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En ny däggdjursart i Sveriges fauna : Etablering av stenmård (Martes foina) i nordöstra Skåne / A new mammal in the Swedish fauna : The establishment of stone marten (Martes foina) in north-eastern ScaniaSvensson, Elin, Wetterberg, Karin January 2021 (has links)
Skogsmård (Martes martes) har länge varit Sveriges enda mårdart men 2018 gjordes det första fyndet av en annan art, stenmård (Martes foina), i nordöstra Skåne. Efter att detta fynd uppmärksammats fick Invasiva Arter på Svenska Jägareförbundet in uppgifter om ytterligare tre fynd från området. Syftet med studien var således att undersöka om stenmård är en etablerad art i nordöstra Skåne samt att undersöka om det finns släktskap mellan de funna individerna. Utifrån tidigare fyra fynd utfördes en fältstudie för att försöka samla in ytterligare fynd av stenmård i nordöstra Skåne, med hjälp av fällfångst. Fältstudien utfördes 1 november 2020–28 februari 2021 vilket motsvarade jakttiden för mård i Skåne. Inga nya fynd av stenmård gjordes under fältstudien, men sju fynd rapporterades in från allmänheten inom studieområdet. Således har totalt elva bekräftade fynd gjorts i Sverige åren 2014–2021, samtliga i nordöstra Skåne. Genetiska analyser utfördes av Naturhistoriska riksmuseet på fyra av kadavren för att undersöka eventuellt släktskap mellan dem, genom att jämföra individernas mitokondrie-DNA. Resultatet visade att de fyra individerna hade samma haplotyp och således härstammar från en gemensam anmoder. Utifrån åldersbestämning och tidpunkt för fällning kunde även bekräftas att de fyra individerna härstammar från minst två kullar och därmed att föryngring skett i området. Vi bedömer stenmård som en etablerad främmande art i nordöstra Skåne, eftersom den inom historisk tid inte ingått i Sveriges fauna och eftersom föryngring bekräftats. Vidare bedömdes att artens potential att klassas som invasiv bör utredas ytterligare utifrån ekologiska, ekosystemrelaterade och ekonomiska aspekter. / Pine marten (Martes martes) was the only marten species in Sweden until 2018 when the first stone marten (Martes foina) was found in the north-east of Scania. When this finding becamepublic, four more records from the area were reported to the Swedish association for hunting and wildlife management. In this study it was investigated if the stone marten is an established species in the north-east of Scania and if there is a genetic relationship between the found individuals. Based on the localization of previous records, a trapping field study was performed to see if further records of stone marten could be made in the north-east of Scania. The field study was executed between 1 November 2020-28 February 2021, which is within the hunting season of martens in the area. The field study did not result in any new records, but in seven new reports from the public within the area. In summary, a total of eleven stone marten records have been made in Sweden 2014-2021, all in the north-east of Scania. The Swedish Museum of Natural History in Stockholm performed genetic analyses offour of the cadavers to investigate their genetic relationship by comparing mitochondrial DNA. Results showed that the four individuals had the same haplotype and therefore originate from one common ancestral female. Based on age determination and time of death it was also confirmed that the four individuals originate from at least two litters and that reproduction has occurred in the area. Since the stone marten historically is not part of theSwedish fauna and since local reproduction was confirmed, it was concluded that the species is an established alien species. It was also concluded that the species potential to be classified as invasive should be further investigated based on ecological, ecosystem related and economical aspects.
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Comprehensive fish health assessment and parasitological investigation of alien and indigenous fishes from the Amatola region, South Africa / Kyle Joseph McHughMcHugh, Kyle Joseph January 2015 (has links)
The conservation of biodiversity and endemism in South Africa’s freshwater aquatic ecosystems is a high priority, particularly in the Cape Floristic Region. However, the perception that South Africa lacks suitable fish species for recreational angling, aquaculture and biological control, led to the widespread introduction and use of alien fish species. As a result, formal stocking programs have seen the introduction of five of the world’s top 100 invasive species into South Africa (Dudgeon et al. 2006). According to Dudgeon et al. (2006) freshwater ecosystems are the most endangered ecosystem in the world. The threats to freshwater biodiversity, according to Dudgeon et al. (2006), can be grouped into five categories that interact with one another: overexploitation, water pollution, flow modifications, destruction of habitat and invasion by exotic species.
This PhD study took place in the Amatola region of the Eastern Cape Province, South Africa. The Amatola region is a rural area with no large-scale mining or industrial developments, only localised settlements. These developments are mainly situated around impoundments, because of the resources such as water and food that they provide. Thus the dams within the Amatola region should theoretically have no major industrial stressors on them. The three impoundments studied were Binfield Park, Sandile and Wriggleswade Dams. Binfield Park Dam is a 260ha impoundment. It impounds the Tyume River and is used by both subsistence anglers from the local communities and occasionally by recreational bass anglers. Sandile Dam is a 146ha impoundment and is the smallest of the three dams in this study. It impounds the Wolf and Keiskamma Rivers. Wriggleswade Dam is a 1000ha impoundment used extensively by recreational bass and carp anglers, and impounds the Kubusi River.
There is a paucity of information regarding the health of the indigenous and alien fish species from the study region, as well as on the parasite diversity of these various fish species. In order to fill the gaps in the information the following hypothesis was proposed. That the necropsy based and histology based fish health assessment can be successfully implemented as tools to assess the effects of heavy metal pollution and alien fish parasites in freshwater fish from selected impoundments in the Amatola region, Eastern Cape Province, South Africa. In order to achieve this
hypothesis the main aim of this study will be to use the necropsy- and histology- based fish health assessment to determine the health status of the fish species in these impoundments as well as to understand the potential threat of water pollution and fish parasites.
