| 1. |
- Höglund, Jacob, et al.
(författare)
-
Genetic structure among black grouse in Britain : implications for designing conservation units
- 2011
-
Ingår i: Animal Conservation. - : Wiley. - 1367-9430 .- 1469-1795. ; 14:4, s. 400-408
-
Tidskriftsartikel (refereegranskat)abstract
- Black grouse in Britain have faced contraction of their range and have declined in numbers during the recent decades. As such, the species is a conservation concern in the UK. In order to aid conservation decisions, the terms Evolutionary Significant Unit (ESU) and Management Unit (MU) have been proposed. An ESU is an independently evolving evolutionary lineage defined by being reciprocally monophyletic for mitochondrial alleles, and which is significantly different from other lineages with regard to nuclear alleles, whereas an MU is operationally defined by only the latter criterion. Using mitochondrial sequences and nuclear microsatellite loci, we failed to find evidence that British black grouse is an ESU. However, British black grouse are sufficiently different from continental black grouse both with respect to mitochondrial and nuclear data to regard them as a separate MU. Furthermore, we present genetic data which suggest that British black grouse presently occur in what are probably three demographically independent units (roughly corresponding to Wales, northern England/southern Scotland and northern Scotland), which are genetically differentiated. The two southern units (Wales and northern England/southern Scotland) have lower genetic diversity and show signs of having lost genetic variability
|
|
| 2. |
- Höglund, Jacob, et al.
(författare)
-
Genetic variability in European black grouse (Tetrao tetrix)
- 2007
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 8:1, s. 239-243
-
Tidskriftsartikel (refereegranskat)abstract
- We studied microsatellite genetic variation in 14 different geographic populations of black grouse (Tetrao tetrix) across the European range. Populations were grouped in three different fragmentation categories: isolated, contiguous and continuous, respectively. Genetic diversity, measured as observed heterozygosity (H O), expected heterozygosity (H E) and allelic richness, were lower in isolated populations as compared to the other two categories that did not differ amongst one another. These results imply that lowered genetic variability in black grouse populations is negatively affected by population isolation. Our results suggest that the connectivity of small and isolated populations in Western Europe should be improved or else these face an increased risk of extinction due to genetic and demographic stochasticity.
|
|
| 3. |
|
|
| 4. |
- Larsson, Jobs Karl, et al.
(författare)
-
Genetic impoverishment of the last Black grouse (Tetrao tetrix) population in the Netherlands
- 2008
-
Ingår i: Molecular Ecology. - 0962-1083 .- 1365-294X. ; 17:8, s. 1897-1904
-
Tidskriftsartikel (refereegranskat)abstract
- We have studied a small isolated population of black grouse (Tetrao tetrix) in the Netherlands to examine the impact of isolation and reduction in numbers on genetic diversity. We compared the genetic diversity in the last extant Dutch population with Dutch museum samples and three other black grouse populations (from England, Austria and Norway, respectively) representing isolated and continuous populations. We found significantly lower allelic richness, observed and expected heterozygosities in the present Dutch population compared to the continuous populations (Austria and Norway) and also to the historical Dutch population. However, using a bottleneck test on each population, signs of heterozygosity excess were only found in the likewise isolated English population despite that strong genetic drift was evident in the present Dutch population in comparison to the reference populations, as assessed both in pairwise F-ST and STRUCTURE analyses. Simulating the effect of a population reduction on the Dutch population from 1948 onwards, using census data and with the Dutch museum samples as a model for the genetic diversity in the initial population, revealed that the loss in number of alleles and observed heterozygosity was according to genetic drift expectations and within the standard error range of the present Dutch population. Thus, the effect of the strong decline in the number of grouse on genetic diversity was only detectable when using a reference from the past. The lack of evidence for a population reduction in the present Dutch population by using the program BOTTLENECK was attributed to a rapidly found new equilibrium as a consequence of a very small effective population size.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Larsson, Jobs Karl, 1972-
(författare)
-
Population Fragmentation and Genetic Variation in Grouse
- 2005
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- 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.
|
|
