scholarly journals A triple threat: high population density, high foraging intensity and flexible habitat preferences explain high impact of feral cats on prey

2021 ◽  
Vol 288 (1942) ◽  
pp. 20201194
Author(s):  
Rowena P. Hamer ◽  
Riana Z. Gardiner ◽  
Kirstin M. Proft ◽  
Christopher N. Johnson ◽  
Menna E. Jones

Alien mammalian carnivores have contributed disproportionately to global loss of biodiversity. In Australia, predation by the feral cat and red fox is one of the most significant causes of the decline of native vertebrates. To discover why cats have greater impacts on prey than native predators, we compared the ecology of the feral cat to a marsupial counterpart, the spotted-tailed quoll. Individual prey are 20–200 times more likely to encounter feral cats, because of the combined effects of cats' higher population densities, greater intensity of home-range use and broader habitat preferences. These characteristics also mean that the costs to the prey of adopting anti-predator behaviours against feral cats are likely to be much higher than adopting such behaviours in response to spotted-tailed quolls, due to the reliability and ubiquity of feral cat cues. These results help explain the devastating impacts of cats on wildlife in Australia and other parts of the world.

2012 ◽  
Vol 39 (3) ◽  
pp. 258 ◽  
Author(s):  
Andrew J. Bengsen ◽  
John A. Butler ◽  
Pip Masters

Context Effective feral-cat (Felis silvestris catus) management requires a sound understanding of the ways cats use their environment. Key characteristics of landscape use by cats vary widely among different regions and different conditions. Aims The present study aimed to describe the most important characteristics of landscape use by feral cats on a large, human-populated island, and to use this information to guide the development of feral-cat management programs. Methods We used GPS tracking collars to record the movements of 13 feral cats at two sites on Kangaroo Island, South Australia, for between 20 and 106 days. We described home-range extents by using local convex hulls, and derived management suggestions from examination of home-range and movement data. Key results Median feral-cat home range was 5.11 km2, and this did not differ between sexes or sites. Cats at a fragmented pastoral site tended to favour woody vegetation over open paddocks, but habitat preferences were less clear at a bushland site. Cats that preferentially used treelines at the pastoral site were almost twice as likely to be recorded close to a tree-line junction as expected. Conclusions Control programs for feral cats on Kangaroo Island should deploy control devices at a density no less than 1.7 devices km–2. Spatial coverage should be as large as practicable or repeated frequently. Infrequent programs covering small areas can be expected only to provide short-term reductions in cat abundance. Implications The information gained from the present study will contribute to the development of strategic sustained management plans for feral cats on Kangaroo Island. The principles from which we inferred management guidelines are applicable to other regions and species.


2020 ◽  
Vol 7 (2) ◽  
pp. 419-436
Author(s):  
Olga Igorevna Severskaya

The article is devoted to the consideration of a poetic text as a communicative phenomenon with a high impact potential. The author defines the features of poetic communication, which is both mass and interpersonal, and its main goal, which is the poet’s desire to communicate author’s vision of the world and thereby change the picture of the reader’s world, achieving empathy from it. Based on the understanding of the speech strategy as a cognitive communication plan, a program for generating and perceiving speech, the author talks about the fundamental reversibility of text-generating and interpretative strategies and offers own classification of strategies and tactics that are most often used in modern poetry. In this classification, the main communicative strategies of self-presentation and rapprochement with the reader are associated with auxiliary discursive strategies of actualizing, dramatizing and dialogizing the text and programming interpretations by tactics for highlighting objects and situations using sound “gestures”, pointing to the referent, framing, directly introducing the reader into the communicative context, attracting the recipient’s attention through appeals and pragmatic instructions, interrogation, and some others. Particular attention is paid to the multimodality of interactions and its specific manifestations in poetic discourse. The study is based on the material of Russian poetry of the 1980- 2000s using the methods of intent and discourse analysis.


