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Habitat selection and movements of Taiga Bean Geese Anser fabalis fabalis during spring and early summerVahlström, Isak January 2017 (has links)
Habitats vary in terms of food and predation risk between each other and over time. The aim of this study was to describe the daily cycle of habitat selection and movements of Taiga Bean Geese Anser fabalis fabalis during spring and early summer. For that I used data from 11 Taiga Bean Geese marked with GPS-transmitters in Vilhelmina county, Sweden. I coded every position to a habitat and calculated length of movements between the positions. In most cases the geese spent the night at wetlands and agricultural fields, probably feeding, and the day close to lakes and streams, probably resting. The geese moved between those habitats in the morning and in the evening. These movements between habitats are more likely due to change in predation pressure than resource depletion of the first habitat.
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Drivers of Nest Success and Stochastic Population Dynamics of the Common Eider (Somateria mollissima)Iles, David Thomas 01 May 2012 (has links)
Anthropogenic perturbations to Arctic ecosystems have influenced large-scale climate processes, as well as finer-scale ecological relationships within and amongst populations of species. Life history theory predicts a trade-off between the temporal variation in a vital rate and its impact on population dynamics. Here, we examine the drivers of long-term variation in reproductive success in a sub-Arctic common eider (Somateria mollissima) colony, and evaluate the impacts of variation in reproductive success on eider population dynamics. In Chapter 2, we develop a suite of nest survival models to evaluate the effects of variation in predator abundance, the availability and spatial distribution of alternative prey, and breeding season climate on annual common eider nest success. Eider nest success declined across the 41 years of study, but was also highly variable across years. Annual variation in nest success was driven by a complex interaction between predators and alternative prey, as well as breeding season climate. Our results suggest that increased abundance of snow geese (alternative prey) may buffer annual fluctuations in arctic fox abundance, yet result in a long-term decline in eider nest success suggesting apparent competition via other predator species (e.g. gulls). The effect of breeding season climate was subtle compared to the influence of biotic factors and indicated that cold, wet conditions in early spring were correlated with decreased nest success, while warm, wet conditions in late spring increased eider nest success. In Chapter 3 we develop a stochastic population model to evaluate the relative effects of variation and covariation amongst multiple vital rates on population dynamics, and determine the impact of long-term changes in the abundance of alternative prey on eider population dynamics. Consistent with life history predictions, we found that proportional changes in adult survival have the largest impact on population dynamics, yet high variation in the vital rates underlying fertility contribute more to actual variation in population growth. The eventual exodus of alternative prey from the eider colony reduced the long-term growth rate, primarily through negative impacts on mean nest success.
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Evolution of Molting Areas of Great Basin Canada GeeseArneson, Paul D. 01 May 1970 (has links)
Environmental factors at Neponset and Woodruff Narrows reservoirs were evaluated to determine their effects on molting Canada geese. More geese utilized Woodruff Narrows. Geese apparently favored the larger expanse of open water and adequate food supply.
Most of the molting geese were from the Bear River drainage. Some geese came from scattered areas in Utah, Idaho, Wyoming, and Montana. After molting, the geese flew to migration staging areas in southeastern Idaho before migrating to wintering areas in southern California and Arizona.
Females outnumbered males by 6 percent. The mean annual mortality rate for adult geese was 42 percent. Recovery rates between the sexes were not significantly different (P≤0.01). Juvenile geese were 1.4 times more vulnerable than adults to hunting mortality. Hunting pressure on the geese at the reservoirs was not great enough to be detrimental to the flock.
Of 89 nests, 53 percent were successful . Mean clutch size was 4.85 eggs per nest with a range of 1-7. Mammalian and avian predators destroyed 25 percent of the eggs. Forty-seven broods were observed with an average brood size of 4.77 young.
Other water fowl populations did not affect the goose population.
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Waterfowl foods and use in managed grain sorghum and other habitats in the Mississippi Alluvial ValleyWiseman, Alicia Joy 11 December 2009 (has links)
Grain sorghum provides energy-rich seeds for waterfowl. I conducted experiments in 22 sorghum fields in Arkansas, Mississippi, and Louisiana during falls 2006 – 2007 to evaluate abundance of ratoon grain (i.e., second crop after harvest), waste grain, and natural seeds. I also conducted surveys of wintering waterfowl in flooded croplands and moist-soil wetlands to evaluate if ducks and geese differentially used habitats. Fertilized plots in 2007 produced >4 times more ratoon grain (x = 219.57 ± 39.65 [SE] kg/ha) than other treatments. Fertilized plots in southern regions of my study area produced ~5 times more ratoon grain (x = 262.93 ± 50.28 kg/ha) than others. Mallards and other ducks used moist-soil wetlands (x >65 ducks/ha) more than other habitats. I did not observe geese using flooded sorghum. I recommend not manipulating sorghum stubble after harvest, fertilizing, and flooding it after ratoon grain has matured, and integrating moist-soil wetlands into agricultural lands.
