrier effects that combined to create a zone within and around the reserve with fence-induced species-specific wildlife gradients. Two endemic rodents but none of the 4 mammal species reintroduced to the reserve showed positive spillover effects. Barrier effects, where activity was highest close to the fence, were recorded for the feral cat and native bettong (Bettongia lesueur), species that could not breach the fence. In comparison, some reptiles and native mammal species that could permeate the fence displayed source-sink effects; that is, their activity levels were reduced close to the fence likely due to constant emigration to the side with lower density. Activity of some reptiles was lowest at sites inside the reserve and gradually increased at outside sites with distance from the fence, a gradient likely related to trophic cascades triggered by predator exclusion. Our result shows that fenced reserves can create overlapping layers of species-specific gradients related to each species’ability to permeate the fence and its varying susceptibility to threats. Managers should be aware that these gradients may extend for several kilometers either side of the fence and that not all contained species will increase in abundance. Creating wider conservation benefits may require increased fence permeability and threat reduction outside the fence. Los efectos de derrame son una expansión de los beneficios de conservación más allá de las áreas protegidas a través de la dispersión de especies que residen en su interior. Han sido bien documentados en sistemas marinos, pero no terrestres. Para entender los efectos de las vallas de exclusión sobre la vida silvestre, exploramos los gradientes internos y externos de la actividad de especies de mamíferos, reptiles y aves en una reserva de conservación en la región árida de Australia que está cercada para excluir conejos invasivos (Oryctolagus cuniculus), gatos (Felis catus) y zorros (Vulpes vulpes). Se utilizaron dos métodos: conteo de huellas de animales a lo largo de transectos en dunas de arena y captura con trampas pitfall. En ambos casos, los sitios fueron espaciados a distintas distancias dentro y fuera de la valla de la reserva. Registramos una gama de efectos de derrame, fuente-sumidero, escalón y barrera que se combinaron para crear una zona dentro y alrededor de la reserva con gradientes de vida silvestre inducidos por la valla. Dos roedores endémicos, pero ninguna de 4 especies de mamíferos reintroducidas a la reserva, mostraron efectos de derrame positivos. Los efectos de barrera, donde la actividad era mayor cerca de la valla, fueron registrados para el gato feral y la rata canguro nativa (Bettongia lesueur), especies que no pudieron franquear la valla. En contraste, algunas especies de reptiles y mamíferos nativos que pudieron permear la valla mostraron efectos de fuente-sumidero; esto es, sus niveles de actividad fueron bajos cerca de la valla probablemente debido a la emigración constante hacia el lado con menor densidad. La actividad de algunos reptiles fue menor en los sitios núcleo de la reserva e incrementaron a medida que incrementó la distancia hacia afuera, un gradiente relacionado probablemente con las cascadas tróficas desencadenadas por la exclusión de depredadores. Nuestros resultados muestran que las reservas cercadas pueden crear capas sobrepuestas de gradientes específicos relacionados con la habilidad de cada especie para permear la valla y su susceptibilidad a las amenazas. Los manejadores deber ser conscientes de que esos gradientes pueden extenderse varios kilómetros a ambos lados de la valla y que no todas las especies contenidas aumentarán en abundancia. La creación de beneficios de conservación más amplios puede requerir una mayor permeabilidad de la vallas y la reducción de amenazas fuera de la reserva. 溢出效应是指生活在保护区的物种扩散到保护区之外带来额外保护效益的现象,目前在海洋保护区已有 很多相关报道, 但在陆地生态系统中尚且没有 。 为了解保护围栏对野生动物的影响,我们在澳大利亚干旱地区 的一个保护区中探究了围栏内外哺乳动物 、 爬行动物和鸟类的活动梯度变化, 这个保护区建造围栏是为了阻挡 入侵物种穴兔 (Oryctolagus cuniculus)、 家 猫 (Felis catus) 和狐狸 (Vulpes vulpes)。 我们采用了两种调查方法 : 沿沙丘样带的动物足迹数量,以及陷阱诱捕位点的捕获情况; 两种方法都分别调查了从保护区围栏向内和向外不 同距离的位点 。 我们发现一系列的溢出效应 、 源汇效应 、 阶梯效应和屏障效应, 它们共同导致了保护区内部及 周围由围栏引起的物种特异的野生动物梯度带 。 四种重引入到保护区的哺乳动物没有正溢出效应, 但在两种特 有啮齿类动物中存在这种效应 。 在流浪猫和当地的草原袋鼠 (Bettongialesueur) 这两种不能翻越围栏的动物中 出现了屏障效应,即围栏附近动物活动最频繁的现象 。 相比之下,一些可以穿过围栏的爬行动物和原生哺乳动 物则表现出源汇效应,即在围栏附近的活动水平降低, 这可能是因为它们会不断向密度较低的ー侧迁移 。 另外, 一些爬行动物在保护区核心位点的活动强度最低,而距离核心位点越远活动強度越大, 这样的梯度可能与捕食 者排斥引发的营养级联有关 。 我们的結果表明,有围栏的保护区可以创造出与物种穿越围栏的能力和对威胁的 敏感度有关的物种特异性梯度, 并形成相互重叠的分布层 。 管理者应意识到这些梯度可能会延伸至围栏两侧数 公里处, 此外, 并不是所有被围住的物种丰度都会増加 。 为了创造更广泛的保护效益, 可能需要提高围栏的可穿 越性并减少围栏外的威胁 。