2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Ahmad N. Abou Tayoun ◽  
Heidi L. Rehm

AbstractWe highlight the current lack of representation of the Middle East from large genomic studies and emphasize the expected high impact of cataloging its variation. We discuss the limiting factors and possible solutions to generating and accessing research and clinical sequencing data from this part of the world.


2021 ◽  
Vol 261 ◽  
pp. 109284
Author(s):  
Alyson M. Stobo-Wilson ◽  
Brett P. Murphy ◽  
Heather M. Crawford ◽  
Stuart J. Dawson ◽  
Chris R. Dickman ◽  
...  
Keyword(s):  
Red Fox ◽  

1971 ◽  
Vol 23 (2) ◽  
pp. 245-272 ◽  
Author(s):  
Pi-Chao Chen

Some economists argue that high population density and rapid population growth are not in themselves impediments to economic development. On the basis of a quantitative analysis of historical data, Simon Kuznets, for instance, concludes that, historically, rates of economic development have not significantly correlated, either positively or negatively, with rates of population growth. Similarly, E. E. Hagen observes that “nowhere in the world has population growth induced by rising income been sufficient to halt the rise in income. … The historical record indicates that rise in income in these societies has failed to occur not because something thwarted it, but because no force has been present to cause income to rise.


1985 ◽  
Vol 12 (3) ◽  
pp. 425 ◽  
Author(s):  
NP Brothers ◽  
IJ Skira ◽  
GR Copson

246 feral cats were shot on Macquarie Island, Australia, between Dec. 1976 and Feb. 1981. The sex ratio ( males : females ) was 1:0.8. The percentages of animals with tabby, orange and black coats were 74, 26 and 2 resp. [sic]. Of the 64 orange cats, 56 were males . The breeding season was Oct.-Mar., with a peak in Nov.-Dec. The number of embryos in the 14 pregnant females averaged 4.7 (range = 1-9). The size of the 23 litters that were observed averaged 3 (range = 1-8). Kitten survival to 6 months of age was estimated to be <43%.


Author(s):  
Shalin Hai-Jew

One degree out from an image “selfie” are text-based self-generated user profiles (self-portrayals) on social media platforms; these are self-depictions of the individual as he or she represents to the world. This work-based self-representation must be sufficiently convincing of professionalism and ethics to encourage other professionals to collaborate on shared work projects through co-creation, support, attention, or other work. While project-based track records may carry the force of fact, there are often more subtle messages that have high impact on distant collaborations. One such important dimension is “indirect reciprocity,” or whether the target individual treats collaborators with respect and care and returns altruistic acts with their own acts of altruism. This work describes some analyses of professional profiles on social media platforms (email, social networking, and microblogging) for indicators of indirect reciprocity.


