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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Effects of prescribed fire and selective herbicide (Imazapyr) on biodiversity in intensively managed pine stands of Mississippi

Iglay, Raymond Bruce 10 December 2010 (has links)
Prescribed fire and imazapyr are two silviculture tools used to control hardwood midstory competition in intensively managed, mid-rotation pine (Pinus spp.) stands but also may support conservation of biodiversity in the southeastern United States. Therefore, I investigated select measures of biodiversity response, small mammals, reptiles, amphibians, carabid beetles, songbirds, and vegetation communities, to fire and imazapyr treatments in intensively managed, mid-rotation pine stands of east-central Mississippi. I used a randomized complete block design of 6 stands (blocks) with 4, 10- ha treatment plots assigned randomly a treatment of burn only, herbicide only, burn + herbicide, or control. I applied dormant season prescribed fires every 3 years beginning in January 2000 and a one-time application of imazapyr in September 1999 using 877 ml/ha (12.0 liquid oz./ac; Arsenal®, BASF 2006). I sampled avifauna, herpetofauna, small mammal, and carabid beetle communities using appropriate sampling techniques for attaining species-specific relative abundance. I also measured vegetation structure and biomass. Vegetation and bird communities exhibited significant responses to treatments. Imazapyr had the greatest initial impact on communities followed by a long-term effect of repeated prescribed fires on a 3 year fire-return interval. Combining fire and imazapyr perpetuated high-quality browse for white-tailed deer (Odocoileus virginianus), plant species richness, high-priority bird species relative abundances, and diversity of landscape-level vegetation structure and biomass by creating a two-tier vegetation structure (pine canopy and herbaceous understory). Independent treatments also were more effective management approaches to sustain biodiversity than controls by maintaining or increasing overall species richness specifically soon after treatment application. Most responses of other wildlife communities were time-limited suggesting the possibility of greater effects of factors other than treatments such as long-term disturbance regimes (e.g., forest management practices, climate trends), proximity of treatment plots to wetlands, and landscape-level population dynamics including characteristics within and among stands. Combined and independent applications of these treatments will support biodiversity conservation, sustainable forestry objectives, and concomitant timber management goals. Long-term conservation of biodiversity within an intensive timber management matrix also may benefit from future investigations of multiple-herbicide tank mixtures, population dynamics of indicator species, and landscape-level biodiversity responses across multiple strata.
42

PUBLIC PERCEPTIONS AND VALUATION OF WILDLIFE IN THE U.S.

Nicholas A Lancaster (7042940) 13 June 2023 (has links)
<p>Chapter 1: Currently there is no hunting or trapping season on bobcats in Indiana. While a season is being considered by wildlife administrators, there is no basis for establishing a price or understanding potential demand for this species. We use contingent valuation to estimate furbearer hunter and trapper willingness-to-pay (WTP) for a hypothetical bobcat harvest permit in Indiana, USA. Using a mail survey of 2000 randomly selected Indiana registered hunters and trappers, we presented respondents with a description of a hypothetical harvest season, including season dates, equipment restrictions, check-in procedures, counties open for the legal harvest, bag limit (the number of animals that can be legally harvested per individual), and statewide quota (the number of animals that can be legally harvested in aggregate). Following the description, respondents were asked a single-bounded dichotomous choice question about purchasing the proposed permit. By applying the Turnbull estimation method to our collected data, we estimate mean WTP of $21.73 for the proposed permit. Our estimates are sensitive to scope effects, which may be linked to perceived congestion: if hunters believe the bag limit may not be filled, WTP may actually decrease with the bag limit due to perceived congestion, necessitating the simultaneous examination of the bag limit and statewide quota.</p> <p><br></p> <p>Chapter 2: One Health initiatives employed by the Centers for Disease Control and Prevention place emphasis on the interconnectedness of animals, people, plants, and the environment. As new disease threats emerge, the interactions of humans and animals with their environments becomes increasingly important. Deer represent a large, prolific, and suitable host for several diseases that are potentially threatening in the One Health context. Previous works have studied deer-related diseases, such as Bovine tuberculosis and Lyme Disease, and examined risks of transmission in households of varying compositions, such as with and without pets or children. However, research quantifying public perceptions of deer and their role(s) in modern society is lacking. Our research applies social media listening to study perceptions of deer among the general U.S. population through volume (number of mentions) and assessment of tone, in terms of positivity versus negativity (analyzed as online media net sentiment). We study media about five prominent deer-related diseases from January 2018 through December 2021 and demonstrate that while aggregate mentions of the deer diseases we study compose a small proportion of total mentions for deer, net sentiment surrounding outbreaks reflects the seriousness of the health consequences these present. Additionally, we explain fluctuations in deer-disease mentions and net sentiment through real-world events, and demonstrate seasonality in mentions and net sentiment for some diseases of interest. Better understanding of public perceptions of the roles of wildlife, particularly deer who are generally perceived as non-threatening wildlife, is particularly important in today’s One Health context.</p> <p><br></p> <p>Chapter 3: The presence of deer in shared environments with humans may result in both positive and negative affinity towards deer. While literature shows deer-related damages to humans and their property, literature also suggests that deer are a way for humans to connect with nature. Managing deer populations is vital to balancing the positive and negative impacts of deer. Currently, hunting is the most cost-effective way to manage deer populations. We are interested in how hunting impacts the affinity for deer, in addition to how the COVID-19 pandemic plays a role in the perception of deer. Online media posts were analyzed using a social media listening platform, NetBase, for the time period of January 1, 2018 to December 31, 2021. Volume of mentions and affinity via net sentiment were collected at the state level on a weekly basis, and the national level on a daily basis. We utilize an OLS regression with dummies for deer hunting season and COVID at the state level to determine the impacts of hunting seasons and the pandemic on net sentiment. We find that deer hunting being open negatively impacts net sentiment of deer. We utilize Pearson correlations to study the impact of deer management via OTC deer hunting privilege issuance in relation to affinity for deer. We find that OTC privilege issuance is positively correlated with affinity for deer in some states, but the impact on affinity may diminish over time.</p>
43

