Te rrestrial Ecoregions of the Wo rld: A New Map of Life on Earth

Transcription

1 Te rrestrial Ecoregions of the Wo rld: A New Map of Life on Earth DAVID M. OLSON, ERIC DINERSTEIN, ERIC D. WIKRAMANAYA K E, NEIL D. BURGESS, GEORGE V. N. POW E L L, EMMA C. UNDERWO O D, JENNIFER A. D AMICO, ILLANGA ITOUA, H O L LY E. STRAND, JOHN C. MORRISON, C O L B Y J. LOUCKS, THOMAS F. ALLNUTT, TAYLOR H. RICKETTS, Y U M I KO KURA, JOHN F. LAMOREUX, WESLEY W. W E T T E N G E L, PRASHANT HEDAO, AND KENNETH R. KASSEM The tapestry of life on Earth is unraveling as humans i n c re a s i n gly dom i n a te and tra n s form natu ral eco s ystem s. S c a rce re s o u rces and dwi n dling time force con s ervati onists to target their acti ons to stem the loss of bi od ivers i ty a pra gm a tic approach, given the high ly uneven distri buti on of s pecies and threats (Soulé and Kohm 1989, Ol s on and Di n ers tein 1998, Mace et al. 2000, Myers et al ).Un fortu n a tely, the abi l i ty to focus stra tegi c a ly is hindered by the abs en ce of a gl obal bi od ivers i ty map with su f f i c i ent bi ogeogra phic re s o luti on to acc u ra tely ref l ect the com p l ex d i s tri buti on of the Eart h s natu ral com mu n i ti e s. Wi t h o ut su ch a map, m a ny disti n ctive biotas remain unrecogn i zed. In this arti cl e, we ad d ress the dispari ty in re s o luti on bet ween maps curren t ly ava i l a ble for gl obal con s erva ti on planning and the re a l i ty of the Eart h s intri c a te patterns of l i fe. We h ave devel oped a det a i l ed map of the terre s trial ecoregi ons of the world that is bet ter su i ted to iden tify areas of o ut s t a n d- ing bi od ivers i ty and repre s en t a tive com mu n i ties (Noss 1992). We define ecoregi ons as rel a tively large units of land con t a i n i n g a disti n ct assem bl a ge of n a tu ral com mu n i ties and spec i e s,wi t h bo u n d a ries that approx i m a te the ori ginal ex tent of n a tu ra l com mu n i ties pri or to major land-use ch a n ge. Our ecoregi on map of fers fe a tu res that en h a n ce its uti l i ty for con s erva ti on planning at gl obal and regi onal scales: compreh en s ive covera ge,a cl a s s i f i c a ti on fra m ework that builds on ex i s ting bi ogeogra phic knowl ed ge, and a det a i l ed level of bi ogeogra phic re s o luti on. E coregi ons ref l ect the distri buti ons of a broad ra n ge of fauna and flora ac ross the en ti re p l a n et, f rom the vast Sa h a ra De s ert to the diminutive Cl i p- perton Island (eastern Pacific Oce a n ). Th ey are cl a s s i f i ed within a sys tem familiar to all bi o l ogi s t s bi ogeogra ph i c realms and bi om e s.e coregi on s, repre s en ting disti n ct bi o t a s (Dasmann 1973, 1974,Udva rdy 1975), a re nested within the bi omes and realms and, toget h er, these provi de a fra m ework for com p a ri s ons among units and the iden ti f i c a ti on of repre s en t a tive habitats and species assem bl a ge s. A N EW G LO BA L M A P O F T E R R E S T R I A L E C O R E G I O N S P ROV I D E S A N I N N OVAT I V E TOO L F O R C O N S E RV I N GB I O D I V E R S I T Y Al t h o u gh our ecoregi ons are inten ded pri m a ri ly as units for con s erva ti on acti on,t h ey are built on the fo u n d a ti ons of classical bi ogeogra phy and ref l ect ex ten s ive co ll a bora ti on with over 1000 bi ogeogra ph ers,t a xon om i s t s,con s erva ti on bio l ogi s t s,and eco l ogists from around the worl d.con s equ en t ly, ecoregi ons are likely to ref l ect the distri buti on of s pecies and com mu n i ties more acc u ra tely than do units based on gl ob a l and regi onal models derived from gross bi ophysical fe a tu re s, su ch as ra i n f a ll and tem pera tu re (Ho l d ri d ge 1967, Wa l ter and Box 1976, S chulz 1995, Ba i l ey 1998), veget a ti on stru ctu re (UNESCO 1969, de L a u ben fels 1975, S ch m i d t h ü s en 1976), or D avid Olson ( dav i d. o l s o w w f u s. o r Eric g ), Diners t e i n,eric Wikram a n aya ke, Neil Burgess, George Po we l l, Jennifer D Amico, H o l l y S t r a n d,john Morr i s o n,c o l by Loucks, Thomas Allnutt, John Lamoreux, We s l ey We t t e n g e l,and Kenneth Kassem are conservation scientists in the Conservation Science Program at Wo rld Wildlife Fund US, Wa s h- i n g t o n, DC Emma Underwood is a doctoral candidate in the Graduate Group in Ecology, I n f o rmation Center for the Env i r o n m e n t, U n i v e rsity of Californ i a,d av i s, CA Illanga Itoua is a conservation biologist, Le Pe c q, France. Taylor Ricketts is a postdoctoral researcher at the Center for Conservation Biology, D e p a rtment of Biological Sciences, Stanford Univers i t y, Palo Alto, C A Yu m i ko Kura is a conservation specialist with the Wo rld Resources Institute, Wa s h i n g t o n, DC Prashant Hedao is a c o n s e rvation GIS specialist with Environmental Systems Research I n s t i t u t e, I n c.,r e d l a n d s, CA American Institute of Biological Sciences November 2001 / Vol. 51 No. 11 BioScience 933

2 s pectral sign a tu res from rem o te - s ensing data (Def ries et al , Loveland and Belw a rd 1997). None of these other approaches em ph a s i zes the import a n ce of en demic gen era and families (high er taxa), d i s ti n ct assem bl a ges of s pec i e s,or the i m print of geo l ogical history, su ch as the strong influ en ce of past gl ac i a ti ons or Plei s tocene land bri d ge s,on the distri buti on of plants and animals. Ex i s ting maps of gl obal bi od ivers i ty have been inef fective planning tools because they divi de the Earth into ex trem ely coa rse bi od ivers i ty units. These units are typ i c a ly well beyon d the size of l a n d s c a pes tract a ble for de s i gning net works of con s erva ti on are a s, the largest of pro tected are a s, or the 50,000 km 2 t h reshold for re s tri cted - ra n ge species (Statters f i el d et al. 1998) that are of p a rticular con cern (Stu a rt Pimm [ Cen ter for Envi ron m ental Re s e a rch and Con s erva ti on,colu m bia Un ivers i ty, N Y ], pers onal com mu n i c a ti on, ). The avera ge size of our ecoregi ons is ro u gh ly 150,000 km 2 ( m edian 56,300 km 2 ),wh ereas the bi o tic provi n ces of Udva rdy (1975) have an approx i m a te mean of 740,000 km 2 ( m ed i a n 306,000 km 2 ) and the bi od ivers i ty hotspots of Myers et al. ( ), wh i ch repre s ent thre a ten ed regi ons with high concen tra ti ons of en demic spec i e s,h ave an approx i m a te mean of 787,760 km 2 ( m edian 324,000 km 2 ). We su b d ivi ded the terre s trial world into 14 bi omes and ei ght bi ogeogra phic realms (Figure 1). Ne s ted within these are 867 ecoregi ons (Figure 2). This is ro u gh ly a fo u rfold incre a s e in re s o luti on over that of the 198 bi o tic provi n ces of D a s m a n n (1974) and the 193 units of Udva rdy (1975). The incre a s ed re s o luti on is most app a rent in the tropics (bet ween the Tropics of Ca n cer and Ca