The fate of bats under climate change and habitat fragmentation

Bats represent one of the most understudied taxa of mammals.  As pollinators, seed dispersers and pest controllers, bats provide essential ecosystem services and represent a unique group of nocturnal species.  Several recent studies show that species assemblages of bats are likely to shift under the combined threat of climate change and habitat fragmentation, particularly in tropical regions.  Keeping bats connected through both climate refugia and formally protected lands that will remain suitable under climate change will be a key strategy to maintaining biodiversity in the future.

Deforestation in BrazilOver 80 species of bats inhabit Carajás National Forest, part of the Amazon deforestation arc in northcentral Brazil.  Future temperatures there may increase up to 6˚C by 2070, and designating protected areas will be critical to counteracting both climate change and anthropogenic disturbance.

A new study shows that over half of the species occurring in Carajás will potentially not find suitable habitats in the future, which could lead to a decline in ecosystem services.  A key conservation strategy will be maintaining connectivity between the National Forest and other protected areas that surround it.

 

Bats make‐up to 26% of Mexico’s mammalian fauna.  A recent assessment evaluates the future consequences of both land use and climate change across the country.  It reveals that at least half of the Mexican bat species will likely lose environmental suitability across their ranges, regardless of socio-economic development scenario.

Although bats can migrate long distances, the combined threats will make movement more challenging and necessitate management actions that protect against both shifts in habitat suitability and changes in landscape composition and connectivity.

 

 

Almost 100 species of bats inhabit the Caatinga, the largest tract of tropical dry forest in Brazil that has high biodiversity but has been poorly studied.  Climate change, habitat loss, and low protection threaten bat species richness.

A new synthesis of bat occurrence data and climate change projections reveals that these threats will continue to negatively affect species, probably across the board.  With less than 1% of the area with the highest potential of species occurrence currently in parks and reserves, conservation in the Caatinga should focus on increasing protected areas and keeping them connected.

 

Tea plantation in IndiaBats in the Western Ghats of India – a global biodiversity hotspot – are subjected to a matrix of agricultural lands and high human population.  A comparison of survey methods highlights the fact that tea plantations in the region contain a much lower species diversity of bats than protected forests, forest fragments, and shade coffee plantations.

However, tea plantations can improve bat diversity by leaving an undeveloped riparian corridor near rivers.  Reforestation work that includes the creation of riparian corridors would benefit bats as well as other wildlife such as endemic birds and elephants.

Resources

Costa, W.F., Ribeiro, M., Saraiva, A.M., Imperatriz-Fonseca, V.L. and Giannini, T.C. 2018. Bat diversity in Carajás National Forest (Eastern Amazon) and potential impacts on ecosystem services under climate change. Biological Conservation 218: 200-210.

da Silva, U.B.T., Delgado-Jaramillo, M., de Souza Aguiar, L.M. and Bernard, E. 2018. Species richness, geographic distribution, pressures, and threats to bats in the Caatinga drylands of Brazil. Biological Conservation 221: 312-322.

Wordley, C.F., Sankaran, M., Mudappa, D. and Altringham, J.D. 2018. Heard but not seen: Comparing bat assemblages and study methods in a mosaic landscape in the Western Ghats of India. Ecology and Evolution 8: 3883-3894.

Zamora‐Gutierrez, V., Pearson, R.G., Green, R.E. and Jones, K.E. 2018. Forecasting the combined effects of climate and land use change on Mexican bats. Diversity and Distributions. DOI: 10.1111/ddi.12686.

The role of a biological corridor in maintaining genetic connectivity of fruit bats (August 2017)

Coffee, tea, and their influence on bats in the Ghats (June 2017)

Protecting the path for bats through Brazil’s largest savannah (March 2016)

2018-06-01T10:43:55+00:00 May 30th, 2018|

About the Author:

Heather Cayton
Heather Cayton is the Managing Director of ConservationCorridor.org and a Research Assistant at Michigan State University. She received her B.S. from the University of Virginia and her M.S. from Virginia Tech, and has spent the past nine years studying corridors and rare butterflies in North Carolina.