Limits...
The dual role of rivers in facilitating or hindering movements of the false heath fritillary butterfly.

Fabritius H, Rönkä K, Ovaskainen O - Mov Ecol (2015)

Bottom Line: The riparian population of the false heath fritillary did not show major differences to reference populations in terms of movement parameters within breeding habitat, high-quality matrix and low-quality matrix.An artificial riparian landscape mimicking those of the coastal distribution resulted into more directional, longitudinal movements both parallel and perpendicular to the river than a more mosaic-like landscape, but the existence of the river in the landscape reduced movements across the river.As such, they can be used to compare movement parameters across populations, to study the effects of management interventions to endangered species and to identify areas that have high sensitivity to individual movement.

View Article: PubMed Central - PubMed

Affiliation: Department of Biosciences, University of Helsinki, P.O. Box 65 (Viikinkaari 1), FI-00014 Helsinki, Finland.

ABSTRACT

Background: Species movement responses to landscape structures have been studied using a variety of methods, but movement research is still in need of simple methods that help predicting and comparing movements across structurally different landscapes. We demonstrate how habitat-specific movement models can be used to disentangle causes of differentiated movement patterns in structurally different landscapes and to predict movement patterns in altered and artificial landscapes. In our case study, we studied the role of riparian landscapes to the persistence of the endangered false heath fritillary butterfly (Melitaea diamina) in its newly discovered coastal distribution region in Finland. We compared the movement parameters of the riparian population to two reference populations by using capture-recapture data and habitat-specific diffusion modelling, and analysed the role of the river and riverbank buffer zones in facilitating or hindering false heath fritillary movement with movement simulations.

Results: The riparian population of the false heath fritillary did not show major differences to reference populations in terms of movement parameters within breeding habitat, high-quality matrix and low-quality matrix. However, movement simulations showed that the habitat-specific movement parameters estimated for the false heath fritillary can lead into markedly different movement patterns in structurally different landscapes. An artificial riparian landscape mimicking those of the coastal distribution resulted into more directional, longitudinal movements both parallel and perpendicular to the river than a more mosaic-like landscape, but the existence of the river in the landscape reduced movements across the river.

Conclusions: Our study demonstrates how habitat-specific movement models enable comparisons of movement patterns across structurally different real, altered and artificial landscapes. As such, they can be used to compare movement parameters across populations, to study the effects of management interventions to endangered species and to identify areas that have high sensitivity to individual movement. In our case study, the river is shown to perform a dual role for the movements of the riparian false heath fritillary population. Whereas the river acts as a moderate movement barrier for the false heath fritillary, the longitudinal configuration of riverbank habitats provides a means especially for the male false heath fritillaries to move across the landscape.

No MeSH data available.


Days between marking and last recapture in the riparian population in comparison to the predictions by the reference models. Black circles depict real riparian data; blue squares (red triangles) with continuous (dashed) error bars show the means and 95% credibility intervals of posterior predictive data simulated for the riparian landscape based on the parameters estimates of the reference population REF1 (REF2). The data are shown separately for males (panel A) and females (panel B).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4940950&req=5

Fig3: Days between marking and last recapture in the riparian population in comparison to the predictions by the reference models. Black circles depict real riparian data; blue squares (red triangles) with continuous (dashed) error bars show the means and 95% credibility intervals of posterior predictive data simulated for the riparian landscape based on the parameters estimates of the reference population REF1 (REF2). The data are shown separately for males (panel A) and females (panel B).

Mentions: False heath fritillary movement parameters proved similar across populations also when the riparian capture-recapture data was contrasted against data simulated for the riparian landscape based on the reference movement models (Figures 3 and 4, Table 4). Among the test statistics we used, the distribution of times between marking and last recapture (Figure 3) acts as a proxy for life-span, whereas the observed total movement distance (Figure 4) acts as a proxy for overall movement activity. The exception for the good fit between the riparian data and the predictions of the models parameterised by the reference populations is the number of females that were observed only during one day or which moved less than 50 m in total between marking and last recapture, which number was underestimated by the model predictions (Figures 3 and 4, Table 4).Figure 3


The dual role of rivers in facilitating or hindering movements of the false heath fritillary butterfly.