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The Evualation of the Position of Economic Zone of the West Coast of the Taiwan Strait from the Perspective of Taiwan¡¦s Global Economic & Trade StrategyChen, Wei-cheng 05 September 2011 (has links)
In this paper I start from the exploration of the change of industrial structure during the economic development in Taiwan after World War II. Through the document analysis, I find out the reasons why the manufacture and service industries move outside to mainland China and other areas around the world are because of the extension of market and the cut down of cost. Since China is the most important trade partner of Taiwan, I focus the study on the economic zones in China, especially the economic zone of West Coast of Taiwan Strait (West Coast economic zone).
The argument of this paper is that Taiwan should take advantage of the favor policy of economic zones in China and build the supply chain in the certain economic zones with local comparative advantage industries. And the evaluation of Taiwan¡¦s economic strategy depends on which economic zone in China can offer the supply chain advantage industries with the need of Taiwan¡¦s industries.
After the comparison of the current trends of the investment of Taiwanese businessmen in West Coast economic zone and other economic zones in mainland China, I find out West Coast economic zone is not Taiwanese businessmen¡¦s best choice to invest. To attract more investments from Taiwan, the authority of West Coast economic zone should alter its favor policy according to co-opettion strategy and to meet the need of Taiwan industries.
In conclusion, I suggest the authorities on both side of Taiwan strait should offer the need of local comparative advantage industries according to the supply chain theory, by this way, we can get a win-win result for the both side of Taiwan Strait.
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Estudo de parâmetros clínicos, imunitários e do proteinograma sérico da vacinação contra a doença de Newcastle em gansos-da-China (Anser cygnoides) : pesquisa do estado portador do vírus e sua importância epidemiológica /Campioni, Josie Maria. January 2009 (has links)
Orientador: Antonio Carlos Paulillo / Banca: Ângela Cleusa de Fátima Banzatto de Carvalho / Banca: Márcia Nishizawa / Resumo: Parâmetros clínicos, imunitários, proteinograma sérico e epidemiológicos da vacinação em gansos-da-China foram avaliados por três experimentos. Amostras vacinais Ulster 2C, B1 e La Sota do VDN foram utilizadas. A importância epidemiológica e pesquisa do estado de portador do VDN também foram avaliadas. No experimento 1, foram utilizados 120 gansos-da-China de um dia a 60 dias de idade, distribuídos em 4 tratamentos com 30 animais, submetidos a diferentes esquemas imunoprofiláticos. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Após o desafio frente a uma estirpe patogênica do VDN, aos 60 dias de vida das aves, em todos os grupos, realizou-se a extração de RNA viral através da reação de cadeia de polimerase pós Transcrição Reversa (RT-PCR). No experimento 2, foram utilizadas aves SPF conviventes com gansos-da-China inoculados com uma estirpe patogênica do VDN, decorridos seis, 10 e 20 dias da infecção experimental, após a infecção com o VDN, nas duas espécies, empregou-se a técnica do RT-PCR. Observou-se a transmissão de vírus patogênico (VDN) dos gansos-da- China para as aves SPF conviventes decorridos até 14 dias da infecção experimental com este patógeno, o que vem realçar a importância do ganso-da-China como fonte potencial de infecção de VDN para aves domésticas No experimento 3, foram determinadas as concentrações séricas das proteínas totais, albumina e globulinas das aves vacinadas e não vacinadas contra a doença de Newcastle. Notou-se que aos 42 dias de idade, de forma geral, os gansos vacinados com as estirpes Ulster 2C, B1 e Lasota apresentaram diferença de forma significativa em relação ao grupo controle para as concentrações séricas de albumina, especialmente o grupo vacinado com a estirpe LaSota. / Abstract: The clinical, epidemiological, immunological parameters and the serum proteinogram of vaccination in Chinese geese were investigated using 3 experiments. Ulster 2C, B1 and LaSota vaccines strains of the NDV were used. In experiment 1, 120 one-day-old Chinese geese were used, and divided into 4 different groups with 30 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 60 days of age. After challenge, in all the groups, tracheal and cloacal swabs were collected for RT-PCR. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged Chinese geese were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 20 days after experimental infection. The vaccinated groups of Chinese geese did not present any genetic material of virus in the RT-PCR. Therefore, these results show the relevance of vaccination in suppressing a NDV carrier state in the Chinese geese. In experiment 2, SPF chickens housed with Chinese geese which were previously inoculated with a pathogenic NDV strain, developed severe and characteristic NDV lesions and died, after five and 14 days. In experiment 3, the serum proteinogram showed significantly differences for albumin concentrations between the vaccinated and the control group at 42 days of age, especially the birds vaccinated with LaSota strain. / Mestre
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Legacy Effects of Habitat Degradation by Lesser Snow Geese on Ground-Nesting Savannah Sparrows along the Hudson Bay LowlandsPeterson, Stephen L. 01 May 2013 (has links)
Increased growth of the mid-continent population of Lesser Snow Geese (LSGO) has led to the degradation of coastal salt marsh and sedge meadow habitats across Canadian Arctic and sub-Arctic ecosystems. It is believed that a human-induced trophic cascade caused by agricultural habitat modification along migratory routes and wintering grounds has contributed to the increase in LSGO numbers, which has resulted in the alteration of habitat quality and connectivity along northern breeding and stopover sites used by various avian species. This habitat degradation has been shown to decrease the presence and temporal persistence of ground-nesting passerine and shorebird species at a local level and may lead to decreases of Arctic / sub-Arctic breeding avian species across landscapes that LSGO utilize and degrade.
In 1999, four paired study plots were established, and used in conjunction with a single study plot from 1976, in order to measure the composition of habitat parameters (barren ground extent; graminoid and shrub cover) and to estimate the number of avian nests found in these plots. Using this historical data along with our findings from 2010 and 2011, our main objectives were to: 1) document the change in the aforementioned habitat parameters over time; 2) estimate the local nesting occupancy rates of the common Savannah Sparrow (SAVS), a robust and adaptable ground nester; and 3) determine which habitat variables are indicative of the rates of change and occurrence of nesting by SAVS within the study plots.
By using ANOVA, linear mixed effects, and multi-state occupancy models, results suggest that an increase in barren ground, decreases in shrub and graminoid cover, and a loss of connectivity between suitable nesting patches has led to a 10% (λ = 0.90) annual decline in the probability that SAVS nesting occurred across the study plots from 1999 to 2010.
These model results may be used to estimate long-term trends in persistence of breeding SAVS and other similar ground-nesting avian species that share habitats with LSGO along Arctic and sub-Arctic ecosystems. (93 pages)
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Comparative breeding ecology in arctic-geese of different body size : an example in ross's and lesser snow geeseTraylor, Joshua James 02 July 2010
Two closely-related, different-sized species of geese nest sympatrically south of the Queen Maud Gulf (QMG) in Canadas central arctic. Following a period of high population growth rate in both species within the QMG, the population growth rate of larger-bodied lesser snow geese (Chen caerulescens caerulescens; hereafter snow geese) has slowed most recently to roughly half that observed in smaller-bodied Rosss geese (Chen rossii). I focused on factors that influence productivity and recruitment in these two species, to improve our understanding of life history variation associated with interspecific differences in body size, and to test for density-dependent population responses. I used long-term data (1991 to 2008) to compare spring nutrient reserves, breeding strategies, clutch sizes, nest success, and juvenile survival in Rosss and snow geese breeding at Karrak Lake, Nunavut; a large breeding colony located within the QMG.<p>
Long-term patterns of spring body condition (i.e., fat and protein reserves) diverged in prospective breeding female Rosss and snow geese implying that differences in food acquisition ability had become more acute. Snow geese displayed larger reductions in protein and fat reserves through time compared to Rosss geese thereby suggesting a differential density-dependent response in the ability to store nutrient reserves, a prerequisite for breeding in both species. Decreased per capita food availability influenced the timing of reproduction in both species. Nesting phenologies of Rosss and snow geese, adjusted for variation in phenology of local spring climate, have become later by 6.5 and 5.0 days, respectively, since 1991. Nutritional strategies (i.e., reliance on reserves versus local food) used for clutch formation differed between species. Rosss geese displayed greater reliance on stored reserves (i.e., capital breeding) than did snow geese, though both used endogenous reserves (> 62% of yolk protein, > 48% of albumen, and > 73% of yolk lipid) for clutch formation. Rosss and snow geese experienced declines of 28% and 23% in body masses from arrival to post-laying and also until hatch demonstrating that endogenous reserves are the main nutrient sources for incubation. Still, constraints of small size forced Rosss geese to use a mixture of local food plants and reserves for incubation metabolism.<p>
I then examined differences in clutch size, nest success, and juvenile survival to understand of the role of recruitment in the interspecific divergence of population trajectories. I did not find strong interspecific differences in clutch size and nest success. Overall, snow geese had a larger mean clutch size, which was expected based on benefits of a larger-body size. Clutch sizes decreased with delays in breeding and decreasing protein reserves of arriving females, although Rosss geese displayed larger declines with decreasing protein reserves. Mean apparent nest success for Rosss geese was 4.5% higher compared to snow geese. Nest success showed large declines (11%) in both species with increasing population size at the breeding colony. However, nest success of snow geese decreased twice as fast with delays in breeding compared to Rosss geese. Last, I found no evidence of negative density dependence in juvenile survival over time. Juvenile survival was higher in snow geese (48%) compared to Rosss geese (38%), consistent with a life history prediction based on body size differences. Despite lower juvenile survival, recruitment by Rosss geese is likely greater than that of snow geese because of earlier sexual maturity, higher breeding probability and/or greater nest success.<p>