Comunidade de joaninhas (Coleoptera: Coccinellidae) e aspectos fitot?cnicos da couve (Brassica oleraceae var. acephala) em cons?rcio com coentro (Coriandrum sativum), sob manejo org?nico. / Community of ladybirds (Coleoptera: Coccinellidae) and cropping aspects of kale (Brassica oleraceae var. acephala) intercropped with coriander (Coriandrum sativum), under organic management.

Resende, Andr? Luis Santos 22 February 2008 (has links)
Made available in DSpace on 2016-04-28T14:58:35Z (GMT). No. of bitstreams: 1 2008- Andre Luis Santos Resende01.pdf: 7392122 bytes, checksum: fd01e5b7d3b70d5a684bf2fec040cc46 (MD5) Previous issue date: 2008-02-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The agroecological approaches of vegetable organic production presumed the design of more diversified production units over time and space, where the intercropped systems are included. One of these approaches is that the persistence, the abundance and the diversity of natural enemies that act in the insect-pest biological control are stimulated. In Brazil, despite of informal reports, such as personal communication, little has been recorded about the effects of intercropped systems in populations of insect pests and natural enemies. In this context, the present study has as objectives to determine the diversity and the community structure of the ladybirds (Coleoptera: Coccinellidae) associated with aphids in kale cultivated intercropped with coriander, and to evaluate the potential of coriander to provide the vital resources for survivor and reproduction of ladybirds, as well as evaluate the crop performance of this intercropped system, in agroecologically-based organic production system. The study was conducted in two consecutive years (2006 and 2007) in the experimental farm of integrated crop-livestock production called of Sistema Integrado de Produ??o Agroecol?gica (SIPA) or Fazendinha Agroecol?gica km 47, localized in the municipality of Seropedica, Rio de Janeiro, Brazil, where the experiments were carried out and involved the intercropped system of kale (Brassica oleraceae var. acephala D.C.) with coriander (Coriandrum sativum L.) in relation to kale in the monocrop system, in order to determine the diversity of ladybirds by collection of specimens through removal sampling and yellow sticky cards, as well as characterize the structure of their community by the faunistic analysis. The performance of intercropped system was also evaluated, determining the crop parameters of associated crops. A total of 25 ladybird species are present in the SIPA, but Hyperaspis (Hyperaspis) festiva Mulsant, Scymnus (Pullus) sp.3, Cycloneda sanguinea (L.) and Eriopis connexa Germar were more frequent species. There was no infestation by aphids in kale intercropped with coriander, which was used by the ladybirds as food site (resource of pollen, nectar and alternatives preys), oviposition site, refuge for larvae, pupae and adults, and mating site. As for the cropping parameters, the Land Equivalent Ratio (LER) for the intercropped system of kale with coriander, taking into account the fresh mass yield, were superior in 92% (coriander harvested with 55 days after the sowing) and 85% (coriander allowed for flowering) in relation to monocrop system. The intercropped system of kale with coriander in the arrangement of one row of kale and four paralleled rows of coriander, harvesting the two central rows at 55 days after sowing and allowed the two rows in the border