pri corn) wh ere Dasmann (1974) and Udva rdy (1975) iden tify 115 and 117 units, re s pectively, com p a red Fi g u re 1. The eco regions are catego ri zed within 14 biomes and ei ght bi ogeographic rea l m s to faci l i t a te repre sen t a tion analyse s. with 463 found in the ecoregi on map. Bi od ivers i ty assessmen t s that em p l oy large bi o tic provi n ces or hotspots of ten fail to discern small er but high ly disti n ctive are a s,wh i ch may re sult in these areas receiving insu f f i c i ent con s erva ti on atten ti on.th e island of New Guinea is illu s tra tive. Dasmann and Udva rdy treat the island as a single unit,wh ereas the new terre s trial map d i s tinguishes 12 ecoregi on s :four lowland and four mon t a n e broadl e a f fore s t s, one alpine scrub ecoregi on along the central cord i ll era, a mangrove fore s t,a fre s hw a ter swamp fore s t, and a sava n n a gra s s l a n d,a ll with disti n ct biotas and eco l ogical con d i ti on s. The del i n ea tion of e co regi o n s We began by accepting the bi ogeogra phic realms of P i el o u (1979) and Udva rdy (1975) and mod i f ying the bi ome sys tem s of Di n ers tein et al. (1995) and Ri cketts et al. (1999) (Figure 1 ). We then con su l ted ex i s ting gl obal maps of f l ori s tic or zoogeogra phic provi n ces (e.g., R ü bel 1930, G l e a s on and Cron quist 1964, G ood 1964), gl obal and regi onal maps of units based on the distri buti on of s el ected groups of p l a n t s and animals (e.g.,ha gm ei er 1966), the worl d s bi o tic provi n ce maps (Dasmann 1973, ,Udva rdy 1975), and gl obal maps of broad veget a ti on types (e.g., UNESCO 1969, de L a u ben fel s 1975,Schmidthüsen 1976). These were useful for eva lu a ti n g the ex tent of realms and bi om e s,the first two ti ers in our hiera rchical cl a s s i f i c a ti on. We then iden ti f i ed publ i s h ed regi onal cl a s s i f i c a ti on sys tems to be used as a baseline for ecoregi on bo u n d a ri e s.data and con su l t a ti ons from regi onal ex pert s were also important for final ecoregi on del i n e a ti on s. The use of wi dely recogn i zed bi ogeogra phic maps as a basis for ecoregi ons en h a n ces the uti l i ty of the map as a planning tool in different regi on s. For ex a m p l e, Wh i te s (1983) phytogeogra phic regi ons serve as the basis for the ecoregi on s of the Af ro trop i c s. The Au s- tralian ecoregi ons are derived f rom Th ack w ay and Cre s s well s (1995) bi ogeogra phic regi ona l i z a ti on. Ne a rctic ecoregi on s a re ad a pted from the ecoregi on s ys tems of O m ernik (1995), G a llant et al. ( ),Wi ken et a l. ( ), and Rzedows k i ( ). A more diverse set of s o u rces was used for the Neo trop i c s, i n cluding habi t a t cl a s s i f i c a ti ons for Brazil from the In s ti tuto Bra s i l ero de Geografia Estatística (IBGE 1993), the veget a ti on maps of Hu ber and Al a rcon (1988) and Huber et al. (1995) for Ven e z u el a and Guya n a, and Ho l d ri d ge s (1977) life zones for Cen tra l Am eri c a.the we s tern Pa l e a rc- 934 BioScience November 2001 / Vol. 51 No. 11

