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Questions: Oceanic islands are global hotspots of endemism and evolutionary radiations but many have been severely degraded by human activities and biological invasions. We evaluated the pace and direction of the natural recovery of ecosystems over 77 years across a subtropical oceanic archipelago including islands of various size, elevation, histories of human settlement and deforestation, and invasions by non‐native plants and mammals. This information is essential to guide the ecological restoration of the archipelago. Location: Forest vegetation on nine of the Ogasawara Islands in the northwestern Pacific Ocean. Methods: We first digitized historical vegetation data of the Ogasawara Islands collected during field surveys in 1935. Then, after checking their species compositions, we integrated past and present plant community types. Finally, we identified the landscape‐scale changes in forest vegetation by comparing vegetation maps from 1935, 1979 and 2012. Results: Over 77 years, the vegetation trajectories of each island varied depending on the introduction of invasive alien species and the remaining proportion of native forest, the latter of which had a strong influence on the recoverability of native forest. Conclusions: Our results highlight the importance of the history of invasive species introductions and the remaining proportion of native forest—both of which reflect the intensity of anthropogenic disturbance—in determining the degree of human intervention needed for restoration on oceanic islands. [ABSTRACT FROM AUTHOR]

Little is known of insect biodiversity on Isla Guadalupe, a large (c. 250 km2) Pacific island located off the west coast of Baja California, Mexico, which has undergone more than 150 years of extensive habitat degradation owing to grazing by feral goats. Goats were successfully eradicated in 2007, and thus Isla Guadalupe provides a rare opportunity to study changes in biodiversity in the flora and fauna as the habitat in this isolated geographic region begins to recover. We conducted a preliminary survey of Lepidoptera biodiversity by collecting and observing mainly adult individuals during July–August, 2019. We also included previous observations from 2003–2016, and two historical records dating back to 1874 and 1922. Our annotated inventory includes 31 species of Lepidoptera (10 species of butterflies from four families, and 21 species of moths from seven families), and includes one butterfly species recorded 100 years ago that we did not find and which may be extirpated. Although life history stages were not recorded (except for the cosmopolitan Vanessa cardui), we also comment on the availability of potential larval host plants based on literature records from other regions. Most of the Lepidoptera species in our inventory (n = 22) have also been recorded from at least one of the comprehensively studied Channel Islands in southern California, USA, and all 31 species are also present on the California mainland. Thus, the Lepidoptera fauna on Isla Guadalupe recorded here corresponds to that associated with Californian Biogeographic Province. [ABSTRACT FROM AUTHOR]

Soil erosion after vegetation degradation induced by disturbance by feral goats, an invasive mammal, can lead to loss or accumulation of soil at a local scale and can alter soil chemical properties. This alteration of soil properties can in turn affect the establishment of plant species. We evaluated relationships among the extent of soil erosion, soil chemical properties, and the distribution of plant species in grassland ecosystems after goat eradication on Nakodo‐jima Island in the northwestern Pacific. In 105 1 × 1–m quadrats, changes were measured in the position of topsoil over 2 years. Surface soils were sampled for analysis of chemical properties, and plant species in the quadrat were recorded. Changes in the position of topsoil were related to the area of bare ground. Soil loss occurred at sites where areas of bare ground were extremely large. Significantly higher values of soil exchange acidity and smaller amounts of available phosphorus, total carbon, and total nitrogen were detected in soils at sites with large soil losses. Most of the 11 dominant plant species were absent from sites with large losses of soil. The presence of eight species was significantly negatively related to soil exchange acidity, and three species were significantly positively related to available phosphorus. Our results indicated that exposure of subsoils at the soil surface after vegetation degradation can increase soil loss, which can alter soil chemical properties, and this alteration can continue to limit the establishment of plant species, even long after goat eradication. [ABSTRACT FROM AUTHOR]

An interview-based questionnaire survey was conducted on 31 goat properties in New South Wales and Queensland in 2013. This study has gathered information on goat herd management, reproductive performance and animal health, and has identified constraints that may limit goat productivity. Producers from high-rainfall regions reported having full blood Boer goats for stud breeding. In contrast, producers from pastoral regions had rangeland goats and Boer-cross goats. Overall, 87% of the producers identified a natural breeding season in goats and 61% separated kids from their mothers at weaning. The weaning age varied between 3.0 and 6.0 months. A total of 52% of producers castrated male kids. Only 10% of producers used ultrasound to conduct pregnancy diagnosis on their goats. The reported pregnancy rate was 60% for the pastoral regions and 94% for the high-rainfall regions. The average prolificacy was 1.4 kids/doe and the kidding interval was 12 months. Overall, 68% of producers fed their goat herd with supplements, with the exception that most producers from western New South Wales and south-western Queensland did not use supplements. Producers considered gastrointestinal parasites (61%) and body lice (48%) as the main diseases associated with their goat herds, although only 52% mentioned drenching the animals with anthelmintics. In general, properties in the pastoral regions showed low pregnancy and kidding rates, early age at first mating, high mortality rates, poor performance of Boer bucks and lower weights and weight gain compared with properties in the high-rainfall regions. The survey has highlighted areas that require further study to validate the observations of producers, for instance, factors that may be limiting the fertility of Boer goats in rangeland environments, the incidence of diseases, the use of Kidplan and management activities to improve goat productivity. [ABSTRACT FROM AUTHOR]

