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THE ECOLOGY OF FERAL CATS, FELIS CATUS, IN OPEN FOREST IN NEW SOUTH WALES: INTERACTIONS WITH FOOD RESOURCES AND FOXESMOLSHER, Robyn Lorraine January 1999 (has links)
ABSTRACT Despite increasing evidence for the impact of feral cats Felis catus on native fauna in Australia, little is known of the ecology of cats, particularly factors that limit cat abundance. The ecology of the feral cat in Australia is represented by just 15 published studies on diet, only one of which has examined diet in relation to prey availability, and one study of home range behaviour. The red fox Vulpes vulpes is a significant pest to agriculture and native fauna in Australia and widespread fox removals have been proposed by the Vertebrate Biocontrol Cooperative Research Centre (VBCRC). However, there is concern that feral cats may increase compensatorily when fox populations are reduced, as has occurred in Western Australia, and therefore that predation pressure may not be alleviated on native fauna following fox control programs. This thesis is divided into two parts. First, the diet and home range size of cats is examined in relation to prey availability, and home range overlap and habitat use are determined. In the second part, several niche parameters (diet, home range and habitat use) that were potentially important resources for foxes and cats were quantified to assess the potential for competition. Avoidance and aggression between cats and foxes was examined using simultaneous radiotracking techniques and video observations. The hypothesis that foxes limit cats through interspecific competition (exploitation and interference) was then tested using a fox removal experiment. Finally, three further hypotheses were tested using a fox removal experiment to determine which factors limit feral cats at Burrendong. The four hypotheses tested were thus: i) Cats are limited independently of foxes through other factors such as food availability; ii) Foxes limit cats through interspecific competition (exploitation and/or interference); iii) Foxes limit cats through intraguild predation; iv) Cats benefit from the presence of foxes through facilitation. The diets and spatial use of feral cats were examined on agricultural land on the eastern shore of Lake Burrendong, New South Wales (32o40�S, 149o 10�E) between July 1994 and June 1997. The major land use for the area is water catchment under the agistment of sheep Ovis aries and cattle Bos taurus. The study area encompasses about 90 km2 of hilly terrain with undulating slopes that extend down to a flat foreshore area that has been extensively cleared of trees for grazing. The slopes are generally well timbered and dominated by white box Eucalyptus albens woodlands with some yellow box E. melliodora associations. Stands of cyprus pines Callitris spp. are also common. Feral cats and red foxes are established throughout the study area, and the European rabbit Oryctolagus cuniculus was abundant until the arrival of Rabbit Calicivirus Disease (RCD) in June 1996. The diet of feral cats was determined from the analysis of 499 scats. Rabbits were the staple prey of cats, with occurrence (O) in 81.6% of scats and comprising 68.4% by volume (V). Carrion (mostly eastern grey kangaroo Macropus giganteus and sheep) (O 21.5%, V 11.5%) was an important secondary food, particularly in winter and spring. Other mammalian prey included brushtail possums Trichosurus vulpecula (O 4.6%, V 2.4%), house mice Mus domesticus (O 6.2%, V 3.2%), black rats Rattus rattus (O 2.6%, V 1.4%) and a dunnart Sminthopsis sp. (probably S. murina) (O 0.2%, V 0.006%). Invertebrates (mostly Orthopterans) (O 41.5%, V 7.5%), vegetation (O 26.3%, V 3.6%), birds (O 4.2%, V 0.8%) and reptiles (O 3.4%, V 0.3%) were generally of minor importance in the diet. Few significant seasonal differences were found, although invertebrates contributed significantly less, and possums more, to the mean scat volume in winter and summer respectively. A significant dietary response was found for changes in rabbit abundance, but not for the other prey groups. Cats continued to prey heavily on rabbits after the arrival of Rabbit Calicivirus Disease, despite the relatively low numbers of rabbits. Ten months post-RCD, house mice increased in importance in the diet. However, it was not known whether this represented prey switching sensu stricto or opportunistic predation on an increased mouse population, as mouse abundance was not measured during this period. Seventy-seven cats (48 recaptures) were caught in 6762 trap nights between November 1994 and August 1996 using both cage traps and leg-hold traps. A further 18 individual cats were trapped as non-target animals by the VBCRC Fox Sterility Project and used in this study. Trapped adult cats were fitted with radio collars and their home range size, overlap and habitat use examined. Home ranges and core areas were quantified using 95% and 50% kernel utilisation distributions (KE 95 and KE 50) and minimum convex polygons (MCP 100, MCP 95, MCP 50). Four habitat types (grassland, open woodland, open forest, and mudflats) were delineated on aerial photographs and a