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Enhancing ecosystem services in vineyards to improve the management of Botrytis cinereaJacometti, Marco Alexander Azon January 2007 (has links)
Organic mulches and cover crops mulched in situ were assessed for their effects on B. cinerea primary inoculum and disease levels in inflorescences at flowering and/or bunches at harvest.
Organic mulches were used to enhance biological degradation of vine debris to reduce levels of B. cinerea primary inoculum the following season. Four mulch types (anaerobically and aerobically fermented marc (grape pressings), inter-row grass clippings and shredded office paper) were applied under ten-year-old Riesling vines in a ten-replicate randomized block design in New Zealand over two consecutive years. Plastic mesh bags, each containing naturally infected vine debris, were placed under vines on bare ground (control) and at the soil-mulch interface, in winter (July) 2003 and 2004. In each year, half the bags were recovered at flowering (December) and the remainder at leaf plucking (February), for assessment of B. cinerea sporulation from the vine debris and debris degradation rate. Bait lamina probes, which measure soil biological activity, were placed in the soil-mulch interface three weeks before each of the two bag-recovery dates in both years and were then removed and assessed at the same times as were the bags. All mulches led to a reduction in B. cinerea sporulation. This reduction was significantly correlated with elevated rates of vine debris decomposition and increased soil biological activity. Over both years, compared with the controls, all treatments gave a 3-20-fold reduction in B. cinerea sporulation, a 1.6-2.6-fold increase in vine debris degradation and in the two marc and the paper treatments, a 1.8-4-fold increase in activity of soil organisms.
The mulches also altered vine characteristics and elevated their resistance to B. cinerea through changes to the soil environment. Functional soil biological activity, as measured by Biolog Ecoplates and bait lamina probes, was increased 2-4 times in the two marc and paper treatments, compared with the control, an effect relating to the elevated soil moisture and reduced temperature fluctuations under these mulches. Soil nutrient levels and the C:N ratios were also affected in these treatments. The mulched paper lowered vine canopy density by up to 1.4 times that of the other treatments, an effect which probably led to elevated light penetration into the canopy and consequent increased canopy temperature, photosynthesis and lowered canopy humidity. These changes to soil and vine characteristics increased grape skin strength by up to 10% in the paper treatment and sugar concentrations by 1.2-1.4 °Brix in the two marc and paper treatments. The severity of B. cinerea infections in the anaerobic marc, aerobic marc and paper treatments were reduced to 12%, 3% and 2.2% of the control, respectively, in field assessments averaged over two consecutive harvests.
Cover crops mulched in situ had similar effects to those of the organic mulches, increasing soil biological activity and reducing B. cinerea primary inoculum and the severity of B. cinerea infection in grapes at harvest (2006). Inter-row phacelia and ryegrass were mulched in winter 2005 and compared with a bare ground control, under 10-year-old Chardonnay vines in a ten-replicate randomized block design. Functional soil biological activity increased by 1.5-4.5 times in the two cover crop treatments compared with the control, an effect possibly related to elevated soil moisture in these treatments. This increase in soil moisture and soil biological activity increased vine debris degradation, reduced B. cinerea primary inoculum on the debris and decreased B. cinerea severity at flowering (December 2005) and harvest (April 2006).
These results show the potential of organic mulches and cover crops mulched in situ to enhance soil ecosystem services and improve the sustainability of viticultural practices.
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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 ZealandVan 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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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 ZealandVan 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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Estimation du potentiel de résistance de Botrytis cinerea à des biofongicidesAjouz, Sakhr 21 December 2009 (has links) (PDF)
