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uk/0/ Version: Accepted Version Article: Pereira, H, Ziv, G and Miranda, M (0) The countryside species-area relationship is a valid alternative to the matrix-calibrated species-area model., (). -.

1 This is a repository copy of The countryside species-area relationship is a valid alternative to the matrix-calibrated species-area model. White Rose Research Online URL for this paper: Version: Accepted Version Article: Pereira, H, Ziv, G and Miranda, M (0) The countryside species-area relationship is a valid alternative to the matrix-calibrated species-area model., (). -. ISSN 0- Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section of the Copyright, Designs and Patents Act allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version - refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher s website. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by ing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. eprints@whiterose.ac.uk

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3 Page of 0 0 Landuse change remains a major driver of biodiversity loss and projecting extinction rates for different scenarios of habitat conversion is a key concern in conservation research (Wright 00; Pereira et al. 00; de Baan et al. 0). Speciesarea relationships have been one of the main models used to develop such projections, but they have been recently criticized for overestimating extinctions (He & Hubbell 0). One problem is that classic projections assume that all natural habitats converted to humandominated habitats, such as agriculture and forestry, become completely hostile to biodiversity. However, there has been a growing recognition that many species are not constrained to native habitat fragments, and that the matrix habitats can play an important role in the conservation of biodiversity (Prugh et al. 00; Karp et al. 0). Recently a comparison of two models that incorporate the wider landscape context, the countryside SAR (Pereira & Daily 00) and the matrix calibrated SAR (Koh & Ghazoul 00), has been done by Koh and Ghazoul (00). Here we show that that the results of that comparison are incorrect, and that in contrast with their results, the countryside SAR outperforms both the matrix calibrated SAR and classic SAR projections in projecting tropical bird extinctions. The countryside SAR classifies species into functional groups with particular affinities for different habitats in the landscapes. The richness of each functional group is given by () where is the affinity of functional group to habitat, is the area of habitat in the landscape, is the number of habitat types, and and are the usual parameters of the classic speciesarea relationship. The affinities can be interpreted as the proportion of area of habitat that is usable by functional group, so that 0. 0 Consider now a landscape that was originally covered by native habitat only, which we name habitat. Assuming a single functional group (i.e. dropping the subscript in Eq. ), the proportion of species remaining after habitat conversion is where is the original area of native habitat, is the area of habitat after conversion, is the new number of species in the landscape, and is the original number of species. Note that the original area of native habitat equals the sum of the new areas of all habitats,. Furthermore, we assume that species have maximum affinity for the native habitat,. Koh and Ghazoul (00) proposed instead the matrixcalibrated SAR, which gives the proportion of species remaining as () #!$%! "! ()

4 Page of 0 where is the proportional area of habitat relative to the total converted area (the area of the matrix), & '! ()*,-. ' + /'+ ()*, and 0 is the sensitivity of the taxon to the transformed habitat. In order to compare the performance of different speciesarea models in projecting species extinctions, Koh and Ghazoul (00) look at birds in 0 biodiversity hotspots in the world. For each hotspot they estimate the proportion of native habitat remaining and the proportion that has been converted into each of three humandominated habitats: disturbed forest, agricultural land and urban area. They estimate extinctions as all endemic bird species to each hotspot that have been classified as extinct, critically endangered, endangered or vulnerable by IUCN, assuming that threatened species would become extinct in the future when species richness would reach an equilibrium with the amount of available habitat. Next they estimate the sensitivities 0 and affinities using a database of studies of how many species disappear locally when natural habitat is converted to each of the humandominated habitats. For the countryside SAR, the affinity for habitat can be derived from such database using Eq. (), 0 () where we assume full habitat conversion ( 0 and. For the matrixcalibrated SAR, it is not possible to derive such an expression for full habitat conversion as Eq. () always tends to zero when 0. Instead Koh and Ghazoul (00) assume: 0 () This shows that affinities and sensitivities are related as 0. Unfortunately, in their paper, Koh and Ghazoul (00) calculate the affinities simply as 0, ignoring the exponent. Using this incorrect calculation of affinities they find that the best projections of endemic bird extinctions are made by the matrix model, followed by the classic SAR, and that the countryside SAR has the worst performance. We have recalculated the projections of extinction rates using the data from Koh and Ghazoul (00) and the same zvalue (0.), but the correct estimate of habitat affinities. We found that the countryside SAR outperforms both the matrixcalibrated SAR and the classic SAR in this dataset (Table, Figure ). 0 There might be other datasets where the matrixcalibrated SAR outperforms the countryside SAR, and more research is needed to compare the different SAR models. The countryside SAR is particularly suitable to describe diversity patterns in multi habitat landscapes even when the original habitat cover or species composition is not known. Recently, two studies have shown that the performance of the countryside SAR is better than the classic SAR in describing bird (Guilherme & Pereira 0) and plant (Proenca & Pereira 0) diversity in such landscapes.!"#"$ "%& ' "!"#"$

