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The Azores holds the largest population of Cory's shearwater Calonectris borealis (Cory, 1881) (Aves, Procellariiformes) in the world. Apart from a few mammal-free islets, the bulk of the population breeds in coastal areas on the main human-inhabited islands, where several non-native predators have been introduced. Throughout the entire year of the 2019 breeding season, we used motion-triggered cameras and regularly visited three colonies of Cory's shearwater to identify nest predators and the factors affecting nest predation. A total of 292,624 photos were obtained, of which 97.7% were of Cory's shearwaters, 1.7% of non-target species (e.g. other birds, rabbits) and 0.52% of potential predators. Of the monitored nests, 25.7% were predated (n = 9), mainly by black rats (n = 8), but also by cats (n = 1). The relative abundance of black rats in the nests was the main factor explaining nest mortality. This variable was significantly and negatively related with the daily survival rate of Cory's shearwater nestlings. Identification of the main nest predators is crucial for the management and conservation of native bird populations, particularly on oceanic islands, which harbour an important number of threatened and endemic species. [ABSTRACT FROM AUTHOR]

Restoration initiatives of ecosystems transformed by human actions require optimisation of eradication measures of introduced species, particularly in fragile insular ecosystems. We studied aspects of the spatial ecology of introduced feral cats (Felis catus) on subantarctic Auckland Island of New Zealand to assist eradication efforts of pests from this remote, biologically rich island. Firstly, we estimated home range sizes and identified core areas of activity based on movement-rooted dynamic Brownian bridge models. Second, we used resource selection functions with generalised linear mixed models to identify seasonal patterns of space use associated to topographic, vegetation and other landscape predictors. Lastly, we quantified cats daily movement rates within home ranges. Average home range size was larger than on other offshore islands and mainland New Zealand, which might relate to lower cat densities and the abundance and predictability of food resources on the island. Cats mostly selected mosaic areas of forest, shrubs and tall tussocks near the coast, and in predominantly flat areas or nearby steep cliffs, which are all typical habitats of seabirds and terrestrial birds. Cats also selected alpine short tussocks during the cold season, likely related to the upsurge of mice (Mus musculus) due to tussock mast seeding and to transiting to steep cliffy areas. Male cats had home ranges that were larger, contained more core areas, and covered longer daily distances in the warm season than females, which might be associated with different breeding and reproductive behaviour. Eradication tools will need to target all habitats on Auckland Island with increased efforts in areas of identified higher use by cats. Understanding aspects of pest species’ spatial ecology on offshore islands worldwide can assist decision-makers in optimising eradication programs such as Predator Free 2050 in New Zealand. [ABSTRACT FROM AUTHOR]

The Azores Archipelago holds the second most important population of Roseate Terns in the North Atlantic. However, the size of the population has been decreasing. In this study, we used remote-sensing cameras and visits to the main colonies of Common Terns Sterna hirundo and Roseate Terns S. dougallii on Terceira Island to identify the causes of breeding failure. Nest depredation by introduced mammals, particularly rats and cats, was the main cause of breeding failure, leading, in some cases, to the complete destruction of the colony. Additional threats included nest disturbance by humans and dogs, which caused the destruction of some nests. Measures aimed at mitigating depredation were tested but in the case of rodents, control plans proved difficult to achieve. This is probably because rodents are widespread in the Azores, they are not limited by food resources, and/or trapping methods are ineffective. [ABSTRACT FROM AUTHOR]

The Asian water buffalo was introduced in Brazil in in the late nineteenth century. Today the country harbours one of the largest populations in the world, most of it in the Amazon basin. The majority of populations are domesticated, but feral populations have established in several protected areas. One of the largest, comprising both feral and free-living domestic individuals, is in Lago Piratuba Biological Reserve (LPBR) and Maracá-Jipioca Ecological Station (MJES) in Amapá state. Water buffalo cause serious damage to floodplains in both areas and their population control has been recommended. In 2017, we conducted aerial surveys using the double-count technique to estimate the size and distribution of the water buffalo population at LPBR and MJES. To assess population trends, we compared our results with two previous population estimates (2007 and 2013) for the same areas as well as with data from the Brazilian agricultural census (2007 to 2017) for the region. We estimated a population of 17,782 and 686 buffalo at LPBR and MJES, respectively. Compared to previous surveys, the population at MJES has remained stable, but the LPBR population declined by more than 40% compared to the last survey. The decline was virtually limited to one survey sector at LPBR. The decline is mirrored by the agricultural census data, but its reasons are unclear. We recommend continued monitoring, as the population can quickly rebound to previous numbers if left unchecked. [ABSTRACT FROM AUTHOR]

