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'Visions of wildness' : the place of (re)wilding in Scotland's uplandsDeary, Holly Angela January 2014 (has links)
Notions of ‘wildness' are increasingly relevant to upland management discussions in the Scottish Highlands as several conservation-focused estates embrace a ‘wildland management ethos'. However, while a range of wildland conservation initiatives have embarked upon pathways towards ‘rewilding', this research demonstrates that, although members of this creative conservation movement are widely perceived to share a common vision, they prioritise markedly different wildland qualities. Through a series of triangulated phases, this research explores this ‘spectrum of wildness' and examines the conceptual coherence of wildland restoration discourses. Twenty semi-structured scoping interviews with key stakeholders associated with Scotland's wildest places provide the foundations for an adapted Delphi model, incorporating a Q-methodology study, which utilises insights from seventeen large upland land-holdings to interrogate the disparate discourses associated with Scotland's emergent wildland movement. A taxonomy of management approaches is presented based upon (i) different conceptions of ‘wildness', (ii) differing degrees of concern for ecological and cultural integrity, (iii) conflicting beliefs about the degree of management intervention appropriate and (iv) fundamentally divergent underlying environmental ideologies. A further twenty-three semi-structured interviews exploring wilderness restoration frameworks in the USA, New Zealand and parts of Europe provide an international perspective on Scotland's distinctive approach to wildland management and demonstrate the challenges of multi-dimensional wilderness frameworks which grow out of conflicting mandates; most notably, a critical faultline exists between restoring ‘wildness' (focussed on processes) and naturalness (focussed on endpoints). Given that practical tensions can arise from these different ideological perspectives, understanding and accommodating the social and cultural dimensions which shape multiple (re)wilding discourses is considered critical. As such, place-specific and endogenous social representations are called for, in which wild land is both a physical place and a cultural ideal, and in which (re)wilding comprises a heterogeneous mix of different wilds. This research also critically reflects upon how cultural landscapes with wild qualities present opportunities for rethinking the historical and cultural dimensions of established wilderness values. By exploring the framing of ‘wild' in Scotland's wildland initiatives, a postmodern wildlands narrative which negotiates the conceptual challenges of (re)wilding in a storied, cultural landscape is presented.
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Nesting behavior in a reintroduced population of California condorsSandhaus, Estelle A. 14 January 2013 (has links)
Studies in numerous animal taxa demonstrate that early rearing experience has a profound influence on the development of later adaptive behavior. This has implications for endangered species management, particularly when animals are reared in captivity for reintroduction or in cases in which species managers play an active role in managing animals at the individual or population levels. The California condor (Gymnogyps californianus) is a critically endangered New World vulture that was subject to a period of extinction in the wild followed by ongoing reintroduction in portions of its native range. Though the reintroduced population in southern California is largely adapting well, several obstacles to viability remain that are primarily anthropogenic in nature. The purpose of this study was to quantitatively assess nesting behavior of free-flying California condors in the southern California population to determine whether differences in parental care and nestling behavior are attributable to parental rearing conditions and experience. Hierarchical generalized linear modeling was used to analyze parent and chick activity budget data. Differences among condors were not detected in attendance patterns across either the egg or chick phases of nesting. Variation was not detected among chicks in proportion of time spent active and inactive during the early nestling phase. Variations among older nestlings in the proportion of time spent inactive were observed, with associations detected between inactivity, pair, visibility and season. The proportion of time that parents interacted with nestlings varied from nest to nest, with associations detected between interaction, visibility and season. Finally, potential pair-level variation in the propensity to bring microtrash to the nest was observed. It is concluded that while visibility is often overlooked in behavioral analyses, it is methodologically important to account for this variable in analyses of condor nestling behavior. Further, while some pair-level variation in allocation of care to nestlings is apparent, this appears to be a function of factors not related to individual developmental differences.