Ultimately, small body size of Rosss geese may produce an ideal life history schedule under resource limitation at this colony i.e., one that maximizes fitness compared to larger snow geese. Life history characteristics of Rosss geese (e.g., absolutely lower energy requirement, have a flexible breeding strategy, higher reproductive effort, an earlier age of sexual maturity, a shorter breeding cycle allowing delayed arrival and nest initiation on arctic breeding areas, and shorter time required by goslings to attain adult size), in addition to their smaller bill morphology may allow exploitation of a wider niche space (i.e., one that includes marginal quality and low quantity vegetation) relative to snow geese. Because there were no large differences in components of recruitment considered here, other components of recruitment (age of sexual maturity, breeding probability) may be affected more strongly by diminished spring nutrition in snow geese and thus have a larger influence on local population dynamics.
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Comparative breeding ecology in arctic-geese of different body size : an example in ross's and lesser snow geeseTraylor, Joshua James 02 July 2010 (has links)
Two closely-related, different-sized species of geese nest sympatrically south of the Queen Maud Gulf (QMG) in Canadas central arctic. Following a period of high population growth rate in both species within the QMG, the population growth rate of larger-bodied lesser snow geese (Chen caerulescens caerulescens; hereafter snow geese) has slowed most recently to roughly half that observed in smaller-bodied Rosss geese (Chen rossii). I focused on factors that influence productivity and recruitment in these two species, to improve our understanding of life history variation associated with interspecific differences in body size, and to test for density-dependent population responses. I used long-term data (1991 to 2008) to compare spring nutrient reserves, breeding strategies, clutch sizes, nest success, and juvenile survival in Rosss and snow geese breeding at Karrak Lake, Nunavut; a large breeding colony located within the QMG.<p>
Long-term patterns of spring body condition (i.e., fat and protein reserves) diverged in prospective breeding female Rosss and snow geese implying that differences in food acquisition ability had become more acute. Snow geese displayed larger reductions in protein and fat reserves through time compared to Rosss geese thereby suggesting a differential density-dependent response in the ability to store nutrient reserves, a prerequisite for breeding in both species. Decreased per capita food availability influenced the timing of reproduction in both species. Nesting phenologies of Rosss and snow geese, adjusted for variation in phenology of local spring climate, have become later by 6.5 and 5.0 days, respectively, since 1991. Nutritional strategies (i.e., reliance on reserves versus local food) used for clutch formation differed between species. Rosss geese displayed greater reliance on stored reserves (i.e., capital breeding) than did snow geese, though both used endogenous reserves (> 62% of yolk protein, > 48% of albumen, and > 73% of yolk lipid) for clutch formation. Rosss and snow geese experienced declines of 28% and 23% in body masses from arrival to post-laying and also until hatch demonstrating that endogenous reserves are the main nutrient sources for incubation. Still, constraints of small size forced Rosss geese to use a mixture of local food plants and reserves for incubation metabolism.<p>
I then examined differences in clutch size, nest success, and juvenile survival to understand of the role of recruitment in the interspecific divergence of population trajectories. I did not find strong interspecific differences in clutch size and nest success. Overall, snow geese had a larger mean clutch size, which was expected based on benefits of a larger-body size. Clutch sizes decreased with delays in breeding and decreasing protein reserves of arriving females, although Rosss geese displayed larger declines with decreasing protein reserves. Mean apparent nest success for Rosss geese was 4.5% higher compared to snow geese. Nest success showed large declines (11%) in both species with increasing population size at the breeding colony. However, nest success of snow geese decreased twice as fast with delays in breeding compared to Rosss geese. Last, I found no evidence of negative density dependence in juvenile survival over time. Juvenile survival was higher in snow geese (48%) compared to Rosss geese (38%), consistent with a life history prediction based on body size differences. Despite lower juvenile survival, recruitment by Rosss geese is likely greater than that of snow geese because of earlier sexual maturity, higher breeding probability and/or greater nest success.<p>
Ultimately, small body size of Rosss geese may produce an ideal life history schedule under resource limitation at this colony i.e., one that maximizes fitness compared to larger snow geese. Life history characteristics of Rosss geese (e.g., absolutely lower energy requirement, have a flexible breeding strategy, higher reproductive effort, an earlier age of sexual maturity, a shorter breeding cycle allowing delayed arrival and nest initiation on arctic breeding areas, and shorter time required by goslings to attain adult size), in addition to their smaller bill morphology may allow exploitation of a wider niche space (i.e., one that includes marginal quality and low quantity vegetation) relative to snow geese. Because there were no large differences in components of recruitment considered here, other components of recruitment (age of sexual maturity, breeding probability) may be affected more strongly by diminished spring nutrition in snow geese and thus have a larger influence on local population dynamics.