One of the deadliest roads in North America for species at risk fragments a marsh-lake ecosystem. To reduce road mortality, stakeholders installed >5 km of exclusion fencing along a southwestern Ontario, Canada, causeway in 2008–2009. Between 2012 and 2014, 7 culverts were installed to provide safe crossings. We evaluated the success of these mitigation strategies by 1) comparing results of road surveys conducted 5 years before and 5 years after fencing installation; and 2) monitoring use of culverts by turtles using motion-activated cameras at culvert openings and stationary antennas placed to detect movements of passive integrated transponder (PIT)-tagged turtles (68 Blanding’s turtles [Emydoidea blandingii] and 30 spotted turtles [Clemmys guttata]). We also radio-tracked 30 Blanding’s turtles to measure culvert use in relation to home ranges. Turtle and snake abundance was 89% and 53% lower, respectively, in completely fenced road sections than in unfenced sections; abundance was 6% and 10% higher, respectively, between partially fenced and unfenced sections. After mitigation, locations where we found reptiles on the road were associated with fence ends, underscoring the importance of fence integrity and ineffectiveness of partial fencing as a mitigation strategy. We confirmed use of culverts by Blanding’s turtles, northern map turtles (Graptemys geographica), snapping turtles (Chelydra serpentina), and midland painted turtles (Chrysemys picta). Through radio-tracking, we determined that male and female Blanding’s turtles home ranges overlapped with different segments of the causeway. We recommend that stakeholders emphasize ensuring fence integrity and continuity, limiting impact of edge effects, and conducting a comprehensive monitoring program.

Fences that exclude alien invasive species are used to reduce predation pressure on reintroduced threatened wildlife. Planning these continuously managed systems of reserves raises an important extension of the Single Large or Several Small (SLOSS) reserve planning framework: the added complexity of ongoing management. We investigate the long-term cost-efficiency of a single large or two small predator exclusion fences in the arid Australian context of reintroducing bilbies Macrotis lagotis , and we highlight the broader significance of our results with sensitivity analysis. A single fence more frequently results in a much larger net cost than two smaller fences. We find that the cost-efficiency of two fences is robust to strong demographic and environmental uncertainty, which can help managers to mitigate the risk of incurring high costs over the entire life of the project.

Invasive species are the primary threat to island ecosystems globally and are responsible for approximately two-thirds of all island species extinctions in the past 400 years. Non-native mammals-primarily rats, cats, mongooses, goats, sheep, and pigs-have had devastating impacts on at-risk species and are major factors in population declines and extinctions in Hawai'i. With the development of fencing technology that can exclude all mammalian predators, the focus for some locations in Hawai'i shifted from predator control to local eradication. This article describes all existing and planned full predator exclusion fences in Hawai'i by documenting the size and design of each fence, the outcomes the predator eradications, maintenance issues at each fence, and the resulting native species responses. Twelve predator exclusion fences were constructed in the Hawaiian Islands from 2011-2023 and six more were planned or under construction; all were for the protection of native seabirds and waterbirds. Fences ranged in length from 304-4,877 m and enclosed 1.2-640 ha. One-third of the 18 fences were peninsula-style with open ends; the remaining two-thirds of the fences were complete enclosures. The purpose of twelve of the fences (67%) was to protect existing bird populations, and six (33%) were initiated for mitigation required under the U.S. Endangered Species Act. Of the six mitigation fences, 83% were for the social attraction of seabirds and one fence was for translocation of seabirds; none of the mitigation fences protected existing bird populations. Rats and mice were present in every predator exclusion fence site; mice were eradicated from five of six sites (83%) where they were targeted and rats (three species) were eradicated from eight of 11 sites (72%). Mongoose, cats, pigs, and deer were eradicated from every site where they were targeted. Predator incursions occurred in every fence. Rat and mouse incursions were in many cases chronic or complete reinvasions, but cat and mongoose incursions were occasional and depended on fence type ( , enclosed peninsula). The advent of predator exclusion fencing has resulted in great gains for protecting existing seabirds and waterbirds, which demonstrated dramatic increases in reproductive success and colony growth. With threats from invasive species expected to increase in the future, predator exclusion fencing will become an increasingly important tool in protecting island species.