Influence of landscape structure on invasive predators: feral cats and red foxes in the brigalow landscapes, Queensland, Australia

2012 ◽  
Vol 39 (8) ◽  
pp. 661 ◽  
Author(s):  
Cameron A. Graham ◽  
Martine Maron ◽  
Clive A. McAlpine

Context Invasive mammalian predators are often associated with fragmented landscapes, and can compound the impacts of habitat loss and fragmentation on native fauna. Knowledge of how invasive predators are influenced by different landscape structures can assist in the mitigation of their impacts. Aims The aim of the present study was to investigate the influence of landscape structure and site-scale habitat attributes on the frequency of feral-cat and red-fox detections in fragmented agricultural landscapes. Methods Field surveys of the frequency of red-fox and feral-cat visitation at a site scale were stratified for six different habitat types in six study subregions. The habitat types were large remnant patch interior, large remnant patch edge, small remnant patch, roadside verge, regrowth patch and open agricultural land adjacent to a remnant patch. Sites were centred in a 1-km buffer area from which landscape composition and configuration were calculated. We applied a generalised linear model and an information-theoretic approach to determine the effect size and importance and rank of the explanatory variables on red-fox, feral-cat and pooled cat and fox detection rates. Key results The most important factors influencing detection rates had a positive effect and included: the dominance of cropping in the landscape (cat, fox, pooled cat and fox); and the density of vegetation at a site scale (fox, pooled cat and fox). The number of native habitat patches was also an important factor in the models of red foxes and pooled invasive predators. Conclusion Spatially heterogeneous cropping landscapes incur higher rates of invasive-predator detections than do intact native-woodland and pasture landscapes at the 1-km scale. At a site scale, elevated invasive-predator detections occurred at sites with dense vegetation, characteristic of narrow woodland and the edges of large woodland patches. Implications The research findings highlight that vertebrate pest management needs to target highly fragmented agricultural landscapes that are more likely to have elevated levels of invasive-predator activity. Landscape restoration efforts need to consider the redesign of landscapes to make them less suitable for predators and more hospitable for native wildlife.

Author(s):  
Ana Paula Dias Turetta ◽  
Rachel Bardy Prado ◽  
Gustavo de Souza Valladares

The landscapes are highly dependent on the dynamics of local land use and land cover, which directly affects landscape structure and determines the spatial patterns of forest patches, as well as to the major land uses within a specific region. The calculation of landscape metrics can support the understanding of such spatial distribution. In this study, 16 landscape metrics were analyzed in a drainage watershed in a high relief region in the Rio de Janeiro state, Southeastern Brazil, with the aim to evaluate the use of landscape metrics as indicators for agricultural management. Metrics calculation was followed by a Principal Component Analysis, which indicated the metrics that were most effective in evidencing the landscape structure in analysis. The results showed that the late-succession forest is the dominant component in the landscape. This class also presented the highest MPS metric value, related to the mean patch size by class. Some PCA results suggest that the metrics association was less effective in clustering the overgrown pasture, clean pasture, and annual crops classes, but this could result from the intrinsic association among those classes, by crop rotation, meaning the abandon of a site formerly occupied by an annual crop. Some metrics better suggested an interaction among land use classes and have potential to be use in the analyses of agricultural landscapes in high relief sites.


Oryx ◽  
2015 ◽  
Vol 50 (2) ◽  
pp. 239-243 ◽  
Author(s):  
Justine S. Alexander ◽  
Jeremy J. Cusack ◽  
Chen Pengju ◽  
Shi Kun ◽  
Philip Riordan