This study aimed to survey farmers' knowledge and practices on the management of pastures, stocking rates and markets of meat goat-producing enterprises within New South Wales and Queensland, Australia. An interview-based questionnaire was conducted on properties that derived a significant proportion of their income from goats. The survey covered 31 landholders with a total land area of 567 177 ha and a reported total of 160 010 goats. A total of 55% (17/31) of producers were involved in both 'opportunistic harvesting' and commercial goat operations, and 45% (14/31) were specialised seedstock producers. Goats were the most important livestock enterprise on 55% (17/31) of surveyed properties. Stocking rate varied considerably (0.3-9.3 goats/ha) within and across surveyed properties and was found to be negatively associated with property size and positively associated with rainfall. Overall, 81% (25/31) of producers reported that the purpose of running goats on their properties was to target international markets. Producers also cited the importance of targeting markets as a way to increase profitability. Fifty-three percent of producers were located over 600 km from a processing plant and the high cost of freight can limit the continuity of goats supplied to abattoirs. Fencing was an important issue for goat farmers, with many producers acknowledging this could potentially add to capital costs associated with better goat management and production. Producers in the pastoral regions appear to have a low investment in pasture development and opportunistic goat harvesting appears to be an important source of income. [ABSTRACT FROM AUTHOR]

Many introduced species can co-exist within the same ecosystem and sometimes interact with each other. Under such situations, eradication of one species may cause unexpected negative effects. Nakoudo-jima in the Ogasawara (Bonin) Islands is an oceanic island that had feral goats that were introduced in the 1880s, but eradicated in 1999. Following their eradication, the alien invasive shrub Leucaena leucocephala (Fabaceae) was predicted to increase drastically. In this study, we tested the hypothesis that the eradication of feral goats enhanced the expansion of L. leucocephala using four time-series aerial photographs and validation work based on current field surveys of Nakoudo-jima. Our results showed that following feral goat elimination, bare ground areas decreased and forest cover increased. This was particularly true of areas dominated by L. leucocephala. Thus, feral goats appear to have limited the expansion of L. leucocephala on Nakoudo-jima. Grassland cover also increased following feral goat elimination, but this may have occurred prior to L. leucocephala expansion. These results suggest that L. leucocephala-dominated forest might invade grassland areas and that grasslands may have mediated the expansion of L. leucocephala after feral goat elimination. Future management of L. leucocephala should target the species in the high-risk expansion zones adjacent to grasslands. [ABSTRACT FROM AUTHOR]

Eradication is often the preferred method of invasive species management on islands; however, its consequences may affect native communities. Feral goats ( Capra hircus), donkeys ( Equus asinus), and pigs ( Sus scrofa) were eradicated from Santiago Island in the Galapagos Archipelago by 2005. Because feral goats were the dominant herbivores on Santiago Island until their eradication, we examined the consequences of goat eradication on the diet of territorial Galapagos Hawks ( Buteo galapagoensis) through a comparative study of observations of prey deliveries to nests before (1999-2000) and after (2010-2011) eradication. We predicted that vegetation recovery after eradication would limit the hawks' hunting success of terrestrial prey and they would therefore switch to predominantly arboreal prey. We did not observe the predicted switch from terrestrial to arboreal prey in the diet; on the contrary, after goat eradication, hawks delivered significantly fewer arboreal prey items. However, introduced black rats ( Rattus rattus) represented a significantly greater proportion of the hawks' diet after eradication, particularly in moderate to dense vegetation (arid and transition habitats), replacing other prey items. Overall, 73% of total prey biomass delivered after eradication consisted of introduced rats, compared to only 20% before eradication. This study documents the complex interaction of predators and introduced prey, even in relatively simple ecosystems. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the trophic behaviour and the social structure of Majorcan wild goats and feral goats present in the island of Majorca. The former are descendants of an ancestral goat ecotype introduced in the island in the late Neolithic, whereas feral goats come from domestic forms introduced recently from the Iberian Peninsula. The study was conducted in four localities of the Serra de Tramuntana, a mountain range located in the northwest of the island of Majorca. Behavioural data were collected in three seasons, summer, winter and spring of 2011–2013, and when goat activity is at its peak, i.e., 3 h after dawn and before dusk. The following variables were recorded: group composition (males, females, and kids) and activity (feeding, walking, resting, and watching). The proportion of time spent on each activity and their frequency were obtained from focal samples. Multivariate analyses of variance (MANOVA) were used to simultaneously analyse the activity variables. A total of 155 observations of 85 herds were registered throughout the study. A similar behaviour pattern has been observed in this study for the two goat ecotypes, feral and wild, apart from some seasonal variations in feeding and resting activities. In summer, feral goats showed higher feeding efforts (duration and frequency) than wild goats; this might be related to a lower efficiency obtaining feeding resources by the former, whereas wild goats, that have inhabited the island for millennia, coexisting with vegetation in periods of lower forage abundance and quality, would be more efficient herbivores during restrictive periods. Average herd size for both ecotypes is smaller than that recorded for domestic goat herds, suggesting a relatively low browsing damage compared to the latter. Also, feral goats apparently have a higher gregarious behaviour than wild ones, which might relate to their domestic origin. Currently, the management of goats on the island is based on maintaining the wild ecotype and eradicate the feral one, whose impact on vegetation is supposedly worse. However, our results show a similar trophic behaviour by both ecotypes, so that their impact on vegetation should also be expected to be similar, indicating that this argument has not enough scientific basis. [ABSTRACT FROM AUTHOR]

Advances in wildlife telemetry and remote sensing technology facilitate studies of broad-scale movements of ungulates in relation to phenological shifts in vegetation. In tropical island dry landscapes, home range use and movements of non-native feral goats (Capra hircus) are largely unknown, yet this information is important to help guide the conservation and restoration of some of the world’s most critically endangered ecosystems. We hypothesized that feral goats would respond to resource pulses in vegetation by traveling to areas of recent green-up. To address this hypothesis, we fitted six male and seven female feral goats with Global Positioning System (GPS) collars equipped with an Argos satellite upload link to examine goat movements in relation to the plant phenology using the Normalized Difference Vegetation Index (NDVI). Movement patterns of 50% of males and 40% of females suggested conditional movement between non-overlapping home ranges throughout the year. A shift in NDVI values corresponded with movement between primary and secondary ranges of goats that exhibited long-distance movement, suggesting that vegetation phenology as captured by NDVI is a good indicator of the habitat and movement patterns of feral goats in tropical island dry landscapes. In the context of conservation and restoration of tropical island landscapes, the results of our study identify how non-native feral goats use resources across a broad landscape to sustain their populations and facilitate invasion of native plant communities. [ABSTRACT FROM AUTHOR]