3 Fi g u re 2. The map of terre s trial eco regions of the wo rld re cogn i zes 867 disti n ct units, rou gh ly a fou rfold increa se in bi ogeographic discri m i n a tion over that of the 193 units of Udva rdy (1975). Maps of fre s hwa ter and marine eco regions are similarly needed fo r co n serva tion pl a n n i n g. tic ecoregi ons (except Af rica) were devel oped in con cert wi t h the DMEER (2000) proj ect. The ecoregi ons of Russia are ad a pted from Ku rn aev (1990) and Is ach en ko and co ll e a g u e s ( 1988 ),Japan from Miyawaki (1975), China from the sys tem s devel oped by the Chinese Veget a ti on Map Com p i l a ti on Comm i t tee (1979) and the Ch a n g chun In s ti tute of G eogra phy and Chinese Ac ademy of S c i en ces (1990), and So ut hwest As i a f rom Zo h a ry (1973). The major divi s i ons for In do - Ma l aya n ecoregi ons are based on the Mac Ki n n on (1997) units that build upon Dasmann s and Udva rdy s bi o tic provi n ce s.a key to the terre s trial ecoregi ons of the world map (Figure 2), t h e s o u rces for ecoregi on s,technical de s c ri pti on s,and digital data a re ava i l a ble at the Web site w w w. wo rl dwi l dl i fe. o rg / ci sen ce. Most ex i s ting sys tems requ i red that units be aggrega ted or d ivi ded, or that bo u n d a ries be mod i f i ed, to ach i eve three goa l s : (1) match recogn i zed bi ogeogra phic divi s i ons inadequ a tely ref l ected in that sys tem, (2) ach i eve a similar level of bi ogeogra phic re s o luti on of u n i t s,and (3) match units and bo u n d a ries in ad jacent sys tem s,wh en nece s s a ry. Wh ere wi dely accepted bi ogeogra phic maps were unava i l a bl e, we rel i ed f i rst on landforms and second on veget a ti on to inform the bio tic divi s i on s. For ex a m p l e,m ontane and lowland habi t a t s su pport disti n ct bi o tic com mu n i ties and dy n a m i c s.these were s ep a ra ted wh ere they occ u rred over ex ten s ive are a s.det a i l ed veget a ti on maps were then con su l ted. Veget a ti on is an important proxy for both plants and invertebra te s,wh i ch toget h er con s ti tute the vast majori ty of s pec i e s.most invertebra te s,a n d to some ex tent vertebra te s,a re assoc i a ted with different plant com mu n i ti e s,p a rti c u l a rly wh ere ecocl i m a tic differen ces are s trong (e.g., tropical wet forest versus tropical dry fore s t ). The appropri a te del i n e a ti on of ecoregi ons was obvious in m a ny cases. The sand pine scrubs of cen tral Flori d a, for exa m p l e, su pport many en demic species and high er taxa, a n d one can con f i den t ly discern the disti n ctiveness of its biota as well as its geogra phic ex ten t.ot h er ecoregi ons requ i red cl o s er s c ruti ny to discern the influen ce of h i s toric events on pre s en t - d ay distri buti on s. For ex a m p l e,the ef fects of ch a n ge s in sea level and land bri d ges in the Philippines arch i pel a go du ring the Plei s tocene have resu l ted in several island ecoregi ons in close prox i m i ty harboring many unique taxa ( He a n ey 1986, ). Del i n- e a ti on of ecoregi ons va ri ed s l i gh t ly in boreal and po l a r h a bi t a t s,wh ere species assembl a ges are rel a tively hom ogen eous ac ross large regi on s. Thu s, dynamics and proce s s e s were em ph a s i zed, su ch as maj or va ri a ti ons in cl i m a te, f i re d i s tu rb a n ce regi m e s,and large vertebra te migra ti ons (Ri cket t s et al ). Th ree caveats are appropri a te for all bi ogeogra phic mapping approach e s.f i rs t, no single bi ogeogra phic fra m ework is optimal for all taxa. E coregi ons ref l ect the best com prom i s e for as many taxa as po s s i bl e.secon d, ecoregi on bo u n d a ri e s ra rely form abru pt ed ge s ; ra t h er, eco tones and mosaic habitats bound them. Th i rd,most