Studies on feral cat diet offer important ecological information and are the first step towards determining their impact upon endangered species. However, in comparing seasonal changes in diet with seasonal prey availability, the scarce amount of research into oceanic islands worldwide must be considered when deciding if a specific population is actually affected by cat predation. Cat diet was analysed on Santa Luzia (Cabo Verde Islands) since this invasive predator is considered one of the main threats to native endangered species that require conservation measures. These previous studies were carried out in different seasons, providing contrasting results, skinks being more preyed upon in the rainy season and mice in the driest periods. To check these different results, we focussed on how cat diet varied seasonally in response to changes in prey abundance. Saurians were the most important prey group, followed by mice, invertebrates and birds. No seasonal differences were, however, observed in the different prey groups consumed, saurians being the main prey in both seasons. All cases reflected their respective abundances. Results corroborate the generalist and opportunistic trophic ecology of feral cats, providing important information to assess their impact on prey populations and design future eradication programmes. [ABSTRACT FROM AUTHOR]

Biological invasions are a major concern for biodiversity conservation. The release and escape of pet animals are the main sources of mammal invasions. Identifying potential invaders before they are introduced is a key tool for preventing the spread and impact of invasive alien species. Among the tools available for screening potential invaders are risk analysis protocols, which can also be used to assess the risk of species introduced in the past and limit or ban their import or commerce. We aimed to identify potential invasive mammals in the pet trade by applying a risk analysis protocol adapted to Brazil. Six alien mammals sold as pets in Brazil resulted high invasion risk. Rodents resulted the highest risk values. In order to prevent the release of invasive species through the pet trade it is necessary to avoid new introductions based on risk analysis, to identify species pathways, and to combat animal trafficking.

Wildlife management and conservation biology are full of conflict, especially in regard to introduced vertebrates in Hawai`i. At present, there are 17 introduced mammals with established wild populations in Hawai`i, including 6 ruminants, 4 rodents, 3 feral pets, pigs, donkeys, rock wallabies, and mongooses. Disagreement about the reliability of information on the impacts of introduced mammals in Hawai`i is one reason for conflict between stakeholders, which may undermine conservation and management programs. The objective of this research was to assess what science has recorded in regards to the impact of introduced mammals on the native flora, fauna, and ecosystems of the Hawaiian Islands. A literature (peer-reviewed articles, theses, dissertations, and grey literature) search for data on the impact of these species resulted in 156 articles, which were assigned to 1 of 6 categories that describe science’s ‘Level of understanding’ of the impacts of mammals in Hawai`i. The vast majority of the available data (134/156 articles) resulted from basic observations or general exclosure plots. In terms of their impact in Hawai`i, cats (21 articles), black rats (27 articles), and pigs (40 articles) are the most researched and hence best understood species. Very little is known about the impacts of dogs, rabbits, brush-tailed rock wallabies, and donkeys on the flora, fauna, and ecosystems of Hawai`i. Analysis of the dates of publication of articles suggests research may be influenced by the level of controversy surrounding a species.

We visited San Ambrosio Island off northern Chile (26°21'S, 079°47'W) on 10-12 December 2019. We found a large population of Kermadec Petrel Pterodroma neglecta juana that appeared to be healthy. In the area that we could survey, we estimated at least 22 686 breeding pairs, which is an underestimate of the entire population as we could not access some steep areas. Introduced mammals, which have since been eradicated, caused a loss of island vegetation that might be a drawback for this population, as shading from the sun appears to be important for nest-site selection. Egg-laying started by early December. We assessed 223 birds with respect to coloration: most birds were intermediate phase (65%) and the rest were either very dark (23%) or very pale (12%). We found skeletal remains of goats and rabbits on the island but no living mammals, although a single goat may still be alive. In the context of an estimated world population of ~100 000 pairs of Kermadec Petrel, the San Ambrosio Island population contributes significantly. [ABSTRACT FROM AUTHOR]

The wild boar (Sus scrofa) is a problematic invasive species which has colonized the threatened Brazilian Atlantic Forest. Our objective was to evaluate if population control and seasonality affect the circadian rhythm of wild boar activity. Wild boar activity was monitored by camera-traps for 1 year without population-control methods and 1 year with population-control methods implemented in the area. Before population control was implemented, wild boar activity was uniform across 24 h, with animals being active at any given time (cathemeral). After the population control, wild boars concentrated their activities on the daylight period. Also, wild boars were more active during the wet season, possibly influenced by the presence of seeds of Araucaria angustifolia trees. Based on these results, control measures should be conducted during the wet season and different management strategies, such as the use of rifles with telescopic sights and silencers, should be tested. [ABSTRACT FROM AUTHOR]