AbstractIn high-altitude settings of Central Asia the Endangered snow leopard Panthera uncia has been recognized as a potential umbrella species. As a first step in assessing the potential benefits of snow leopard conservation for other carnivores, we sought a better understanding of the presence of other carnivores in areas occupied by snow leopards in China's Qilianshan National Nature Reserve. We used camera-trap and sign surveys to examine whether other carnivores were using the same travel routes as snow leopards at two spatial scales. We also considered temporal interactions between species. Our results confirm that other carnivores, including the red fox Vulpes vulpes, grey wolf Canis lupus, Eurasian lynx Lynx lynx and dhole Cuon alpinus, occur along snow leopard travel routes, albeit with low detection rates. Even at the smaller scale of our camera trap survey all five carnivores (snow leopard, lynx, wolf, red fox and dhole) were observed. Kernel density estimates suggested a high degree of temporal overlap between the snow leopard and the fox, and the snow leopard and the lynx, as indicated by high overlap coefficient estimates. There is an opportunity to consider protective measures at the local scale that would benefit various species simultaneously. However, it should also be recognized that snow leopard conservation efforts could exacerbate human–wildlife conflicts through their protective effect on other carnivore species.


Parasitology ◽  
2002 ◽  
Vol 125 (2) ◽  
pp. 119-129 ◽  
Author(s):  
H. TSUKADA ◽  
K. HAMAZAKI ◽  
S. GANZORIG ◽  
T. IWAKI ◽  
K. KONNO ◽  
...  

The effect of bait-delivered anthelmintic to reduce the prevalence of Echinococcus multilocularis in wild red foxes was evaluated in Koshimizu, in the eastern part of Hokkaido, Japan. The study area (200 km2) was divided into baited and non-baited sections. The anthelmintic baits were distributed around fox den sites in the baited section every month for 13 months. After 1 year of the anthelmintic bait distribution, the prevalence of E. multilocularis in foxes, evaluated either by the parasite egg examination (from 27.1 to 5.6%) or coproantigen ELISA (from 59.6 to 29.7%), decreased in the baited section contrasting to that in the non-baited section (parasite egg: from 18.8 to 24.2%; ELISA: from 41.9 to 45.8%). The prevalence of E. multilocularis in grey red-backed vole Clethrionomys rufocanus, caught around fox dens, born after bait distribution also decreased and was significantly lower than that in non-baited section. However, within the study periods, the coproantigen-positive rate in fox faeces sporadically increased, while egg-positive rate constantly decreased. Since coproantigen ELISA can detect pre-patent infection, this observation indicates that reinfection pressure in the baited section was still high even after the 13 months of anthelmintic bait distribution. Therefore, the bait distribution longer than our study period is required for the efficient control of E. multilocularis in wild red fox population.


2016 ◽  
Vol 96 (4) ◽  
pp. 589-597 ◽  
Author(s):  
Magdalena Zatoń-Dobrowolska ◽  
Magdalena Moska ◽  
Anna Mucha ◽  
Heliodor Wierzbicki ◽  
Piotr Przysiecki ◽  
...  

This paper demonstrates the influence of artificial selection on morphometric traits in the red fox [Vulpes vulpes (Linnaeus, 1758)]. Measurements and two proportion coefficients were analysed in 132 wild and 199 farm red foxes. The two groups differed significantly (P ≤ 0.05) on all but one of the measurements. Eight out of 11 measurements were significantly greater in the farm fox population, while only tail length, ear height, and length of the right hind limb were greater in the population of wild foxes. The opposite trend was observed when analysing variation in the measurements — the farm foxes were characterized by a greater variability only in the case of body weight, body length, and breadth of chest. When analysing the sexual dimorphism index in different sex and population groups, in almost all analysed traits, the greatest differences occurred between farm males and wild females. All of the traits examined in this study are important for survival of wild foxes. However, because importance of some traits was reduced during domestication and selective breeding (farm foxes do not have to fight for survival), the genetic relationship between them may have weakened. Other possible causes of morphological differences between the studied groups of red foxes are discussed as well.


2021 ◽  
Vol 13 (10) ◽  
pp. 5424
Author(s):  
Martina Venturi ◽  
Francesco Piras ◽  
Federica Corrieri ◽  
Beatrice Fiore ◽  
Antonio Santoro ◽  
...  