ecoregi ons contain habitats that d i f fer from their assign ed bi om e. For ex a m p l e, ra i n fore s t ecoregi ons in Am a zonia of ten contain small ed a phic sava n- n a s.more det a i l ed bi ogeogra phic analyses should map the less dominant habitat types that occur within the larger ecoregi on s, and ecoregi on con s erva ti on stra tegies should ad d ress their requ i rem en t s. Eco regions as a tool for co n serva ti o n How can a map of the worl d s ecoregi ons con tri bute to cons erving bi od ivers i ty? Our ecoregi on map has alre ady been used as a bi ogeogra phic fra m ework to high l i ght those areas of t h e world that are most disti n ctive or have high repre s en t a ti on va lue and are therefore wort hy of gre a ter atten ti on (Ol s on and Di n ers tein 1998, Ri cketts et al , Wi k ra m a n aya ke et al ).E coregi ons were ra n ked by the disti n ctiveness of t h ei r bi od ivers i ty fe a tu re s s pecies en dem i s m,the ra ri ty of h i gh er t a x a, s pecies ri ch n e s s, u nu sual eco l ogical or evo luti on a ry ph en om en a, and gl obal ra ri ty of t h eir habitat type (e.g., Med i terra n e a n - cl i m a te woodlands and scrub and tem pera te ra i n fore s t s ).E coregi ons can also be ra n ked by threats to bi o- d ivers i ty, the status of t h eir natu ral habitats and spec i e s,a n d degree of pro tecti on (Di n ers tein et al ,Ol s on and Di n- ers tein 1998, Ri cketts et al ,Wi k ra m a n aya ke et al ). Using this fra m ework, bi o l ogists can examine one of t h e most intere s ting bi o l ogical probl em s : the con cord a n ce and m i s m a tches in patterns of ri chness and en demism for indic a tor taxa, of ten bi rds and mammals, u s ed in con s erva ti on priori ty set ting (Statters f i eld et al , Fon s eca et al , November 2001 / Vol.51 No. 11 BioScience 935

4 Mace et al ).As an illu s- tra ti on,p a t terns of ri chness and en demism by ecoregi on for the worl d s 4,600+ terre s trial mammal species reveal some major d i f feren ce s. The three ri ch e s t mammal assem bl a ges are in the n ort h ern In dochina su btrop i- cal fore s t s, the sout hwe s tern Am a zon moist fore s t s,and the cen tral Za m bezian miom bo woodlands (Figure 3), wh ere a s the ecoregi ons with the high e s t nu m ber of en demic mammals a re the Cen tral Ra n ge mon t a n e forests of New Gu i n e a,the Albertine Rift montane forests of Cen tral Af ri c a,and the Su l awe s i m ontane forests (Figure 4). Similar analyses for bi rd s,h erpetof a u n a,and vascular plants a re under way, to be incorpora ted into a database that can be con ti nu a ly improved as new data are acqu i red. This ecoregi on s pecies database wi ll comp l em ent em er ging gri d - b a s ed species datasets by providing ins i ghts into the bi ogeogra phic rel a ti onship among cells (Broo k s et al ). The ecoregi on map com p l em ents gl obal pri ori ty - s et ti n g a n a lys e s,su ch as Global 200 (Ol s on and Di n ers tein 1998) and Ho t s pots (Myers et al ),by providing an even finer level of re s o luti on to assess bi od ivers i ty fe a tu re s.for ex a m p l e,t h e 25 terre s trial hotspots iden ti f i ed by Myers et al. (2000) amalga m a te 414 of the 867 ecoregi ons of the worl d, and the 237 units of G l obal 200 contain 402 terre s trial ecoregi on s.on our m a p, the In do Bu rma hotspo t ( Mi t term ei er et al ,Myers et al. 2000) covers 37 terre s tri a l ecoregi ons and Global 