Rapid viability analysis for metapopulations in dynamic habitat networks

Abstract

For land-use planning, numerically fast and easily applicable tools are urgently needed that allow us to assess how landscape structure and dynamics affect biodiversity. To date, such tools exist only for static landscapes. We provide an analytical formula for the mean lifetime of species in fragmented and dynamic habitat networks where habitat patches may be destroyed and created elsewhere. The formula is able to consider both patch size heterogeneity and dynamics additionally to patch number and connectivity. It is validated through comparison with a dynamic and spatially explicit simulation model. It can be used for the optimization of spatio-temporal land-use patterns in real landscapes and for advancing our general understanding of key processes affecting the survival of species in fragmented heterogeneous dynamic landscapes.

Effects of species turnover on reserve site selection in a fragmented landscape

“…While higher representation targets will reduce the risk that a species will be completely lost from a network of sites, it does not remove the effect temporal variability in species data has on resulting reserve networks, at least in our landscape (our study). Moreover, currently no rules exist to decide how many representations are needed to reduce extinction risks to acceptable levels in dynamic systems (but see Drechsler and Johst 2010).…”

“…In order to overcome restrictions resulting from temporal variability, a final option could be to focus on fewer species as surrogates and to include information on metapopulation dynamics taken from occupancy data (Hanski 1999), from long-term census data (e.g., from the study of mosaic cycles: Kleyer et al 2007), or from rules of thumb for metapopulation viability (Frank 2004;Drechsler and Johst 2010) in the selection process (Nicholls 1998;Moilanen and Cabeza 2002). Note that the first two approaches may also result in biased information due to the confounding of sampling effects and true species turnover (Frank 2005;MacKenzie et al 2006).…”

The consequences of habitat fragmentation on disease propagation

“…More recently, more sophisticated migration mechanisms have been taken into account, such as density-dependent migrations [11] or evasion and pursuit strategies on the part of the populations inhabiting the partitioned environment [20]. The mean lifetime of a species in a network of patches which is dynamically changing has been established [10]. All these efforts tend to elucidate the importance of the impact that habitat fragmentation has on the dynamics of the populations living in the disturbed environment.…”

Offsetting Policies for Biodiversity Conservation

“…Populations of species living in these patchy landscapes can be described as metapopulations. The survival of species living in such landscapes can be evaluated by the mean metapopulation lifetime, that is, the time during which on average one or more habitat patches in the landscape are occupied by the species (Frank and Wissel, 2002;Drechsler, 2009;Drechsler and Johst, 2010). The survival of species living in such landscapes can be evaluated by the mean metapopulation lifetime, that is, the time during which on average one or more habitat patches in the landscape are occupied by the species (Frank and Wissel, 2002;Drechsler, 2009;Drechsler and Johst, 2010).…”

“…Thus, although the introduction of biodiversity offsetting into a landscape implies an increased habitat patch turnover, the total amount of habitat patches is maintained. Johst et al (2011) have demonstrated the usefulness of such a formula for the rapid and convenient assessment of trade-offs between different landscape attributes for a variety of dynamic landscapes and species (for general applicability and validity of the formula, see Drechsler and Johst, 2010). This makes a systematic exploration of trade-offs between landscape attributes cumbersome.…”