Literature type: Thesis
Language: English
Full reference: Markkola, J. 2022. Ecology and conservation of the Lesser White-fronted Goose Anser erythropus. , PhD thesis, Acta Universitatis Ouluensis. A Scientiae Rerum Naturalium 770. Faculty of Science, University of Oulu, Finland.
Keywords: spring arrival, Anser erythropus, Anser fabalis, breeding schedule, habitat, diet selection, meadow management, population genetic structure, Finland
Abstract:
I studied the rare and threatened lesser white-fronted goose (Anser erythropus), abbreviated LWfG in 1989–1996 in sub-arctic Finnish Lapland (I). The studied subpopulation consisted of 2–15 breeding pairs annually. A total of 30 broods were observed with an average of 2.9 goslings per brood. The 1st year survival of tagged 10 geese was low. Satellite locations, recoveries and resightings were received from NW Russia, Kazakhstan and the Azov Sea area. Cold spells had a negative, and the sum of effective temperatures by 5 July a positive influence on reproduction. Habitat selection (II) was studied in the same area. LWfG preferred the vicinity of water, flat close-range landscape, low forest height and intermediate relative altitudes. LWfG aggregated in the vicinity of conspecifics within the preferred habitats. The averaged RSF model assigned observation and random points correctly with 83.4% success. Locations of historical observations of LWfG matched the predicted distribution of breeding sites. (III) Spring migration patterns on the Bothnian Bay coast of LWfG were examined in 1907–1916 and 1949–2014 and the taiga bean goose (Anser fabalis fabalis) in 1975–2014. Arrival of the short-distance migrant A. fabalis advanced more and earlier than the long-distance migrant A. erythropus, 10.9 days since late 1980’s vs. 5.3 days since the beginning of the 2000’s. In the LWfG, the best model for explaining variation in timing included global and local temperatures, in A. fabalis global and local temperatures and winter NAO. Increasing global temperatures seem to explain trends in both. In the spring staging places of the Bothnian Bay almost all dietary items of the LWfG were Monocotyledons, mostly grasses growing in extensive sea-shore meadows (IV). Only Phragmites, Festuca and possibly Triglochin palustris were preferred. Lesser White-fronts preferred extensive natural meadows. Mowing and grazing benefit the restoration of habitats. Genetic structuring of the LWfG was examined in its whole distribution area from Fennoscandia to East Asia (V). A fragment of the control region of mtDNA was sequenced from 110 individuals. 15 mtDNA haplotypes were assigned to two mtDNA lineages. Molecular variance showed significant structuring among populations: the main western in north-western Russia – Central Siberia, the main eastern in East Asia and the Nordic one, which earns a status as an independent management unit.
Literature type: Thesis
Language: English
Download:Full reference: Marolla, F. 2020. Understanding and forecasting population dynamics in changing arctic ecosystems. A holistic approach to study the effects of environmental changes on arctic populations of management concern. , Doctoral thesis, Department of Arctic and Marine Biology, The Arctic University of Norway.
Keywords: population dynamics, culling, mortality, production, Fennoscandia
Literature type: Thesis
Language: Chinese (Mandarin) (In Chinese with English abstract and legends)
Download:Full reference: Ao, P. 2020. Migration strategies and conservation of two large-bodied Anatidae species in East Asia. , Master thesis, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. 105 pp.
