Details zur Publikation
|Titel (primär)||A model-derived short-term estimation method of effective size for small populations with overlapping generations|
|Autor||Grimm, A.; Gruber, B.; Hoehn, M.; Enders, K.; Henle, K.|
|Journal / Serie||Methods in Ecology and Evolution|
|Keywords||annual effective size; life-history parameters; Gehyra variegata; individual-based modelling; heterozygosity; overlapping generations; population demography; R-package NEff|
|Abstract||1.If not actively managed, small and isolated
populations lose their genetic variability and the inbreeding rate
increases. Combined, these factors limit the ability of populations to
adapt to environmental changes, increasing their risk of extinction. The
effective population size (Ne) is proportional to the loss
of genetic diversity and therefore of considerable conservation
relevance. However, estimators of Ne that account for
demographic parameters in species with overlapping generations require
sampling of populations across generations, which is often not feasible
in long-lived species.
2.We created an individual-based model that allows calculation of Ne based on demographic parameters that can be obtained in a time period much shorter than a generation. It can be adapted to every life-history parameter combination. The model is freely available as an R-package NEff.
3.The model was first used in a simulation experiment observing changes in Ne in response to different degrees of generational overlap. Results showed that increased generational overlap slowed annual rates of heterozygosity loss, resulting in higher annual effective sizes (Ny) but decreased Ne per generation. Adding the effect of different recruitment rates only affected Ne for populations with low generational overlap.
4.The model was further tested using real population data of the Australian arboreal gecko Gehyra variegata. Simulation results were compared to genetic analyses and matched estimates of the real population very well.
5.Unlike other estimation methods of Ne, NEff neither requires long time series of population monitoring nor genetic analyses of changes in gene frequencies. Thus, it seems to be the first method for calculating Ne within short time periods and comparably low costs facilitating the use of Ne in applied conservation and management.
|Grimm, A., Gruber, B., Hoehn, M., Enders, K., Henle, K. (2016):
A model-derived short-term estimation method of effective size for small populations with overlapping generations
Methods Ecol. Evol. 7 (6), 734 - 743