Fish were sampled with the aid of gill nets, fyke nets and by angling from each of the three impoundments over three surveys in July 2011, and March and August 2012. Following capture fish were transported to a field laboratory in aerated containers. At the field laboratory the fish were examined and dissected using the methods recommended by Adams et al. (1993) for a necropsy-based fish health assessment. Gills, livers, kidneys and gonads samples were also collected for histological analysis.
Macroscopic and histology-based fish health assessment index was used, as well the analysis of muscle tissue of Micropterus salmoides and surface water and sediment from Binfield Park, Sandile and Wriggleswade Dams. It was shown that, according to the macroscopic fish health assessment index, M. salmoides in Wriggleswade Dam had a higher FHAI score compared to those in Binfield Park and Sandile Dam, there were no significant differences between the FHAI scores. However, the cause of the higher FHAI in the Wriggleswade Dam was because of the external skin damage caused by the presence of the alien parasite Lernaea cyprinacea. The histology-based fish health assessment index, however, showed that M. salmoides from Binfield Park had significantly higher histology Fish Index (IFISH) scores compared to those in Sandile and Wriggleswade Dams. The main contributors to the high IFISH score of Binfield Park were the significantly high Liver Index (IL) and Kidney Index (IK). The increased severity of the alterations observed in the liver and kidney tissue of the Binfield Park M. salmoides samples may have been as a result of the high concentration of mercury found in the muscle tissue of M. salmoides. The water quality and metals detected in the water of Binfield Park, Sandile and Wriggleswade Dams were all below the target water quality guideline values, as well as below those of previous research into the nutrients and presence of metals in these impoundments. The sediment metal analysis showed that the levels of Co, Mn and Ni were above the target guideline levels for Binfield Park, Sandile and Wriggleswade Dams, Cu was above target guidelines levels for Sandile Dam, and uranium was above the target guideline concentrations for Wriggleswade
Dam. Binfield Park Dam had significantly high levels of mercury in the muscle tissue of M. salmoides, while Sandile Dam had significantly high levels of zinc in the muscle tissue of M. salmoides. It was shown that M. salmoides from each of the three impoundments are in a healthy state according to the parameters assessed. However, the presence of heavy metals, particularly mercury, uranium and zinc, do indicate the presence of human activities.
The indigenous parasites of Anguilla mossambica have been well documented including the gastrointestinal nematode Paraquimperia africana, and the stomach nematode Heliconema africanum. Indigenous parasites such as the swimbladder nematode Anguillicola papernai had no effect on the condition factor of infected and uninfected eels. However, the damage caused by the alien parasites were evident, including the first documented effects of the alien gill monogenean Pseudodactylogyrus anguillae on indigenous wild populations of the longin fin eel A. mossambica from the Eastern Cape, South Africa. Histological observations indicated that an alien gill monogenean caused hyperplasia, increase in mucous cells, rupture of pillar cells as well as telangiectasia. This alien parasite has invaded the Keiskamma and Kei River systems in the Eastern Cape, South Africa. According to the macroscopic fish health assessment index, A. mossambica from Binfield Park, Sandile and Wriggleswade Dams are in a healthy state. However, the histology-based health assessment highlighted that the effects on P. anguillae have a severe negative impact on the health of A. mossambica.
Using the macroscopic and histology-based fish health assessment, a comprehensive investigation into the fish health status of Mugil cephalus and Myxus capensis from Binfield Park Dam revealed that human effects and parasites are not the only threats to freshwater fish. Nephrocalcinosis is a non-infectious kidney disease which is characterised by abnormal calcium deposition in the kidneys of humans and some fish species. According to the macroscopic and histology-based fish health assessment, the M. cephalus and M. capensis are not in a healthy condition. The macroscopic and histology-based fish assessment indices are not stressor-specific, and therefore the cause of the poor health state of these two fish species could not be determined. A possible suggestion for the poor health of these two species is the age of the species. Because the two mullet species were stocked
into Binfield Park Dam, Ellender et al. (2012) could successfully age them accurately to ten years of age, which is the upper limit of the life span for these species.
Macroscopic and histology-based fish heath assessments were conducted on Labeo umbratus from Sandile Dam in order to determine the health of this species. Macroscopic and histology-based fish health assessment indicated that its L. umbratus are in a healthy state. The March 2012 survey specimens had a significantly higher macroscopic FHAI score than those from the July 2011 survey. The increased FHAI score was because of parasite infections, as well as discoloured livers and increased total blood plasma protein levels, which are indicators of nutritional state. However, the presence of the anchor worm parasite Lernaea barnimiana in low numbers had no significant impact on the health of L. umbratus.
The effect of the alien anchor worm parasite Lernaea cyprinacea was shown on the transloacted small mouth yellowfish Labeobarbus aeneus. It was also shown that L. aeneus are, according the macroscopic FHAI and the histology-based fish health assessment index, in a healthy state. However, the high scores observed in the macroscopic fish health assessment index were primarily as a result of the presence of the alien parasite L. cyprinacea and its associated affects on the fish host. Because of the significant impact of this alien parasite species on the translocated host species, it can be assumed that this alien parasite species will have a negative effect on the health of indigenous fish species in the Great Kei River.
It is clear from the results presented in this study that the necropsy based and histology based fish health assessment can be successfully implemented as tools to assess the effects of heavy metal pollution and alien fish parasites in freshwater fish from selected impoundments in the Amatola region, Eastern Cape Province, South Africa, thus the original hypothesis of this thesis is accepted.