We tested whether vegetation recovery on an oceanic island after the eradication of feral goats is related to disturbances by goats and recovery of seabird nesting in an island. To test, we investigated relationships among the aboveground biomass of herbaceous vegetation, nutrient concentrations in the soil after goat eradication, and vegetation degradation before goat eradication and seabird nesting after the eradication. The investigation was conducted on the island of Nakoudojima, a subtropical island situated in the northwestern Pacific Ocean with consideration of fine-scale variation of topography and structure of current vegetation. The aboveground biomass of herbaceous vegetation was correlated with the presence of vegetation degradation before goat eradication but not with seabird nesting after eradication. Concentrations of carbon and nitrogen in the soil were correlated with both the presence of vegetation degradation and seabird nesting. The concentration of available phosphorus in the soil was correlated with nesting seabirds but not with vegetation degradation. The presence of nesting seabirds was correlated with differences in dominant species in the vegetation after goat eradication and with topography. Our results suggested that fine-scale heterogeneities of the aboveground biomass of herbaceous vegetation and the concentrations of nutrients in the soil after goat eradication in an island could be related to vegetation degradation and subsequent erosion of surface soil caused by goats and seabird nesting after the goat eradication. [ABSTRACT FROM AUTHOR]

This study examined the recovery, via biotic and abiotic pathways, of a grassland ecosystem after eradication of introduced exotic goats. We used path analyses to evaluate the relative strength of relationships among aboveground biomass, soil chemical properties (carbon, nitrogen, and phosphorus content; soil acidity), presence of nesting seabirds after goat eradication, extent of vegetation degraded by goats before their eradication, plant species composition after removal of goats, and topography. Models including the same variables with different paths were constructed using the Bayesian estimation method, and the best-fit models were constructed by comparing deviance information criterion values. Results of the path analyses demonstrated that vegetation degradation and soil erosion prior to goat eradication increased soil exchangeable acidity, which resulted in limitation of aboveground biomass. Seabird nesting after goat eradication increased the quantity of soil nutrients, possibly through inputs of feces, eggshells, and dead chicks or adults. The increase in nutrients was affected indirectly, via seabird nesting, by topography and vegetation type after goat eradication. The direct and indirect relationships demonstrated by our results suggest the existence of complex interrelationships during recovery of ecosystem function after eradication of exotic mammals. [ABSTRACT FROM AUTHOR]

The feral Goat ( Capra hircus) has successfully exploited a range of landscapes around the world with occurrences of overabundance resulting in significant damage to ecological values. In forested ecosystems in Australia, there are currently limited means to control the species when compared to the range of management techniques available for other pest animals. To redress this deficiency, we designed a feed structure combined with commercially available salt blocks to attract goats to set locations in a forested study area. Structures that exploited differences in the pedal morphology (foot size and shape) of native herbivores (kangaroos and wallabies) and ungulates (feral goats and deer) were found to be highly target-specific, with feral goats freely able to access salt blocks, whilst nontarget native species were effectively excluded. Other introduced ungulate species, Fallow Deer ( Dama dama) and Red Deer ( Cervus elaphus), successfully accessed salt blocks in feed structures but at a considerably lower rate than feral goats. The capacity to present a range of bait types within a target-specific feed structure, once matched with a humane toxicant, could provide land managers with an additional cost-effective lethal control tool for future management of feral ungulates, particularly goats. [ABSTRACT FROM AUTHOR]

We carried out a pilot study about the influence of the domestic goat Capra hircus on the feeding ecology of the Iberian ibex Capra pyrenaica in the Peneda-Gerês National Park (PGNP, Portugal). We mapped the grazing areas of domestic goat flocks and determined their stocking rates in two mountains of PGNP, Gerês and Amarela, and we investigated the diets of both ungulates using fecal microhistology in an area where they partially overlapped during spring and summer. Diet composition, ligneous diversity, and ligneous trophic niche were compared seasonally. Although differences in ligneous components were observed, results revealed a considerable diet overlap mainly due to graminoids consumption, especially during autumn and spring. This suggests that direct or indirect foraging competition between the goat species should not be discarded if they spatially concur. Results also emphasized distinct summer feeding strategies of C. pyrenaica in the area, and the influence of cattle (Bos taurus) and horses (Equus caballus) were hypothesized. We recommend removing feral goats from the mountain environment and monitoring grazing areas of domestic flocks. Estimates of ecological carrying capacity and future diet studies should include cattle, horses, and improvement of herb identification. [ABSTRACT FROM AUTHOR]

Question Hurricanes are a major factor influencing forest structure and have been linked to higher incidences of multiple-stemmed trees in Caribbean dry forests relative to the continent. In Sept 1998, category 3 Hurricane Georges passed over Mona Island. This island, unlike others in the Caribbean, has had feral goats for five centuries. In this study we addressed the following questions: (i) what are the short-term (4 mo) and long-term (10 yr) responses of Mona Island's dry forests to hurricane disturbance in terms of forest structure and tree mortality; and (ii) is there any effect of goat exclusion on the recovery process and forest structure after the hurricane? Location Dry forest of Mona Island, Puerto Rico. Methods Permanent fenced and unfenced plots established in 1997 and monitored annually until 2008 were used to evaluate the interplay between goat herbivory and hurricane effects on structural dynamics of the tree community. Within these plots, vegetation data collected include species identity, DBH, successional status and hurricane-related tree mortality. Results We found that vegetation responses to hurricane disturbances may have been influenced by the presence of feral goats through at least two mechanisms. First, goats may have led to changes in forest structure and composition that feed back into the recovery dynamics that follow hurricane events. Second, goat herbivory limits the production of multiple stems, a trait that could be an adaptive response in hurricane-prone areas. Feral goats may lead to alternate successional pathways by keeping this dry forest at early-successional stages much longer than expected, and shifting vegetation communities to an alternate state where smaller, shrubbier and perhaps less palatable species dominate. Conclusions Differences in structure between Mona Island's dry forest and other tropical dry forests are related to changes in species composition that may have been triggered by introduced goats. Our results highlight the potential complexities that may arise when setting management goals within the context of novel ecosystems. Ultimately, implementation of management goals requires knowing what changes are linked to the ecological integrity of the ecosystem and what cultural values are placed on the current state of the tree community vs its historical condition. [ABSTRACT FROM AUTHOR]