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台日中區域經濟整合之機遇與策略研究 / The Opportunities and Strategies of Regional Economic Integration among Taiwan, Japan and China林香吟, Kogin Hayashi Unknown Date (has links)
當今,臨區域性或世界性經濟整合風潮下,與台灣經濟發展密切之兩個鄰邦厥為中國大陸與日本。過去,日本學者提出雁行理論從詮釋台灣經濟奇蹟的發展模式與產業變遷歷程。然而近年來,中國大陸國民所得總量已超越日本成為世界第二大經濟體,而台灣經濟停滯於亞洲四小龍之末,又有經濟轉型瓶頸危機。因此,台灣須一方面保持與日本之傳統經貿關係,另方面,也需加強與中國大陸之經濟合作,以維台灣經濟成長動能。然而,不論台灣與中國大陸或日本之經濟合作,其實是一種既有合作又有競爭的動態關係。
在客觀環境上,台灣是海島型經濟,全球化與區域經濟自由貿易是目前左右全球經濟發展的兩股潮流。近年來,台灣薪資成長率與經濟成長率皆居亞洲四小龍之末以及產業升級瓶頸難以突破等問題,皆導致台灣經濟減速或失去動能等現象。基本上,台灣目前所處時代潮流,外有世界性或區域性經濟整合風潮,內有產業結構轉型瓶頸有待突破。因此,就外環境衝擊研究,本文擬對區域經濟整合做觀察與描述性探討,並在區域經濟整合基礎上,本文提出「兩岸經濟轉型理論」(或稱兩翅理論,以隱喻兩岸經濟之起飛)以為消解內部轉型困境之方,或為台灣產業轉型提供建言,並擬就兩岸目前既有或未來進一步的經濟合作做出理論性探討。在產業合作與未來展望上,本文提出以台灣服務業結合大陸經濟發展,以進軍全球市場。 / Today, under the regional or global economic integrational trend, Taiwan's economic development is closely dedicated by two neighboring countries, China and Japan. From the past, Japanese scholars has advocated from the flying geese paradigm for interpreting on Taiwan's economic miracle to the industrial transformation model. However, in recent years, the total national income in China has overtaken Japan to become the world's second largest economy, while Taiwan's economic stagnation causes the bottom of Four Asian Tigers.
There are bottlenecks in economic transition crisis. Taiwan should maintain the traditional trade and economic relations with Japan. On the other hand, Taiwan should strengthen economic cooperation with the Mainland China in order to achieve Taiwan's economic growth momentum. However, regardless of the economic cooperation between Taiwan and Mainland China or Taiwan with Japan, their relationship becomes coopetition (a kind of both cooperation and competition) in a dynamic environment. Since Taiwan is an island-based economy, economic globalization and regional free trade is currently on the board. In recent years, Taiwan's economic growth rate and wage growth rate are far behind Four Asian Tigers and difficult to break through the bottleneck of industrial transformation. These are all leading to Taiwan's economic slowdown or loss of kinetic energy.
Basically, in the current trend in which Taiwan and outside global or regional economy, there are industrial restructuring bottlenecks to be breakthrough. Therefore, in this paper on the regional economic integration, I observe and describe based on the proposal of "cross-strait economic transformation theory" (also known as Liang Chi theory, the metaphor of cross-strait economic takeoff ) that digests the internal party difficulties in transition, or provides suggestions for Taiwan's industrial transformation, and intends to maintain good relationships of two sides (Japan and Mainland China) for the further economic cooperation. On industrial cooperation and future prospects, we propose to combine service industry (finance, cultural and creative industries and so on) of Taiwan’s experience learnt from Japan, and the vast developing space in Mainland China’s service market, there is a chance to enter the global service market.
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