Based on work done in this research the gaps in research have been identified. Due to the high levels of mercury indentified in the muscle tissue of M. salmoides from Binfield Park Dam. A human health assessment and edibility should be conducted in order to determine if the fish from Binfield Park Dam is safe for human consumption. In order to conserve South Africa’s Freshwater fish biodiversity, country wide surveys of indigenous fish species must be undertaken so that the health and the parasite diversity can be evaluated. / PhD (Zoology), North-West University, Potchefstroom Campus, 2015
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Comprehensive fish health assessment and parasitological investigation of alien and indigenous fishes from the Amatola region, South Africa / Kyle Joseph McHughMcHugh, Kyle Joseph January 2015 (has links)
The conservation of biodiversity and endemism in South Africa’s freshwater aquatic ecosystems is a high priority, particularly in the Cape Floristic Region. However, the perception that South Africa lacks suitable fish species for recreational angling, aquaculture and biological control, led to the widespread introduction and use of alien fish species. As a result, formal stocking programs have seen the introduction of five of the world’s top 100 invasive species into South Africa (Dudgeon et al. 2006). According to Dudgeon et al. (2006) freshwater ecosystems are the most endangered ecosystem in the world. The threats to freshwater biodiversity, according to Dudgeon et al. (2006), can be grouped into five categories that interact with one another: overexploitation, water pollution, flow modifications, destruction of habitat and invasion by exotic species.
This PhD study took place in the Amatola region of the Eastern Cape Province, South Africa. The Amatola region is a rural area with no large-scale mining or industrial developments, only localised settlements. These developments are mainly situated around impoundments, because of the resources such as water and food that they provide. Thus the dams within the Amatola region should theoretically have no major industrial stressors on them. The three impoundments studied were Binfield Park, Sandile and Wriggleswade Dams. Binfield Park Dam is a 260ha impoundment. It impounds the Tyume River and is used by both subsistence anglers from the local communities and occasionally by recreational bass anglers. Sandile Dam is a 146ha impoundment and is the smallest of the three dams in this study. It impounds the Wolf and Keiskamma Rivers. Wriggleswade Dam is a 1000ha impoundment used extensively by recreational bass and carp anglers, and impounds the Kubusi River.
There is a paucity of information regarding the health of the indigenous and alien fish species from the study region, as well as on the parasite diversity of these various fish species. In order to fill the gaps in the information the following hypothesis was proposed. That the necropsy based and histology based fish health assessment can be successfully implemented as tools to assess the effects of heavy metal pollution and alien fish parasites in freshwater fish from selected impoundments in the Amatola region, Eastern Cape Province, South Africa. In order to achieve this
hypothesis the main aim of this study will be to use the necropsy- and histology- based fish health assessment to determine the health status of the fish species in these impoundments as well as to understand the potential threat of water pollution and fish parasites.
Fish were sampled with the aid of gill nets, fyke nets and by angling from each of the three impoundments over three surveys in July 2011, and March and August 2012. Following capture fish were transported to a field laboratory in aerated containers. At the field laboratory the fish were examined and dissected using the methods recommended by Adams et al. (1993) for a necropsy-based fish health assessment. Gills, livers, kidneys and gonads samples were also collected for histological analysis.
Macroscopic and histology-based fish health assessment index was used, as well the analysis of muscle tissue of Micropterus salmoides and surface water and sediment from Binfield Park, Sandile and Wriggleswade Dams. It was shown that, according to the macroscopic fish health assessment index, M. salmoides in Wriggleswade Dam had a higher FHAI score compared to those in Binfield Park and Sandile Dam, there were no significant differences between the FHAI scores. However, the cause of the higher FHAI in the Wriggleswade Dam was because of the external skin damage caused by the presence of the alien parasite Lernaea cyprinacea. The histology-based fish health assessment index, however, showed that M. salmoides from Binfield Park had significantly higher histology Fish Index (IFISH) scores compared to those in Sandile and Wriggleswade Dams. The main contributors to the high IFISH score of Binfield Park were the significantly high Liver Index (IL) and Kidney Index (IK). The increased severity of the alterations observed in the liver and kidney tissue of the Binfield Park M. salmoides samples may have been as a result of the high concentration of mercury found in the muscle tissue of M. salmoides. The water quality and metals detected in the water of Binfield Park, Sandile and Wriggleswade Dams were all below the target water quality guideline values, as well as below those of previous research into the nutrients and presence of metals in these impoundments. The sediment metal analysis showed that the levels of Co, Mn and Ni were above the target guideline levels for Binfield Park, Sandile and Wriggleswade Dams, Cu was above target guidelines levels for Sandile Dam, and uranium was above the target guideline concentrations for Wriggleswade
Dam. Binfield Park Dam had significantly high levels of mercury in the muscle tissue of M. salmoides, while Sandile Dam had significantly high levels of zinc in the muscle tissue of M. salmoides. It was shown that M. salmoides from each of the three impoundments are in a healthy state according to the parameters assessed. However, the presence of heavy metals, particularly mercury, uranium and zinc, do indicate the presence of human activities.
The indigenous parasites of Anguilla mossambica have been well documented including the gastrointestinal nematode Paraquimperia africana, and the stomach nematode Heliconema africanum. Indigenous parasites such as the swimbladder nematode Anguillicola papernai had no effect on the condition factor of infected and uninfected eels. However, the damage caused by the alien parasites were evident, including the first documented effects of the alien gill monogenean Pseudodactylogyrus anguillae on indigenous wild populations of the longin fin eel A. mossambica from the Eastern Cape, South Africa. Histological observations indicated that an alien gill monogenean caused hyperplasia, increase in mucous cells, rupture of pillar cells as well as telangiectasia. This alien parasite has invaded the Keiskamma and Kei River systems in the Eastern Cape, South Africa. According to the macroscopic fish health assessment index, A. mossambica from Binfield Park, Sandile and Wriggleswade Dams are in a healthy state. However, the histology-based health assessment highlighted that the effects on P. anguillae have a severe negative impact on the health of A. mossambica.