200 s e a s tern Hi m a l ayan forests (Ols on and Di n ers tein 1998) encompass four terre s trial ecoregi on s. The ri ch mosaic of t h e m a p s ecoregi ons calls attenti on to the import a n ce of gl ob a l bi od ivers i ty, i n cluding those ecoregi ons that lie out s i de the s pec i e s - ri ch trop i c s. New ways of l ooking at bi o- d ivers i ty loss and gl ob a l t h re a t s f rom cl i m a te ch a n ge to oil ex p l ora ti on,m i n i n g, road devel opm en t, and loggi n g a re fac i l i t a ted by this det a i l ed map of ecoregi on s.cu rren t ly, a con s ortium of con s erva ti on orga n i z a ti on s, mu s eu m s, a n d Fi g u re 3. The rel a tive ri chness of terre s trial mammal spe cies by eco region is dep i cte d. Wa rm er col o rs den ote eco regions containing ri ch er assem bl a ge s. h erb a ria are using this base map to frame discussions with logging companies and wood produ ct ret a i l ers abo ut redu c i n g the loss of forest bi od ivers i ty. It is also being used as a stra tegic tool to determine con s erva ti on inve s tm ents for the Worl d Ba n k, the US Agency for In tern a ti onal Devel opm en t, t h e World Wi l dl i fe Fu n d,the World Re s o u rces In s ti tute, The Natu re Con s erva n c y, and several fo u n d a ti ons (Di n ers tein et al , Roca et al , Ol s on and Di n ers tein 1998). Con s erva ti on stra tegies that con s i der bi ogeogra phic units at the scale of ecoregi ons are ideal for pro tecting a full ra n ge of repre s en t a tive are a s, con s erving special el em en t s,and ensu ring the pers i s ten ce of pop u l a ti ons and eco l ogical proce s s e s, Fi g u re 4. The level of s pe cies en d emism for terre s trial mammals shows different pa t tern s than that of ri ch n e s s.wa rm er col o rs den ote eco regions containing more en d emic spe ci e s. 936 BioScience November 2001 / Vol.51 No. 11

5 p a rti c u l a rly those that requ i re the largest areas or are most sens i tive to anthropogenic altera ti ons (Noss et al ,Soulé and Terbor gh 1999, Groves et al , Margules and Pre s s ey ).Some of the most promising tools for de s i gning networks of con s erva ti on are a s gap analys i s, equ a l - a rea gri d a n a lys e s, com p l em en t a ri ty analys e s, and other re s erve sel ecti on algorithms (Ki e s ter et al ,Margules and Pre s s ey 2000, Wi lliams et al , ) wi ll be more robust if condu cted within the con text of bi o l ogi c a lly def i n ed units su ch as ecoregi on s,as the distri buti on of s pecies and com mu n i ti e s ra rely coi n c i des with po l i tical units. An ecoregi on pers pective can also help iden tify wh et h er con s erva ti on areas are redu n- dant or com p l em en t a ry ac ross po l i tical bo u n d a ri e s. E coregi ons approx i m a te the dynamic arena within wh i ch eco l ogical processes most stron gly interact (Orians 1993). This cri tical com pon ent of the ecoregi on con cept all ows us to expand the scope of f actors con s i dered in con s erva ti on planning to inclu de eco l ogical ph en om ena as well as distri buti on s of s pec i e s. Pre s erving the migra ti ons in East Af ri c a, l a r ge pred a tor prey interacti ons in the So uth Asian ju n gles (Jo s h i et al ),or su f f i c i ent forest cover in the Am a zon Basin to maintain ra i n f a l patterns requ i res con s erva ti on ef forts ac ro s s en ti re ecoregi on s. Fortu n a tely, con du cting con s erva ti on assessments wi t h i n the