of the seedbed for flowering, do not cause increases of kale yield, but was effective in respect to land effective use and as strategy of ladybirds conservation in diversified production systems. / As abordagens agroecol?gicas de produ??o org?nica vegetal pressup?em o desenho das unidades de produ??o mais diversificado, no tempo e no espa?o, onde se inclui os cons?rcios de culturas, tamb?m conhecidos como policultivos. Um dos princ?pios dessa abordagem ? que atrav?s da diversifica??o dos cultivos, estimula-se a persist?ncia, a abund?ncia e a diversidade de inimigos naturais que atuam no controle biol?gico de insetos-pragas. No Brasil, apesar dos relatos informais, do tipo comunica??o pessoal, pouco tem sido registrado a respeito dos efeitos dos policultivos nas popula??es de insetos-pragas e inimigos naturais. Nesse contexto, o presente estudo teve por objetivos determinar a diversidade e a estrutura da comunidade de joaninhas predadoras (Coleoptera: Coccinellidae) associados a pulg?es em couve, cultivada em cons?rcio com coentro, al?m de avaliar o potencial do coentro como provedor de recursos vitais para sobreviv?ncia e reprodu??o das joaninhas, assim como o desempenho fitot?cnico desse cons?rcio, em sistema de produ??o org?nica conduzido em bases agroecol?gicas. O estudo foi realizado em dois anos consecutivos (2006 e 2007) na unidade experimental de produ??o integrada lavoura-pecu?ria denominada de Sistema Integrado de Produ??o Agroecol?gica (SIPA) ou Fazendinha Agroecol?gica km 47, localizada em Serop?dica (RJ), realizando experimentos que envolveram o cons?rcio couve (Brassica oleraceae var. acephala D.C.) com coentro (Coriandrum sativum L.) em compara??o com o monocultivo de couve, para determinar a diversidade de joaninhas por meio da coleta de indiv?duos atrav?s amostragens por remo??o e placas amarelas adesivas, bem como caracterizar a estrutura de sua comunidade por meio da an?lise faun?stica. O desempenho do cons?rcio foi tamb?m avaliado, determindo os par?metros fitot?cnicos das culturas associadas. Um total de 25 esp?cies de joaninhas est? presente no SIPA, mas Hyperaspis (Hyperaspis) festiva Mulsant, Scymnus (Pullus) sp.3, Cycloneda sanguinea (L.) e Eriopis connexa Germar foram as esp?cies mais frequentes na comunidade. N?o houve infesta??o por pulg?es na couve consorciada com coentro, o qual foi usado pelas joaninhas como s?tio de alimenta??o (fonte de p?len, n?ctar e presas alternativas), s?tio de oviposi??o, abrigo para larvas, pupas e adultos, al?m de s?tio de acasalamento. Quanto aos par?metros fitot?cnicos, o ?ndice de equival?ncia de ?rea (IEA) para os cons?rcios couve e coentro, considerando as produtividades de massa fresca, foram superiores em 92% (coentro colhido aos 55 dias ap?s a semeadura) e 85% (coentro deixado para florescer) em rela??o aos cultivos solteiros. O cons?rcio couve-coentro no arranjo de uma linha central de couve e quatro linhas paralelas de coentro, colhendo-se as duas centrais aos 55 dias ap?s a semeadura e deixando as duas linhas na borda do canteiro para florescer, n?o causa aumentos de produtividade da couve, mas mostra-se eficiente em termo do uso eficiente da terra e como estrat?gia de conserva??o de joaninhas nos sistemas de produ??o diversificados.
44

L’utilisation des rizières par les canards hivernants : vers une gestion des rizières en interculture favorable aux canards et aux agriculteurs / The use of rice fields by wintering ducks : towards mutual benefits for ducks and farmers

