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Jerubės (Tetrastes bonasia) populiacijų genetinės struktūros įvertinimas lietuvoje, naudojant mikrosatelitų molekulinius žymenis / Evaluation of genetic variation in a Hazel Grouse (Tetrastes bonasia) population in Lithuania using microsatellite markersTomaitė, Gintarė 13 August 2012 (has links)
Šiame darbe buvo tiriamas Lietuvoje gyvenančių jerubių genetinis variabilumas panaudojant mikrosatelitinių pradmenų analizės metodus. Pavyzdžiai buvo surinkti iš Rietavo savivaldybėje, Ukmergės, Trakų, Vilniaus, Šakių ir Telšių rajonuose esančių miškų. DNR buvo išskiriama iš neinvaziniu būdu surinktų pavyzdžių, iškritusių plunksnų bei surinktų ekskrementų. Kadangi specialių mikrosatelitinių pradmenų jerubių rūšiai dar nėra sukurta, šiame darbe buvo panaudotos trys žvyrėms (Lagopus lagopus) specifiški mikrosatelitinių lokusų pagausinimui skirti pradmenys. Buvo apskaičiuoti alelių, genotipų ir heterozigotiškumo dažniai, ir individai iš Ukmergės MU pasižymėjo žemu alelių dažniu ir aukštu homozigotų dažniu. Mitochondrinės DNR analizė parodė, kad tarp 12 Lietuvos populiacijai priklausančių jerubių sekų, net 8 buvo skirtingos ir dėl to priskirtinos 8 skirtingiems haplotipais. Mitochondrinės DNR sekų filogenetiniai ryšiai parodė, kad Lietuvos jerubių populiacijoje aptikti haplotipai formuoja dvi filogenetiškai tolimas šakas, tuo tarpu Lenkijos haplotipų įvairovė gerokai didesnė. Tikėtina, kad šiuos skirtumus labiausiai įtakoja nevienodi lyginamų imčių dydžiai. / Non-invasively collected samples of feathers and faeces of Hazel Grouse (Tetrastes bonasia) were collected in different parts of Lithuania and covered several local populations of Rietavas, Ukmergė, Trakai, Vilnius, Šakiai and Telšiai districts. Three primer pairs of microsatellite loci, designed for taxonomically related Red Grouse (Lagopus lagopus scoticus), were used to verify their suitability for evaluation of genetic structure. Allele and genotype frequencies as well as heterozygosity were calculated and individuals from Ukmergė showed low frequency of allele, and high in homozigosity. Mitochondrial DNA analysis showed that in 12 sequences from Lithuanian population, 8 of them were different and could be assigned to 8 different haplotypes. Neighbour joining tree showed that haplotypes in Lithuanian population forms two branches with high distance. While variability of Poland haplotypes, obtained from Gene Bank was bigger. That could be affected by different compared samples sizes.
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Relationship of Ruffed Grouse Home Range Size and Movement to Landscape Characteristics in Southwestern VirginiaFearer, Todd Matthew 11 June 1999 (has links)
I addressed the effects of landscape characteristics on ruffed grouse (Bonasa umbellus) home range size and movement, and examined grouse selection for specific landscape characteristics and cover types. Grouse home ranges and movement patterns derived from telemetry data gathered from fall 1996 through fall 1998 were overlaid onto a GIS database of Clinch Mtn. Wildlife Management Area, VA. This database was developed from GPS data and LANDSAT thematic mapping imagery (30 m pixel scale) and was composed of 22 cover types. Landscape metrics were calculated using FRAGSTATS/ARC, and multiple regression was used to relate changes in home range size and movement to these metrics. I used Wilcoxon signed-rank tests to compare the values of landscape metrics calculated for each home range to those calculated for the area encompassed by the home range plus a surrounding 300 m buffer. I used Wilcoxon rank-sum tests to compare the values of landscape metrics for the home ranges to the metrics calculated for 50 33 ha random plots. I used compositional analysis to test for preferential use of cover types.