Grey-faced Petrels (Pterodroma gouldi) are burrow-nesting seabirds endemic to New Zealand. They usually breed on mammal-free offshore islands along the North Island coast. Mechanisms by which breeding colonies can persist on the North Island with introduced mammals present are still uncertain. Motion-sensing video cameras were used in the Waitakere Ranges to determine the types of interaction between resident introduced mammal species and petrel breeding burrows. Existing predator control is reducing the total count of recorded interactions by predators, with rabbits (Oryctolagus cuniculus) entering burrows dominating interactions. The interaction of ship rats (Rattus rattus) or rabbits with breeding burrows had no influence on egg-laying or chick-hatching success. Grey-faced Petrels remained in breeding burrows, despite high interaction frequencies of introduced mammals prior to the egg-laying stage. Whilst our data show no impact of mammalian visit rates on Grey-faced Petrel breeding success, other published studies suggest that population recovery might be enhanced by site-specific trapping and baiting methods which also target rabbits. [ABSTRACT FROM AUTHOR]

The introduction of mammals on oceanic islands currently threatens or has caused the extinction of many endemic species. Cats and rats represent the major threat for 40 % of currently endangered island bird species. Direct (predation) and/or indirect (exploitative competition for food resource) trophic interactions are key mechanisms by which invaders cause the decrease or extinction of native populations. Here, we investigated both direct and indirect trophic interactions amongst four predator species (i.e. animals that hunt, kill and feed on other animals), including three introduced mammals (Felis silvestris catus, Rattus rattus and Rattus exulans) and one critically endangered native bird, the Niau kingfisher (Todiramphus gertrudae). All four species’ diets and prey availability were assessed from sampling at the six main kingfisher habitats on Niau Island during the breeding season. Diet analyses were conducted on 578 cat scats, 295 rat digestive tracts (218 R. exulans and 77 R. rattus) and 186 kingfisher pellets. Despite simultaneous use of morphological and PCR-based methods, no bird remains in cat and rat diet samples could be assigned to the Niau kingfisher, weakening the hypothesis of current intense predation pressure. However, we determined that Niau kingfishers mainly feed on introduced and/or cryptogenic prey and highlighted the potential for exploitative competition between this bird and both introduced rat species (for Dictyoptera, Coleoptera and Scincidae). We recommend removing the cats and both rat species, at least within kingfisher breeding and foraging areas (e.g. mechanical or chemical control, cat sterilisation, biosecurity reinforcement), to simultaneously decrease predation risk, increase key prey availability and boost kingfisher population dynamics. [ABSTRACT FROM AUTHOR]

Abstract The diversity of Australia's mammalian fauna has decreased markedly since European colonisation. Species in the small-to-medium body size range have been particularly badly affected. Feral cats and foxes have played a central role in this decline and consequently strategies for reducing their numbers are being evaluated. One such strategy is the reintroduction to the mainland of the Tasmanian devil, Sarcophilus harrisii. Here, we provide a palaeontological perspective on this proposal. We begin by collating published records of devil remains in Quaternary deposits. These data show that the range of devils once spanned all the main ecological zones in Australia. This indicates that they are capable of coping with a wide range of climatic and environmental conditions, and suggests that they could conceivably be reintroduced much more widely than has been thought possible hitherto. Subsequently, we examine fossils and coprolites from two sites in the Willandra Lakes Region World Heritage Area. These specimens not only support the suggestion that devils have wide ecological tolerances, but also suggest that devils can coexist with native small-to-medium species over long periods of time, which addresses one of the major concerns about the proposed reintroduction. We believe these two sets of palaeontological observations add substantial weight to the idea of reintroducing devils to the mainland as a way of suppressing cat and fox numbers. [ABSTRACT FROM AUTHOR]

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Invasive mammals are implicated in the decline or extinction of numerous insular vertebrate species worldwide, yet rediscoveries of supposedly extinct vertebrates occur regularly. In particular, recent records of secretive amphibian and reptile taxa in the Fiji Islands show that earlier claimed extirpations of Fijian wildlife were erroneous. We add to this growing body of evidence by documenting the Fiji barred treeskink Emoia trossula (Squamata: Scincidae) from Vanua Levu island, Fiji, where it was widely considered extirpated. Regional literature, coupled with this new record, emphasizes the conservation importance of remote forest blocks in Fiji as refugia against nonnative predatory mammals. Moreover, a clear need exists for additional survey work in Fiji to document the contemporary distribution of endemic and endangered herpetofaunal species across the archipelago. [ABSTRACT FROM AUTHOR]