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The behaviour and adaptation of reintroduced chimpanzees (Pan troglodytes troglodytes) in the Republic of CongoFarmer, Kay H. January 2002 (has links)
Increasing and unsustainable demands on Africa's natural resources are having a profound effect on wild primate populations. Whilst wild populations are decreasing, numbers of orphaned primates, sanctuaries and attempts to reintroduce primates back to the natural environment, are increasing. Data were collected on the present status of African ape sanctuaries from questionnaires distributed to sanctuary managers. Across Africa there are 18 sanctuaries housing over 500 African great apes. Facilities and ideologies vary but the majority of sanctuaries profess a commitment to conservation through education, local capacity building, facilitating the enforcement of wildlife laws and other activities. From 1996 to 2001 the non-governmental organisation Habitat Ecologique et Liberte des Primates has released 37 wild-born chimpanzees(Pan troglodytes troglodytes) from an island sanctuary to mainland forest in the Conkouati-Douli National Park, Republic of Congo. Twenty-seven chimpanzees have been successfully reintroduced, three are known to have died and the status of seven remains unknown. This thesis investigated the behavioural adaptation of 15 of these released chimpanzees and reviews the reintroduction process employed. Analyses of post-release behavioural data revealed that activity budgets and diet were comparable to those of wild chimpanzees, and that seasonal variation influenced feeding behaviour and plant speciess election. The chimpanzees utilised both terrestrial and arboreal zones and all nested in trees. A number of recommendations are made for future reintroduction projects. These include selecting a release site that has no, or a low density of, wild conspecifics; developing a relationship of trust between chimpanzee and caretakers without excessive dependency; using the release site for pre-release training; use of radio telemetry; post-release support and monitoring. This study has revealed the many complex factors that are involved in the reintroduction process. Future attempts to reintroduce chimpanzees should be guided by the experiences and recommendations of the present study to maximise success.
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An ecological study of reintroduced Arabian oryx in the ʻUruq Bani Maʻarid Protected Area of the Kingdom of Saudi ArabiaStrauss, Willem Maartin. January 2003 (has links)
Thesis (M.S.)--University of Pretoria, 2003. / Includes bibliographical references (leaves 228-250).
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An ecological study of reintroduced Arabian oryx in the 'Uruq Bani Ma'arid protected area of the Kingdom of Saudi ArabiaStrauss, Willem Maartin 07 September 2005 (has links)
This study was conducted in the ‘Uruq Bani Ma’arid Protected Area, on the western edge of the ‘Rub al Khali of the Kingdom of Saudi Arabia. The dispersal of different groups of Arabian oryx Oryx leucoryx (Pallas, 1777) was investigated, along with the seasonal range use patterns of the animals. The dispersal distances from the release site stabilised after a period of one year. The animals show seasonal differences in their range use patterns, associated with changes in their mobility. The dynamics of the relationship between the oryxes and their habitat were investigated. The structure and the condition of the vegetation, as well as some climatic variables were important determinants of seasonal habitat use. The diurnal activity patterns of the animals correspond with that characteristic of ungulates generally and the animals showed seasonal changes in their feeding preferences. The productivity of the population was high during the study period, with 34 live births, while six of the reintroduced animals died. Population viability analysis, however, shows that the population is vulnerable over the medium term (100 years) and that management should target the juvenile and especially adult females as they are keys to population growth and recovery. / Dissertation (MSc (Wildlife Management))--University of Pretoria, 2006. / Centre for Wildlife Management / unrestricted
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Evaluation of the ecological impacts of beaver reintroduction on aquatic systemsLaw, Alan January 2014 (has links)
The extent and quality of freshwater systems is declining globally. Combined with past drainage, straightening and flow regulation, current systems are often functional but not pristine. Conservation, creation and restoration of freshwater systems is common but requires significant planning, resources and active monitoring and may only be a short-term solution to the long-term problem of destruction and loss of riparian zones. Beavers (Castor spp.) have the ability to create physical and biological habitat heterogeneity through the construction of woody debris dams, thereby restoring lost natural discontinuities in freshwater systems. Beavers may thus offer a natural, more passive solution to the need for wetland restoration or creation and the problem of homogenisation of watercourses. As such, numerous beaver reintroductions and introductions have been undertaken