Limits...
Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape.

Pilliod DS, Arkle RS, Robertson JM, Murphy MA, Funk WC - Ecol Evol (2015)

Bottom Line: Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited.Many of these changes could have negative effects on remaining populations over the next 50-80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal.Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

View Article: PubMed Central - PubMed

Affiliation: U.S. Geological Survey Forest and Rangeland Ecosystem Science Center 970 Lusk Street Boise Idaho 83706.

ABSTRACT
Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900-1930), recent (1981-2010), and future (2071-2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May - September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50-80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

No MeSH data available.


Resistance distance (Ȓ) versus genetic distance (FST) for all pairwise combinations of 25 spotted frog populations in the northern Great Basin. Resistance distance values were derived from a Circuitscape model run in pairwise mode. Site pairs (open triangles; n = 600) are color‐coded to show different functions for each site. Overall model fit was xR2 = 0.68.
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ece31634-fig-0007: Resistance distance (Ȓ) versus genetic distance (FST) for all pairwise combinations of 25 spotted frog populations in the northern Great Basin. Resistance distance values were derived from a Circuitscape model run in pairwise mode. Site pairs (open triangles; n = 600) are color‐coded to show different functions for each site. Overall model fit was xR2 = 0.68.

Mentions: The validation connectivity model produced Ȓ values that were well correlated with FST values for 600 site pairs spanning the northern Great Basin (mean ± SE xR2 for 100 bootstrap runs = 0.68 ± 0.004). FOCALSITE was an important predictor, indicating that the relationship between Ȓ and FST was not identical for all sites (i.e., based on FST values, some sites were consistently more isolated than others for a given range of Ȓ; Fig. 7). FST increased rapidly to about 0.70 as Ȓ approached 800 and then leveled off. Once Ȓ exceeded approximately 800 (Fig. 7), a value that corresponded to an average Euclidian distance of approximately 200 km, genetic distance between sites ceased increasing. Ȓ explained more variability in FST than did Euclidian distance (mean ± SE xR2 for 100 bootstrap runs = 0.61 ± 0.007), despite a strong correlation between Ȓ and Euclidian distance (R2 = 0.90).


Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape.

Pilliod DS, Arkle RS, Robertson JM, Murphy MA, Funk WC - Ecol Evol (2015)

Resistance distance (Ȓ) versus genetic distance (FST) for all pairwise combinations of 25 spotted frog populations in the northern Great Basin. Resistance distance values were derived from a Circuitscape model run in pairwise mode. Site pairs (open triangles; n = 600) are color‐coded to show different functions for each site. Overall model fit was xR2 = 0.68.
© Copyright Policy - creativeCommonsBy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4588645&req=5

ece31634-fig-0007: Resistance distance (Ȓ) versus genetic distance (FST) for all pairwise combinations of 25 spotted frog populations in the northern Great Basin. Resistance distance values were derived from a Circuitscape model run in pairwise mode. Site pairs (open triangles; n = 600) are color‐coded to show different functions for each site. Overall model fit was xR2 = 0.68.
Mentions: The validation connectivity model produced Ȓ values that were well correlated with FST values for 600 site pairs spanning the northern Great Basin (mean ± SE xR2 for 100 bootstrap runs = 0.68 ± 0.004). FOCALSITE was an important predictor, indicating that the relationship between Ȓ and FST was not identical for all sites (i.e., based on FST values, some sites were consistently more isolated than others for a given range of Ȓ; Fig. 7). FST increased rapidly to about 0.70 as Ȓ approached 800 and then leveled off. Once Ȓ exceeded approximately 800 (Fig. 7), a value that corresponded to an average Euclidian distance of approximately 200 km, genetic distance between sites ceased increasing. Ȓ explained more variability in FST than did Euclidian distance (mean ± SE xR2 for 100 bootstrap runs = 0.61 ± 0.007), despite a strong correlation between Ȓ and Euclidian distance (R2 = 0.90).

Bottom Line: Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited.Many of these changes could have negative effects on remaining populations over the next 50-80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal.Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

View Article: PubMed Central - PubMed

Affiliation: U.S. Geological Survey Forest and Rangeland Ecosystem Science Center 970 Lusk Street Boise Idaho 83706.

ABSTRACT
Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900-1930), recent (1981-2010), and future (2071-2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May - September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50-80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

No MeSH data available.