habitat map produced using ARC/INFO. Compositional analysis was used to examine habitat preference in cats. Home range sizes of cats (n = 15, 598 fixes) in winter 1995, prior to fox removal, were similar to those reported in the only published study of cat spatial use in Australia, but larger than those recorded elsewhere. This may have reflected more dispersed food resources in Australia, although home range size was not correlated significantly with rabbit abundance. Male ranges (MCP 95 = 284 ha, n = 11) tended to be larger than females ( = 151ha, n = 4), but no differences were detected between young (1-3 years, = 271ha, n = 7) and old (>3 years, = 221ha, n = 8) cats. Cats were active both by day and night with no temporal differences being detected in range size. Both adult male and female cats tended to be solitary, although home ranges overlapped extensively. Kin groups were indicated (but not confirmed) as most inter-sexual overlap occurred between young and old cats. Habitat composition of home ranges generally reflected the availability of habitats at the study site, although cats significantly avoided mudflats. Home ranges comprised mostly open woodland and open forest habitats with smaller areas of grassland and mudflats. However, within individual home ranges, cats used grassland and open woodland habitats most often where rabbits were more abundant. Inter-individual (sex, age) or temporal (day/night) differences in habitat use were not detected. Comparison of resource use between cats and foxes indicated a large overlap in diet, home ranges and habitat use. Dietary breadths and overlaps between cats and foxes increased when rabbit availability declined in autumn and post-RCD. Dietary overlap was high overall (75%), although some resource partitioning was detected. Rabbits were more important in the diet of cats than foxes, particularly in summer, when foxes ate more grasshoppers. Carrion, invertebrates and vegetation were more important for foxes than for cats overall. Home ranges of both cats and foxes comprised mostly open woodland habitats followed by grassland, open forest and mudflats, which largely reflected their relative availabilities. However, within individual home ranges, cats showed a preference for grassland habitats. In addition, cats tended to deposit scats more often than foxes at rabbit warrens and at hollow log entrances, while foxes deposited scats more often than cats on sand plots, tracks and at dams. The large overlap in resource use between cats and foxes indicated a high potential for exploitation competition. Foxes may attempt to lessen competition by killing cats (interference competition). Three radiocollared cats were killed by foxes and aggression was observed toward cats. Home ranges overlapped extensively, but avoidance was indicated from the simultaneous radiotracking of both predators, as greater separations and lower overlaps in home ranges and core areas were recorded between species than within species. In addition, video observations suggested avoidance of carcasses by cats in the presence of foxes. The hypothesis that foxes limit feral cats through interspecific competition was then tested using a fox removal experiment. Foxes were reduced at two of the four sites from October 1995 using �1080� baiting and spotlight shooting by the VBCRC Predator-Prey project. Resource use and abundance of cats were compared before and after fox removal and between treated and untreated sites. Although no increase in cat abundance followed the removal of foxes, significant behavioural changes by cats strongly suggested interspecific competition operating via exploitation and interference. Exploitation competition was supported by the increased consumption of carrion by cats at the treated sites after fox removal, while support for interference competition came from the increased use of grassland habitats at night after fox removal. The direction of the resource shifts to more prey-rich habitats indicated asymmetry in the relationship between the two predator species. Although the null hypothesis of no limitation of cats by foxes could not be rejected, as no increase in cat abundance was recorded after fox removal, interspecific competition was considered to be the most likely mechanism limiting feral cats at Burrendong. Intraguild predation was not indicated as no cat remains were found in any of the 343 fox scats or 255 fox stomachs that were examined. In addition, minimal evidence was found for facilitation between cats and foxes, or for food limitation. The potential for foxes to limit cats, as shown in this study, indicates that cats need to be considered in future fox control operations. Integrated pest management, where foxes, cats and rabbits are controlled together, is strongly proposed if the objective is to safeguard native fauna in Australia. Further research is required to improve the effectiveness of current techniques for censusing cat populations, particularly in forested areas. This is essential for monitoring the effectiveness of control campaigns and quantifying factors that limit cat populations, and ultimately for effective protection of susceptible native fauna.
