Abstract

A noticeable fraction of the World's species inhabit disturbed or early-succession habitats. In Finland, 23.3 % of the endangered species are species of traditional agricultural biotopes or otherwise human-modified habitats. These habitats are, after forests, the second most important habitat for endangered species in Finland.

When conservation plans have to be designed for early-succession habitats and their species, specific complexities emerge due to their transitional nature. Protected areas are vulnerable to discontinuities in maintenance funding, and alternative strategies for site maintenance vary in terms of maintenance type, intensity and frequency. Besides the establishment of protected areas, species persistence may sometimes be better supported by altering the dynamics of transitional habitats or by establishing new habitat sites.

My thesis focuses on the challenges of conservation planning that are related to the maintenance of specific successional stages or disturbance frequencies in dynamically changing environments. My study species is an endangered butterfly, the false heath fritillary (Melitaea diamina), an endangered Finnish butterfly. The false heath fritillary has the status of a species of strict protection in Finland due to the rapid shrinkage of its distribution during the past decades. I have used the false heath fritillary and its habitats as a case study to develop methods to estimate habitat destruction rates, habitat maintenance effects and the spatial emergence pattern of dynamic habitats from field data. We use metapopulation models to study how changes in the patterns of patch emergence and destruction affect population viability and how habitat dynamics affect conservation success. Finally, we contrast our results against the institutional constraints in false heath fritillary conservation.

Our results show that false heath fritillary habitats, which occur on multiple land use types, have high destruction rates and reach their best quality 2-3 years since maintenance. In simulations, the habitat turnover rate and the spatio-temporal pattern of habitat patch emergence have a significant effect both on population viability and on the effectiveness of conservation actions. The institutional constraints of false heath fritillary conservation have led to unpredictability in habitat maintenance resourcing.

Conservation planning for early-successional species requires monitoring of habitat dynamics and prediction of changes in the future availability of habitat. The availability of site maintenance funding should be taken into account already during the conservation planning phase.

Published in

ISBN: 978-951-51-1587-4, eISBN: 978-951-51-1588-1
Publisher: University of Helsinki

UKÄ Subject classification

Ecology


Permanent link to this page (URI)

https://res.slu.se/id/publ/89694