Using the macroscopic and histology-based fish health assessment, a comprehensive investigation into the fish health status of Mugil cephalus and Myxus capensis from Binfield Park Dam revealed that human effects and parasites are not the only threats to freshwater fish. Nephrocalcinosis is a non-infectious kidney disease which is characterised by abnormal calcium deposition in the kidneys of humans and some fish species. According to the macroscopic and histology-based fish health assessment, the M. cephalus and M. capensis are not in a healthy condition. The macroscopic and histology-based fish assessment indices are not stressor-specific, and therefore the cause of the poor health state of these two fish species could not be determined. A possible suggestion for the poor health of these two species is the age of the species. Because the two mullet species were stocked
into Binfield Park Dam, Ellender et al. (2012) could successfully age them accurately to ten years of age, which is the upper limit of the life span for these species.
Macroscopic and histology-based fish heath assessments were conducted on Labeo umbratus from Sandile Dam in order to determine the health of this species. Macroscopic and histology-based fish health assessment indicated that its L. umbratus are in a healthy state. The March 2012 survey specimens had a significantly higher macroscopic FHAI score than those from the July 2011 survey. The increased FHAI score was because of parasite infections, as well as discoloured livers and increased total blood plasma protein levels, which are indicators of nutritional state. However, the presence of the anchor worm parasite Lernaea barnimiana in low numbers had no significant impact on the health of L. umbratus.
The effect of the alien anchor worm parasite Lernaea cyprinacea was shown on the transloacted small mouth yellowfish Labeobarbus aeneus. It was also shown that L. aeneus are, according the macroscopic FHAI and the histology-based fish health assessment index, in a healthy state. However, the high scores observed in the macroscopic fish health assessment index were primarily as a result of the presence of the alien parasite L. cyprinacea and its associated affects on the fish host. Because of the significant impact of this alien parasite species on the translocated host species, it can be assumed that this alien parasite species will have a negative effect on the health of indigenous fish species in the Great Kei River.
It is clear from the results presented in this study that the necropsy based and histology based fish health assessment can be successfully implemented as tools to assess the effects of heavy metal pollution and alien fish parasites in freshwater fish from selected impoundments in the Amatola region, Eastern Cape Province, South Africa, thus the original hypothesis of this thesis is accepted.
Based on work done in this research the gaps in research have been identified. Due to the high levels of mercury indentified in the muscle tissue of M. salmoides from Binfield Park Dam. A human health assessment and edibility should be conducted in order to determine if the fish from Binfield Park Dam is safe for human consumption. In order to conserve South Africa’s Freshwater fish biodiversity, country wide surveys of indigenous fish species must be undertaken so that the health and the parasite diversity can be evaluated. / PhD (Zoology), North-West University, Potchefstroom Campus, 2015
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Alien species and propagules in the Antarctic : movements through space and timeLee, Jennifer Elizabeth 03 1900 (has links)
Thesis (PhD (Botany and Zoology))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Although the impacts of biological invasions are widely appreciated, a bias exists in research effort to post‐dispersal processes because of the difficulties of measuring propagule pressure and the detecting of newly established species. Here the Antarctic is used as a model system in which to quantify the initial dispersal of alien species and investigate the factors that contribute to the establishment and range dynamics of alien species once they have arrived in the region.
Human movements are known to transport alien species into the Antarctic, some of which have successfully established and had wide ranging consequences in recipient ecosystems. Considering terrestrial flora, this research found that over 700 seeds from 99 taxa, including some species known to be invasive, are transported into the Antarctic each year in association with South African National Antarctic Programme (SANAP) passenger luggage and cargo. The first ever assessment of propagule drop‐off indicated that 30‐50% of these propagules will enter the recipient environment. Further results suggested that the construction of the British Antarctic Survey Halley VI station will facilitate the transport of over 5000 seeds from 34 taxa into the region, making this a significant pathway for introductions.
Propagule pressure due to SANAP logistics is also considerable for marine species. Fouling assemblages on the external hull surfaces of the SANAP resupply vessel, the SA Agulhas, form only once the vessel’s anti‐fouling paint has been damaged by travel through sea ice and are characterised by low diversity. Ice scour prevents fouling assemblages from being transported to the Antarctic continent, but assemblages remain largely intact when travelling to sub‐Antarctic Islands. In the sea‐chests of the vessel populations of a known invasive, Mytilus galloprovincialis, were found with some individuals having survived transportation to the Antarctic region on multiple occasions.
Once species have overcome initial dispersal barriers, they face further ecological and physiological challenges in order to establish in the recipient region. The parasitoid wasp Aphidius matricariae was first recorded on Marion Island in 2001. Surveys around the island show that adult abundance and the frequency of aphid parasitism are highest adjacent to a common anchor point of the SA Agulhas and decline away from this region. Genetic diversity was low, suggesting that the population was established from a single introduction. This highlights that high propagule pressure is not necessary for successful establishment of introduced invertebrates.
Another species that has overcome the dispersal barrier is the terrestrial slug Deroceras panormitanum, which was introduced to Marion Island in the 1970’s and has since spread throughout much of the coastal habitat of the island. For this species range limits are set by intolerance of low temperature and salinity, and abundance structure is characterized by patches and gaps which are associated with this species inability to tolerate dry conditions.
To prevent further alien introductions in the region, targeted management of high risk pathways is required. In addition, increased vigilance is needed to detect and manage newly established aliens before their ranges expand. / AFRIKAANSE OPSOMMING: Alhoewel die impak van biologiese indringings in die breë waardeer word, bestaan daar vooroordeel in navorsingspogings ten opsigte van na‐verspreidingsprosesse, weens die moeilikhede om verspreidingseenheid druk te meet en in die opsporing van nuut gevestigde spesies. Hier word die Antarktiese streek as ‘n model sisteem gebruik waarin die aanvanklike verspreiding van uitheemse spesies gekwantifiseer kan word en om die faktore wat bydrae tot die vestiging en grens dinamika van uitheemse spesies te ondersoek, wanneer hulle in ’n streek aangekom het.