Keywords: Satellite tracking, Migration strategy, Land use, Conservation status, China, Yangtze River, Dongting Lake, Poyang Lake, Shengjin Lake
Abstract:
The East Asian-Australasian Flyway (EAAF) is the most threatened flyway in the world. China is located in the center of the EAAF where more than one million Anatidae waterbirds winter every year. With the economic development in China, the loss of wetland has resulted in the declining waterfowl diversity and abundance. In order to conserve the waterfowl population and their habitats in China, it is urgent to define the distribution of key species, determine the distribution of key species and obtain the population estimates and historical changes, the location, land use and conservation status of key habitats. Based on satellite tracking, remote sensing data, field survey, ringing resightings, literature review and expert knowledge, we studied the Whooper Swan Cygnus cygnus, a common species, and the Lesser White-fronted Goose Anser erythropus, a global threatened species. The main results are: Satellite tracking, field survey, ringing resightings, literature review and expert knowledge found the East Asian populations of Whooper Swans summered from Yenisei River in the west to Anadyr River in the East, south to the border between China and Mongolia, and wintered in Xinjiang, Gansu, Qinghai, Beijing, middle and lower reaches of Yellow River in China, South Korea and Japan. The Whooper Swans that summered in central and western Mongolia, wintered in China; swans that summered in eastern Mongolia, wintered in China and South Korea; and swans that summered in Far East Russia, wintered in Japan. The East Asian population of Whooper Swans was estimated as 57,700, which increased compared to that in 2011 (42,000-47,000 individuals). Eight key wintering sites were found in Xinjiang, Qinghai, Henan and Shandong in China, six in the coastal and inland wetlands in South Korea and 14 in Hokkaido, Miyagi, and Iwate counties in Japan. Satellite tracking, ringing resightings and remote sensing data identified five wintering areas of Whooper Swans that summered in western Mongolia, namely, Xinjiang (12%), Gansu-Qinghai (16%), Henan-Shanxi-Shaanxi (51%), Beijing (2%), Shandong (19%), from west to east. The population growth may be related to the artificial food of two largest wintering areas (Henan-Shanxi-Shaanxi and Shandong). Tracked swans mainly used water in autumn, winter and summer (82% in autumn, 74% in winter and 62% in summer), and cultivated land (64%) in spring. 47% of the GPS fixes were in protected areas in summer, higher than those in winter (35%), spring (0%) and autumn (26%). The mean migration duration in spring was 21 days (range March 1 - April 15), and in autumn it was 14 days (range October 3 - November 13). At the same time, it is found that the conservation proportion in spring was 0. Therefore, it is suggested to strengthen the conservation of important stopover sites of the Whooper Swan in the bend of the Yellow River. The migration speed in spring was slower than that in autumn, due to more stopover sites and longer stopover duration in spring, which does not support the classic migration theory which claims that spring migration should be faster than autumn migration. Satellite tracking, field survey, literature review and expert knowledge found that the East Asian Lesser White-fronted Geese that summered from the Anabas River in the west to the Anadyr River in the east, and to the Far East Taiga in the south, wintered in the middle and lower Yangtze River in China, South Korea and Japan. The East Asian population of Lesser White-fronted Geese was estimated as 4,200, which declined compared to that in 2015 (16,000 individuals). East Dongting Lake in Hunan Province is the most important wintering site for Lesser White-fronted Geese, followed by Poyang Lake in Jiangxi Province and Caizi Lake in Anhui Province, and one key wintering site in Miyagi County in Japan. Satellite tracking and remote sensing data found that the major wintering sites of the tracked Lesser White-fronted Geese were Dongting Lake (50%), Poyang Lake (24%) and Shengjin Lake (18%) in China, and they summered in the Arctic tundra of Russia and Far East Taiga. The tracked geese mainly used cultivated land (52% in spring and 45% in autumn), tundra in summer (63%) and wetland (66%) in winter. 87% of the GPS fixes were in protected areas in winter, higher than that in spring (37%), autumn (28%) and summer (7%). The breeding area were located in the less populated Arctic tundra, although the proportion in protected area in summer was low. The Lesser White-fronted Goose was more concentrated in nature reserves during the wintering period, thus the conservation proportion in wintering area is high. Dongting Lake is the largest wintering site. However, its hydrological changes resulted in the decrease of food, degradation of habitats, and might have led to the decrease of population. Therefore, it is suggested to restore and maintain of the natural hydrological process of the wintering habitat of geese. At the same time, the conservation proportion in spring and autumn was relatively low, so it is suggested to strengthen the conserve of Northeast Plain in China, the main stopover sites in spring and autumn. The migration speed of Lesser White-fronted Geese in spring was slower than that in autumn, mainly due to the longer stopover duration in spring, which does not support the classic migration theory. Both the Whooper Swan and the Lesser White-fronted Goose are large-bodied Anatidae waterbirds in EAAF. The overall conservation proportion of the Lesser White-fronted Goose is higher than Whooper Swan, but the number decreased, which may be related to its unique requirement of food and habitat. The Lesser White-fronted Goose was affected by the decrease of food resources caused by the hydrological change of the Yangtze River, while the swan was affected by local conservation measures. Therefore, we suggest conservation strategies for these two species that faced different conservation challenge: the key point for the conservation of the Lesser White-fronted Geese is the restoration and maintenance of the natural hydrological process in the wintering area, and that of the Whooper Swan is to conserve and restore the key natural habitat and reduce the dependence of the swan on artificial food.
