Mammalian predators have been liberated on many islands to control pests but the desired results have rarely been achieved. The liberation of mongooses on islands in the Caribbean and Pacific is an excellent example of a liberation which had serious repercussions. These were liberated to control rats which caused serious damage in the sugar cane fields and although they reduced the numbers of rats, they also exterminated many species of small mammals and birds. Stoats, ferrets and weasels were liberated in New Zealand in the early 1880's to control rabbits. They appear to have had little effect on rabbit populations and stoats quickly spread into forest areas. It is not now possible to determine the effect these predators had on the native bird populations as the changes in fauna and habitat were complex. Unfortunately no studies of mustelids were made until 1948 when Wodzicki (1950) made a brief study as part of his survey of introduced mammals in New Zealand. The two periods of greatest change for mustelids have been during their spread throughout the country in the 1880's and in the early 1950's when rabbits were successfully controlled. There is little information on changes in density or feeding habits of mustelids during these times. Detailed investigation of the ecology of mustelids in New Zealand was begun by Dr W.H. Marshall, Fulbright Research Scholar from the University of Minnesota, with Animal Ecology Division, D.S.l.R. from September 1960 until June 1961. He examined their ecology in the light of his experience of mustelids in North America where conditions differ markedly from those in New Zealand. I joined Animal Ecology Division in November 1960 to assist Dr. Marshall throughout the remainder of his study, and continued the work after his return to the United States. The ecology of stoats, ferrets and weasels has been investigated in terms of their adaptation to food supplies which differ markedly from those in their native range in the Northern Hemisphere.

Mammalian predators have been liberated on many islands to control pests but the desired results have rarely been achieved. The liberation of mongooses on islands in the Caribbean and Pacific is an excellent example of a liberation which had serious repercussions. These were liberated to control rats which caused serious damage in the sugar cane fields and although they reduced the numbers of rats, they also exterminated many species of small mammals and birds. Stoats, ferrets and weasels were liberated in New Zealand in the early 1880's to control rabbits. They appear to have had little effect on rabbit populations and stoats quickly spread into forest areas. It is not now possible to determine the effect these predators had on the native bird populations as the changes in fauna and habitat were complex. Unfortunately no studies of mustelids were made until 1948 when Wodzicki (1950) made a brief study as part of his survey of introduced mammals in New Zealand. The two periods of greatest change for mustelids have been during their spread throughout the country in the 1880's and in the early 1950's when rabbits were successfully controlled. There is little information on changes in density or feeding habits of mustelids during these times. Detailed investigation of the ecology of mustelids in New Zealand was begun by Dr W.H. Marshall, Fulbright Research Scholar from the University of Minnesota, with Animal Ecology Division, D.S.l.R. from September 1960 until June 1961. He examined their ecology in the light of his experience of mustelids in North America where conditions differ markedly from those in New Zealand. I joined Animal Ecology Division in November 1960 to assist Dr. Marshall throughout the remainder of his study, and continued the work after his return to the United States. The ecology of stoats, ferrets and weasels has been investigated in terms of their adaptation to food supplies which differ markedly from those in their native range in the Northern Hemisphere.

This project aimed to reanalyse two large historical data sets from two different locations in New Zealand (Fiordland in the South Island and Pureora Forest Park in the North Island). The data describe populations of mice (Mus musculus), rats (Rattus rattus and R. norvegicus), and stoats (Mustela erminea) collected using standard monitoring techniques from five distinct types of forest habitat. The new analysis methods selected were an index of patchiness and Site Occupancy analysis. The objectives of the analysis were (1) to evaluate whether the patchiness index and Site Occupancy analysis methods might contribute to improved protocols for monitoring small mammal populations in the future, and (2) to use formal tests of five hypotheses to evaluate two of the assumptions made by the conventional density index often used in small mammal studies. I describe the results of the analyses for each species, including any problems encountered (such as the inability of the Site Occupancy method to analyse very sparse data sets). I also describe the results pooled from each of the two study locations and potential consequences for small mammal monitoring and control. This analysis has suggested that in most cases the density index is not a rigorous measure of small mammal populations. However, both the index of patchiness and Site Occupancy analysis provided useful, new information about these populations of rodents and stoats, despite the fact that these historical data sets were not designed for use with modern methods of analysis. Please note: some figures and tables were printed separately and added to the thesis as unnumbered pages. These can be found in the file 03Plates_and_Tables.pdf.

