Browsing by Subject "metapopulation dynamics"

Sort by: Order: Results:

Now showing items 1-6 of 6
  • Siren, Jukka; Lens, Luc; Cousseau, Laurence; Ovaskainen, Otso (2018)
    1. Individual-based models (IBMs) allow realistic and flexible modelling of ecological systems, but their parameterization with empirical data is statistically and computationally challenging. Approximate Bayesian computation (ABC) has been proposed as an efficient approach for inference with IBMs, but its applicability to data on natural populations has not been yet fully explored. 2. We construct an IBM for the metapopulation dynamics of a species inhabiting a fragmented patch network, and develop an ABC method for parameterization of the model. We consider several scenarios of data availability from count data to combination of mark-recapture and genetic data. We analyse both simulated and real data on white-starred robin (Pogonocichla stellata), a passerine bird living in montane forest environment in Kenya, and assess how the amount and type of data affect the estimates of model parameters and indicators of population state. 3. The indicators of the population state could be reliably estimated using the ABC method, but full parameterization was not achieved due to strong posterior correlations between model parameters. While the combination of the data types did not provide more accurate estimates for most of the indicators of population state or model parameters than the most informative data type (ringing data or genetic data) alone, the combined data allowed robust simultaneous estimation of all unknown quantities. 4. Our results show that ABC methods provide a powerful and flexible technique forparameterizing complex IBMs with multiple data sources, and assessing the dynamics of the population in a robust manner.
  • Kotze, D.J.; Niemelä, J.; Nieminen, M. (Blackwell, 2000)
  • Fountain, Toby; Duvaux, Ludovic; Horsburgh, Gavin; Reinhardt, Klaus; Butlin, Roger K. (2014)
  • Fabritius, Henna; Jokinen, Ari; Cabeza, Mar (2017)
    Species living in metapopulations depend on connected habitat networks for their survival. If habitat networks experience fast temporal dynamics, species conservation requires preventing habitat discontinuities that could lead to metapopulation extinctions. However, few institutional solutions exist for the maintenance of spatiotemporally dynamic habitat networks outside of protected areas. To explore this often neglected problem, we studied the institutional fit of false heath fritillary (Melitaea diamina) conservation in Finland from the perspective of conservation institutions' ability to manage early successional habitat availability for this endangered species. We identified four institutional arrangements that enable effective conservation management of dynamic habitat networks: (1) acknowledgment of habitat dynamics, (2) monitoring of and responding to changes in the habitat network, (3) management of resources for fluctuating resource needs, and (4) scaling of activities through flexible collaborations. These arrangements provide the institutional flexibility needed for responding to temporal changes in habitat availability.
  • Fountain, Toby; Butlin, Roger K.; Reinhardt, Klaus; Otti, Oliver (2015)
    In some species, populations with few founding individuals can be resilient to extreme inbreeding. Inbreeding seems to be the norm in the common bed bug, Cimex lectularius, a flightless insect that, nevertheless, can reach large deme sizes and persist successfully. However, bed bugs can also be dispersed passively by humans, exposing inbred populations to gene flow from genetically distant populations. The introduction of genetic variation through this outbreeding could lead to increased fitness (heterosis) or be costly by causing a loss of local adaptation or exposing genetic incompatibility between populations (outbreeding depression). Here, we addressed how inbreeding within demes and outbreeding between distant populations impact fitness over two generations in this re-emerging public health pest. We compared fitness traits of families that were inbred (mimicking reproduction following a founder event) or outbred (mimicking reproduction following a gene flow event). We found that outbreeding led to increased starvation resistance compared to inbred families, but this benefit was lost after two generations of outbreeding. No other fitness benefits of outbreeding were observed in either generation, including no differences in fecundity between the two treatments. Resilience to inbreeding is likely to result from the history of small founder events in the bed bug. Outbreeding benefits may only be detectable under stress and when heterozygosity is maximized without disruption of coadaptation. We discuss the consequences of these results both in terms of inbreeding and outbreeding in populations with genetic and spatial structuring, as well as for the recent resurgence of bed bug populations.
  • van Bergen, Erik; Dallas, Tad; DiLeo, Michelle F.; Kahilainen, Aapo; Mattila, Anniina L. K.; Luoto, Miska; Saastamoinen, Marjo (2020)
    Abstract The ecological impacts of extreme climatic events on population dynamics and/or community composition are profound and predominantly negative. Here, using extensive data of an ecological model system, we test whether predictions from ecological models remain robust when environmental conditions are outside the bounds of observation. First, we report a 10-fold demographic decline of the Glanville fritillary butterfly metapopulation on the Åland islands (Finland). Next, using climatic and satellite data we show that the summer of 2018 was an anomaly in terms of water balance and vegetation productivity indices across the habitats of the butterfly, and demonstrate that population growth rates are strongly associated with spatio-temporal variation in climatic water balance. Finally, we demonstrate that covariates that have previously been identified to impact the extinction probability of local populations in this system are less informative when populations are exposed to (severe) drought during the summer months. Our results highlight the unpredictable responses of natural populations to extreme climatic events. Article impact statement: A demographic crash of an iconic metapopulation reveals that extreme climatic events reduce the value of predictive models. This article is protected by copyright. All rights reserved