Menslike bewegings is bekend daarvoor om uitheemse spesies na die Antarktiek te vervoer, sommige waarvan suksesvol gevestig het en omvattende gevolge in die ontvanger ekosisteme gehad het. Aangaande terrestriële flora het hierdie navorsing gevind dat oor die 700 sade van 99 taxa, insluitende sommige spesies wat bekend is om indringend te wees, jaarliks na die Antarktiek vervoer word in assosiasie met die Suid Afrikaanse Nasionale Antarktiese Program (SANAP) se bagasie en vrag. Die eerste waardebepaling van verspreidingseenheid afgooi het aangedui dat 30‐50% van hierdie verspreidingseenhede die ontvanger omgewing sal binnedring. Verdere resultate het voorgestel dat die konstruksie van die Britse Antarktiese Opname Halley VI stasie die vervoer van 5000 sade van 34 taxa sal fasiliteer die streek in, wat dit ’n betekenisvolle weg maak vir indringings.
Verspreidingseenheid druk is ook, as gevolg van die SANAP logistiek, aanmerklik vir mariene spesies. Vuilgoed versamelings op die eksterne omhullende oppervlaktes van die SANAP her‐voorsieningsvaartuig, die SA Agulhas, vorm wanneer die vaartuig se anti‐vuilgoed verf beskadig is met reis deur see‐ys en word gekenmerk deur lae diversiteit. Ys skuring voorkom dat vuilgoed versamelings vervoer word na die Antarktiese kontinent, maar versamelings bly grootliks vasgeheg wanneer na sub‐Antarktiese eilande gereis word. Populasies van ’n welbekende indringer, Mytilus galloprovincialis, is gevind in die see‐storingsarea van die vaartuig, met sommige individue wat die vervoering na die Antarktiese streek oorleef het op verskeie geleenthede. Wanneer spesies die aanvanklike verspreidingshindernisse oorkom het, staar hulle verdere ekologies en fisiologiese uitdagings in die gesig ten einde in die ontvanger streek te vestig. Die parasitiese wespe Aphidius matricariae is vir die eerste keer op Marion aangeteken in 2001. Opnames om die eiland toon dat volwasse oorvloed en die frekwensie van plantluis parasitisme die hoogste is aangrensend die algemene ankerpunt van die SA Agulhas en afneem weg van die omgewing af. Genetiese diversiteit was laag, wat voorstel dat die populasie gevestig het van ’n enkele bekendstelling. Dit lig uit dat hoë verspreidingseenheid druk nie nodig is vir die suksesvolle vestiging van bekendgestelde invertebrata nie.
‘n Ander spesie wat die verspreidingshindernisse oorkom het is die landslak Deroceras panormitanum wat in die 1970’s op Marion Eiland bekendgestel is en wat sedertdien versprei het oor meeste van die kushabitat van die eiland. Vir hierdie spesie word grens limiete vasgestel deur onverdraagsaamheid vir lae temperature en saliniteit en die oorvloedstruktuur word gekenmerk deur laslappe en gapings wat geassosieer word met die spesie se onvermoë om droë kondisies te hanteer.
Om verdere uitheemse bekendstellings in die streek te voorkom, word geteikende bestuur van hoë risiko weë vereis. Toenemende waaksamheid is bykomend nodig vir die opsporing en bestuur van nuutgevestigde uitheemse spesies voordat hulle grense verbreed.
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Alimentação e impactos da espécie exótica bagre-africano (Clarias gariepinus Burchell,1822) no estuário do rio Itanhém, Bahia / Feeding habits and impact of the alien species African catfish (Clarias gariepinus Burchell, 1822) in Itanhaém River estuary, Bahia.Leandro Bonesi Rabelo 25 September 2009 (has links)
Este estudo foi desenvolvido com finalidade de investigar o impacto da espécie exótica Clarias gariepinus no rio Itanhém, BA, tendo como referência o rio Caravelas. Foram analisados 214 estômagos de Clarias gariepinus, Centropomus undecimalis e C. parallelus desses dois locais. Brachyura compôs 92,8% da dieta de C. parallelus do rio Caravelas, enquanto que para C. undecimalis Teleostei compôs 72,5%. No rio Itanhém, os camarões foram mais importantes na alimentação de Clarias gariepinus, e para C. parallelus, Teleostei (98,1%). Não ocorreu sobreposição alimentar em nenhum dos casos estudados. Para caracterizar a ictiofauna, foram capturados 915 indivíduos do rio Caravelas e 2644 indivíduos do rio Itanhém. A espécie mais importante de Caravelas foi Diapterus auratus, e em Itanhém foi Stellifer naso. As variações da abundância da ictiofauna estiveram associadas, principalmente, à variação da salinidade. Para caracterizar as comunidades de pescadores e a problemática do Clarias gariepinus, aplicaram-se questionários socioeconômicos. Segundo os entrevistados (17 de Caravelas e 12 de Alcobaça), a espécie exótica traz como principais problemas, insuficiência de comercialização, predação sobre camarão e diminuição da renda dos pescadores. Pelos resultados desse trabalho não foi possível detectar indícios de mudanças na população de C. parallelus do rio Itanhém, apesar do impacto econômico detectado. / This work was developed in order to investigate the impact of the alien species Clarias gariepinus in the Itanhém River comparing to the adjacent Caravelas River, where this species does not occur. A total of 214 stomachs from C. gariepinus, Centropomus undecimalis, C. parallelus were analyzed. In Caravelas River, Brachyura was the main food item for C. parallelus, and Teleostei for C. undecimalis. In Itanhém River, shrimp was the most important food for C. gariepinus, and Teleostei for C. parallelus. There was no food overlap between the species within and among rivers. To characterize the fish fauna, 915 individuals and 2,644 were captured in Caravelas and Itanhém Rivers, respectively. Diapterus auratus was the most important species in Caravelas, while Stellifer naso in Itanhém. Seasonal variability on fish fauna was related to salinity. Twenty-nine questionnaires were applied to the local fishermen in order to evaluate the impact of the Clarias gariepinus introduction on the ecosystem and fishery. The main problems reported were that the C. gariepinus has no commercial value, they prey on shrimp, and the decreasing profit from fishery. There is no evidence of changes in the Centropomus parallelus population induced by the alien species, despite of its economic impact.