5 Page of German Centre for Integrative Biodiversity Research (idiv) HalleJenaLeipzig, Deutscher Platz e, 00 Leipzig. Germany, Institute of Biology, Martin Luther University Halle Wittenberg, Am Kirchtor, 00 Halle (Saale), Germany Centro de Biologia Ambiental, Faculdade de Ciências da Universidade de Lisboa, 0 Lisboa, Portugal School of Geography, University of Leeds, Leeds LS JT, United Kingdom 0 ( 0 0 De Baan, L., C. L. Mutel, M. Curran, S. Hellweg, and T. Koellner. 0. Land Use in Life Cycle Assessment: Global Characterization Factors Based on Regional and Global Potential Species Extinction. Environmental Science & Technology '): 0. Guilherme, J. L., and H. M. Pereira. 0. Adaptation of Bird Communities to Farmland Abandonment in a Mountain Landscape. PLoS ONE *:e. He, F., and S. P. Hubbell. 0. Speciesarea relationships always overestimate extinction rates from habitat loss. Nature ')$:. Karp, D. S., A. J. Rominger, J. Zook, J. Ranganathan, P. R. Ehrlich, and G. C. Daily. 0. Intensive agriculture erodes βdiversity at large scales. Ecology Letters!+: 0. Koh, L. P., and J. Ghazoul. 00. A MatrixCalibrated SpeciesArea Model for Predicting Biodiversity Losses Due to LandUse Change. Conservation Biology #': 00. Pereira, H. M. et al. 00. Scenarios for Global Biodiversity in the st Century. Science $$,: 0. Pereira, H. M., and G. C. Daily. 00. Modeling Biodiversity Dynamics in Countryside Landscapes. Ecology *):. Proenca, V., and H. M. Pereira. 0. Speciesarea models to assess biodiversity change in multihabitat landscapes: the importance of species habitat affinity. Basic and Applied Ecology!':0. Prugh, L., K. Hodges, A. Sinclair, and J. Brashares. 00. Effect of habitat area and isolation on fragmented animal populations. Proceedings of the National Academy of Sciences of the United States Of!,+:00 0. Wright, S. 00. The future of tropical forests. Year in Ecology and Conservation Biology 00!!-+:.

6 Page of!./0 " / / #,,.$+.00/%#,!,. Model ε² AIC wi (%) Evidence ratio Countryside SAR.,,,00 Matrix-calibrated SAR.,,, Classic SAR 0., 0,0!./0 /0 /#,.00/ %#,!,.

7 Page of Observed bird extinctions Madagascar Atlantic Forest Philippines Caribbean Sundaland Eastern Afromontane East Melanesian Islands Guinean Forests Mesoamerica Tumbes Chocó Magdalena Indo Burma Cerrado Horn of Western Africa Ghats and Sri Lanka New Madrean Caledonia Pine Oak Woodlands Coastal Forests Polynesia Micronesia Wallacea Tropical Andes Countryside SAR Matrix SAR Classic SAR Predicted bird extinctions

Chapter 14. Forest Fragmentation and Biodiversity

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