Biological Conservation 148 (2012) 1–18 Contents lists available at SciVerse ScienceDirect Biological Conservation journal homepage: www.elsevier.com/locate/biocon Review The effects of climate change on tropical birds ⇑ Çag˘an H. Sßekerciog˘lu a,b, , Richard B. Primack c, Janice Wormworth d a Department of Biology, University of Utah, 257 South, 1400 East, Salt Lake City, UT 84112-0840, USA b KuzeyDog˘a Derneg˘i, Ismail_ Aytemiz Cad., Istasyon_ Mah., 36200 Kars, Turkey c Biology Department, Boston University, Boston, MA 02215, USA d 6-16 St. Neot Ave., Potts Point, NSW 2011, Australia article info abstract Article history: Birds are among the most widely studied organisms on earth and represent an important indicator group Received 17 May 2011 for learning about the effects of climate change – particularly in regard to the effects of climate change on Received in revised form 12 October 2011 tropical ecosystems. In this review, we assess the potential impacts of climate change on tropical birds Accepted 17 October 2011 and discuss the factors that affect species’ ability to adapt and survive the impending alterations in hab- Available online 22 February 2012 itat availability. Tropical mountain birds, species without access to higher elevations, coastal forest birds, and restricted-range species are especially vulnerable. Some birds may be especially susceptible to Keywords: increased rainfall seasonality and to extreme weather events, such as heat waves, cold spells, and tropical Avian ecology cyclones. Birds that experience limited temperature variation and have low basal metabolic rates will be Biodiversity hotspots Climate change the most prone to the physiological effects of warming temperatures and heat waves. Mostly unknown Conservation species’ interactions, indirect effects, and synergies of climate change with other threats, such as habitat Deforestation loss, emerging diseases, invasive species, and hunting will exacerbate the effects of climate change on Endemism tropical birds. In some models habitat loss can increase bird extinctions caused by climate change by Evolution 50%. 3.5 °C surface warming by the year 2100 may result in 600–900 extinctions of land bird species, Global warming 89% of which occur in the tropics. Depending on the amount of future habitat loss, each degree of surface Ornithology warming could lead to approximately 100–500 additional bird extinctions. Protected areas will be more REDD important than ever, but they need to be designed with climate change in mind. Although 92% of Tropical biology currently protected areas are likely to become climatically unsuitable in a century, for example only 7 or 8 priority species’ preferred climatic envelopes are projected to be entirely lost from the African Important Bird Area network. Networks of protected areas need to incorporate extensive topographical diversity, cover wide elevational ranges, have high connectivity, and integrate human-dominated landscapes into conservation schemes. Most tropical bird species vulnerable to climate change are not currently considered threatened with extinction, often due to lack of knowledge; systematically and regularly gathering information on the ecology, and current and future distributions of these species is an urgent priority. Locally based, long-term tropical bird monitoring and conservation programs based on adaptive management are essential to help protect birds against climate change. Ó 2012 Published by Elsevier Ltd. Contents 1. Introduction . ........................................................................................................ 2 2. Geography, habitat and range shifts: which species will be most affected? . ............................................... 2 2.1. Montane species . ........................................................................................... 3 2.2. Species of tropical coastal and island ecosystems. ........................................................ 4 2.3. Birds in extensive lowland forests . ........................................................................... 4 2.4. Birds in non-forest habitats . ........................................................................... 4 2.5. Aquatic birds in the tropics . ........................................................................... 4 2.6. Arid zone species. ........................................................................................... 5 2.7. Birds in human-dominated landscapes . ........................................................................... 5 Abbreviations: BMR, basal metabolic rate; IBA, Important Bird Area; IPCC, Intergovernmental Panel on Climate Change; NPP, net primary productivity. ⇑ Corresponding author at: Department of Biology, University of Utah, 257 South, 1400 East, Salt Lake City, UT 84112-0840, USA. Tel.: +1 801 585 1052. E-mail address: [email protected] (Ç.H. Sßekerciog˘lu). 0006-3207/$ - see front matter Ó 2012 Published by Elsevier Ltd. doi:10.1016/j.biocon.2011.10.019 2 Ç.H. Sßekerciog˘lu et al. / Biological Conservation 148 (2012) 1–18 2.8. Projected impacts of range shifts on tropical birds. .............................................................. 5 2.9. Manakins: a case study. .............................................................................. 6 3. Evolution and adaptation: slow lives in a fast-paced new world . ..................................................... 6 3.1. How physiology and microclimate impact tropical bird species’ ability to adapt. ........................................... 7 3.2. Basal metabolic rate in tropical birds: implications for survival . ........................................... 8 4. Role of mobility and migration . ........................................................................................... 8 5. Interspecific interactions and indirect effects. ........................................................................ 9 5.1. Ecosystem functions and services . .............................................................................. 9 6. Destructive synergies: climate change exacerbates other environmental stressors. ................................. 10 6.1. Habitat loss . ................................................................................................ 10 6.2. Hunting . ................................................................................................ 10 6.3. Invasive species . ................................................................................................ 11 6.4. Emerging diseases and shifting disease vectors . ............................................................. 11 7. Seasonality and variability. .......................................................................................... 11 7.1. Extreme weather events . ............................................................................. 12 8. Discussion. .......................................................................................................... 12 8.1. Future projections and models . ............................................................................. 12 8.2. The need for more tropical research . ............................................................................. 13 8.3. The value of protected areas for tropical birds: planning for future change . .......................................... 13 8.4. Research and management. ............................................................................. 14 Acknowledgements . .......................................................................................... 14 References . .......................................................................................................... 14 1. Introduction With these in mind, we have conducted an extensive review of the literature on the effects of climate change on tropical birds. We Climate change is increasingly recognized, along with habitat searched the Web of Knowledge™ with the keywords climat⁄ AND destruction, as one of the most serious and widespread threats to chang⁄ AND bird⁄ and their variations. We focused on the studies biological diversity (IPCC, 2007). As scientists search for the best on tropical birds and also read the relevant articles cited in and cit- biological indicators of human-induced climate change, birds offer ing these articles. In a few cases, where tropical examples were not two advantages: first, they are the best-known class of organisms available, we gave temperate examples of phenomena that should when it comes to climate research (Wormworth and Sßekerciog˘lu, be watched for in tropical systems. Two of us (ÇHSß and JW) spent 2011), and second, millions of citizen-scientist birdwatchers the past two years reviewing and summarizing the literature on track them across the globe, contributing to extensive datasets climate change effects on birds for a recent book (Wormworth (Kinzelbach, 1995; www.ebird.org; www.worldbirds.org). For and Sßekerciog˘lu, 2011). example, the arrival dates of migratory birds feature prominently Our main goals are to outline the existing and potential effects in the long phenological records of Europe, in part thanks to natural- of climate change on tropical bird communities, to examine why ists like Robert Marsham who began compiling ‘Indications of certain bird species are more susceptible to climate change, and Spring’ in 1736 (Lehikoinen et al., 2004). to discuss how this information can be used to improve the conser- As a well-studied, globally-distributed indicator group, birds’