Literature type: Thesis
Language: English
Full reference: Mandila, J.M. 2015. Problems of translocation: case study Lesser White-fronted Goose. , B.Sc. Thesis. Faculty of Environment and Natural Resources, Freiburg, Germany.
Keywords: reintroduction, evaluation, translocation, thesis, Germany, Sweden
Abstract:
In order to prevent extinction of the endangered Fennoscandian Lesser White-fronted Goose (LWfG) population, several translocation attempts have been conducted since 1981. Reintroductions prior to 2010 were based on captive birds. By altering the species migration route, the birds were led from former breeding grounds of the Fennoscandian population to safer wintering grounds in Western Europe. The subsequent detection of introgression from other goose genes among the source population led to further releases being put on hold. However, hybridization may be a natural phenomena among LWfG, although research supporting such a view is scarce and the data used questionable, probably relying on samples from escapees. Furthermore, reintroduction by means of using a non traditional route has been criticised due to the change in habitat selection and feeding behaviour of the released population. More recently, releases have been carried out with pure bred LWfG using the traditional route to Western Europe. Although this supports the view that the migration route used is an earlier traditional one which got lost as a result of the decline in the Fennoscandian population, analysis of the supporting data shows that the evidence is too scarce to make such an assumption. Since reintroduction is threatening the wild LWfG genetically and ecologically due to the adoption of genetic traits and behaviour caused by inter-breeding with the released population, the restricted resources of suitable birds should be kept for possible future supplementation of the Fennoscandian population in accordance with the IUCN Guidelines. Furthermore, in order to maintain the wild population and lead to its recovery to a favourable conservation status, efforts should concentrate on the reduction of threats along the traditional migration route and the restoration of its natural habitats.
Literature type: Thesis
Language: English
Download:Full reference: Niemelä, M. 2009. Biotic interactions and vegetation management on coastal meadows. , Acta Universitatis Ouluensis. A Scientiae Rerum Naturalium 360. Faculty of Science, University of Oulu, Finland.
Keywords: cattle, coastal meadow, diet of geese, grazing, management, plant\ncompetition, plant parasitism, threatened species, vegetation succession, Finland, Bothnian Bay
Abstract:
Conservation of rare habitats and species are central elements in the management of semi-natural grasslands of high biodiversity. Understanding the impacts of various abiotic and biotic interactions and management methods on threatened species is fundamental to their conservation. In the present study, effects of competition, plant parasitism, grazing and mowing were studied at the community level in Bothnian Bay coastal meadows and in greenhouse. This was the first time when the impacts of various biotic interactions on the critically endangered creeping alkali grass (Puccinellia phryganodes) have been explored in detail in one of its rare occurrences in the boreal vegetation zone in Europe. In addition, questions related to ecological and economical sustainability of cattle grazing on coastal meadows were examined. Puccinellia phryganodes was found to suffer severely from competition with taller graminoids. Simulated and actual grazing by greylag goose, Anser anser, as well as infection by a hemiparasitic plant, Odontites litoralis, were found to indirectly benefit P. phryganodes by decreasing the competitive advantage of its competitors. In spite of the relatively intensive grazing by greylag goose in the field, P. phryganodes experienced a drastic decrease during four years in the grazed experimental quadrats and simultaneously the proportion of the taller graminoids increased substantially. Primary succession of coastal meadow vegetation was found to progress rapidly and continuous formation of suitable open habitats is therefore crucial for the subordinate species. Mowing was found to be an effective management method for some threatened plant species in coastal meadows, but not for P. phryganodes, which would probably benefit more, for example, from livestock grazing. Both lightly and rather intensively managed large open meadows could provide optimal habitats for the critically endangered lesser white fronted goose (Anser erythropus) as well as for the greylag goose. The relatively low and variable yield of the coastal meadow vegetation compared to that of cultivated grasslands sets limits how management by cattle grazing can be implemented. Key factors for both the biodiversity management and livestock production in coastal meadows are timing of the grazing season, intensity of grazing and selection of suitable types of animals.