Fabritius H, Rönkä K, Ovaskainen O - Mov Ecol (2015)

Days between marking and last recapture in the riparian population in comparison to the predictions by the reference models. Black circles depict real riparian data; blue squares (red triangles) with continuous (dashed) error bars show the means and 95% credibility intervals of posterior predictive data simulated for the riparian landscape based on the parameters estimates of the reference population REF1 (REF2). The data are shown separately for males (panel A) and females (panel B).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4940950&req=5

Fig3: Days between marking and last recapture in the riparian population in comparison to the predictions by the reference models. Black circles depict real riparian data; blue squares (red triangles) with continuous (dashed) error bars show the means and 95% credibility intervals of posterior predictive data simulated for the riparian landscape based on the parameters estimates of the reference population REF1 (REF2). The data are shown separately for males (panel A) and females (panel B).
Mentions: False heath fritillary movement parameters proved similar across populations also when the riparian capture-recapture data was contrasted against data simulated for the riparian landscape based on the reference movement models (Figures 3 and 4, Table 4). Among the test statistics we used, the distribution of times between marking and last recapture (Figure 3) acts as a proxy for life-span, whereas the observed total movement distance (Figure 4) acts as a proxy for overall movement activity. The exception for the good fit between the riparian data and the predictions of the models parameterised by the reference populations is the number of females that were observed only during one day or which moved less than 50 m in total between marking and last recapture, which number was underestimated by the model predictions (Figures 3 and 4, Table 4).Figure 3

Bottom Line: The riparian population of the false heath fritillary did not show major differences to reference populations in terms of movement parameters within breeding habitat, high-quality matrix and low-quality matrix.An artificial riparian landscape mimicking those of the coastal distribution resulted into more directional, longitudinal movements both parallel and perpendicular to the river than a more mosaic-like landscape, but the existence of the river in the landscape reduced movements across the river.As such, they can be used to compare movement parameters across populations, to study the effects of management interventions to endangered species and to identify areas that have high sensitivity to individual movement.

View Article: PubMed Central - PubMed

Affiliation: Department of Biosciences, University of Helsinki, P.O. Box 65 (Viikinkaari 1), FI-00014 Helsinki, Finland.

ABSTRACT

Background: Species movement responses to landscape structures have been studied using a variety of methods, but movement research is still in need of simple methods that help predicting and comparing movements across structurally different landscapes. We demonstrate how habitat-specific movement models can be used to disentangle causes of differentiated movement patterns in structurally different landscapes and to predict movement patterns in altered and artificial landscapes. In our case study, we studied the role of riparian landscapes to the persistence of the endangered false heath fritillary butterfly (Melitaea diamina) in its newly discovered coastal distribution region in Finland. We compared the movement parameters of the riparian population to two reference populations by using capture-recapture data and habitat-specific diffusion modelling, and analysed the role of the river and riverbank buffer zones in facilitating or hindering false heath fritillary movement with movement simulations.

Results: The riparian population of the false heath fritillary did not show major differences to reference populations in terms of movement parameters within breeding habitat, high-quality matrix and low-quality matrix. However, movement simulations showed that the habitat-specific movement parameters estimated for the false heath fritillary can lead into markedly different movement patterns in structurally different landscapes. An artificial riparian landscape mimicking those of the coastal distribution resulted into more directional, longitudinal movements both parallel and perpendicular to the river than a more mosaic-like landscape, but the existence of the river in the landscape reduced movements across the river.

Conclusions: Our study demonstrates how habitat-specific movement models enable comparisons of movement patterns across structurally different real, altered and artificial landscapes. As such, they can be used to compare movement parameters across populations, to study the effects of management interventions to endangered species and to identify areas that have high sensitivity to individual movement. In our case study, the river is shown to perform a dual role for the movements of the riparian false heath fritillary population. Whereas the river acts as a moderate movement barrier for the false heath fritillary, the longitudinal configuration of riverbank habitats provides a means especially for the male false heath fritillaries to move across the landscape.

No MeSH data available.