Invasive species management requires practical evidence of the impacts of introduced species over ecosystem structure and functioning. Theoretical ecology and empirical data support the potential of introduced mammals to drive native species to extinction, indeed the majority of practical evidence comes from insular environments, where conditions may differ from the mainland. We analyzed the effects of an introduced lagomorph, the eastern cottontail Sylvilagus floridanus on two native mammals, the European hare Lepus europaeus and the red fox Vulpes vulpes. We used relative abundances collected over 8 years at 30 protected areas in Italy. A generalized linear mixed model was fit to test various hypotheses about the relationships between cottontails, foxes and climatic conditions over the abundance of native hares. In our model, hare and cottontail abundances did not show a negative relationship and we believe that no direct competition occurs between the two species. However, the relationship between fox and hare abundances, positive when cottontails were scarce, became more and more negative as cottontails increased: this supports the hypothesis that indirect dynamics like apparent competition exists between the two lagomorphs. Climatic conditions, expressed through the North Atlantic Oscillation, did not affect the relationship between cottontail and hare abundances. As the impact of parasites on mammal populations is generally climate dependent, we believe that cottontails do not play a direct role in the cycle of parasites affecting hares. Our results provide a clue that an invasive mammal, the eastern cottontail, is modifying the predator-prey relationship between two native species in a non-insular environment. The existence of such dynamics should lead wildlife managers to account for the effect of introduced species in their decision making, directing control activities on cottontails and not on native foxes. [ABSTRACT FROM AUTHOR]

Invasive mammals are an ongoing threat at many seabird breeding locations, while impacts from climate change can occur over broad time scales. Combining management strategies for invasive mammal and climate change impacts is important for mitigating current threats and maximizing seabird survival into the future. We assessed all 713 islands with threatened seabirds for conservation importance, immediate benefits of three invasive mammal management actions, and risk of climate-change related flooding. Preventing invasions on the 397 islands without invasive mammals could benefit 72 seabird species. Invasive mammal eradication or localized action on 249 and 67 islands could benefit 71 and 46 seabird species, respectively. The long-term risk of flooding on the 713 islands was low (69%). Low-risk islands were concentrated where eradications or localized action were highlighted (75% and 100% of islands, respectively). These results inform management feasibility assessments and highlight rare opportunities to make significant contributions to seabird conservation. [ABSTRACT FROM AUTHOR]

Land mammals of the Caribbean Islands biodiversity hotspot have suffered a high rate of extinction since human arrival, principally in the last 500 years since colonialism began. Here, we present an extensive review and bibliography of this topic in Cuba, including details regarding the surviving endemic species of volant and terrestrial mammals and locations of species on 121 protected areas. We analyzed patterns of species richness, endemism, body mass, diet, habitat, geographic distribution of the observed richness, conservation threats, and possible causes and threats to future extinction. Cuban mammal biodiversity is comprised of 59 native species, 24 extinct species and 35 extant species, most of which are endemic to the Cuban archipelago. We compared the threats of habitat destruction and hunting, with emphasis on invasive mammal species as drivers of historical extinction in Cuba. A total of 44 mammal species have been introduced since 1509, with 33 invasive species living in the wild and exerting differing degrees of impact, principally by predation and competition. Additionally, we evaluated interactions among invasive and native mammals, emphasizing predation of feral cats upon Solenodon cubanus, Capromys pilorides, and other small endemic vertebrates as determined from analyses of scat contents. We found that black rats (Rattus rattus) reach densities of 147-322 individuals/ha in Solenodon habitat, thus likely are major competitors for food and refuges to these evolutionarily distinct and endangered Cuban mammals. [ABSTRACT FROM AUTHOR]