Data derived largely from ecclesiastical (mostly churchwardens') accounts, foxhunting statistics, local scientific society records and 19th and 20th century literature sources from a wide range of published material, have provided detailed evidence of the status and changes in distribution over the past four centuries in Yorkshire for fox (Vulpes vulpes), badger (Meles meles), otter (Lutra lutra), pine marten (Martes martes), stoat (Mustela erminea), weasel (M. nivalis), polecat (M. putorius), American mink (M. vison), wildcat (Felis silvestris) and domestic cat (Felis catus). In the case of the domestic cat, questionnaire surveys quantified population sizes and predatory activity in rural, suburban and urban situations. Evidence of the former distribution of all the carnivores studied provides a credible historical basis for biodiversity action planning and the substantial archived database and bibliography provide further research opportunities.

Data derived largely from ecclesiastical (mostly churchwardens¿) accounts, foxhunting statistics, local scientific society records and 19th and 20th century literature sources from a wide range of published material, have provided detailed evidence of the status and changes in distribution over the past four centuries in Yorkshire for fox (Vulpes vulpes), badger (Meles meles), otter (Lutra lutra), pine marten (Martes martes), stoat (Mustela erminea), weasel (M. nivalis), polecat (M. putorius), American mink (M. vison), wildcat (Felis silvestris) and domestic cat (Felis catus). In the case of the domestic cat, questionnaire surveys quantified population sizes and predatory activity in rural, suburban and urban situations. Evidence of the former distribution of all the carnivores studied provides a credible historical basis for biodiversity action planning and the substantial archived database and bibliography provide further research opportunities.

Using trap data the Hawdon, Poulter and South Branch valleys, a spatial distribution model was created for Stoats (Mustela erminea), Ship Rats (Rattus rattus) and Weasels (Mustela nivalis) in the North Branch of the Hurunui River. Ten spatial attributes were analysed in this thesis as potential spatial predictors of Stoats, Ship rats or Weasels; four of which were distance related measurements (distance from ecotonal edge, distance from river, distance from river tributary and distance from trapping edge); three were climate based variables (mean maximum temperature, mean minimum temperature and mean precipitation) and three were topographical based variables (elevation, aspect and slope). Relationships that existed between each spatial attribute and the number of Stoats, Ship Rats and Weasels caught were quantified by comparing the significance of the mean trapping rate with each spatial attribute and expressed spatially as maps in a Geographical Information System (GIS). Results from this thesis found elevation, aspect and distance from ecotonal edge as potential spatial predictors of Stoat populations. Elevation and aspect were found to be potential predictors of Ship rat and Weasel populations. GIS is able to predict the spatial distribution of pest species to a similar (or better) level compared to more formal associative models. The potential of GIS is however, restrained by the same limitations associated with these models. By using a larger trapping data set and identifying a number of social interactions between Stoats, Ship Rats and Weasels, one can improve the accuracy of spatially modelling each species within a Beech forest environment. Therefore, improve our understanding how landscapes influence the distribution of each pest species.

Using trap data the Hawdon, Poulter and South Branch valleys, a spatial distribution model was created for Stoats (Mustela erminea), Ship Rats (Rattus rattus) and Weasels (Mustela nivalis) in the North Branch of the Hurunui River. Ten spatial attributes were analysed in this thesis as potential spatial predictors of Stoats, Ship rats or Weasels; four of which were distance related measurements (distance from ecotonal edge, distance from river, distance from river tributary and distance from trapping edge); three were climate based variables (mean maximum temperature, mean minimum temperature and mean precipitation) and three were topographical based variables (elevation, aspect and slope). Relationships that existed between each spatial attribute and the number of Stoats, Ship Rats and Weasels caught were quantified by comparing the significance of the mean trapping rate with each spatial attribute and expressed spatially as maps in a Geographical Information System (GIS). Results from this thesis found elevation, aspect and distance from ecotonal edge as potential spatial predictors of Stoat populations. Elevation and aspect were found to be potential predictors of Ship rat and Weasel populations. GIS is able to predict the spatial distribution of pest species to a similar (or better) level compared to more formal associative models. The potential of GIS is however, restrained by the same limitations associated with these models. By using a larger trapping data set and identifying a number of social interactions between Stoats, Ship Rats and Weasels, one can improve the accuracy of spatially modelling each species within a Beech forest environment. Therefore, improve our understanding how landscapes influence the distribution of each pest species.

The human use of landscape causes fragmentation and loss of original habitats. Different species vary in their sensitivity to habitat loss. Especially carnivores can be more sensitive to decrease of their habitat because of lower abundance of their prey. On the other hand several opportunistic carnivores can profit in human modified habitats. This study was carried out in the České Budějovice basin, Czech Republic during the years 2008 and 2009 and the aim of this study was to determine carnivore{\crq}s habitat preferences in the fragmented landscape. During these two years were seven carnivore species monitored in forest patches by using scent stations. Records of this monitoring were compared with physiognomy of these patches and structure of surrounding landscape.