Invasive browsing ungulates can have strong impacts on the structure and composition of forest ecosystems, particularly where ungulates are not native ecosystem components as in New Zealand. Ungulate impacts on plant communities have been considered mostly from an above-ground perspective. However, understanding below-ground effects of these invasive herbivores is critical as they may drive feedbacks to above-ground ecosystem components., We measured growth responses of seedlings of five common tree species in a greenhouse experiment in soils collected from 26 plots fenced to exclude invasive ungulates for at least 17 years and from paired, unfenced control plots. We then further investigated soil-mediated effects of ungulates on one tree species, Melicytus ramiflorus, by partitioning these effects into soil abiotic and biotic components, as well as measuring arbuscular mycorrhizal fungal ( AMF) root infection., Biomass of seedlings of all five species was greater in soils from within exclosures, although this was only significant for two species. These soil-mediated effects were partially driven by changes in physical and chemical soil properties; soil bulk densities were lower inside exclosures than in controls., Effects of invasive ungulates on seedling biomass of M. ramiflorus were positively related to effects on per cent AMF root infection. The biomass of M. ramiflorus seedlings was positively related to the AMF infection of its roots, which in turn was related to greater organic matter content and lower bulk density of soils from within exclosures. Results for M. ramiflorus indicated that soil-mediated effects of ungulates on seedling biomass were of abiotic origin, but were mediated by the biotic soil component, that is, through effects on AMF., Synthesis. Invasive herbivores may potentially impact on plant performance and community structure not only directly but also indirectly through influencing soil abiotic and biotic properties. Our results show that shifts in plant-soil interactions and feedbacks represent important but understudied pathways by which invasive ungulates can have wide-ranging impacts on forest ecosystems. Future studies should consider the importance of soil-mediated effects of invasive ungulates relative to direct effects of herbivory. [ABSTRACT FROM AUTHOR]

The feral goats from Tankwa Karoo National Park in the Northern Cape, South Africa, constitute a potentially unique goat population, which dates back to the early 1900s, but is now at risk of extinction. A total of 66 feral goats from Tankwa Park and former Tankwa goats, now kept on a private farm were genotyped, using eight microsatellite markers. The data were compared with genotypic data of selected commercial breeds (Angora, Boer and Saanen dairy goats). Analysis of population structure using Bayesian and frequency-based methods suggests some uniqueness in the Tankwa populations. This uniqueness may reflect decades of random drift, but could also reflect alleles for adaptation to a harsh environment resulting from natural selection. These results are the first for the Tankwa goat and provide essential information for compiling a strategy for conservation and breeding of this genetic resource. [ABSTRACT FROM AUTHOR]

In January 2000, the last Pyrenean wild goat, Capra pyrenaica pyrenaica, died in Ordesa National Park in the Spanish Pyrenees. Since that time, there has been an intense debate over the possibility of using individuals from other extant subspecies to restore the Iberian wild goat C. pyrenaica in the Pyrenees. In the late 1990s, some Iberian wild goats of the hispanica subspecies escaped from an enclosure in Guara Nature Park, also in the Spanish Pyrenees. Between 2006 and 2012, four annual counts were conducted to quantify the demographics of the population. This expanding but isolated population numbered at least 86 free-living Iberian wild goats in 2012, reproducing in the wild with a positive increasing trend (λ=1.067). Given the small number of original animals that escaped, new releases are necessary to insure the genetic variability of the small population, but only if a clear decision on its conservation is finally made. In addition, the population is sympatric with a population of several hundred feral goats, C. hircus, which should be monitored closely, in order to detect any problems with competence or hybridization, although the latter has not been demonstrated in the wild. [ABSTRACT FROM AUTHOR]

We conducted a time series analysis using the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data product over the Alcedo volcano region of Isabela Island in the Galápagos to determine vegetation changes before, during, and after a feral goat invasion and eradication project. Enhanced vegetation index (EVI) values for the Alcedo region of Isabela Island were analysed from 2000 to 2010 with respect to the presence of a large population of goats that was eradicated between 2004 and 2006. This study finds large-scale, seasonal vegetation pattern changes between 2000 and 2005, and 2005 and 2010. Statistically significant EVI decreases prior to and during eradication in zones where goats were present in high numbers and increases following eradication in zones with lower goat density are found. EVI appears to have changed little over the entire study period, though earlier imagery would likely reveal stronger positive post-eradication trends. Because EVI primarily reveals greenness and little about vegetation composition and structure, we find that long-termin situvegetation monitoring is also needed to obtain a meaningful assessment of the effects of invasion and eradication at the species level. [ABSTRACT FROM PUBLISHER]

Domestic goats, Capra hircus, were intentionally introduced to numerous oceanic islands beginning in the sixteenth century. The remarkable ability of C. hircus to survive in a variety of conditions has enabled this animal to become feral and impact native ecosystems on islands throughout the world. Direct ecological impacts include consumption and trampling of native plants, leading to plant community modification and transformation of ecosystem structure. Although the negative impacts of feral goats are well known and effective management strategies have been developed to control this invasive species, large populations persist on many islands. This review summarizes impacts of feral goats on Pacific island ecosystems and management strategies available to control this invasive species. [ABSTRACT FROM AUTHOR]