La pourriture grise, causée par le champignon Botrytis cinerea, est l'une des principales maladies aériennes fongiques sur diverses cultures d'importance agronomique. La diversité génétique de B. cinerea est très forte et la capacité rapide d'adaptation de ce champignon à une pression sélective est également avérée. Ce champignon est ainsi capable de développer des résistances à une grande variété de composés fongicides de synthèse ou d'origine naturelle. Des méthodes alternatives de lutte ont de ce fait été développées ces dernières années : divers agents de lutte biologique (ALB) présentant différents modes d'actions ont été identifiés et pour certains d'entre eux commercialisés pour contrôler B. cinerea. Cependant la durabilité de la lutte biologique est un domaine encore très peu étudié. La perte d'efficacité d'un ALB pourrait résulter de la préexistence d'isolats moins sensibles de pathogènes dans les populations naturelles et/ou de la capacité de l'agent pathogène à produire, sous une pression de sélection continue exercée par l'ALB, des mutants ayant une sensibilité réduite. L'objectif global de la présente étude est d'évaluer le risque potentiel de perte d'efficacité de la lutte biologique vis-à-vis de B. cinerea. Dans cette étude, les efforts ont été concentrés sur la pyrrolnitrine, un antibiotique produit par divers ALBs, dont certains sont efficaces contre B. cinerea. Les objectifs spécifiques de l'étude étaient (i) d'évaluer la diversité de la sensibilité à la pyrrolnitrine au sein de la population naturelle de B. cinerea, (ii) d'estimer le risque de perte d'efficacité des ALBs produisant la pyrrolnitrine due à la pression de sélection exercée par la pyrrolnitrine et (iii) d'étudier le mécanisme de résistance à la pyrrolnitrine chez B. cinerea. Parmi 204 isolats de B. cinerea, une gamme importante de sensibilité à la pyrrolnitrine a été observée, avec un facteur de résistance de 8,4 entre l'isolat le plus sensible et l'isolat le moins sensible. La production de 20 générations successives pour 4 isolats de B. cinerea, sur des doses croissantes de pyrrolnitrine, a abouti au développement de mutants avec des niveaux élevés de résistance à l'antibiotique, et à une réduction in vitro de la sensibilité à la bactérie productrice de pyrrolnitrine Pseudomonas chlororaphis PhZ24. La comparaison entre les mutants résistants à la pyrrolnitrine et leurs parents sensibles pour la croissance mycélienne, la sporulation et l'agressivité sur plantes a révélé que la résistance à la pyrrolnitrine est associée à un fort coût adaptatif. Des observations cytohistologiques sur tomates ont confirmé que l'isolat sensible à la pyrrolnitrine attaque le pétiole rapidement et envahit la tige, alors que le mutant résistant à la pyrrolnitrine ne s'étend pas au-delà du pétiole. De plus, ce dernier mutant forme un mycélium anormal et des cellules ressemblant à des chlamydospores. Les résultats ont d'autre part révélé que les mutants de B. cinerea résistants à la pyrrolnitrine sont résistants au fongicide iprodione, suggérant ainsi qu'une pression exercée par la pyrrolnitrine sur le champignon conduit à une résistance au fongicide. Réciproquement, la production de générations successives sur iprodione conduit à une résistance à l'antibiotique. Afin d'étudier les déterminants moléculaires de la résistance de B. cinerea à la pyrrolnitrine, le gène histidine kinase Bos1, impliqué entre autres dans la résistance aux fongicides chez B. cinerea a été séquencé chez les souches sensibles et les mutants résistants. La comparaison des séquences a mis en évidence des mutations ponctuelles différentes chez les mutants de B. cinerea obtenus sur la pyrrolnitrine et ceux obtenus sur l'iprodione. De plus, les résistances à la pyrrolnitrine et à l'iprodione ne sont pas systématiquement associées à une mutation ponctuelle dans le gène Bos1. Enfin, aucune modification n'a été détectée dans la taille des allèles de neuf locus microsatellites quelle que soit la pression sélective exercée et quelle que soit le phénotype du mutant produit. Cette étude montre qu'un champignon pathogène des plantes est capable de développer progressivement une moindre sensibilité à un agent de lutte biologique mais que cette moindre sensibilité est associée à une forte perte de fitness
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Epiphytic yeasts isolated from apple leaves to control of gray and blue mold fruit rots of appleFalconi, Cesar E. 14 June 1996 (has links)
Eight phylloplane yeasts were isolated from backyard apple trees in
Corvallis, OR. Yeast isolates were classified to genus or species level. All
isolates were tested in vitro for antagonistic activity against the postharvest
pathogens Botrytis cinerea and Penicillium expansum. Of these isolates,
Aureobasidium pullulans, Sporobolomyces roseus Rhodotorula sp., consistently
reduced mycelial growth of B. cinerea and P. expansum in nutrient yeast
dextrose agar (pH 4.5 or 7.0) incubated for 8 or 30 days at 24 or 1 C, respectively.
These three yeasts also were evaluated for their ability to suppress spore
germination of B. cinerea and P. expansum in a gradient of apple juice
concentrations and to suppress development of gray and blue mold lesions in
inoculated fruits of Golden Delicious apple. Germination of B. cinerea and P.
expansum was reduced significantly (P���0.05) when incubated with the yeast
isolates in 100 or 50% apple juice, but not in 0, 1 or 10% apple juice. S. roseus
and A. pullulans reduced significantly (P���0.05) the size of gray mold lesions in
wounded fruit stored at 5 C and 24 C by 63 to 72 and 81 to 90%, respectively,
when compared to the nontreated control. Size of blue mold lesions in fruit
stored at 5 and 24 C also were reduced significantly (P���0.05) by 66 to 38 and 74
to 63%, respectively, when pre-treated with S. roseus and A. pullulans. In
general, fruit rot suppression by some yeasts isolated in this study was similar in
magnitude to suppression obtained by Cryptococcus laurentii isolate 87-108, a
yeast with commercial potential to suppress postharvest rots of pome fruits.