based in part on restoring this lost natural heritage. However, it is crucial to be able to predict the potential effects on existing biota of physical modifications by beavers to ecosystems, especially in the light of further population expansion, whilst also disentangling these effects from other influences, namely herbivory. The impact of beavers on aquatic systems was studied using a combination of field-based surveys and experiments, using aquatic plants and macro-invertebrates as indicators of hydromorphological changes and to quantify the effects of direct foraging. The research presented in this thesis demonstrates beaver adaptive foraging behaviours between terrestrial and aquatic habitats, whilst feeding highly selectively, optimally and opportunistically, using the white water lily (Nymphaea alba) as a model species. The effects of beaver foraging on the aquatic plant resource and diversity was low over short time spans (e.g. 1 year), but when selective foraging was assessed over greater time scales (e.g. 10 years) the effects of foraging were distinct. Significant changes in aquatic plant height, biomass, richness, diversity and composition were observed over this time period due to selective grazing on large rhizomatous species (e.g. Menyanthes trifoliata). These direct effects occurred even though changes in water levels, which are commonly believed to be the main driver of beaver influence on aquatic vegetation, were negligible. In a separate study in Sweden where beavers commonly constructed dams, with ponds then forming upstream, the aquatic plant and coleoptera species richness and composition differed in comparison to adjacent non-beaver created wetlands. Therefore, having a range of wetland types in the environment increases physical and biological heterogeneity creating unique niches that are exploited by disparate taxa. The construction of a series of dams within a single reach of stream flowing through a Scottish agricultural landscape also increased physical habitat diversity. Distinctive macroinvertebrate assemblages and modified functional diversity were associated with each dominant habitat type in the stream, resulting in increased landscape scale richness. The findings of this thesis confirm that beaver engineering and foraging has the potential to create unique and highly heterogeneous wetland and stream habitats within landscapes that enhances richness and diversity for multiple species groups. This thesis also supports part of the rationale for the trial reintroduction of beaver to Scotland that beavers can restore degraded habitats.
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Habitat use and diet selection of reintroduced white rhinoceros (Ceratotherium simum) in Pafuri, Kruger National ParkPedersen, Gayle 03 1900 (has links)
Thesis (MSc (Conservation Ecology and Entomology))--Stellenbosch University, 2009. / ENGLISH ABSTRACT: In 2005, six white rhinoceros (Ceratotherium simum) were reintroduced into Pafuri, in
the far northern section of Kruger National Park (KNP), South Africa, as part of a
large mammal reintroduction project. All six individuals were fitted with horn radio
transmitters. Rhinos have been absent from Pafuri for over a century, and this project
aimed to establish a breeding nucleus in the area. The aim of this study was to
monitor post-release movement and habitat use of these animals within the 203 km2
study area and assess the short term success of the re-introduction project as well as
the suitability of the five landscape types in Pafuri as a habitat for white rhinoceros.
Habitat suitability and selection was assessed at two ecological hierarchical scales: 1)
landscape system, analysed further down to the spatial scale of range and territory
establishment, and 2) feeding station for diet selection. Rhinos were tracked for 12
months and a database of 719 sighting records was compiled. These data were used to
determine the utilisation of and preference between the Pafuri landscape types, using
preference indices that compare utilisation versus availability. An a-LoCoH
nonparametric kernel method was used to calculate home ranges and utilisation
distributions of each rhino. Feeding surveys were attempted by backtracking along
fresh rhino feeding paths and recording the grass species present and eaten in 0.7 m x
0.7 m quadrats. Faecal samples were collected and analysed using microhistological
techniques and dietary composition was assessed for each rhino.
Landscape preference analyses showed that the rhinos favoured Colophospermum
mopane Shrubveld on calcrete in the dry season, and the Punda Maria Sandveld in the
wet season. The territory establishment of the dominant bull was substantially larger
(44.8 km²) than those of adult male rhinos in the rest of KNP. Ranging areas of the
mature females (17 – 25.4 km²), were consistent with sizes of previous studies. The
two sub-adults ranged far more extensively, establishing an 84.1 km² annual range
during the study period. The annual diet consisted of mostly perennial grass species,
with moderate grazing value species dominating for most of the year. Dietary
analyses showed that Schmidtia pappophoroides, Eragrostis superba, Enneapogon cenchroides,
Cenchrus ciliaris and Stipagrostis uniplumis were the primary grass species consumed.