Efforts to eradicate nonnative mammals to restore oceanic island ecosystems have become increasingly successful but parallel tracking of response by native species for which control efforts are intended to benefit has been rare. A major campaign to eradicate nonnative goats and burros was initiated in 1995 on Alcedo Volcano in the Galápagos Archipelago that ultimately removed 62,868 goats and eliminated them by 2006. Planners of the eradication program had the foresight to invest in intensive monitoring of the status of the volcano's giant tortoise ( Chelonoidis nigra) population whose welfare was a primary motivation for the eradication effort. Monitoring revealed an increase in the proportion of juveniles among all tortoises as well as increased growth rates of individual tortoises on Alcedo Volcano from earlier to later phases of the eradication campaign. Over the same time frame in a control population on nearby Santa Cruz Island (where goats and donkeys were not removed) juvenile fraction and individual growth rates remained unchanged. Although goat removal coincided with occurrence of a rare climatic event that simultaneously boosted forage availability for tortoises, failure to observe a comparable improvement in the control population implies that removal of goats and burros was the primary causative factor of improving population status of tortoises on Alcedo Volcano. [ABSTRACT FROM AUTHOR]

We use data on feral goats on the Isle of Rum to explore the hypothesis that time is a major constraint on the latitudinal and altitudinal distribution of this species. Daylength and temperature were the principal factors influencing the main time budget elements (feeding, moving and resting). Because the goats do not feed at night due to low ambient temperatures, they faced particular problems during winter when daylengths were at their shortest. A mean monthly windchill-adjusted temperature of 5°C appeared to be a critical threshold in terms of the animals' ability to survive on Rum. We used these data to model the animals' time budgets at different latitudes and altitudes. We show that winter daylength would be shorter than the required feeding time north of about 60° latitude, with a narrowing altitudinal cone approaching sea level at this latitude. Biogeographic evidence confirms that feral goat populations are not self-sustaining north of this latitude. [ABSTRACT FROM AUTHOR]

The article offers information on Feral Goats (Capra hircus) which is mammal brought to Great Britain in Neolithic time as domestic stock along with its anatomy. Topics discussed include anatomy of Feral Goats which include rings on the horns with characteristic markings on its body and face; appearance which suggests evidence of cross breeding; wild populations of Feral Goats in Britain and Ireland; and provision of increased milk and meat by Feral Goats.

Animals have co-evolved with mutualistic microbial communities, known as the microbiota, which are essential for organ development and function. We hypothesize that modern animal husbandry practices exert an impact on the intestinal microbiota. In this study, we compared the structure of the fecal microbiota between feral and domestic goats using the G2 PhyloChip and assessed the presence of five tetracycline resistance genes [tet(M), tet(S), tet(O), tet(Q) and tet(W)] by PCR. Feces were collected from 10 goats: 5 domestic from a farm in the main island of Puerto Rico and 5 feral from the remote dry island of Mona. There were 42 bacterial phyla from 153 families detected in the goats' feces. A total of 84 PhyloChip-OTUs were different in the fecal microbiota of feral and domestic goat. Both feral and domestic goats carried antibiotic resistance genes tet(O) and tet(W), but domestic goats additionally carried tet(Q). Diet, host genetics and antibiotic exposure are likely determinant factors in shaping the intestinal microbiota and may explain the differences observed between feral and domestic goats fecal microbiota. [ABSTRACT FROM AUTHOR]

Abstract: Feral goats (Capra hircus) are ubiquitous across much of Australia''s arid and semi-arid rangelands, where they compete with domestic stock, contribute to grazing pressure on fragile ecosystems, and have been implicated in the decline of several native marsupial herbivores. Understanding the success of feral goats in Australia may provide insights into management strategies for this and other invasive herbivores. It has been suggested that frugal use of energy and water contributes to the success of feral goats in Australia, but data on the energy and water use of free-ranging animals are lacking. We measured the field metabolic rate and water turnover rate of pregnant and non-pregnant feral goats in an Australian rangeland during late summer (dry season). Field metabolic rate of pregnant goats (601±37kJkg−0.73 d−1) was 1.3 times that of non-pregnant goats (456±24kJkg−0.73 d−1). The water turnover rate of pregnant goats (228±18mLkg−0.79 d−1) was also 1.3 times that of non-pregnant goats (173±18kg−0.79 d−1), but the difference was not significant (P =0.07). There was no significant difference in estimated dry matter digestibility between pregnant and non-pregnant goats (mean ca. 58%), blood or urine osmolality, or urine electrolyte concentrations, indicating they were probably eating similar diets and were able to maintain osmohomeostasis. Overall, the metabolic and hygric physiology of non-pregnant goats conformed statistically to the predictions for non-marine, non-reproductive placental mammals according to both conventional and phylogenetically independent analyses. That was despite the field metabolic rate and estimated dry matter intake of non-pregnant goats being only 60% of the predicted level. We suggest that general allometric analyses predict the range of adaptive possibilities for mammals, but that specific adaptations, as present in goats, result in ecologically significant departures from the average allometric curve. In the case of goats in the arid Australian rangelands, predictions from the allometric regression would overestimate their grazing pressure by about 40% with implications for the predicted impact on their local ecology. [Copyright &y& Elsevier]

Recent archaeological investigations on Cyprus have unveiled unsuspected Late Glacial and Early Holocene (twelfth-tenth millennia cal BP) pieces of the island's human history. Based on a review of the archaeological data and of the final results of the archaeozoological analyses of Sector 1 of the prepottery site at Shillourokambos, this paper examines how Cyprus improves our understanding of the process of mammal domestication in the Near East. Early introduction of controlled wild animals and then of early domestic lineages provides information about the modalities of the domestication process on the mainland. This information emphasizes the importance of technical skills, of local opportunities and adaptations, and of long-distance and increasing exchanges in the larger Near East area. Cyprus was a recipient of wild or domestic taxa from the continent through recurrent introductions, but it was fully part of the wider area of incipient farming, as seen in local innovations such as the intensive hunting/control of wild deer and boar or local domestication of wild/feral goats. The transition to farming during the tenth millennium appears to follow an unstable and opportunistic Early and Middle Pre-Pottery Neolithic B phase of low-level food production based on rapidly changing combinations of hunting, control, and breeding. [ABSTRACT FROM AUTHOR]