Pernollet, Claire 24 February 2016 (has links)
Les rizières constituent des habitats favorables pour les oiseaux d’eau, en particulier en tant que halte migratoire, zone de reproduction ou site d’alimentation hivernal. Dans ce dernier cas, la disponibilité des ressources alimentaires (grains de riz non ramassés, graines d’adventices ou invertébrés) semble être fortement influencée par les pratiques culturales post-récolte. Ce projet vise à tester des pratiques post-récolte alternatives au brûlage-labour traditionnellement mis en place en Camargue afin de mesurer les conséquences en termes de disponibilité de nourriture et de fréquentation des parcelles par les canards hivernants. Différents traitements post-récolte (inondation, brûlage, labour, disquage et leurs combinaisons) ont été testés. Nous avons réalisé un suivi de la quantité de graines (riz, adventices) disponibles au cours du temps, depuis la récolte en Septembre-Octobre jusqu'en Mars ainsi qu’un suivi de l'usage des parcelles par les canards pendant la journée et pendant la nuit. En parallèle, nous avons étudié les bénéfices agronomiques potentiels de certaines pratiques en interculure et nous avons cherché à identifier une solution mutuellement bénéfique, répondant aux besoins d’habitat d'hivernage des canards et à ceux des riziculteurs, le tout à moindre coût. / Rice fields provide foraging habitat to waterfowl during migration, breeding and wintering seasons. In the latter case, food availability (waste rice, weed seeds or invertebrates) seems to be strongly influenced by post-harvest agricultural practices. This project aims at testing alternative post-harvest practices to the traditional burning-mowing in the Camargue in order to assess their consequences in terms of food availability and field use by wintering ducks. Different post-harvest treatments (flooding, burning, mowing, disking and their combinations) were conducted. The amount of seeds (rice + weeds) available through time was assessed, from harvest in Sept-Oct until March, and duck use of these fields during the day and during the night was simultaneously monitored. In parallel, we studied potential agronomic benefit of specific post harvest practices and we searched a mutually beneficial solution that provides needed wintering ducks habitat and is acceptable to rice farmers with limited costs.
45

Effects of translocation on kokako (Callaeas cinerea wilsoni) song and its application to management : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand

Van Herpt, Sarah Michelle January 2009 (has links)
This thesis fills a research gap in our knowledge of kokako song by looking at how song evolves in multi-dialect areas. Kokako only exist in small remnant populations separated by large tracts of unsuitable land. Kokako are very poor flyers, only able to fly for approximately 100 metres at a time. In order to prevent inbreeding and a loss of genetic diversity in the remaining kokako populations, managers are carrying out translocations to establish new populations, maintain gene flow and prevent inbreeding. However, these translocations have the potential to be unsuccessful because kokako exhibit macrogeographic variation in their dialects, and tend not to breed with individuals who do not share the same dialect as them. If the purpose of the translocation is to enhance genetic diversity by having kokako from different areas breed then song is an important factor that must be dealt with. Song is extremely important to kokako for a number of reasons. Chiefly, it is hypothesised that song is their primary means of territory defence. A kokako gains all its resources from its territory, so it is imperative that they successfully defend it. Their duet song functions in territory defence, but also acts to form and maintain pair bonds. In order to try and address the problem that song causes in translocations I studied if and how song evolves in a multiple dialect area. I conducted research at Pukaha Mount Bruce, where there is a population of kokako originating from two different source populations, and thus two different dialects, Northern Mapara and Mangatutu. I looked at the Northern Mapara dialect, and recorded kokako belonging to three groups; kokako currently living in the source population, kokako that were translocated to Pukaha and kokako that were born at Pukaha. In order to determine how the song may be changing I looked at element repertoires, the levels of sharing between groups, the number of unique elements in repertoires and the syntactical and temporal characteristics of phrases. This study shows that translocation into multiple dialect areas can affect kokako song. Translocation did not affect the size of the kokako repertoire, but it seemed to affect the amount of sharing within and between different groups of kokako. Currently the level of sharing within the groups at Pukaha is lower than the level of sharing within the source Mapara population, indicating that the song may be diverging. There also seem to be more unique elements found at Pukaha, which in part explains the lack of sharing. There appears to be microgeographic variation at Pukaha, with birds clustered around the second (Mangatutu) dialect sharing less with the source population than do those kokako whose territories are lower down in the reserve. The phrases which are used are also evolving, with only one phrase truly shared among all groups. There are other phrases which show additions or deletions of elements, and so are evolving. The main change found in the phrases is the timing between elements, with six out of seven phrases examined showing changes. These results have repercussions for future kokako translocations, and the future of the Pukaha kokako. A low amount of phrase and element type sharing combined with changes of intra-phrase timing could lead to the Pukaha kokako’s inability to successfully defend their territories. This research shows how kokako song can give conservation managers information on the status of their populations in regards to interbreeding and raises questions which can be answered by further research, both at Pukaha and in other mixeddialect kokako populations.
46