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This study demonstrated that the Pafuri rhinos are behaving similarly to rhinos
established in other areas, with movements around the landscapes being primarily
influenced by rainfall and permanent water sources, and the high quality grazing that
is more abundant in the wet season. Their range and territory sizes were inevitably
large, for a low density area, but not uncommonly so. The most significant outcome
of this study was the preference shown for the Colophospermum mopane Shrubveld on
calcrete landscape that is classed as unique within South Africa, and was also ranked
as ‘avoided’ by the earlier KNP studies into landscape preferences of rhinos. The
grass cover in Pafuri, although sparse and very dry, contained a diversity of low to
high grazing value grasses that the rhinos appeared to exploit to the best of their
ability. The abundance of moderate grazing value species in their diets, and the low
number of low grazing value species suggests that they are maximising the
opportunities to graze on nutritious grasses when they are available. Our findings
suggest that the Pafuri area is suitable for the establishment of a small breeding
nucleus of white rhinos. The abundance of permanent water, in the form of springs,
is a great advantage however, the potential for bush encroachment into grasslands in
areas of such low rainfall needs to be considered if the population continues to grow
at the current rate. The birth of two new calves in 2008 confirms that these rhinos
have settled and adapted to their new habitat, and is a very promising sign for the
future of this increasing subpopulation. / AFRIKAANSE OPSOMMING: In 2005 is ses wit renosters (Ceratotherium simum) hervestig in Pafuri in die noordelike
gedeelte van die Kruger Nasionale Park (KNP), Suid-Afrika, as deel van ‘n groot
soogdier hervestigings projek. Al ses individue is gemerk met horing radioseintoestelle.
Renosters kom vir al meer as ‘n honderd jaar nie meer in Pafuri voor nie
en hierdie projek was daarop gemik om ‘n teel-nukleus in hierdie gesied te vestig. Die
doel van hierdie studie was om die verspreiding van die renosters na loslating en
habitat-gebruik binne die 203 km2 studie-omgewing te monitor, om die korttermyn
sukses van die hervestigings program te evalueer en ook te kyk na die gepastheid van
die vyf landskap-tipes in Pafuri as ‘n geskikte habitat vir die wit renosters.
Habitatgepastheid en seleksie is geëvalueer volgens twee ekologiese hiërargiese skale:
1) landskapsisteem, wat in meer resolusie tot die ruimtelike skaal van reikwydte en
omgewingsvestiging geanaliseer is, en 2) voedings-stasie vir dieet-seleksie. Renosters
is vir 12 maande gevolg en ‘n databasis wat 719 waarneming-rekords bevat, is
opgestel. Laasgenoemde data is gebruik om die gebruik en voorkeur vir die Pafuri
landskap tipes te bepaal met behulp van voorkeur-indikators wat die gebruik met
beskikbaarheid vergelyk het. ‘n a-LoCoH nie-parametriese kern metode is gebruik
om die reikwydte en gebruiksverspreidings van elke renoster te bereken.
Voedingsopnames is gedoen deurdat vars renoster voedings-paadjies terugwaarts
gevolg is en die grasspesies teenwoordig en waarop gevoed is, in 0.7 m x 0.7 m
kwadrante te bepaal. Mismonsters is versamel en geanaliseer deur gebruik te maak
van mikro-histologiese tegnieke en voedingswaarde-samestellings is vasgestel vir elke
renoster .