Indicator taxa are increasingly being used to evaluate the natural environment because they provide both quantified and simplified information about complex phenomena and because they result in huge cost savings compared with monitoring entire biotas. In this paper, we examine the suitability of an iconic New Zealand invertebrate, the tree wētā (Orthoptera: Anostostomatidae: Hemideina species), as a bioindicator for invertebrates under a national biodiversity monitoring scheme in New Zealand. Tree wētā are common and widespread in New Zealand, comprising a distinctive component of the native invertebrate fauna, being large-bodied (up to 40 mm in length), relatively long-lived, flightless, and nocturnal. Arboreal tree wētā species are commonly monitored in conservation areas containing scrub or forest, particularly after mammal control, because they can be easily monitored using artificial roosts without harming them and they are readily identified by field workers. We evaluated whether data supported the use of tree wētā as a range of bioindicators for such monitoring and conclude that the arboreal species are good indicators for monitoring the effects of controlling the abundance of insectivorous mammals and that they are likely to be reliable population indicators of taxa sensitive to mammalian predation pressure, especially by rodents. However, it is unlikely that arboreal tree wētā are useful population indicators of habitat change (e.g. degradation and fragmentation) as they commonly survive in exotic vegetation and urban gardens throughout New Zealand. Although poorly studied for indicator value, tree wētā may not be good biodiversity indicators although there are insufficient data to establish this. We recommend further research be undertaken to develop standardised methods for monitoring so that conservation managers and researchers produce results that are consistent and comparable across different locations. [ABSTRACT FROM AUTHOR]

The invasion of alien species is an important cause of biodiversity loss worldwide, and many mammals are considered successful invaders outside their former range, with recognized detrimental effects to native ecosystems. Our aim was to review the current literature on alien mammals that have established feral populations in Brazil and to systematize the existing knowledge. Furthermore, we evaluated the current distributions of all invasion mammals and discuss different management actions, including eradication techniques for island populations. We found 17 species of alien mammals living in the wild in Brazil. Based on the current literature and databases regarding invasive species, Lepus europaeus and Sus scrofa had the largest distributions in the Brazilian territory and seem to continue expanding their geographic distributions. Feral dogs and cats were the main alien predators threatening wildlife conservation, especially in protected areas. Further, we call attention to the invasion of Bubalus bubalis, a large species that currently thrives in isolated populations but seems to be quickly expanding its distribution. In conclusion, alien mammals are widespread in Southern and Southeastern Brazil, but at least four ungulate species (Indian sambar, horse, goat, and axis deer) still have small and isolated populations. Finally, future efforts need to evaluate the impacts of alien mammals in Brazil and techniques for their control. [ABSTRACT FROM AUTHOR]

In 2016, the New Zealand Government announced a policy to rid the country of key introduced predators (possums (Trichosurus vulpecula), ship rats (Rattus rattus), Norway rats (R. norvegicus) and mustelids (Mustela spp.)) by 2050. An interim goal under this policy is to remove all mammalian predators (the key species as well as mice (Mus musculus), kiore (R. exulans), cats (Felis catus), pigs (Sus scrofa) and hedgehogs (Erinaceus europaeus)) from island nature reserves by 2025. We identify the New Zealand islands over one hectare managed as reserves by the Department of Conservation (DOC) that have mammalian predators that can be eradicated. There are over 850 islands, islets, stacks and vegetated rocks in the New Zealand archipelago. We exclude islands in lakes and rivers and those smaller than one hectare, which leaves 616 islands, less than half of which are under some form of reserve status (286 islands entirely managed by DOC and 13 under mixed tenures but with some reserve land). One or more mammalian predators are known to occur on 48 of these islands, with the Government's 2050 target species on 42 islands and other predators (in the absence of the target species) on six islands. The Government's 2025 goal nominates one class of reserve, nature reserves. Of the 48 islands, just four islands are classed as nature reserves -- two (Mauitaha and Araara Islands) with protected kiore in the Hen and Chickens group and two in the Auckland Islands group (Auckland with mice, cats and pigs; and Masked with mice and cats) -- i.e. none with the key species of the wider 2050 goal. Therefore, we consider other reserve classes but place more or less strict risks of reinvasion, as indexed by known swimming ranges of the predators, to judge the feasibility of eradication. Relaxing the reserve class of the island, but not our selection of swimming ranges, results in 15 candidate islands where all mammalian predators present could be eradicated for the 2025 interim goal. Decisions on which islands to select for the programme need to consider costs and other constraints to eradicate different combinations of predators, and whether the island and its predators provide templates for the wider vision of a predator-free New Zealand, i.e. whether any of the key 2050 predators are present, the size of the island, and/or the presence of human inhabitants that complicate the predators to be targeted or constrain the use of some control methods. [ABSTRACT FROM AUTHOR]