The landscape is considered a strategic asset by the Tuscan regional government, also for its economic role, meaning that a specific Landscape Plan has been developed, dividing the region into 20 Landscape Units and representing the main planning instrument at the regional level. Following the aims of the Landscape Plan and the guidelines of the European Landscape Convention, it is necessary to develop an adequate assessment of the landscape, evaluating the main typologies and their characteristics. The aim of this research is to carry out an assessment of the landscape diversity in Tuscany based on 20 study areas, analyzing land uses and landscape mosaic structures through the application of landscape metrics: number of land uses, mean patch size (MPS), Hill’s diversity number, edge density (ED), patch density (PD), land use diversity (LUD). The results highlight a correlation between the landscape typologies (forest, agricultural, mixed, periurban) and the complexity of the landscape structure, especially in relation to MPS and PD, while the combination of PD and LUD calculated on the basis of a hexagonal grid allows obtaining landscape complexity maps. Despite the phenomena of reforestation and urban sprawl of recent decades, Tuscany still preserves different landscape typologies characterized by a good level of complexity. This is particularly evident in mixed landscapes, while agricultural landscapes have a larger variability because of different historical land organization forms. The methodology applied in this study provided a large amount of data about land uses and the landscape mosaic structure and complexity and proved to be effective in assessing the landscape structure and in creating a database that can represent a baseline for future monitoring.


Author(s):  
Emma Bloomfield

Invasive predators are a large and growing threat to species diversity and human well-being. One of the reasons invasive predators have a negative impact is that native prey species do not possess appropriate anti-predator defenses. However, rapid evolution may allow prey species to respond adaptively to introduced predators. When this occurs the impacts of invasive predators are mitigated. An invasive predator that is of concern in North America is the spiny water flea, Bythotrephes longimanus. It disrupts freshwater ecosystems through voracious consumption of zooplankton. Declines in zooplankton abundance and richness reduce water quality and recreational fishing opportunities. However, a species of zooplankton, Daphnia mendotae has been found to adaptively respond to B. longimanus. This adaptation is diel vertical migration, the behavioral change of occupying a lower position in the water column during the day to reduce predation risk. Despite the ecological and economic implications of this behavior in response to B. longimanus, it has only been studied in a few lakes. This study investigated adaptive diel vertical migration in D. mendotae from multiple lakes. This was done by measuring the vertical position of D. mendotae in artificial water columns. It was hypothesized that D. mendotae from lakes that have been invaded by B. longimanus will exhibit diel vertical migration in the presence of B. longimanus. If this hypothesis is supported, rapid evolution of diel vertical migration can be established as a widespread response. This would strengthen understanding of rapid evolution and allow lakes more vulnerable to B.longimanus to be identified.


2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Margarita Gil-Fernández ◽  
Robert Harcourt ◽  
Thomas Newsome ◽  
Alison Towerton ◽  
Alexandra Carthey

Abstract With urban encroachment on wild landscapes accelerating globally, there is an urgent need to understand how wildlife is adapting to anthropogenic change. We compared the behaviour of the invasive red fox (Vulpes vulpes) at eight urban and eight peri-urban areas of Sydney, Australia. We observed fox behaviour around a lure and compared fox activity patterns to those of potential prey and to two domestic predators (dogs—Canis lupus familiaris and cats—Felis catus). We assessed the influence of site type, vegetation cover, and distance from habitation on fox behaviour, and compared the temporal activity patterns of urban and peri-urban red foxes. Urban red foxes were marginally more nocturnal than those in peri-urban areas (88% activity overlap). There was greater overlap of red fox activity patterns with introduced mammalian prey in urban areas compared with peri-urban areas (90% urban vs 84% peri-urban). Red fox temporal activity overlapped 78% with cats, but only 20% with dogs, across both site types. The high degree of overlap with cats and introduced mammalian prey is most likely explained by the nocturnal behaviour of these species, while pet dogs are generally kept in yards or indoors at night. The behavioural differences we documented by urban red foxes suggest they may adapt to human modifications and presence, by being more nocturnal and/or more confident in urban areas.