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The quality and nutritive value of meat from male Boer and Australian feral goats /Pratiwi, Ni Made Werdi. January 2005 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.
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Olfactory and Behavioural Regulation of Territorial Aggression in Feral Rats (Rattus norwegicus)Alberts, Jeffrey R. 10 1900 (has links)
<p> This thesis is primarily concerned with the problem of recognition among feral Norway rats. Wild rats are known to behave amicably in the presence of colony members and act in a stereotyped aggressive manner towards unfamiliar conspecifics in a territorial context. Previous reports suggest that identity is basically olfactory and is organized around colony-specific odors residing in the nesting material or the metabolic excretions of the male members of a colony.</p> <p> The first experiments in this study were attempts to replicate various reports concerning the maleability of clan odors, thereby giving a wild rat the olfactory characteristics of an alien group and, conversely, to alter a resident's odor such that he was no longer identifiable as a member of his original clan. Further experiments examined identifier and regulator functions of behavioural cues on social interaction subsequent to recognition. The interactions of unfamiliar rats on a mutually common terrain was studied, and compared with that of familiar rats paired on an uncommon territory. The final experiment investigated the functional nature of olfactory stimulation in these situations and compared the reactions of anosmic residents towards familiar and unfamiliar conspecifics.</p> <p> These experiments indicate that recognition is indeed an olfactory process but that identity is highly resistent to alteration. The identifier substance does not appear to be contained in either the nesting matter nor in a colony's urine or feces. Bond of familiarity are not specific to a common terrain and in most cases behavioural cues appear to control the onset and termination of fight behaviour following the olfactory identification. Studies of anosmic residents indicate that novel odors elicit aggressive tendencies while familiar odors are not inhibitors of aggression. The results suggest the presence of a specific male pheromone that is essential for the arousal of aggression while the topography of interaction is regulated largely by the reciprocal behaviours of the animals.</p> / Thesis / Master of Arts (MA)
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Feral hogs in central Mississippi:home range, habitat use, and survivalHayes, Robert Clay 05 May 2007 (has links)
I examined home range, habitat use, and survival of 29 feral hogs in central Mississippi using radio telemetry. During the dry season (1 April - 31 October 2005), densely-vegetated habitats were very important in home range placement (2nd-order selection) with selection favoring seasonallylooded old fields, followed by old fields and managed openings. During the wet season (1 November 2005 - 31 March 2006), old fields were still preferred followed by agricultural fields, but flooded old fields were not preferred. For habitat selection within the home range (3rd-order selection), hogs preferred old fields and managed openings during the dry season. All habitats were used randomly within home ranges during the wet season. Dry and wet season survival rates were 80.8% and 41.4%, respectively. Hunting was the major cause of mortality (80 ? 100%). Seasonal differences in habitat selection may have been caused by flooding of preferred habitats, food availability and hunting.
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Territoriality and habitat selection of feral pigs on Fort Benning, Georgia, USASparklin, William DeRoche. January 2009 (has links)
Thesis (MS)--University of Montana, 2009. / Contents viewed on November 25, 2009. Title from author supplied metadata. Includes bibliographical references.