Humans have an extremely long history of transporting and introducing mammal species outside their native geographic ranges. The characteristics of the species introduced (taxonomy, life-history, ecology, environment) can all influence which traits are available (and selected) for establishment, and subsequent invasive spread. Understanding the non-randomness in species introductions is therefore key to understanding invasions by alien species. Here, we test for selectivity in the identities and traits of mammal species introduced worldwide. We compiled and analysed a comprehensive database of introduced mammal species, including information on a broad range of life history, ecological, distributional and environmental variables that we predicted to differ between introduced and non-introduced mammal species. Certain mammal taxa are much more likely to have been introduced than expected, such as Artiodactyls in the families Bovidae and Cervidae. Rodents and bats were much less likely to have been introduced than expected. Introduced mammal species have significantly larger body masses, longer lifespans and larger litter sizes than a random sample of all mammal species. They also have much larger native geographic ranges than expected, originate from significantly further north, from cooler areas, and from areas with higher human population densities, than mammal species with no recorded introductions. The traits and distributions of species help determine which have been introduced, and reflect how the evolutionary history of mammals has resulted in certain species with certain traits being located in the way of human histories of movement and demands for goods and services. The large amount of unexplained variation is likely to relate to the intrinsically stochastic nature of this human-driven process. [ABSTRACT FROM AUTHOR]

Predation of indigenous birds by ship rats (Rattus rattus, [Muridae]) is an international conservation crisis and has been implicated in the decline of many endemic species. Effective management of threatened ecosystems relies on accurate assessments of invasive species impacts on native wildlife. To quantify the link between ship rat abundance and survival of small, endemic birds we investigated the prevalence of rat predation on nesting New Zealand Fantails (Rhipidura fuliginosa placabilis, [Rhipiduridae]), and its importance relative to other risk factors such as nest microsite. We surveyed 106 nests across forested reserves in Wellington City, New Zealand. Local abundance of ship rats was indexed using chew-cards placed around the nest and with tracking tunnels throughout reserves. We modeled the effects of ship rat abundance, weather, observer impact, and attributes of the nest for their influence on nest survival. Fantails were more likely to abandon nests located higher in trees and those built earlier in the breeding season. More nests failed when rat abundance was higher. Where ship rat abundance reached a 25% chew-card index (CCI), the probability of the nest surviving dropped below 50%, and for CCI above 45% only 20% of nests were predicted to survive. However, Fantails also exhibited a resilient strategy that improved survival because nests located on thinner branches were less likely to suffer predation. Our research suggests that nesting strategies of Fantails involve trade-offs and strategies that might protect them against one threat, might expose them to others. Fantails are a common endemic species and cope with moderate levels of nest predation, however conservation of small endemic birds with less resilient breeding strategies is likely to require management of ship rat populations to low levels.

The three surviving 'brush-tailed' bettong species- Bettongia gaimardi (Tasmania), B. tropica (Queensland) and B. penicillata (Western Australia), are all classified as threatened or endangered. These macropodids are prolific diggers and are recognised as important 'ecosystem engineers' that improve soil quality and increase seed germination success. However, a combination of introduced predators, habitat loss and disease has seen populations become increasingly fragmented and census numbers decline. Robust phylogenies are vital to conservation management, but the extent of extirpation and fragmentation in brush-tailed bettongs is such that a phylogeny based upon modern samples alone may provide a misleading picture of former connectivity, genetic diversity and species boundaries. Using ancient DNA isolated from fossil bones and museum skins, we genotyped two mitochondrial DNA (mtDNA) genes: cytochrome b (266 bp) and control region (356 bp). These ancient DNA data were combined with a pre-existing modern DNA data set on the historically broadly distributed brush-tailed bettongs (~300 samples total), to investigate their phylogenetic relationships. Molecular dating estimates the most recent common ancestor of these bettongs occurred c. 2.5 Ma (million years ago), which suggests that increasing aridity likely shaped their modern-day distribution. Analyses of the concatenated mtDNA sequences of all brush-tailed bettongs generated five distinct and well-supported clades including: a highly divergent Nullarbor form (Clade I), B. tropica (Clade II), B. penicillata (Clades III and V), and B. gaimardi (Clade IV). The generated phylogeny does not reflect current taxonomy and the question remains outstanding of whether the brush-tailed bettongs consisted of several species, or a single widespread species. The use of nuclear DNA markers (single nucleotide polymorphisms and/or short tandem repeats) will be needed to better inform decisions about historical connectivity and the appropriateness of ongoing conservation measures such as translocations and captive breeding. [ABSTRACT FROM AUTHOR]