Landskapsvoorkeur analises dui daarop dat die renosters in die droë seisoen
Colophospermum mopane struikveld wat op kalkreet groei verkies en die Punda Maria
Sandveld in die reën seisoen. Die terrein vestiging van die dominanate bul was
aansienlik groter (44.8 km²) in vergelyking met die volwasse bul renosters in die res
van die KNP. Reikwydte van die volwasse koeie (17 – 25.4 km²) was
ooreenstemmend met dié van vorige studies. Die reikwydte van die twee subvolwassenes
het baie meer gevarieer, deurdat ‘n 84.1 km² jaarlikse reikwydte gedek
was binne die studie periode. Die jaarlikse dieet het meestal bestaan uit meerjarige
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grasspesies, met spesies met matige weidingswaarde wat oorheers vir meeste van die
jaar. Voedingswaarde analises dui daarop dat Schmidtia pappophoroides, Eragrostis
superba, Enneapogon cenchroides, Cenchrus ciliaris en Stipagrostis uniplumis die primêre gras
spesies was waarop gewei word.
Die studie het bewys dat die Pafuri renosters soortgelyke gedragspatrone vertoon het
as renosters in ander gevestigde gebiede, deurdat bewegings binne die landskap
hoofsaaklik beïnvloed word deur reënval en permanente waterbronne, asook die hoë
gehalte weidingsbronne beskikbaar gedurende die reën seisoen. Hulle reikwydte- en
terrein-groottes was uiteraardelik groot vir ‘n lae-digtheid areas, maar dit is nie
buitengewoon nie. Die mees betekenisvolle gevolgtrekking van die studie was die
voorkeur vir die Colophospermum mopane struikveld op kalkreet landskappe wat beskou
word as uniek aan Suid-Afrika, en wat ook beskou was as ‘vermy’ deur vroër KNP
studies tov. landskap voorkeure spesifiek vir renosters. Die grasbedekking in Pafuri,
alhoewel yl en baie droog, het tog oor ‘n verskeidenheid grasse beskik wat van lae tot
hoë weidings waarde het, en wat die renosters tot die beste van hulle vermoë benut
het. Die oorvloedige teenwoordigheid van beide spesies met matige weidingswaarde
in hulle dieët en die lae hoeveelheid van spesies met lae weidingswaarde, impliseer
dat hulle die geleentheid om op voedingsryke grasse te voed ten volle benut wanneer
dit beskikbaar is. Ons resultate dui daarop dat die Pafuri omgewing geskik is vir die
vestiging van ‘n klein teel-nukleus van wit renosters. Die oorvloedige
teenwoordigheid van permanente waterbronne in die vorm van fonteine is ‘n groot
voordeel, maar die kans vir bosindringing in hierdie grasveld-gebiede met lae reënval
moet oorweeg word sou die populasie aanhou toeneem teen die huidige tempo. Die
geboorte van twee nuwe kalfies in 2008 staaf die moontlikheid dat die renosters
gevestig en aangepas het in hulle nuwe habitat, wat ‘n baie belowende teken is vir die
toekoms van die groeiende subpopulasie.
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Ecological effects of the feeding and construction activities of the Eurasian beaver (Castor fiber) in Scotland : implications for reintroductionJones, Kevin Christopher January 2006 (has links)
Beavers have been described as a “keystone species” and “ecosystem engineers”, and in this dual role have great potential to physically modify their environment through tree-felling, foraging and construction activities. The resultant change in habitat heterogeneity can affect the flora and fauna that share the habitat with them. There has been recent interest in reintroducing the Eurasian beaver to the United Kingdom after an absence of over 400 years. To date, no research (aside from this thesis) has focussed on beaver ecology and behaviour in Scotland. This study has investigated the ecological effects of a small number of beavers in two enclosed but semi-natural Scottish sites at Bamff in Perthshire. The research conducted over a three-year period, with particular emphasis on the effects of tree-felling, foraging and construction activities. Trees were felled for both dietary and construction purposes, with felling rates being influenced by habitat availability, quality and the degree of habitat modification required. Highest rates were evident during the initial colonisation period of marginal sites (c. >300 trees / beaver / calendar year), and lowest rates in later years of occupation of more optimal sites (c. 55 – 70 trees / beaver / calendar year). Preferences were generally for willow and aspen trees, with conifers almost entirely avoided, and smaller trees preferred over larger ones. Proximity of trees to waterbodies was also an important factor, with nearer trees favoured, and generally most felling occurred within 50 m of water. Such behaviour followed the principles of optimal central place foraging. These preferences were less predictable however when intense construction activity was undertaken, with larger trees preferred and generic preferences for deciduous trees apparently invalid. In such cases, close proximity to the construction site was of prime importance. Increased cover of herbaceous plant species was observed in beaver-created canopy gaps in riparian woodland, whilst macrophyte diversity within waterbodies increased slightly in areas of herbaceous grazing. The diversity of terrestrial ground invertebrates was highest in areas of heavy tree-felling, and invertebrate richness and abundance was greatest in areas of herbaceous grazing under an intact tree-canopy. Furthermore, the abundance, diversity and richness of macroinvertebrate communities were increased by beaver-generated woody debris in ponds and streams. Overall, 30% of all macroinvertebrate species collected were found only in beaver-affected areas, due to the refugia and food supply provided by beaver dams, caches and lodges, as well as hydrological effects of these structures. These results are discussed with reference to future plans to return the beaver to Scotland. The habitat usage and modification of riparian ecosystems in northern Britain is likely to be similar to that found in this study, and the results are believed to be relevant, applicable and transferable to many areas of Scotland.