2011 ◽  
pp. 111-120
Author(s):  
Janet Toland ◽  
Fuatai Purcell ◽  
Sid Huff

All governments face difficulties in trying to ensure the full participation of every citizen. The further a citizen is located from the centre of power and administration, such as a capital city, the less engaged they are likely to be. This phenomenon can be observed at both a national and an international level. At the global level countries located in close proximity to major world markets are more likely to have well-developed e-government services, than more marginally located countries, particularly those with low population densities. Within individual countries, there is typically a marked variation between rural and urban areas both in terms of access to available infrastructure and uptake by citizens (Parker, 2000). In general, the more remote the location and the smaller the population density, the lower the rate of participation will be. This can be observed in even in the most highly developed, highly populated countries; for example, the Japanese government struggles to provide the often elderly residents of remote islands with government services (Hayashi & Hori, 2002). In a country that is less developed without easy access to major world markets, the effects on rural citizens are intensified. The small island developing states of the South Pacific are some of the most remotely located nations in the world; their economies are relatively underdeveloped and they have low population densities. By researching the difficulties faced in attempting to implement e-government in some of the most distant corners of the earth, lessons can be learned about the way that information and communication technologies (ICTs) can overcome the barriers of geography. The insights gained from this exercise are relevant worldwide; as many economically developed countries also have pockets of population that are hard to reach. A counter argument is that some of these differences may be attributable to a country’s level of economic development rather than it’s actual geographic location. A notable example of a remotely located country that has a highly developed e-government system is New Zealand. Despite having only four million inhabitants, and being placed on the other side of the globe from the major world markets of Europe and the USA, in 2001 New Zealand was nominated by the UN as the country with the third most advanced e-government system in the world (Boyle & Nicholson, 2003). ICTs now make it possible to connect a citizen in even the most far-flung location directly to central government services. This article investigates the status of e-government in remote locations. Representatives from ten different South Pacific Islands were surveyed to discover what they perceived as the main barriers and opportunities in developing e-government in each of their different countries. The island states of the South Pacific have developed independently and are culturally diverse. However, they all share some common features with regards to adoption of ICTs. In order to appreciate these factors more fully, one country, Samoa, has been used as an example. By comparing Samoa with New Zealand, lessons can be learned about how to utilise ICT to overcome the disadvantages of distance and low population. E-government is sometimes viewed as a subset of e-commerce. However, it needs to be remembered that there are substantive differences between the private and public sectors. Governments have a duty to make sure that services are available to all citizens, and usually the citizens who are the most needy are those who have the least access to government services (Curthoys & Crabtree, 2003). Often this is because such citizens live in remote rural locations. The public sector is a law-based system, and government includes many processes that are different from processes encountered in private sector settings such as retail or banking, for example: complex decision making; negotiations between stakeholders; policy formulation; and democratic participation (Lenk, 2002). An example is the highly contentious issue of land ownership in the South Pacific; the use of e-government could potentially help land boards to demonstrate a fair and transparent approach to this issue.


2020 ◽  
Author(s):  
Melissa Cate Christ ◽  
Hendrik Tieben

With one of the highest population densities in the world, Hong Kong suffers from a lack of public open space. Despite this situation, open spaces provided by government authorities or private developers often do not meet residents’ needs or include residents in the planning and design process. To explore one way that this issue is being addressed, this chapter describes an ongoing placemaking project within Hong Kong’s interstitial network of laneways (里) and alleys (巷). The key historical, sociocultural, and physical features, opportunities, and constraints of these in-between spaces are discussed. This is followed by an in-depth exploration of the case study Magic Lanes, a pilot project that aims to provide more inclusive public open spaces through placemaking and community co-creation.


2020 ◽  
Author(s):  
Sarara Azumi ◽  
Yuya Watari ◽  
Nariko Oka ◽  
Tadashi Miyashita

Abstract Understanding how invasive predators impact native species is essential for the development of effective control strategies, especially in insular environments where alternative non-native prey species exist. We examined seasonal and spatial shifts in diet of feral cat Felis silvestris catus focusing on the predation on native streaked shearwaters, Calonectris leucomelas, and introduced rats, Rattus rattus and R. norvegicus, which are alternative prey to shearwaters, on Mikura Island, Japan. Streaked shearwaters breed at low elevations on the island from spring to autumn, whereas rats inhabit the island throughout the year, which makes them an alternative prey when native shearwaters are absent. Fecal analysis revealed that feral cats dramatically shifted their diets from introduced rats in winter to streaked shearwaters in seabird-season in low elevation areas of the island, while cats preyed on rats throughout the year at high altitudes on the island. This finding suggests that feral cats selectively prey on shearwaters. This is probably because of their large body size and less cautious behavior, and because introduced rats sustain the cat population when shearwaters are absent. The number of streaked shearwaters killed was estimated to be 313 individuals per cat per year, which represents an indication of top-down effects of feral cats on streaked shearwaters. Further studies on the demographic parameters and interspecific interactions of the three species are required to enable effective cat management for the conservation of streaked shearwaters on this island.


Sign in / Sign up

Export Citation Format

Share Document