Pinus contorta is a widespread and ecologically damaging invasive tree in the southern hemisphere. Land managers want control methods that limit reinvasion by P. contorta and promote the recovery of native plant communities and ecosystem functions. Recovery of native vegetation may be slow if native seed supply is limited and/or introduced mammals destroy seeds and seedlings. We investigated how tree control method (felling or poisoning), seed addition, and exclusion of introduced mammals affected subsequent seedling establishment in montane stands of invasive P. contorta. Tree control method had a significant effect on seedling establishment: felling trees promoted establishment of P. contorta seedlings, whereas poisoning trees favoured establishment of native seedlings (provided seeds were available). Native seedling establishment was higher where seeds were sown, indicating native seed limitation at these sites. Excluding introduced mammals increased P. contorta seedling establishment, but did not have a significant effect on native seedling establishment. Our results indicate that poisoning P. contorta is a better management approach than felling where native seedling establishment is the desired outcome, and that this outcome can be enhanced by sowing native seed. [ABSTRACT FROM AUTHOR]

Successful pest-mammal eradications from remote islands have resulted in important biodiversity benefits. Near-shore islands can also serve as refuges for native biota but require ongoing effort to maintain low-pest or pest-free status. Three management options are available in the presence of reinvasion risk: (1) control-to-zero density, in which immigration may occur but reinvaders are removed; (2) sustained population suppression (to relatively low numbers); or (3) no action. Biodiversity benefits can result from options one and two. The management challenge is to make evidence-based decisions on the selection of an appropriate objective and to identify a financially feasible control strategy that has a high probability of success. This requires understanding the pest species population dynamics and how it will respond to a range of potential management strategies, each with an associated financial cost. We developed a two-stage modeling approach that consisted of (1) Bayesian inferential modeling to estimate parameters for a model of pest population dynamics and control, and (2) a forward projection model to simulate a range of plausible management scenarios and quantify the probability of obtaining zero density within four years. We applied the model to an ongoing, six-year trapping program to control stoats ( Mustela erminea) on Resolution Island, New Zealand. Zero density has not yet been achieved. Results demonstrate that management objectives were impeded by a combination of a highly fecund population, insufficient trap attractiveness, and a substantial proportion of the population that did not enter traps. Immigration is known to occur because the founding population arrived on the island by swimming from the mainland. However, immigration rate during this study was indistinguishable from zero. The forward projection modeling showed that control-to-zero density was feasible but required greater than a two-fold budget increase to intensify the trapping rate relative to population growth. The two-stage modeling provides the foundation for a management program in which broad-scale trials of additional trapping effort or improved trap lures would test model predictions and increase our understanding of system dynamics. [ABSTRACT FROM AUTHOR]

The raccoon dog Nyctereutes procyonoides is a newly established alien species in Europe that spread rapidly into many European countries. They were introduced into Latvia, Estonia, and Belarus. Lithuania has been colonized by immigrants from neighboring countries (Belarus and Latvia) and since 1960 the species has occupied the whole country. The data on genetic diversity of the raccoon dog are rather limited, and not all parts of the Baltic region have been covered by previous analyses. In order to compare the level of genetic diversity and describe phylogeographic patterns throughout the raccoon dog distribution in the Palearctic region, a mitochondrial DNA control region was used, and the current 22 sequences were combined with the sequences from earlier data (n = 32). The analysis of a 540-bp fragment of the mtDNA control region in raccoon dogs inhabiting Lithuania revealed 9 haplotypes with 19 variable positions. The phylogenetic relationships among the haplotypes demonstrated the presence of two haplogroups. The patterns of molecular genetic variation in raccoon dogs from Lithuania obtained in the present study indicated higher genetic diversity of these animals as compared with those from West Europe, but lower genetic polymorphism as compared with raccoon dogs introduced to the European part of Russia. [ABSTRACT FROM AUTHOR]

Invasive introduced mammals ( IIMs) have ecological and social dimensions that require holistic research to integrate academic disciplines with basic and applied sciences., We assessed current knowledge of IIMs to determine trends in their study and management in southern South America., A keyword search was used to select indexed papers in the Web of Science. These were reviewed to assess each study's objective, methodology, country, publication year, and taxa. Unpublished 'grey' literature was added to evaluate further each species' native range, year of introduction, the reason for its introduction, its distribution, dispersal pathways, impacts, and management., Most of the 190 peer-reviewed publications were focused on autecology and impacts of IIMs; less than 4% addressed management or social topics. Twenty-three IIMs have been documented in the study area. The southern Magellanic subpolar forest was the most invaded ecoregion (17 spp.), and the most studied orders, from 440 records in 190 papers, were Artiodactyla (35%) and Rodentia (28%). Together, livestock and commensals brought during early European colonisation constituted 44% of this assemblage, but hunting was the major reason behind the introduction of IIMs (30%)., To enhance policies and institutional frameworks pertaining to biological invasions, we highlight the importance of: 1) recognising the presence and spread of IIMs in 'pristine' or protected areas; 2) improving controls to prevent new introductions and escapes; 3) including social and cultural aspects of biological invasions in research and management plans; 4) reinforcing hunting regulations; 5) establishing long-term programmes to monitor distribution and dispersion; 6) creating mechanisms for scientists and managers to co-produce research and policy programmes oriented towards applied issues; 7) developing pilot management projects in critical areas; 8) achieving societal involvement in management programmes to ensure public acceptance; and 9) developing prioritisation tools, as resources needed to manage IIMs are often limited. [ABSTRACT FROM AUTHOR]