Invasive alien mammals are the major driver of biodiversity loss and ecosystem degradation on islands. Over the past three decades, invasive mammal eradication from islands has become one of society's most powerful tools for preventing extinction of insular endemics and restoring insular ecosystems. As practitioners tackle larger islands for restoration, three factors will heavily influence success and outcomes: the degree of local support, the ability to mitigate for non-target impacts, and the ability to eradicate non-native species more cost-effectively. Investments in removing invasive species, however, must be weighed against the risk of reintroduction. One way to reduce reintroduction risks is to eradicate the target invasive species from an entire archipelago, and thus eliminate readily available sources. We illustrate the costs and benefits of this approach with the efforts to remove invasive goats from the Galápagos Islands. Project Isabela, the world's largest island restoration effort to date, removed >140,000 goats from >500,000 ha for a cost of US$10.5 million. Leveraging the capacity built during Project Isabela, and given that goat reintroductions have been common over the past decade, we implemented an archipelago-wide goat eradication strategy. Feral goats remain on three islands in the archipelago, and removal efforts are underway. Efforts on the Galápagos Islands demonstrate that for some species, island size is no longer the limiting factor with respect to eradication. Rather, bureaucratic processes, financing, political will, and stakeholder approval appear to be the new challenges. Eradication efforts have delivered a suite of biodiversity benefits that are in the process of revealing themselves. The costs of rectifying intentional reintroductions are high in terms of financial and human resources. Reducing the archipelago-wide goat density to low levels is a technical approach to reducing reintroduction risk in the short-term, and is being complemented with a longer-term social approach focused on education and governance. [ABSTRACT FROM AUTHOR]

Hata K, Suzuki J-I & Kachi N (2010). Fine-scale spatial distribution of seedling establishment of the invasive plant, Leucaena leucocephala, on an oceanic island after feral goat extermination. Weed Research 50, 472–480. On oceanic islands, native vegetation disturbed by feral goats has been invaded by an alien shrub, Leucaena leucocephala, after goat removal. We investigated how the distribution of L. leucocephala at the earliest stages of invasion was related to the distance from seed sources and the structure of the herbaceous vegetation. At a fine spatial scale in Nakoudojima Island, Japan, an oceanic island in the western Pacific, we calculated correlations between the presence of L. leucocephala and its distance from a forest dominated by L. leucocephala, the height of the herbaceous vegetation, and the depth of litter accumulation. The occurrences of L. leucocephala plants smaller than 1.3 m in height were negatively correlated with distance from L. leucocephala forest, the height of the herbaceous vegetation, and litter depth. On the other hand, the occurrence of plants larger than 1.3 m in height was correlated only with distance from L. leucocephala forest. Our results suggested that the distribution of smaller individuals of an alien plant at specific sites would be related not only to the distance from its seed sources, but also to the structure of the herbaceous vegetation. [ABSTRACT FROM AUTHOR]

Many previous studies have found that as group size increases, individual vigilance levels decrease and forage intake increases (group-size effect), but few such studies have considered the impact of within-group interactions and other confounding factors on the direction of group-size effects. A free-ranging population of feral goats ( Capra hircus), with little predation threat, was studied on the Isle of Rum (northwest Scotland), from Jun. to Nov. 2000, to investigate the effects of group size on individual vigilance levels and foraging efficiency after taking into account the effect of confounding factors (e.g. sex, season, time of day, habitat, predation risk) and within-group interactions (via changes in movement rates while feeding). Our results show that, while group size exerted a negative influence on individual vigilance levels and a positive effect on movement rate, foraging efficiency never increased with group size and even decreased at certain times of day. There was no sex difference in individual vigilance in feral goats, but foraging efficiency was higher in females than in males. Goats were more vigilant in fall than in summer. The results imply that the benefits for foraging obtained from the reduced vigilance level in larger groups may be constrained or offset by increased interaction (or competition) within larger groups even in a population that faces negligible predation risk. [ABSTRACT FROM AUTHOR]

Invasive mammals are premier drivers of extinction and ecosystem change, particularly on islands. In the 1960s, conservation practitioners started developing techniques to eradicate invasive mammal populations from islands. Larger and more biologically complex islands are being targeted for restoration worldwide. We conducted a feral goat (Capra hircus) eradication campaign on Santiago Island in the Galápagos archipelago, which was an unprecedented advance in the ability to reverse biodiversity impacts by invasive species. We removed .79,000 goats from Santiago Island (58,465 ha) in <4.5 years, at an approximate cost of US$6.1 million. An eradication ethic combined with a suite of techniques and technologies made eradication possible. A field-based Geographic Information System facilitated an adaptive management strategy, including adjustment and integration of hunting methods. Specialized ground hunting techniques with dogs removed most of the goat population. Aerial hunting by helicopter and Judas goat techniques were also critical. Mata Hari goats, sterilized female Judas goats induced into a long-term estrus, removed males from the remnant feral population at an elevated rate, which likely decreased the length and cost of the eradication campaign. The last 1,000 goats cost US$2.0 million to remove; we spent an additional US$467,064 on monitoring to confirm eradication. Aerial hunting is cost-effective even in countries where labor is inexpensive. Local sociopolitical environments and best practices emerging from large-scale, fast-paced eradications should drive future strategies. For nonnative ungulate eradications, island size is arguably no longer the limiting factor. Future challenges will involve removing invasive mammals from large inhabited islands while increasing cost-effectiveness of removing low-density populations and confirming eradication. Those challenges will require leveraging technology and applying theory from other disciplines, along... [ABSTRACT FROM AUTHOR]