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An historical account of the social and ecological causes of Capercaillie Tetrao urogallus extinction and reintroduction in ScotlandStevenson, Gilbert Buchanan January 2007 (has links)
The capercaillie is the largest member of the grouse family extant in Scotland. This species is reported to have become extinct during the 1700s. It is also reported to have been reintroduced to Scotland from Sweden during the 1800s. There have been many assertions made about the underlying causes of the decline of the species; however the specific causal factors remain unknown. The reintroduction of the capercaillie to Scotland in the 1800s is the only successful reintroduction of a grouse species ever to have occurred in the world. The specific factors behind the success of the reintroduction also remain unknown. This thesis examines the extent to which a selection of historical documentary evidence can help to establish both the causes of the 18th century decline of the capercaillie in Scotland and the successes of the 19th century reintroduction. The methodology of this thesis incorporates facets from the fields of both environmental science and history. The methodology includes three steps. The first step involves the selection of a series of potential critical factors that may have been responsible for the decline of the species in the 1700s; these critical factors were selected from the present day understanding of the ecology and the behaviour of the capercaillie. The second step of the methodology includes the surveying of a series of historical documentary sources. From these surveys historical observations of the species were gathered. The historical documentary sources selected for examination in this thesis include what are referred to here as ‘primary historical source material’ and ‘secondary historical source material’. The majority of the primary historical source material was gathered from the hand written manuscripts of the Breadalbane estate, held at the National Archives of Scotland (NAS) and the Atholl estate held at the Blair Castle Charter Room in Blair Atholl. Other select primary historical source material consulted to a lesser extent, due to time constraints, includes the Forfeited Estates (1745) Inventory and the Baron Court Records for Strathspey and Urquhart (1617–1683) from the Grant estate muniments; both held at the NAS. The secondary historical source material was gathered from published and edited literary collections that include historical accounts of the species. The third and final step of the methodology involves the synthesis of both the historical and environmental information in order to establish to what extent the causes of both the decline of the species in the 1700s and success of its reintroduction in the 1800s can be realised. The findings from this thesis assert that the capercaillie was resident in Scotland from, at least, the end of the Medieval. Moving forward from the Middle Ages this thesis presents observations of the capercaillie throughout the historical period. These observations of the capercaillie appear in many different historical accounts. In some instances these observations are fleeting and do not form the main subject of the particular document in question. In other instances accounts of the species are much more detailed and include references to the ecology and behaviour of the bird. The level of detail included in an observation aside, the frequency with which the species is referred to in the sample of historical documents suggests that sections of the Scottish human population were familiar with the species, in various locations and at various times throughout history. By the 17th century the capercaillie is reported as beginning to become rare in some locations while still remaining comparatively abundant in others. The number of instances where the species is referred to as becoming rare in the historical documents increases between the 17th and the 19th centuries. Despite the reported scarceness of the species in Scotland from around the 17th century onwards, the capercaillie is recorded as persisting in Scotland until around the end of the 1700s. By the early 1800s the number of observations of the species in the secondary historical source material increases. All of the observations in the secondary sources from the early 1800s record the absence of the species from localities and regions of Scotland. No new evidence was found in either the primary or secondary historical source material to challenge the supposition that the capercaillie did become extinct in Scotland after 1785. No detailed quantitative data was available for analysis of the decline of the species. Thus, to investigate the extent to which the historical accounts can help