Effects of translocation on kokako (Callaeas cinerea wilsoni) song and its application to management : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand

Van Herpt, Sarah Michelle January 2009 (has links)
This thesis fills a research gap in our knowledge of kokako song by looking at how song evolves in multi-dialect areas. Kokako only exist in small remnant populations separated by large tracts of unsuitable land. Kokako are very poor flyers, only able to fly for approximately 100 metres at a time. In order to prevent inbreeding and a loss of genetic diversity in the remaining kokako populations, managers are carrying out translocations to establish new populations, maintain gene flow and prevent inbreeding. However, these translocations have the potential to be unsuccessful because kokako exhibit macrogeographic variation in their dialects, and tend not to breed with individuals who do not share the same dialect as them. If the purpose of the translocation is to enhance genetic diversity by having kokako from different areas breed then song is an important factor that must be dealt with. Song is extremely important to kokako for a number of reasons. Chiefly, it is hypothesised that song is their primary means of territory defence. A kokako gains all its resources from its territory, so it is imperative that they successfully defend it. Their duet song functions in territory defence, but also acts to form and maintain pair bonds. In order to try and address the problem that song causes in translocations I studied if and how song evolves in a multiple dialect area. I conducted research at Pukaha Mount Bruce, where there is a population of kokako originating from two different source populations, and thus two different dialects, Northern Mapara and Mangatutu. I looked at the Northern Mapara dialect, and recorded kokako belonging to three groups; kokako currently living in the source population, kokako that were translocated to Pukaha and kokako that were born at Pukaha. In order to determine how the song may be changing I looked at element repertoires, the levels of sharing between groups, the number of unique elements in repertoires and the syntactical and temporal characteristics of phrases. This study shows that translocation into multiple dialect areas can affect kokako song. Translocation did not affect the size of the kokako repertoire, but it seemed to affect the amount of sharing within and between different groups of kokako. Currently the level of sharing within the groups at Pukaha is lower than the level of sharing within the source Mapara population, indicating that the song may be diverging. There also seem to be more unique elements found at Pukaha, which in part explains the lack of sharing. There appears to be microgeographic variation at Pukaha, with birds clustered around the second (Mangatutu) dialect sharing less with the source population than do those kokako whose territories are lower down in the reserve. The phrases which are used are also evolving, with only one phrase truly shared among all groups. There are other phrases which show additions or deletions of elements, and so are evolving. The main change found in the phrases is the timing between elements, with six out of seven phrases examined showing changes. These results have repercussions for future kokako translocations, and the future of the Pukaha kokako. A low amount of phrase and element type sharing combined with changes of intra-phrase timing could lead to the Pukaha kokako’s inability to successfully defend their territories. This research shows how kokako song can give conservation managers information on the status of their populations in regards to interbreeding and raises questions which can be answered by further research, both at Pukaha and in other mixeddialect kokako populations.
47

Spatial pattern in macroinvertebrate communities in headwater streams of New Zealand and a multivariate river classification system : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Ecology at Massey University, Palmerston North, New Zealand