fra m ework of l a r ger bi ogeogra phic units is an approach that is gaining su pport in all of the major intern a ti onal cons erva ti on or ga n i z a ti ons and in many govern m ent agen c i e s ( Groves et al ,Jo h n s on et al ,Mi t term ei er et al , Ri cketts et al ). E coregi on - l evel stra tegies are receivi n g i n c re a s ed funding from major con s erva ti on don ors. Th i s growing interest of fers en co u ra gem ent that ecoregi on maps and analyses can hei gh ten aw a reness abo ut the urgency of bi o- d ivers i ty loss and play an important role in con s erving the extra ord i n a ry va ri ety of l i fe on Eart h. Ack n owl e d gm en t s We gre a t ly apprec i a te the thousand-plus regi onal ex pert s who provi ded inva lu a ble knowl ed ge and assistance in the devel opm ent of this map. We apprec i a te the su pport of t h e World Ba n k ; the Com m i s s i on for Envi ron m ental Cooperati on ; Comisión Nac i onal Pa ra el Con oc i m i en to y Uso de la Bi od ivers i d ad ; In s ti tuto Nac i onal de Estatísti c a,g eografia e In form á ti c a ;the US Agency for In tern a ti onal Devel opm en t ; the Di gital Map of Eu ropean Eco l ogical Regi ons work i n g gro u p ; the Eu ropean Un i on ; the Fitzpatri ck In s ti tute ; t h e Bi od ivers i ty Su pport Progra m ;the World Re s o u rces In s ti tute ; The Na tu re Con s erva n c y; and the World Wi l dl i fe Fund Network. We thank J. Le a pe, D. Wood, J. Ma rti n - Jon e s,g. Heml ey, A. Ca rro ll, R. Sayre, J. Sober ó n, E. I ñ i go, K. Red ford, J. Robi n s on, U. Bo h n, O. O s term a n n, P. Rega to, R. Th ack w ay, M.Mc Kn i gh t,m.taye, and T. Green for their su pport and experti s e.we thank A. Ba l m ford,s.p i m m,g.o ri a n s,l. Fa rl ey, S.O Con n or, and S. O s ofs ky for revi ewing earl i er drafts of t h i s p a per. We would also like to thank the Na ti onal Geogra ph i c Soc i ety, in co ll a bora ti on with World Wi l dl i fe Fu n d,wh i ch has provi ded 10 copies of the ecoregi on map and te ach er s guide s to all public and priva te sch ools in the Un i ted States to prom o te bi ogeogra phic literacy and a bet ter understanding of gl obal bi od ivers i ty. We are indebted to all of the indivi du a l s who hel ped devel op the World Wi l dl i fe Fu n d / Na ti onal Geogra phic Soc i ety / E nvi ron m ental Sys tems Re s e a rch In s ti tute, In c., edu c a ti onal Web site that uses this map to pre s ent patterns of bi od ivers i ty from around the world (w w w. wo rl d- wi l dl i fe. o rg / wi l dwo rl d). Ref eren ces ci te d Ba i l ey RG E coregi on s : The Eco s ys tem Geogra phy of O ceans and Con ti n en t s.new York :S pri n ger- Verl a g. 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Joshi A,Di n ers tein E, Smith D The Terai Arc :Ma n a ging ti gers and other wi l dl i fe as met a pop u l a ti on s.in Wi k ra m a n aya ke E, Di n ers tein E, Lo u ck s C, Ol s on D, Morri s on J, L a m oreux J, Mc Kn i ght M, Hedao P. Terre s tri a l E coregi ons of the In do - Pac i f i c :A Con s erva ti on As s e s s m en t.wa s h i n g ton ( DC ) : Island Pre s s. Ki e s ter A R,S cott JM, C suti B, Noss RF, But terf i eld B, Sahr K,Wh i te D Con s erva ti on pri ori ti z a ti on using gap data. Con s erva ti on Bi o l ogy 10: Ku rn aev S Forest Regi on a l i z a ti on of the USSR. Map 1:16,000,000. Mo s cow: Na ti onal Agency of G eodesy and Ca rtogra phy. 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