explain the specific causal factors of the reported decline, a synthesis of the environmental and historical data was necessary. The findings of this synthesis suggest that the naturally occurring Scottish population of capercaillie probably persisted in the form of a metapopulation. The two hundred years between the 17th and 19th century most likely saw the extinction of capercaillie sub-populations, before the loss of the overall population of capercaillie around 1785. The sample historical documentary evidence alludes to this pattern of local and/or regional extinction of sub-populations. The cause or causes of the extinction of these sub-populations has focussed on five limiting or critical factors known to affect the species today. These five factors are climate change, particularly weather effects associated with the Little Ice Age, habitat loss and deterioration, disturbance, human hunting and predation by species other than humans also contributed to the species’ extinction. The extent to which these critical factors affected each sub-population would have varied between regions of Scotland occupied by the capercaillie in history. This thesis proposes that there was no single or combination of specific critical factors that were ultimately responsible for the decline of the capercaillie in Scotland during the 1700s. In some areas the capercaillie sub-populations would have most likely died out as a result of habitat loss and deterioration and climate change. Whereas in others predation and inbreeding may have been the critical factors responsible for the species’ demise. More detailed information referring to the capercaillie was found in the historical documentary source material for the period post-extinction (i.e. 1800 onwards). Contrary to popular understanding numerous attempts to reintroduce the capercaillie to Scotland were carried out before the Marquis of Breadalbane’s successful programme in 1837. The historical documentary evidence reports early attempts to reintroduce the species to locations such as the Isle of Arran in 1807, on the Duke of Atholl’s estate in 1822 and on the Earl of Mar’s estate in 1824. None of these reintroduction programmes are reported to have been successful in establishing a ‘wild’ population. However, in some instances the captive rearing programmes initiated did bear some fruit and captive reared birds were sent from Dunkeld by the Duke of Atholl to Kenmore and were used in Breadalbane’s successful reintroduction in 1837. The historical documents report two causes for the failure of these early reintroduction attempts. The first is the sudden death of captive birds, most likely as a result of choking due to stress as observed in recent rearing programmes (i.e. Moss 1986). The reintroduced Arran population is reported to have become extinct in this fashion. The second reported cause of failure is predation by species other than man. For example the entire population of birds brought to Scotland by the Earl of Mar were predated when released on his estate. This thesis offers two critical factors as explanations for the remarkable success of the capercaillie’s reintroduction to Scotland in the 19th century. The first is the method by which the reintroduction was carried out; specifically, the re-establishment of a series of capercaillie sub-populations in different regions of Scotland.
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The management of free-ranging lions on enclosed protected areas.Kettles, Ross. January 2007 (has links)
This Research investigates the potential impacts that free-ranging lions have
within a small (<100 000 hectare), enclosed protected area, and it also
investigates the subsequent challenges to the managers of areas such as
these. A comprehensive literature review reveals that the smaller the
protected area, the more intensively it needs to be managed via active
adaptive management, because perimeter fences do not allow for immigration
and emigration. The consequences of this are over-population; inbreeding
depression; the decline of prey and other predator species; conflict with
neighbouring communities as a result of break-outs; and, in some cases, the
spreading of intra- and interspecies disease. Lions are very proficient breeders
and, in all cases investigated, reserves exceeded their local carrying capacity
within a relatively short period of time.
A range of management interventions can potentially achieve short- and/or
long-term reserve objectives. These interventions include relocation,
contraception, hunting and artificial takeovers. These interventions are
described in terms of the preparation required, the biological consequences
and the sociological influences. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
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