1. Many species of wildlife are harvested for sale but there are few time-series analyses of the factors determining the number of animals harvested. Economic theory predicts that price paid per animal is likely to be an important determinant of the harvest, but prices paid for alternative activities could reduce the harvest, and environmental factors such as rainfall could either constrain or enhance the harvest. 2. About 1 million feral goats Capra hircus L. are commercially harvested annually in the semi-arid rangelands of Australia, and there is much interest in how the harvest can be maximized so that the environmental impacts of the goats are minimized. 3. We developed 27 candidate models to explain monthly variation in the numbers of feral goats commercially harvested in Western Australia during July 1988 to June 2003. We fitted linear AR(1) models to the first 89 months of data and used Akaike's Information Criterion corrected for small sample size to identify the model(s) with substantial support. We then evaluated how much variation in the latter 88 months of the time series each model explained. 4. Almost 2·9 million feral goats were harvested in the study period. The two models with substantial support accounted for 70·5% and 70·6% of variation in the number of feral goats harvested during the first 89 months and 64·6% and 66·7% of variation in the subsequent 88 months. The models both included month of harvest and negative effects of rainfall in both the month of harvest and the previous month. One of the models also included a strong positive effect of the Australian Consumer Price Index-adjusted average price paid per feral goat on the number of feral goats harvested, and this model had the most support when fitted to the entire time series. 5. Synthesis and applications. This is the first study to demonstrate how both an environmental factor (rainfall) and an economic factor (average price paid per animal) can influence the size of a commercial wildlife harvest. Whilst managers can seldom modify environmental factors, our results suggest that the size of a wildlife harvest can be manipulated by altering the economics of the harvest. [ABSTRACT FROM AUTHOR]

One of the greatest threats to native biodiversity is attributable to the invasion of habitats by alien species. In particular, feral animals can be some of the most aggressive and damaging introduced species in the natural environment, especially on isolated islands. Rapid growth of the feral goat population on Alcedo volcano, one of six volcanoes on the largest of the Galapagos Islands, Isabela, was first noted in 1991. Feral goat impacts on other islands in the archipelago have caused extensive degradation of native and endemic vegetation driving plant and animal species and subspecies to extinction or to the brink of extinction. Effective management of these feral herbivores demands knowledge of intensity and range of the areas that are being most heavily impacted. A time-series analysis of AVHRR NDVI 10-day maximum value composite datasets corresponding to the goat-infested area and a control area where relatively few goats exist spanning the period of 1992-1996 were analysed according to local seasonality. Statistically significant reductions in NDVI values for vegetated areas in the study area relative to the control area were detected, which was tested against fieldwork surveys. This study suggest that analysis of 1 km2 resolution AVHRR data may provide a cost-effective means to evaluate the location and extent of vegetation impacts exerted by feral herbivores grazing in areas too remote for regular, comprehensive field observations. [ABSTRACT FROM AUTHOR]

Sexual segregation is common in ungulates. We show, in a high latitude population of feral goats where behavioural synchrony and fission rates have been shown to be the best explanation for segregation, that it is differences explicitly in the feeding time requirements of the two sexes (but not those for other activities) that best explains the variations in monthly frequencies of segregation. However, this effect is less marked during winter months when short day length forces the time budgets of the two sexes to converge. We argue that the various explanations for segregation can best be interpreted as separate factors in a multivariate model in which species- and habitat-specific weightings influence the relative importance of these variables, and thus the likelihood that segregation will occur. [ABSTRACT FROM AUTHOR]

Abstract: Helicopters are commonly used for managing wildlife populations, but their effect on wildlife behaviour is poorly understood and often ignored by managers. Changes in behaviour can adversely affect wildlife, compromise assumptions of survey methods, and reduce the effectiveness of management operations. In this study, we investigated the behavioural responses of free-ranging feral goats to helicopters and the main determinants of alert behaviour in response to helicopters. Ground-based reporters made 784 observations of feral goat groups during 34 standardised helicopter surveys used to estimate abundance. Feral goats were often alert (44% of observations) and, in 31% of observations, moved (up to 1.5km) in response to helicopter over-flights but no feral goats were observed to be injured nor did any post-partum females desert their young in response to over-flights. Regression analyses indicated that the distance from the helicopter and prior activity were the most important factors influencing the extent of alert behaviour and the distance moved in response to helicopter disturbance. The responses of herds of goats in different home ranges were variable, and cumulative survey time, type of helicopter and the density of herds also influenced behavioural responses. Results indicated that, while long-term effects of helicopter disturbance on feral goat behavioural ecology are minimal, short-term changes in behaviour frequently occur and should be considered when using helicopters to manage feral goats. [Copyright &y& Elsevier]

Abstract: The aim of this experiment was to examine how an increased number of animals per feeding place and type of roughage affected feeding time, feed intake and the level of aggressive competition in groups of dairy goats. We conducted a 3×2 factorial experiment with type of roughage (hay or grass silage) and number of goats per feeding place (1, 2 or 3) as the main factors. A total of 48 female goats in mid lactation was randomly divided into eight groups of six animals (mean age 3.7 years). The goats were video recorded for 24h at the end of each experimental period, and activity variables such as feeding, queuing, standing/walking and lying were scored using instantaneous sampling with 10min intervals. All incidents of social interactions were scored continuously for 6h between 09:00 and 15:00h. Individual goats from each group were ranked as high, medium or low according to the number of times they were displaced (physically or passively) from the feed barrier by another goat. Percentage of total observations spent feeding decreased (P <0.0001) and % of total observations spent queuing (P <0.0001) increased with increasing number of goats per feeding place. Silage intake also decreased with 16.2% from one to three goats per feeding place (P <0.001), but no such effect was found on hay. The reduced feeding space resulted in more than 80% reduction in feeding time for some individuals. The number of displacements at the feed barrier (P <0.05) and aggressive interactions (P <0.05) increased with an increasing number of goats per feeding place, and the aggression level was higher when offered hay than silage (P <0.0001). Low ranked goats spent significantly less % of total observations feeding (P <0.01) and more % of total observations queuing (P <0.05) than goats in medium and high rank categories, and this effect became more pronounced as the number of goats per feeding place increased. In conclusion, an increased number of goats per feeding place resulted in a lower % of feeding observations, a larger % of total observations spent queuing, and an increased number of aggressive interactions for both types of roughages. The level of aggressive competition was higher on hay than silage, suggesting a preference for hay. Although the actual feed intake of hay was not reduced by restricting the feeding space as opposed to silage, the dramatic reduction in % of total observations spent feeding for some individuals suggests that more than one goat per feeding place can not be recommended. [Copyright &y& Elsevier]