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Alimentação e impactos da espécie exótica bagre-africano (Clarias gariepinus Burchell,1822) no estuário do rio Itanhém, Bahia / Feeding habits and impact of the alien species African catfish (Clarias gariepinus Burchell, 1822) in Itanhaém River estuary, Bahia.Rabelo, Leandro Bonesi 25 September 2009 (has links)
Este estudo foi desenvolvido com finalidade de investigar o impacto da espécie exótica Clarias gariepinus no rio Itanhém, BA, tendo como referência o rio Caravelas. Foram analisados 214 estômagos de Clarias gariepinus, Centropomus undecimalis e C. parallelus desses dois locais. Brachyura compôs 92,8% da dieta de C. parallelus do rio Caravelas, enquanto que para C. undecimalis Teleostei compôs 72,5%. No rio Itanhém, os camarões foram mais importantes na alimentação de Clarias gariepinus, e para C. parallelus, Teleostei (98,1%). Não ocorreu sobreposição alimentar em nenhum dos casos estudados. Para caracterizar a ictiofauna, foram capturados 915 indivíduos do rio Caravelas e 2644 indivíduos do rio Itanhém. A espécie mais importante de Caravelas foi Diapterus auratus, e em Itanhém foi Stellifer naso. As variações da abundância da ictiofauna estiveram associadas, principalmente, à variação da salinidade. Para caracterizar as comunidades de pescadores e a problemática do Clarias gariepinus, aplicaram-se questionários socioeconômicos. Segundo os entrevistados (17 de Caravelas e 12 de Alcobaça), a espécie exótica traz como principais problemas, insuficiência de comercialização, predação sobre camarão e diminuição da renda dos pescadores. Pelos resultados desse trabalho não foi possível detectar indícios de mudanças na população de C. parallelus do rio Itanhém, apesar do impacto econômico detectado. / This work was developed in order to investigate the impact of the alien species Clarias gariepinus in the Itanhém River comparing to the adjacent Caravelas River, where this species does not occur. A total of 214 stomachs from C. gariepinus, Centropomus undecimalis, C. parallelus were analyzed. In Caravelas River, Brachyura was the main food item for C. parallelus, and Teleostei for C. undecimalis. In Itanhém River, shrimp was the most important food for C. gariepinus, and Teleostei for C. parallelus. There was no food overlap between the species within and among rivers. To characterize the fish fauna, 915 individuals and 2,644 were captured in Caravelas and Itanhém Rivers, respectively. Diapterus auratus was the most important species in Caravelas, while Stellifer naso in Itanhém. Seasonal variability on fish fauna was related to salinity. Twenty-nine questionnaires were applied to the local fishermen in order to evaluate the impact of the Clarias gariepinus introduction on the ecosystem and fishery. The main problems reported were that the C. gariepinus has no commercial value, they prey on shrimp, and the decreasing profit from fishery. There is no evidence of changes in the Centropomus parallelus population induced by the alien species, despite of its economic impact.
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From 'useful and interesting' to 'evil invaders': evolving perceptions of non-native species in the United StatesRichards, Jeannine Hyde January 2002 (has links)
Boston University. University Professors Program Senior theses. / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-02
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Uso de sistema agroflorestal na implanta??o de reserva legal / Use of an agroforestry system for establishing Legal ReserveChauvet, Xavier Dominique Marie 01 August 2017 (has links)
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Previous issue date: 2017 / Estimativas indicam que 33% das terras agr?colas no mundo se encontram em algum est?gio de degrada??o, afetando principalmente a qualidade dos solos, a biodiversidade e a disponibilidade de ?gua. O Brasil concentra 140 milh?es de hectares de ?reas degradadas, dos quais 30 milh?es s?o pastagens com baix?ssima produtividade de alimento para os animais. A degrada??o do solo e dos ecossistemas nativos, bem como a dispers?o de esp?cies ex?ticas s?o as maiores e mais amplas amea?as ? biodiversidade. Em grande parte do pa?s o propriet?rio de um im?vel rural tem a obriga??o de registrar 20% da sua superf?cie como ?rea de Reserva Legal. Apesar da obrigatoriedade, em muitas propriedades ainda se verifica a sua inexist?ncia. Dentro do contexto da necessidade de implementa??o de Reserva Legal e da indisponibilidade de ?reas preservadas com vegeta??o nativa foi realizado um experimento em uma ?rea de pastagem degradada na qual se comparou o plantio isolado da aroeira do sert?o (Myracrodruon urundeuva Allem?o) com dois arranjos de sistema agroflorestal onde al?m da aroeira utilizaram-se como culturas anuais ou semi-perenes o feij?o guandu (Cajanus cajan (L) Hunth) e a mandioca (Manihot esculenta Crantz). O experimento foi implantado em ?rea de dom?nio do Bioma Cerrado. O delineamento estat?stico obedeceu ao modelo ?tipo leque? proposto por Nelder, (1962), onde analisou-se tr?s arranjos de plantio (aroeira a pleno sol, aroeira + feij?o guandu e aroeira + feij?o guandu + mandioca) em dez espa?amentos (555 a 3333 plantas de aroeira ha-1) completando 30 tratamentos. Ap?s 26 meses de implanta??o do experimento a sobreviv?ncia da aroeira foi de 100%, o crescimento da aroeira em altura, di?metro e cobertura de copa n?o foi influenciado pelos tratamentos e demostrou o car?ter calc?fila da esp?cie. A regenera??o arb?rea-arbustiva n?o foi favorecida pelo arranjo que continha aroeira, feij?o guandu e mandioca. A grande maioria da regenera??o arb?rea-arbustiva foi originada de brota??es de ra?zes pr?-existentes ? implanta??o do experimento. A regenera??o herb?cea foi influenciada pelo tipo de arranjo. O arranjo da aroeira a pleno sol permitiu a invas?o de Urochloa decumbens. O arranjo da aroeira, do feij?o guandu e da mandioca permitiu um excelente controle de herb?ceas invasoras, por?m limitou nesta fase inicial o desenvolvimento da regenera??o arbustiva-arb?rea. O arranjo com aroeira e feij?o guandu controlou a invas?o de Urochloa decumbens. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Estimates indicate that 33% of the world's agricultural land is in some stage of degradation, mainly affecting soil quality, biodiversity, and water availability. Brazil concentrates 140 million hectares of degraded areas, of which 30 million hectares are pastures with very low feed productivity. Degradation of native soil and ecosystems, and the dispersal of alien species are major and broader threats to biodiversity. The owner of a rural property has the obligation to register 20% of the area as a Legal Reserve area. Despite this obligation, in many ownerships the Legal reserve is non still existing. Within the context of the demand to recover degraded agricultural areas for the final implementation of Legal Reserve was carried out an experiment in an area of degraded pasture, in which an agroforestry system was compared with the isolated planting of an arboreal species. The arboreal species was Myracrodruon urundeuva Allem?o and the annual or semi-perennial crops were Cassava (Manihot esculenta Crantz) and Pigeon pea (Cajanus cajan (L) Hunth). The experiment was inserted in a typical Cerrado phytophysiognomy. The statistical design was based on Nelder's model (1962), where 3 plant arrangements (Aroeira, Aroeira + Pigeon pea and Aroeira + Pigeon pea + Cassava) were analyzed in 10 spacings (555 to 3333 Plants of aroeira.ha-1) completing 30 treatments. After 26 months of implantation, the survival rate of aroeira was 100%, the growth of the aroeira in height, diameter and crown cover was not influenced by treatments and expressed the calcific character of the species. The arboreal-shrub regeneration was not favored by the arrangement that contained Aroeira, Pigeon pea and Cassava. A great majority of the tree-shrub regeneration originated from rootstocks pre-existing to the implantation of the experiment. Herbaceous regeneration was influenced by the type of arrangement. The arrangement of the aroeira in full sun allowed the invasion of Urochloa decumbens. The arrangement of aroeira, pigeon pea and cassava allowed an excellent control of invasive herbaceous plants, but limited at this initial phase the development of tree-shrub regeneration. The arrangement with Aroeira and pigeon pea controlled an invasion of Urochloa decumbens.
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Densidade, genética e saúde populacional como ferramentas para propor um plano de controle e erradicação de invasão biológica: o caso de Callithrix aurita (Primates) no Parque Nacional da Serra dos Órgãos, RJ, BrasilDaniel Gomes Pereira 30 June 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A introdução de espécies em locais fora de sua distribuição natural é uma preocupação importante na conservação da biodiversidade. A espécie Callithrix aurita é endêmica das regiões de floresta de altitude da Mata Atlântica do Sudeste do Brasil. Os critérios mais relevantes que a enquadram como espécie ameaçada de extinção são: destruição do habitat, incapacidade de adaptação a florestas secundárias degradadas, declínio populacional, distribuição restrita e introdução de espécies exóticas invasoras. Estes critérios, aliados à evidente raridade, explicam a sua inclusão na Lista Oficial de Espécies da Fauna Brasileira Ameaçadas de Extinção. Os objetivos do trabalho são: estimar o tamanho populacional de C. aurita, C. penicillata e seus híbridos no Parque Nacional da Serra dos Órgãos, avaliar a hibridação entre as espécies por caracteres morfológicos e laboratoriais, verificar o estado de saúde e confirmar a participação de C. aurita na paternidade dos animais capturados, propor um plano de erradicação e de controle de invasão de C. penicillata no Parque. Os tamanhos populacionais das duas espécies de primatas foram estimados através do método Distance Sampling. Um total de sete sagüis foi capturado com armadilhas de captura viva para a contenção física e química e posterior realização dos procedimentos. Para o hemograma, as dosagens bioquímicas e as análises genéticas, o sangue foi recolhido em um tubo de ensaio contendo anticoagulante e mantido em temperatura de refrigeração até o momento da manipulação / processamento das amostras. Callithrix aurita parece estar bem preservada apenas na área do Parque correspondente ao trecho situado no município de Petrópolis. As análises citogenéticas e moleculares dos híbridos são uma ferramenta útil para confirmar se há ou não hibridação, identificando as espécies envolvidas e verificando se há tendência nos retrocruzamentos. Pode-se sugerir que existe uma tendência à diferenciação das espécies e identificação de indivíduos híbridos pelo padrão hematológico e bioquímico, a ser confirmada com uma amostragem maior de animais da espécie C. aurita, preferencialmente da mesma localidade e nas mesmas condições. No caso de C. aurita, as principais recomendações para sua conservação incluem pesquisas para o registro de outras populações em áreas de distribuição livres de invasão, para que se possa avaliar as chances de recuperação populacional e sobrevivência da espécie. A criação de novas Unidades de Conservação deve ser estimulada, assim como estudos mais aprofundados sobre a espécie nos locais já conhecidos de ocorrência, além de um programa seguro de criação em cativeiro. / The introduction of species in places outside their natural distribution is an important concern in biodiversity conservation. Callithrix aurita is endemic in regions of high-altitude forests of the Atlantic forest of southeastern Brazil. The most relevant criteria of fitting as endangered species are: habitat destruction, inability to adapt to degraded secondary forests, population decline, restricted distribution and introduction of invasive alien species. These criteria, coupled with the apparent rarity, explain its inclusion on the Official List of Species of Brazilian Fauna Threatened with Extinction. The objectives are: to estimate the population size of C. aurita, C. penicillata and their hybrids in the Serra dos Órgãos National Park, assess hybridization between species by morphology and laboratory check the health status and confirm the involvement of C. aurita in the fatherhood of trapped animals, propose a plan for eradication and control of invasion of C. penicillata in the Park. The population sizes of the two primate species were estimated by the method "Distance Sampling". A total of seven marmosets were captured with live traps set for the chemical and physical restraint and subsequent completion of the procedures. For the haemogram, the biochemical and genetic analysis, blood was collected in a test tube containing anticoagulant and kept at refrigerator temperature until the moment of handling / processing of samples. Callithrix aurita appears to be well preserved only in the park area corresponding to the portion located in the city of Petrópolis. The cytogenetic and molecular analysis of hybrids are a useful tool to confirm whether or not hybridization, identifying the species involved and seeing if there is a tendency in the backcrosses. One may suggest that there is a tendency for species differentiation and identification of hybrid individuals by standard hematological and biochemical, to be confirmed with a larger sample of the species C. aurita, preferably from the same locality and under the same conditions. In the case of C. aurita, the main recommendations for its conservation research to include the registration of other populations in areas of distribution free of intrusion, so you can evaluate the chances of population recovery and species survival. The creation of new protected areas should be encouraged, as well as more detailed studies on the species already known sites of occurrence, and a safe program of captive breeding.