I developed 2 regression models (P < 0.01) relating changes in home range size to landscape characteristics, 1 model (P = 0.09) relating the distance between seasonal home range centers to landscape characteristics, and 1 model (P = 0.03) relating average daily movement to landscape characteristics. Grouse home range size increased as patch shape became more irregular and patch size and the number of different cover types per hectare increased, and decreased as the amount of high contrast edge in the landscape increased. The distance between seasonal home range centers increased as Shannon's diversity index and the average distance between patches of similar cover types increased, and decreased as the amount of high contrast edge increased. Average daily movement increased as the average distance between patches of the same cover type increased and as the percent cover of a full (~75%) rhododendron and/or laurel understory within a grouse's home range increased, and decreased as the amount of high contrast edge in a bird's home range increased.
Ruffed grouse were selecting areas with high densities of smaller than average patches that were of uniform size and regular shape and contained higher than average amounts of high contrast edge. Areas containing a greater diversity of cover types than what was available in the study area also were preferred. Within these areas, clearcuts and mesic deciduous stands with a rhododendron/laurel understory were the most preferred cover types.
Creating and maintaining a landscape with high densities of small patches that are of uniform size and regular (square) shape would provide the highest quality ruffed grouse habitat in this region. Several of these patches should be early successional cover to provide an abundance of high contrast edge. Rhododendron and/or laurel thickets also may be beneficial as supplemental winter cover, and mesic stands of mature hardwoods should be well interspersed with these cover types to provide supplemental food sources. / Master of Science
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Population ecology of and the effects of hunting on ruffed grouse (Bonasa umbellus) in the southern and central AppalachiansDevers, Patrick Kevin 18 February 2005 (has links)
I investigated ruffed grouse (Bonasa umbellus) population ecology in the southern and central Appalachians as part of the Appalachian Cooperative Grouse Research Project (ACGRP). Several hypotheses have been offered to explain the low abundance of ruffed grouse in the region including inadequate quantity of early-successional forests due to changes in land use, additive harvest mortality, low productivity and recruitment, and nutritional stress. Through the cooperative nature of the ACGRP, researchers tracked >3,000 ruffed grouse between October 1996 and September 2002 and gathered data on reproduction, recruitment, survival, and mortality factors. As part of the ACGRP
My objectives were (1) estimate reproductive rates, (2) estimate survival and cause-specific mortality rates, (3) determine if ruffed grouse harvest in the Appalachian region is compensatory, and (4) estimate ruffed grouse finite population growth.
Ruffed grouse population dynamics in the Appalachian region differed greatly from the core of ruffed grouse range. In general, ruffed grouse in the Appalachian region had lower productivity and recruitment, but higher survival than reported for populations in the Great Lakes and southern Canada. However, within the southern and central Appalachian region, ruffed grouse population dynamics differed between oak-hickory and mixed-mesophytic forest associations. Productivity and recruitment were lower in oak-hickory forests, but adult survival was higher than in mixed-mesophytic forests. Furthermore, ruffed grouse productivity and recruitment were more strongly related to hard mast (i.e., acorn) production in oak-hickory forests than in mixed-mesophytic forests. The leading cause of ruffed grouse mortality was avian predation (44% of known mortalities). Harvest mortality accounted for only 12% of all known mortalities and appeared to be compensatory. Population models indicate ruffed grouse populations in the Appalachian region are declining, but estimates vary greatly stressing the need for improved understanding of annual productivity and recruitment. We posit ruffed grouse in the Appalachian region exhibit a clinal population structure and changes in life-history strategies due to gradual changes in the quality of food resources, changes in snow fall and accumulation patterns, and predator communities. Recommendations are presented for habitat and harvest management and future research and management needs. / Ph. D.
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Ruffed grouse (Bonasa umbellus) habitat ecology in the central and southern AppalachiansWhitaker, Darroch M. 15 January 2004 (has links)
Ruffed grouse populations are low in Appalachian forests, possibly because low habitat quality negatively affects survival, condition, and reproduction. Through the Appalachian Cooperative Grouse Research Project (ACGRP) researchers tracked >1500 radioed grouse at 10 study sites (1996__2002). To improve our understanding of Appalachian grouse habitat ecology, I carried out two primary analyses of this database. First, grouse should be under selective pressure to minimize movements, so I studied factors associated with variation in home range size. Second, importance of a habitat is affected by an individual's resource needs, and I investigated factors associated with variation in selection of "preferred" habitats. Both approaches yielded important insights into the species' regional habitat ecology.