Chakraborty, Manas January 2008 (has links)
Macroinvertebrate data collected from 120 headwater streams in New Zealand were used to test the ability of the Freshwater Environments of New Zealand River Classification (FWENZ) to explain spatial variation in unimpacted stream invertebrate communities. FWENZ is a GIS based multivariate river environment classification of the sections of national river network. The classification performance of the FWENZ was examined to determine the optimum classification level which could be used for the purpose of conservation and biomonitoring of New Zealand rivers and streams. The classification performance of the FWENZ was also compared to those of two other river classification systems, the ecoregions and the River Environment Classification (REC). Results of the analysis of similarity (ANOSIM) test showed that discrimination of the study sites based on interclass differences in macroinvertebrate community composition was optimal at FWENZ 100 class level which classifies the New Zealand rivers and streams into 100 different groups. The FWENZ 100 class level distinguished the biological variation of the study sites at a finer spatial scale than the REC Geology level. Although performance of the ecoregions classification was stronger than both the river environmental classifications, the REC and the FWENZ, but it was unable to explain the variation in local assemblage structures. Multivariate analyses of the macroinvertebrate abundance data and the associated environmental variables at three different spatial scales (upstream catchment, segment, and reach) were used to identify environmental predictors of assemblage patterns. Catchmentscale measures of climatic, topographic and landcover factors were more strongly correlated with macroinvertebrate community structures than segment scale measures, whereas reachscale measures of instream physicochemical factors and riparian characteristics had the least association with assemblage patterns. Despite the strong influences of cathment-scale factors on macroinvertebrate communities, local factors like water temperature, stream velocity, reach elevation, percent canopy cover and percent moss cover were also involved in explaining the within-region variation in assemblage patterns, which indicates the importance of considering regional as well as local factors as surrogates of stream invertebrate communities to provide a base for stream bioassessment programmes at multiple scales.
48

The impact of isolation from mammalian predators on the anti-predator behaviours of the North Island robin (Petroica longipes) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Auckland, New Zealand

Whitwell, Sarah Margaret January 2009 (has links)
Conservation in New Zealand has begun to focus heavily on the restoration of degraded mainland ecosystems and the reintroduction of native species that have become locally extinct. In many cases the individuals that are selected for reintroduction are harvested from ‘mammal-free’ offshore islands. This thesis examines the effects of isolation from mammalian predators on the predator avoidance behaviours and predator recognition abilities of New Zealand birds using the North Island robin as a model. It also investigates whether any effects of isolation from mammalian predators has a lasting impact on mainland populations founded by individuals from offshore islands. Nest site selection behaviours were compared across three populations that are exposed to different suites of predators and have differing translocation histories; Benneydale, Tiritiri Matangi and Wenderholm. Point height intercept and point-centred quarter surveys were used to compare habitat availability between the sites and to compare nest sites with the available habitat. Eight nest characteristic variables were also compared across the three sites using a principle component analysis. Benneydale nests were located higher in the trees and were more concealed than nests at the other two sites. Nests on Tiritiri Matangi were supported by large numbers of thin branches and were located toward the periphery of the nest tree. Unfortunately these differences are very difficult to interpret due to a high degree of variation in the habitat types present at the three sites. The anti-predator behaviours initiated in response to a model stoat, model morepork and control were used to test the ability of nesting robins to recognise the threat that each of these treatments might pose to nest success. Behavioural variables were compared between Benneydale, Tiritiri Matangi and Wenderholm using a response intensity scoring system and a principle component analysis. The results indicated that isolation from mammalian predators on Tiritiri Matangi has suppressed the ability of robins on the island to recognise the predatory threat posed by a stoat. They also suggest that the intense mammal control carried out at Wenderholm may have inhibited the ability of local robins to produce strong anti-predator responses when faced with a stoat.
49

Effects of translocation on kokako (Callaeas cinerea wilsoni) song and its application to management : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand