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Densidade, genética e saúde populacional como ferramentas para propor um plano de controle e erradicação de invasão biológica: o caso de Callithrix aurita (Primates) no Parque Nacional da Serra dos Órgãos, RJ, BrasilDaniel Gomes Pereira 30 June 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A introdução de espécies em locais fora de sua distribuição natural é uma preocupação importante na conservação da biodiversidade. A espécie Callithrix aurita é endêmica das regiões de floresta de altitude da Mata Atlântica do Sudeste do Brasil. Os critérios mais relevantes que a enquadram como espécie ameaçada de extinção são: destruição do habitat, incapacidade de adaptação a florestas secundárias degradadas, declínio populacional, distribuição restrita e introdução de espécies exóticas invasoras. Estes critérios, aliados à evidente raridade, explicam a sua inclusão na Lista Oficial de Espécies da Fauna Brasileira Ameaçadas de Extinção. Os objetivos do trabalho são: estimar o tamanho populacional de C. aurita, C. penicillata e seus híbridos no Parque Nacional da Serra dos Órgãos, avaliar a hibridação entre as espécies por caracteres morfológicos e laboratoriais, verificar o estado de saúde e confirmar a participação de C. aurita na paternidade dos animais capturados, propor um plano de erradicação e de controle de invasão de C. penicillata no Parque. Os tamanhos populacionais das duas espécies de primatas foram estimados através do método Distance Sampling. Um total de sete sagüis foi capturado com armadilhas de captura viva para a contenção física e química e posterior realização dos procedimentos. Para o hemograma, as dosagens bioquímicas e as análises genéticas, o sangue foi recolhido em um tubo de ensaio contendo anticoagulante e mantido em temperatura de refrigeração até o momento da manipulação / processamento das amostras. Callithrix aurita parece estar bem preservada apenas na área do Parque correspondente ao trecho situado no município de Petrópolis. As análises citogenéticas e moleculares dos híbridos são uma ferramenta útil para confirmar se há ou não hibridação, identificando as espécies envolvidas e verificando se há tendência nos retrocruzamentos. Pode-se sugerir que existe uma tendência à diferenciação das espécies e identificação de indivíduos híbridos pelo padrão hematológico e bioquímico, a ser confirmada com uma amostragem maior de animais da espécie C. aurita, preferencialmente da mesma localidade e nas mesmas condições. No caso de C. aurita, as principais recomendações para sua conservação incluem pesquisas para o registro de outras populações em áreas de distribuição livres de invasão, para que se possa avaliar as chances de recuperação populacional e sobrevivência da espécie. A criação de novas Unidades de Conservação deve ser estimulada, assim como estudos mais aprofundados sobre a espécie nos locais já conhecidos de ocorrência, além de um programa seguro de criação em cativeiro. / The introduction of species in places outside their natural distribution is an important concern in biodiversity conservation. Callithrix aurita is endemic in regions of high-altitude forests of the Atlantic forest of southeastern Brazil. The most relevant criteria of fitting as endangered species are: habitat destruction, inability to adapt to degraded secondary forests, population decline, restricted distribution and introduction of invasive alien species. These criteria, coupled with the apparent rarity, explain its inclusion on the Official List of Species of Brazilian Fauna Threatened with Extinction. The objectives are: to estimate the population size of C. aurita, C. penicillata and their hybrids in the Serra dos Órgãos National Park, assess hybridization between species by morphology and laboratory check the health status and confirm the involvement of C. aurita in the fatherhood of trapped animals, propose a plan for eradication and control of invasion of C. penicillata in the Park. The population sizes of the two primate species were estimated by the method "Distance Sampling". A total of seven marmosets were captured with live traps set for the chemical and physical restraint and subsequent completion of the procedures. For the haemogram, the biochemical and genetic analysis, blood was collected in a test tube containing anticoagulant and kept at refrigerator temperature until the moment of handling / processing of samples. Callithrix aurita appears to be well preserved only in the park area corresponding to the portion located in the city of Petrópolis. The cytogenetic and molecular analysis of hybrids are a useful tool to confirm whether or not hybridization, identifying the species involved and seeing if there is a tendency in the backcrosses. One may suggest that there is a tendency for species differentiation and identification of hybrid individuals by standard hematological and biochemical, to be confirmed with a larger sample of the species C. aurita, preferably from the same locality and under the same conditions. In the case of C. aurita, the main recommendations for its conservation research to include the registration of other populations in areas of distribution free of intrusion, so you can evaluate the chances of population recovery and species survival. The creation of new protected areas should be encouraged, as well as more detailed studies on the species already known sites of occurrence, and a safe program of captive breeding.
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