Literature type: Thesis
Language: English
Download:Full reference: Ruokonen, M. 2001. Phylogeography and conservation genetics of the Lesser White-fronted Goose (Anser erythropus). , Acta Universitatis Ouluensis. A Scientiae Rerum Naturalium 360. Faculty of Science, University of Oulu, Finland.
Keywords: Anser, phylogeography, conservation genetics, mitochondrial control region
Abstract:
Analyses of mitochondrial control region sequences were used to infer phylogeny of Anser species, phylogeography of the lesser white-fronted goose, and genetic background of a captive stock. The genetic distances among the Anser species ranged from 0.9 to 5.5% in the complete control region sequences and supported the view of close relatedness of these species. Among the four most closely related species, the bean, pink-footed, white-fronted and lesser white-fronted goose, the branching order is uncertain. The short internal branches and low support for the branching order suggest that the species have diverged recently within short time-intervals. The mtDNA tree obtained is incongruent with the traditional view of the species relationships, but the reasons for this remain to be clarified. Two diverged mitochondrial lineages were found in the lesser white-fronted goose and a refugial origin was proposed. Basal haplotypes are geographically widespread and indicate a recent common ancestry for populations. The derived haplotypes are confined to singular breeding populations and suggest restrictions to the present female gene flow. A shift in the frequency of the mtDNA lineages approximately coincides with a migratory divide in the Taimyr Peninsula. Low mtDNA diversity and significant difference in the haplotype frequencies observed in Fennoscandian subpopulation suggested that it should be considered as a management unit. The fossil record was examined to gain additional information about the colonisation history of the species, but was found to be of limited use. The captive lesser white-fronted goose stock used for reintroduction/restocking was shown to be incompatible with the Fennoscandian wild population. Some captive individuals carried the mtDNA of the white-fronted goose suggesting a hybrid origin. Hybridisation has probably occurred during captive propagation, but to clarify further the extent of introgression, nuclear markers should be applied. The structure and evolution of the control region were studied by comparing complete avian sequences. Saturation was found to occur at pairwise divergences of 10% as shown for third codon positions of the mitochondrial genes previously. In pairwise comparisons of the control region and cytochrome b sequences, the rate of divergence varied among the lineages. Two conserved sequence blocks showed considerable sequence conservation when compared to mammalian sequences.
Literature type: Thesis
Language: Finnish (In Finnish)
Full reference: Lampila, P. 2000. Kiljuhani (Anser erythropus): esiintyminen, kannan tila ja suojelu. , Thesis Pro Gradu, Biologian laitus, Oulun Yliopisto. 50pp.
Keywords: Fennoscandia, population modelling, mortality, production, matrix, development
Literature type: Thesis
Language: Norwegian (In Norwegian)
Download:Full reference: Jacobsen, K. 2000. Effekt av dominans på kondisjonsoppbygging hos dverggås Anser erythropus før hekking. [Effect of dominance on body condition in the Lesser White-fronted Goose Anser erythropus before breeding.] , Bachelor's thesis, Telemark University College, 23pp.
Literature type: Thesis
Language: English
Download:Full reference: Friberg, U. 1997. Habitat selection of the Lesser White-fronted Goose Anser erythropus, during the breeding season in Northern Finland and Norway. , Examenarbete i ämnet skoglig zooekologi. Institutionen för skoglig zooekologi. 1997: 4. Sveriges Lantbruk.
Keywords: habitat
Literature type: Thesis
Language: NA
Download:Full reference: Martynov, A.S. 1983. [Waterfowl of the Krasnoyarsk Territory: an essay of a cadaster evaluation.] , Biol. Doct. Thes. Moscow. 17pp.
Keywords: distribution
Number of results: 10