This study investigated feeding competition within and between different age–sex classes of feral goats ( Capra hircus) on the Isle of Rum (northwest Scotland) from August to November 2000 (inclusive). Although contests in a feeding context were common, most were relatively passive: little overt agonistic behaviour was observed between opponents and the distance between feeding animals involved did not change significantly after an interaction. Month (but not sex or habitat type) had a significant effect on feeding interaction rates, and the proportion of interactions involving more intense forms of conflict was highest in November when forage availability was beginning to decline. The results show that the initiator won most feeding encounters, with adult males being dominant over females. The ability to win conflicts increased with age for both males and females. However, it decreased sharply for adult males older than 5 years, which may, in part, explain the reduced overwinter survival of these individuals. [ABSTRACT FROM AUTHOR]

Sexual segregation occurs widely in ungulates, and four principal hypotheses (predation, forage quality, social preferences and activity patterning) have been suggested as possible explanations. However, no single explanation has so far received widespread support. We used data on the grouping behaviour of feral goats, Capra hircus, on the Isle of Rum, Scotland, U.K. to test between competing hypotheses. We first used Conradt''s (1999, Animal Behaviour, 57, 1151–1157) test to show that sexual segregation is not a consequence of sex differences in habitat preference. Since the predation risk hypothesis can be ruled out by both the absence of important predators on Rum and the tendency for those individuals most sensitive to predation (mother–offspring pairs) to be the furthest away from their neighbours, any explanation for sexual segregation must either lie in differences in activity patterning or be the consequence of a social preference for associating with same-sex individuals. We analysed data on the patterns of fission, behavioural synchrony and neighbourhood in relation to party size and composition to show that the activity budget hypothesis is the more likely. However, the data also suggest that the social preferences hypothesis none the less has a residual influence on segregation tendencies of the Rum goats. We conclude that one likely reason for the conflicting results in the literature may be that all four hypotheses in fact apply simultaneously, but that their relative weightings may depend on habitat- and species-specific characteristics. [Copyright &y& Elsevier]

Introduced mammals are major drivers of extinction. Feral goats (Capra hircus ) are particularly devastating to island ecosystems, causing direct and indirect impacts through overgrazing, which often results in ecosystem degradation and biodiversity loss. Removing goat populations from islands is a powerful conservation tool to prevent extinctions and restore ecosystems. Goats have been eradicated successfully from 120 islands worldwide. With newly developed technology and techniques, island size is perhaps no longer a limiting factor in the successful removal of introduced goat populations. Furthermore, the use of global positioning systems, geographic information systems, aerial hunting by helicopter, specialized hunting dogs, and Judas goats has dramatically increased efficiency and significantly reduced the duration of eradication campaigns. Intensive monitoring programs are also critical for successful eradications. Because of the presence of humans with domestic goat populations on large islands, future island conservation actions will require eradication programs that involve local island inhabitants in a collaborative approach with biologists, sociologists, and educators. Given the clear biodiversity benefits, introduced goat populations should be routinely removed from islands. [ABSTRACT FROM AUTHOR]

Discusses Hawaii and the Galápagos Islands, which are two island ecosystems that are thought to be a significant and unique part of earth's biota. Characteristics of the two archipelagos, which are both of volcanic origin and are roughly similar in size; Observation that while Hawaii has only a single native terrestrial mammal, a bat, the Galápagos Islands have native rodents and reptiles; Damage which has been done to the vegetation of both archipelagoes from the grazing of feral goats; The impact of non-native black rats on the tortoise and dark-rumped petrel populations of the Galápagos; The problem of avian disease in Hawaii and the Galápagos; Outlook for the future management of island species invasions.

The article discusses the population recovery of endangered giant tortoises on the Galapágos island of Española. Topics discussed include the damage to the plants landscape of the island caused by feral goats, the work of biology professor James P. Gibbs who studied the conservation efforts on the island, and the hindrance to the growth of cactus, which is eaten by tortoises.

It has recently been claimed by Masseti that a wild goat survived on Montecristo Island until the first half of the 20th century and that subsequent selection procedures produced a goat that did not resemble any true wild goat. In the present note, it is emphasized that the Montecristo goat was in fact never taxonomically described. The fact that a Montecristo 'wild' goat has been included in the national and European legislation as a protected 'species' could only been explained with the decline of mammal taxonomy that has been observed in Western Europe during the second half of 20th century. [ABSTRACT FROM AUTHOR]

The article reports on the findings of a study on the risk of transmission of anaplasma phagocytophilum in feral goats in Northern Ireland. It cites the risk of transmission posed by feral ungulates as reservoirs of vectorborne pathogens to wild and domestic species as well as human beings. It notes the implications of the presence of A phagocytophilum in feral goat populations that inhabited forestry plantations used for recreation and for pasture.

The article reports on the Global Environment Facility (GEF) effort developed by the station and Galápagos National Park to eradicate invasive species in Galápagos Islands. According to a survey, some 140,000 feral goats were wiped off Isabela, Santiago and Pinta Islands through the GEF project. Another initiative of GEF is the elimination of fecal rats and cats since it have disturbed sites of mangrove finches and decimated subspecies of marine iguana. To add in the list, GEF is supporting a molecular pathology laboratory to develop measures against a possible West Nile virus invasion.