As elsewhere, clearcuts, which afford escape cover, formed the cornerstone of grouse habitat in the region. However, a number of other factors were also important. At the root of this was a divergence in habitat ecology between grouse inhabiting the two major forest types in the region. In oak-hickory forests nutritional constraint strongly influenced habitat use. Grouse home ranges increased 2.5x following poor hard mast crops, and at these times grouse increased use of alternate foraging habitats. Grouse, especially females and broods, made extensive use of mesic bottomlands and forest edges, which in oak-hickory forests support relatively abundant soft mast and herbaceous forages. In contrast, grouse inhabiting mixed mesophytic forests were insensitive to hard mast, did not select bottomlands, reduced use of forest edges, and increased use of clearcuts. I feel that greater abundance of birch, cherry, and aspen, buds of which are a high quality winter food, relieves nutritional stress on grouse inhabiting mesophytic forests. A general inference was that grouse attempted to balance competing strategies of maximizing either survival or condition, and the expression of this tradeoff was mediated by forest composition.
Also presented here were studies of radiotelemetry error, roost site selection, and suitability of prescribed burning as a habitat improvement technique. In the closing chapter I make recommendations for managing Appalachian forests for grouse, which focus on improving winter foraging habitat, brood habitat, and escape cover, all of which are limiting in Appalachian forests. / Ph. D.
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Population Fragmentation and Genetic Variation in GrouseLarsson, Jobs Karl January 2005 (has links)
<p>In this thesis the genetic variation of two grouse species, the Chinese grouse (<i>Bonasa sewersowi</i>) and the Black grouse (<i>Tetrao tetrix</i>) was examined with neutral genetic markers: microsatellites. Habitat fragmentation and isolation leads to structuring among and loss of genetic variation within populations.</p><p>The Chinese grouse in a small population in Lianhuasan nature reserve was found to have undergone a population bottleneck and as a result of isolation and possible inbreeding showed genetic impoverishment hereof.</p><p>The Black grouse populations in Europe face various different conditions from widely distributed areas of suitable habitat in the northern and eastern parts of its range to highly naturally and anthropogenically fragmented habitat landscapes in the west.</p><p>Structure among populations was found in Great Britain where Wales, Scotland and England showed characteristics of three different genetic entities, indicating very little or no geneflow between these populations. </p><p>The Dutch population showed signs of loss of genetic variation as to be expected from a population that has historically decreased in population size from several thousands to tens of individuals in a matter of decades. However the possibility to spot signs of a bottleneck was impaired due to the short time-window in which this can be observed in a population with such a low effective population size (N<sub>E</sub>).</p><p>The sampled populations in Europe clustered into five different groups of genetic identities. The different clusters were: Great Britain-, the Netherlands-, Fenno-Scandian-, Alpine- and lowland German-Austrian populations. The level of genetic variation when compared over all these different populations decreased as a sign of isolation and small N<sub>E</sub>. However it was not feasible to separate the impact of these two factors.</p>
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Population Fragmentation and Genetic Variation in GrouseLarsson, Jobs Karl January 2005 (has links)
In this thesis the genetic variation of two grouse species, the Chinese grouse (Bonasa sewersowi) and the Black grouse (Tetrao tetrix) was examined with neutral genetic markers: microsatellites. Habitat fragmentation and isolation leads to structuring among and loss of genetic variation within populations. The Chinese grouse in a small population in Lianhuasan nature reserve was found to have undergone a population bottleneck and as a result of isolation and possible inbreeding showed genetic impoverishment hereof. The Black grouse populations in Europe face various different conditions from widely distributed areas of suitable habitat in the northern and eastern parts of its range to highly naturally and anthropogenically fragmented habitat landscapes in the west. Structure among populations was found in Great Britain where Wales, Scotland and England showed characteristics of three different genetic entities, indicating very little or no geneflow between these populations. The Dutch population showed signs of loss of genetic variation as to be expected from a population that has historically decreased in population size from several thousands to tens of individuals in a matter of decades. However the possibility to spot signs of a bottleneck was impaired due to the short time-window in which this can be observed in a population with such a low effective population size (NE). The sampled populations in Europe clustered into five different groups of genetic identities. The different clusters were: Great Britain-, the Netherlands-, Fenno-Scandian-, Alpine- and lowland German-Austrian populations. The level of genetic variation when compared over all these different populations decreased as a sign of isolation and small NE. However it was not feasible to separate the impact of these two factors.
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