Food-based baits and lures remain the mainstay of eradication and monitoring methodologies for invasive mammalian species. To date, however, best-practise baits and lures for rats and possums have not been systematically compared to alternative food-based products in ways that quantify their effectiveness on free-ranging, wild animals. We designed a rapid bioassay using chew-cards to present large numbers of food-based products to free-ranging rats and possums to assess their attractiveness and consumption compared to current standards. We used linear mixed-effects regression analysis and an information-theoretic model set to consider the nutritive drivers of consumption for each species with the aim of informing the design of, and future search for, baits. Current standards were statistically outperformed in our trials. For rats, cheese, milk chocolate, Nutella and walnut were statistically more attractive than the peanut butter standard. For possums, apricot and almond were statistically more attractive that the cinnamon standard. Model comparisons indicate that energy, particularly from fats, is the most important determinant of consumption by rats, while protein is the most important determinant of consumption by possums. Our results demonstrate that current standard lures for both species could be more attractive whilst the inclusion of fat to rat baits and protein to possum baits could increase bait consumption and improve control operation outcomes. Further, our bioassay provides practitioners a cost effective and rapid methodology to systematically assess large numbers of food products on free-ranging, wild animals thus providing more realistic results than those obtained under pen or laboratory conditions. [ABSTRACT FROM AUTHOR]

Introduced herbivores frequently inflict significant, yet patchy damage on native ecosystems through selective browsing. However, there are few instances where the underlying cause of this patchy damage has been revealed. We aimed to determine if the nutritional quality of foliage could predict the browsing preferences of an invasive mammalian herbivore, the common brushtail possum (Trichosurus vulpecula), in a temperate forest in New Zealand. We quantified the spatial and temporal variation in four key aspects of the foliar chemistry (total nitrogen, available nitrogen, in vitro dry matter digestibility and tannin effect) of 275 trees representing five native tree species. Simultaneously, we assessed the severity of browsing damage caused by possums on those trees in order to relate selective browsing to foliar nutritional quality. We found significant spatial and temporal variation in nutritional quality among individuals of each tree species examined, as well as among tree species. There was a positive relationship between the available nitrogen concentration of foliage (a measure of in vitro digestible protein) and the severity of damage caused by browsing by possums. This study highlights the importance of nutritional quality, specifically, the foliar available nitrogen concentration of individual trees, in predicting the impact of an invasive mammal. Revealing the underlying cause of patchy browsing by an invasive mammal provides new insights for conservation of native forests and targeted control of invasive herbivores in forest ecosystems. [ABSTRACT FROM AUTHOR]

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Since 2004 there has been mounting evidence of the severe impact of introduced house mice (Mus musculus L.) killing chicks of burrow-nesting petrels at Gough Island. We monitored seven species of burrow-nesting petrels in 2014 using a combination of infra-red video cameras augmented by burrowscope nest inspections. All seven camera-monitored Atlantic petrel (Pterodroma incerta Schlegel) chicks were killed by mice within hours of hatching (average 7.2±4.0 hours) with an 87% chick failure rate (n=83 hatchlings). Several grey petrel (Procellaria cinerea Gmelin) chicks were found with mouse wounds and 60% of chicks failed (n=35 hatchlings). Video surveillance revealed one (of seven nests filmed) fatal attack on a great shearwater (Puffinus gravis O’Reilly) chick and two (of nine) on soft-plumaged petrel (Pterodroma mollis Gould) chicks. Mice killed the chicks of the recently discovered summer-breeding MacGillivray’s prion (Pachyptila macgillivrayi Mathews), with a chick mortality rate of 82% in 2013/14 and 100% in 2014/15. The closely-related broad-billed prion (P. vittata Forster) breeds in late winter and also had a chick mortality rate of 100% in 2014. The results provide further evidence of the dire situation for seabirds nesting on Gough Island and the urgent need for mouse eradication. [ABSTRACT FROM AUTHOR]