Global Change Projections for Taiwan Island Birds: Linking Current and Future Distributions

Abstract

The earth is warming rapidly. Species around the world must adapt to the increasing heat and to the rapid rate of temperature change. Decision makers and managers must aid species to adapt and to keep up with the changes if they are not able to do so on their own. Special attention needs to be paid to small islands because they are at high risk for the loss of unique and threatened systems and species, and face habitat loss as a consequence of climate-induced rises in sea level. In this study, we examined 17 endemic avian species on the island of Taiwan. Bird observations from 1993 to 2004 were compared to modeled distributions for 2020, 2050, 2080 and 2100. We used 5 general circulation models (CCCMA, CCSR, EHAM4, GFDL, and HADCM3) for the Intergovernmental Panel for Climate Change A2 and B2 scenarios. Results show that the distributions of 15 out of 17 species are predicted to shift up in elevation with warming. As the lower distributional limits contract to higher elevation, the upper edge of their current distributions cannot shift up in elevation because they were already near or at the tops of the mountains. Consequently, their distributions are predicted to shrink over time. The median elevation of each of these species' distributions is higher than the median elevation of all available habitats on Taiwan. In addition, we find that a few common species are predicted to become rare species under climate change. Two of the 17 species examined are not near the tops of the mountains and are the only species that have median elevations of their distributions lower than the median of all available habitats on Taiwan. These 2 species are predicted to expand the upper-elevation distribution limit but not to contract the lower-elevational ReseARCh ARTICLe Launched to accelerate biodiversity conservationA peer-reviewed open-access journal Chia-Ying Ko et al. / Nature Conservation 2: 21-40 (2012) 22 limit, which results in a widening of their distributions. Hence, we suggest that the median elevation of a species' current distribution plays a key rule and can be further used as an index of the response birds most likely will exhibit as the temperature increases.

The potential effects of future climate change on suitable habitat for the Taiwan partridge (Arborophila crudigularis): an ensemble-based forecasting method

“…The changes in suitable habitat predicted by our study differ from the findings of Ko et al (2012), who predicted that suitable habitat for A. crudigularis would decrease under future climates. Several factors explain this difference.…”

“…The Taiwan partridge (Arborophila crudigularis) is a range-restricted bird that is endemic to the islands of Taiwan. Although the latest IUCN Red List (V 3.1) classified it in the Least Concern category (IUCN, 2015), learning about the potential effects of climate change on this species is still valuable for its conservation in the context of climate change, because A. crudigularis is a weak flier and cannot adapt to climate change quickly (Lu et al, 2012); the limited extent of the island does not provide enough opportunities for it to adjust to climate change by moving along latitudinal gradients (Chen et al, 2011); and its population trend is decreasing, and climate change may accelerate this process (Ko et al, 2012;IUCN, 2015).…”

Small‐scale species distribution model identifies restricted breeding habitat for an endemic island bird

“…In their review of over 2000 Maxent models, Bradie and Leung (2017) found that over 80% were conducted with a 1-km 2 resolution because climate data used in these models are typically also reported at 1-km 2 resolution (Hijmans et al, 2005). However, data collected at this scale have only a limited ability to capture potentially significant fine-scale habitat features that may be important for habitat selection (Ko et al, 2012;Latif et al, 2015). This largescale and coarse-resolution approach is especially unsuitable for species with small distributions or those species restricted to islands.…”