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The ecology and management of feral cat colonies : a survey of feral cat colonies in Great Britain and an experimental field study of the effect of neutering on the ecology, behaviour and social organisation of a single colonyRees, Paul Anthony January 1982 (has links)
A postal questionnaire survey located over 700 feral cat colonies. Most were small well - established and lived in association with man, The feral cat population of Britain was estimated to be one million and is concentrated in urban areas. A domestic cat survey indicated a total population of 5.9 million cats in Britain. There appeared to be more females than males and a higher proportion of females than males were neutered. The effect of neutering on a colony of 30 adult cats. living in the grounds of Winwick Hospital, Cheshire, was examined. Individual cats were recognised by differences in coat colour and pattern, and data were collected by direct observation. The colony was studied for one year before and one year after neutering. Before neutering there appeared to be a seasonal fluctuation in numbers as a result of natality$ mortality and migration. Male immigrants were recorded. After neutering the colony remained stable in size and only one (female) immigrant was observed. The ecology and behaviour of 19 cats were studied in terms of home range, the distribution of, sightings in time, and sociability. Before neutering cluster analysis was used to identify groups of similar cats: males$ femalesp nomads and residents, After neutering no such groups could be distinguished and it is suggested that this was a result of changes in hormone balance. A mathematical model was developed for the study of associations within populations. It was shown that the cats tended to form more discrete social groups after neutering with fewer movements between groups. The adult cats were generally in good condition but there was evidence of exposure to feline calicivirus and feline herpesvirus. Trapping of cats appeared to be efficient and humane, and neutering was considered to be an acceptable form of population management.
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Parasites of feral cats and native fauna from Western Australia the application of molecular techniques for the study of parasitic infections in Australian wildlife /Adams, John Peter. January 2003 (has links)
Thesis (Ph. D.)--Murdoch University, 2003. / Title from t.p. of PDF document (viewed on Apr. 17, 2005). Includes bibliographical references (p. 195-239).
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The ecology and management of feral cat colonies. A survey of feral cat colonies in Great Britain and an experimental field study of the effect of neutering on the ecology, behaviour and social organisation of a single colony.Rees, Paul Anthony January 1982 (has links)
A postal questionnaire survey located over 700 feral cat colonies.
Most were small well - established and lived in association with man,
The feral cat population of Britain was estimated to be one million and
is concentrated in urban areas.
A domestic cat survey indicated a total population of 5.9 million
cats in Britain. There appeared to be more females than males and a
higher proportion of females than males were neutered.
The effect of neutering on a colony of 30 adult cats. living in the
grounds of Winwick Hospital, Cheshire, was examined. Individual cats
were recognised by differences in coat colour and pattern, and data were
collected by direct observation. The colony was studied for one year
before and one year after neutering.
Before neutering there appeared to be a seasonal fluctuation in
numbers as a result of natality$ mortality and migration. Male immigrants
were recorded. After neutering the colony remained stable in size and
only one (female) immigrant was observed.
The ecology and behaviour of 19 cats were studied in terms of home
range, the distribution of, sightings in time, and sociability. Before
neutering cluster analysis was used to identify groups of similar cats:
males$ femalesp nomads and residents, After neutering no such groups could
be distinguished and it is suggested that this was a result of changes
in hormone balance.
A mathematical model was developed for the study of associations
within populations. It was shown that the cats tended to form more
discrete social groups after neutering with fewer movements between
groups.
The adult cats were generally in good condition but there was
evidence of exposure to feline calicivirus and feline herpesvirus.
Trapping of cats appeared to be efficient and humane, and neutering
was considered to be an acceptable form of population management. / Royal Society for the
Prevention of Cruelty to Animals. The Feral Cat Working Party.