Pretreatment of apple wounds with washed cells of A. pullulans, S. roseus,
Rhodotorula sp., resulted in disease suppression, but treatment of wounds with cell-free culture supernatant of these isolates did not affect lesion development. Population size of A. pullulans, S. roseus, and C. laurentii increased in apple wounds incubated at 5 or 24 C for up to 25 days, indicating that they colonized the wound site. Data collected in this study support the hypothesis that yeast isolates antagonize fruit pathogens by competing for nutrients in wounds on fruit surfaces. The isolates of A. pullulans and S. roseus show promise for commercial development. / Graduation date: 1997
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Life-history consequenses of host plant choice in the comma butterflySöderlind, Lina January 2012 (has links)
There is much evidence that herbivory is a key innovation for the tremendous success of insect. In this thesis I have investigated different aspects of host plant utilization and phenotypic plasticity using the polyphagous comma butterfly, Polygonia c-album. Even though external conditions affect a phenotypic plastic response, the outcome is often influenced by a genetic background which may differ among populations. In Paper I we suspected the genetic background to seasonal polymorphism to be X-linked. However, results from interspecific hybridization between two populations suggested that diapause response is instead inherited in a mainly autosomally additive fashion, with a possible influence of sexual antagonism on males. In Paper II we showed that female oviposition preference is not a plastic response influenced by larval experience, but has a genetic background coupled to host plant suitability. Further, there is a strong individual correlation between larval host plant acceptance and female host plant specificity (Paper III). We believe this to be a larval feed-back genetically linked to female host specificity: offspring to ‘choosy’ specialist mothers benefit by remaining on the original host while offspring to less discriminating generalist mothers should risk inspecting the surroundings, thus compensating for potential poor female choice. In the larval mid-gut, genes are differentially expressed depending on host plant diet (Paper IV). Therefore, we expected to find fitness consequences of host plant switch. However, although growth rate was affected in a few treatments, larvae were generally surprisingly good at adjusting to new diets (Paper V). To conclude, host plant choice in both female and larval life stage is connected to performance. Combined with increased understanding about the plastic response to diet intake and seasonal polymorphism we have gained further insights into the processes of local adaptations and speciation in the Lepidoptera. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted Manuscript; Paper 5: Manuscript
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BIOLOGY, EPIDEMIOLOGY AND MODELLING OF BOTRYTIS CINEREA PERS.:FR., THE CAUSAL AGENT OF GREY MOULD IN GRAPEVINECILIBERTI, NICOLA 28 January 2015 (has links)
Gli obbiettivi di questa tesi di dottorato erano: i) valutare l’effetto di differenti condizioni ambientali sulla biologia ed epidemiologia di isolati di B. cinerea appartenenti alle sub-popolazioni transposa e vacuma, e ii) sviluppare un nuovo modello previsionale per predire il rischio di muffa grigia nei vigneti tra le fasi fenologiche di sviluppo delle infiorescenze e maturazione dei grappoli.
Gli effetti della temperatura, durata di bagnatura e umidità relativa sulle infezioni di infiorescenze e bacche di Vitis vinifera sono stati valutati con inoculazioni artificiali di isolati di B. cinerea. Gli effetti della temperatura, attività dell’acqua, umidità relativa e composizione delle bacche di uva sulla germinazione dei conidi, crescita miceliale e produzione di conidi sono stati valutati su substrati artificiali. I risultati evidenziano che la capacità di causare infezioni varia con gli isolati indipendentemente dall’appartenenza alle sub-popolazioni transposa o vacuma. Inoltre, le risposte dei differenti isolati al variare delle condizioni ambientali risultano essere simili.
Basandosi sui risultati ottenuti sono state sviluppate equazioni matematiche per spiegare l’effetto dei fattori ambientali sull’incidenza delle infezioni di infiorescenze e bacche, germinazione dei conidi, crescita miceliale e produzione di conidi. Un nuovo modello previsionale è stato sviluppato per predire le infezioni di Botrytis cinerea nei vigneti utilizzando le equazioni sviluppate e seguendo un approccio meccanicistico. Il modello è stato validato per 6 anni (2009-2014) in 13 vigneti localizzati in Italia e Francia. Il nuovo modello risulta essere più completo di quelli proposti finora in letteratura e può essere utilizzato per migliorare le strategie di controllo della muffa grigia nei vigneti. / The aims of this Doctoral work were: i) to investigate the effect of different environmental conditions on biology and epidemiology of B. cinerea strains belonging the two transposon types vacuma and transposa, and ii) develop a new weather-driven mechanistic model in order to predict risk of grey mould in vineyards from early growth of inflorescences to berry ripening.
The effect of temperature, wetness duration and relative humidity on infection of Vitis vinifera inflorescences and berries was investigated by artificial inoculation of B. cinerea strains. The effect of temperature, water activity, relative humidity and grape berry composition on conidia germination, colony growth and conidial production was investigated in agar-medium. The results showed that the ability to cause infection was a strain rather than a transposon genotype attribute. Moreover, the general response to different environmental conditions is similar among different B. cinerea strains.
Based on these data, equations were developed to account the combined effects of environmental factors on infection incidence, conidia germination, colony growth and conidial production. A new previsional model for Botrytis cinerea infections on grapevine was elaborated using the equations developed and following a mechanistic approach. The model was validated over a 6-year period (2009 to 2014) in 13 vineyards located in different grape-growing areas of Italy and France. The model is more complete than the others proposed in literature and represents an improvement to control grey mould in vineyards.
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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 ZealandVan 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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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 ZealandVan 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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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 ZealandVan 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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