2014 ◽  
Vol 59 (No. 6) ◽  
pp. 299-306 ◽  
Author(s):  
D. Zienius ◽  
G. Pridotkas ◽  
I. Jaceviciene ◽  
M. Ruzauskas

The objective of the present study was to assess the efficacy of an oral rabies vaccination (ORV) program in the period from 2006 to 2013 based on epidemiological data (Incidence of confirmed rabies in red foxes), biological marker evaluation (presence of tetracycline [TTC] indicating bait uptake), and the assessment of seroconversion (based on ELISA for rabies antibodies) in red foxes in Lithuania. Results were compared between juvenile and adult red foxes, and between the spring (March to May) and autumn (October to December) campaigns. On average, 20 baits/km<sup>2 </sup>were distributed over the entire territory of Lithuania. During the entire period of 2006&ndash;2013 1179 red foxes (10% of 11 829) were rabies-positive. While in 2006, 23.8% of tested foxes were rabies-positive, the incidence decreased to 2.4% in 2009, and 0.7% in 2011. Based on jaw bone investigation 78.1% of the foxes had ingested TTC from baits, 52.2% had seroconverted. The percentage of ELISA-positive red fox sera samples remained stable at 44.7&ndash;53.2% during both most recent ORV periods. The majority were adults (83%), 81.1 &plusmn; 8.54% of which were TCC-positive, and 73.8 &plusmn; 6.33% were TTC-positive juveniles. 52.5 &plusmn; 5.81% of adult red foxes had seroconversed, while 48.2 &plusmn; 4.51% of the young animals had a positive ELISA test in the years 2006 to 2013. This is in contrast to 2006 where only 29.5% of the young foxes were ELISA-positive. There were no significant differences between TTC- and ELISA-positive populations in different geographical regions of Lithuania. &nbsp;


2019 ◽  
Vol 9 (24) ◽  
pp. 5289
Author(s):  
Mari Hagenlund ◽  
Arne Linløkken ◽  
Kjartan Østbye ◽  
Zea Walton ◽  
Morten Odden ◽  
...  

Knowledge about the dispersal and gene flow patterns in wild animals are important for our understanding of population ecology and the connectedness of populations. It is also important for management relating to disease control and the transmission of new and emerging diseases. Our study aimed to evaluate the genetic structuring among comparative samples of red foxes in a small part of Scandinavia and to estimate the gene flow and potential directionality in the movements of foxes using an optimized set of microsatellite markers. We compared genetic samples of red foxes (Vulpes vulpes) from two areas in Sweden and two areas in Norway, including red fox samples from areas where the occurrence of the cyclophyllic tapeworm Echinococcus multilocularis has been documented, and areas without known occurrence of the parasite. Our results show a high level of gene flow over considerable distances and substantiates migration from areas affected with E. multilocularis into Norway where the parasite is not yet detected. The results allow us to better understand the gene flow and directionality in the movement patterns of red foxes, which is important for wildlife management authorities regarding the spread of E. multilocularis.


2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Sarah J Campbell ◽  
Wilbur Ashley ◽  
Margarita Gil-Fernandez ◽  
Thomas M Newsome ◽  
Francesca Di Giallonardo ◽  
...  

Abstract The Red fox (Vulpes vulpes) has established large populations in Australia’s urban and rural areas since its introduction following European settlement. The cryptic and highly adaptable nature of foxes allows them to invade cities and live among humans whilst remaining largely unnoticed. Urban living and access to anthropogenic food resources also influence fox ecology. Urban foxes grow larger, live at higher densities, and are more social than their rural counterparts. These ecological changes in urban red foxes are likely to impact the pathogens that they harbour, and foxes could pose a disease risk to humans and other species that share these urban spaces. To investigate this possibility, we used a meta-transcriptomic approach to characterise the virome of urban and rural foxes across the Greater Sydney region in Australia. Urban and rural foxes differed significantly in virome composition, with rural foxes harbouring a greater abundance of viruses compared to their urban counterparts. We identified ten potentially novel vertebrate-associated viruses in both urban and rural foxes, some of which are related to viruses associated with disease in domestic species and humans. These included members of the Astroviridae, Picobirnaviridae, Hepeviridae, and Picornaviridae as well as rabbit haemorrhagic disease virus-2. This study sheds light on the viruses carried by urban and rural foxes and emphasises the need for greater genomic surveillance of foxes and other invasive species at the human–wildlife interface.


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