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Zjišťování početního stavu populace městského holuba (Columba livia f.domestica) ve vybraných lokalitách a v letovém koridoru Radlického údolí v Praze / Census of the Feral Pigeon (Columba livia f. domestica) Population in the Selected Localities and Flying Corridor of the Radlické Valley in PragueŠtěpán, Jiří January 2014 (has links)
Census of the feral pigeon (Columba livia f. domestica) population in the selected localities and flying through the corridor of the Radlické valley in Prague. The diploma thesis is dealing with the research of the number of the pigeons (Columba livia f. domestica) flying through the corridor of the Radlické údolí, with the exploration of the next pigeons' flying routes, with inventorying of the number of pigeons in the localities Smíchovské nádraží and Na Knížecí and with dependece of the number of pigeons on the abiotical conditions, season, day time and the time of the spring seeding and harvest. The food ecology of pigeons was also investigated within the process of inventorying in the locality Na Knížecí. The final chapter is focused on coloring of the individuals in the different Prague localities. The research was realised from July 2012 to November 2013. The folowing methods of research were used: observation, marking with the wing tapes, modified linear method of addition. The results of the diploma thesis indicate that number of pigeons in the observed localities change especially in the time of seeding and harvest. Numerical fluctuations are not so extreme because the group of the resident pigeons always stays in the city. The spectrum of the food offered by local inhabitants doesn't...
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Feral buffalo in Kakadu National Park : survey methods, population dynamics and controlSkeat, Andrew, n/a January 1990 (has links)
(1) Aerial survey methods for estimating
population size of feral water buffalo in northern
Australia were examined.
(2) Line transect models underestimated population
size. Of six models tested the most accurate
underestimated by nearly half. The models give
biased estimates most probably because not all
animals on the survey line were sighted .
(3) Aerial strip transect surveys were also
negatively biased. The extent of this bias was
estimated in index-removal experiments.
Experiments were carried out on two populations in
areas of differing obstructive canopy cover.
(4) In woodland habitat with a canopy cover of 30-
60%, a correction factor of 3.2 was required to
take account of animals not seen. In forest
habitat with a canopy cover of 60-100%, a
correction factor of 4.9 was required.
(5) Using these results, the population size of
feral buffalo, cattle and horses in Kakadu National
Park was estimated by aerial survey at the end of
each year over 6 years. Annual rates of increase
for three regions of the Park were estimated,
taking into account known removals from the
population. The effects of dry season rainfall and
population density in the preceding year on rate of
increase were examined for each species.
(6) The mean annual exponential rate of increase
for each species was 0.10 yr-1 for buffalo, 0.23
yr-1 for cattle and -0.14 yr-1 for horses.
(7) The annual rates of increase varied greatly
between years within all species and were highly
correlated with dry season rainfall in the year of
survey for buffalo and cattle but not for horses.
(8) No significant effect of preceding density on
rate of increase was found for any species. A
large reduction in buffalo populations did not
correspond with an increase in unharvested
populations of horses, suggesting the two species
do not compete for food or other resources.
(9) A campaign to control populations of feral
water buffalo in Kakadu National Park was assessed.
Between 1979 and 1988, approximately 79,000 animals
were removed, 54% by commercial live-capture, 35%
by shooting from helicopters and 10% by shooting
from the ground.
(10) In the period 1983-1988 when population
estimates from aerial survey are available, mean
buffalo population density was reduced from
5.60 km-2 to 1.17 km-2 over the surveyed area of
the Park.
(11) The costs of removal by shooting from
helicopters, capturing animals alive and shooting
from the ground were compared. The mean costs per
animal in 1988 were $24.13, $74.53, and $86.02
respectively.
(12) The effects of initial density and time spent
shooting on number of animals removed by shooting
from helicopters were examined. One linear and two
curvilinear models were fitted to data from four
different removal exercises. The relationship
between time spent shooting and number removed was
best described by a curvilinear (Ivlev) function.
This model was used to estimate costs of control to
a specified density.
(13) Model regression coefficients differed
between removal exercises, suggesting that the
number removed may be affected by variables other
than time spent shooting and initial density. Data
from the range of conditions encountered during
removal is thus likely to be required for robust
estimation of removal costs.
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