Van Herpt, Sarah Michelle January 2009 (has links)
This thesis fills a research gap in our knowledge of kokako song by looking at how song evolves in multi-dialect areas. Kokako only exist in small remnant populations separated by large tracts of unsuitable land. Kokako are very poor flyers, only able to fly for approximately 100 metres at a time. In order to prevent inbreeding and a loss of genetic diversity in the remaining kokako populations, managers are carrying out translocations to establish new populations, maintain gene flow and prevent inbreeding. However, these translocations have the potential to be unsuccessful because kokako exhibit macrogeographic variation in their dialects, and tend not to breed with individuals who do not share the same dialect as them. If the purpose of the translocation is to enhance genetic diversity by having kokako from different areas breed then song is an important factor that must be dealt with. Song is extremely important to kokako for a number of reasons. Chiefly, it is hypothesised that song is their primary means of territory defence. A kokako gains all its resources from its territory, so it is imperative that they successfully defend it. Their duet song functions in territory defence, but also acts to form and maintain pair bonds. In order to try and address the problem that song causes in translocations I studied if and how song evolves in a multiple dialect area. I conducted research at Pukaha Mount Bruce, where there is a population of kokako originating from two different source populations, and thus two different dialects, Northern Mapara and Mangatutu. I looked at the Northern Mapara dialect, and recorded kokako belonging to three groups; kokako currently living in the source population, kokako that were translocated to Pukaha and kokako that were born at Pukaha. In order to determine how the song may be changing I looked at element repertoires, the levels of sharing between groups, the number of unique elements in repertoires and the syntactical and temporal characteristics of phrases. This study shows that translocation into multiple dialect areas can affect kokako song. Translocation did not affect the size of the kokako repertoire, but it seemed to affect the amount of sharing within and between different groups of kokako. Currently the level of sharing within the groups at Pukaha is lower than the level of sharing within the source Mapara population, indicating that the song may be diverging. There also seem to be more unique elements found at Pukaha, which in part explains the lack of sharing. There appears to be microgeographic variation at Pukaha, with birds clustered around the second (Mangatutu) dialect sharing less with the source population than do those kokako whose territories are lower down in the reserve. The phrases which are used are also evolving, with only one phrase truly shared among all groups. There are other phrases which show additions or deletions of elements, and so are evolving. The main change found in the phrases is the timing between elements, with six out of seven phrases examined showing changes. These results have repercussions for future kokako translocations, and the future of the Pukaha kokako. A low amount of phrase and element type sharing combined with changes of intra-phrase timing could lead to the Pukaha kokako’s inability to successfully defend their territories. This research shows how kokako song can give conservation managers information on the status of their populations in regards to interbreeding and raises questions which can be answered by further research, both at Pukaha and in other mixeddialect kokako populations.
50

Effects of translocation on kokako (Callaeas cinerea wilsoni) song and its application to management : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand

Van Herpt, Sarah Michelle January 2009 (has links)
This thesis fills a research gap in our knowledge of kokako song by looking at how song evolves in multi-dialect areas. Kokako only exist in small remnant populations separated by large tracts of unsuitable land. Kokako are very poor flyers, only able to fly for approximately 100 metres at a time. In order to prevent inbreeding and a loss of genetic diversity in the remaining kokako populations, managers are carrying out translocations to establish new populations, maintain gene flow and prevent inbreeding. However, these translocations have the potential to be unsuccessful because kokako exhibit macrogeographic variation in their dialects, and tend not to breed with individuals who do not share the same dialect as them. If the purpose of the translocation is to enhance genetic diversity by having kokako from different areas breed then song is an important factor that must be dealt with. Song is extremely important to kokako for a number of reasons. Chiefly, it is hypothesised that song is their primary means of territory defence. A kokako gains all its resources from its territory, so it is imperative that they successfully defend it. Their duet song functions in territory defence, but also acts to form and maintain pair bonds. In order to try and address the problem that song causes in translocations I studied if and how song evolves in a multiple dialect area. I conducted research at Pukaha Mount Bruce, where there is a population of kokako originating from two different source populations, and thus two different dialects, Northern Mapara and Mangatutu. I looked at the Northern Mapara dialect, and recorded kokako belonging to three groups; kokako currently living in the source population, kokako that were translocated to Pukaha and kokako that were born at Pukaha. In order to determine how the song may be changing I looked at element repertoires, the levels of sharing between groups, the number of unique elements in repertoires and the syntactical and temporal characteristics of phrases. This study shows that translocation into multiple dialect areas can affect kokako song. Translocation did not affect the size of the kokako repertoire, but it seemed to affect the amount of sharing within and between different groups of kokako. Currently the level of sharing within the groups at Pukaha is lower than the level of sharing within the source Mapara population, indicating that the song may be diverging. There also seem to be more unique elements found at Pukaha, which in part explains the lack of sharing. There appears to be microgeographic variation at Pukaha, with birds clustered around the second (Mangatutu) dialect sharing less with the source population than do those kokako whose territories are lower down in the reserve. The phrases which are used are also evolving, with only one phrase truly shared among all groups. There are other phrases which show additions or deletions of elements, and so are evolving. The main change found in the phrases is the timing between elements, with six out of seven phrases examined showing changes. These results have repercussions for future kokako translocations, and the future of the Pukaha kokako. A low amount of phrase and element type sharing combined with changes of intra-phrase timing could lead to the Pukaha kokako’s inability to successfully defend their territories. This research shows how kokako song can give conservation managers information on the status of their populations in regards to interbreeding and raises questions which can be answered by further research, both at Pukaha and in other mixeddialect kokako populations.

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