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Ecological Economics 68 (2009) 2051–2057
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Ecological Economics
j ourna l homepage: www.e lsev ie r.com/ locate /eco lecon
Analysis
Choosing the “cargo” for Noah's Ark – Applying Weitzman's approach to Borana cattlein East Africa
Kerstin K. Zander a,⁎, Adam G. Drucker a,b, Karin Holm-Müller c, Henner Simianer d
a School for Environmental Research, Charles Darwin University, Darwin NT 0909, Australiab Bioversity International, Maccarese, Rome, Italyc Institute for Food and Resource Economics, University of Bonn, Nussallee 21, 53115 Bonn, Germanyd Institute of Animal Breeding and Genetics, Georg-August-University Goettingen, Albrecht-Thaer-Weg 3, 37075 Goettingen, Germany
⁎ Corresponding author. School for EnvironmentaUniversity, Ellengowan Drive, Darwin NT 0900, Australi
E-mail address: [email protected] (K.K. Zan
0921-8009/$ – see front matter © 2009 Elsevier B.V. Adoi:10.1016/j.ecolecon.2009.01.011
a b s t r a c t
a r t i c l e i n f oArticle history:
If Noah had had the opportu Received 13 March 2008Received in revised form 20 October 2008Accepted 16 January 2009Available online 21 February 2009Keywords:Animal genetic resourcesCost-effectiveness analysisEthiopiaKenyaPrioritisation for conservation
nity to select the animals he took on board his Ark, he would have had to choosebetween many species, breeds and types within breeds, all containing different genetic material. How couldhe have made the right choice and which would he have taken on board given the constraints he had to face?Those trying to save threatened livestock breeds within a tight conservation budget face similar questions. Inthis paper we assess how different types of Borana cattle, a culturally significant breed in East Africa, mightbe prioritized for conservation. By applying a cost-effectiveness analysis on the basis of Weitzman's approachwe conclude that the highest priority should be given to the Ethiopian Borana type (EB) in Ethiopia. Noah,however, would also have been concerned about the problems of inbreeding and effective population size. Toovercome this problem we suggest that, rather than loading just two animals, he should have loaded onboard 1000 female and 100 male animals as a safe minimum. The minimum cost of conserving 1100 animalsof the EB type with the participation of Ethiopian communities is calculated to be €7700 per year, mostly inthe form of compensation payments to meet the opportunity costs of livestock-keepers that arise whenmaintaining the EB.
© 2009 Elsevier B.V. All rights reserved.
1. Introduction
Cattle are the species with the highest number of breeds reportedas extinct (209), comprising 16% of all recorded cattle breeds. A further16% are at risk and the status of another 30% is unknown. (FAO, 2007;p.37–39). Rege and Gibson (2003) note that a large proportion of theremaining cattle breeds are found in developing countrieswhere the riskof loss is highest. In particular, low-yielding indigenous livestock breedsare in jeopardy of becoming extinct as a result of changing productionsystems andmarket structures (Köhler-Rollefson, 2000), the trend beingtowards increased intensification and industrialization of productionsystems based on uniform genetic resources. With the decline oflivestock breeds a loss of farm animal genetic resources is inevitable.Their conservation deserves as much attention as those of wild animals.
The genetic resources of farm animals are public goods like those ofwild species but they also have a private good component. The publicgood character occurs, for instance, when pastures are held incommon and good breeding bulls become common property. Thegene pool of farm animals, conserved either on-farm or ex-situ, alsoconstitutes a public goodwith an option value for future use e.g. after adisease outbreak. Conserving important farm genetic resources hence
l Research, Charles Darwina.der).
ll rights reserved.
contributes to global biodiversity, as is the case for wild animals. Thusmost wild animals are only conserved for their option or existencevalues while farm animals provide both option values and use-valuesto those who keep and consume them.
Livestock breeds may be conserved for a number of other reasonsand research on setting conservation priorities abound, including onthe basis of option/insurance and cultural values (Simianer, 2005;Gandini and Villa, 2003), of ecological functions such as maintainingagro-ecosystems and landscapes (see, for example, Ostermann, 1998)and of diversity (see, for example, Rege et al., 2001). Conservation foroption/insurance purposes aims to maintain sufficient geneticdiversity to be able to adapt to future challenges, such as climatechange and new diseases, and focuses more on maintaining diversitywithin species than on single breed conservation. Assuming that itwill never be possible to fully maintain the current diversity of farmanimals, priority should be given to those breeds that contribute mostto present or expected future diversity (Simianer, 2005). By contrast,the conservation for cultural purposes favours the conservation ofspecific breeds in their present state, especially of those breeds whichhave a recognised cultural or ecological value.
One such breed is the Borana breed of east Africa. Previous studies(e.g. Coppock, 1994; Dolan, 1997; Haile Mariam et al., 1998; Zanderand Drucker, 2008) have shown that the Borana breed has a range offunctions and provides many valuable services to local livestock-keepers who strongly depend on this breed for their daily livelihoods
Fig. 1. Map of the research area. EB = Ethiopian Borana, KB = Kenyan Borana, OB =Orma Borana, SB = Somali Borana.
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in a pastoral production system. The value of its genetic material isalso recognised through its use in breeding and crossbreedingprogrammes in both developed and developing countries (Rege,1999; Simianer et al., 2003; FAO, 2008). There are four Borana types:three local types, the Ethiopian Borana (EB), the Orma Borana (OB),the Somali Borana (SB), and the improved type: the Kenyan Borana(KB) (ILRI, 2006; FAO, 2008). Insofar as it is unlikely that there will besufficient conservation investment to maintain all of them, a choicehas to be made with regard to prioritizing the conservation of themost “important” type.
1.1. Concepts and challenges of the Weitzman approach for farm animals
Pioneering work in the field of setting up priorities for diversityconservation was presented by Weitzman (1992, 1993) whoseapproach has become widely accepted as conceptional frameworkfor decision-making in conservation (Simianer, 2005). Weitzman'sapproach constitutes a cost-effectiveness methodology for themeasurement of the value of diversity in which distinctiveness isincluded as a utility function. His first theoretical work on theeconomics of biodiversity (1992) followed a practical example ofconservation of crane species (1993) and work on the Noah's ArkProblem (1998). Metrick and Weitzman (1998) consolidated theeconomic theoremwith data. The question thatWeitzman (1998) andMetrick and Weitzman (1998) attempted to solve was “which speciesto take on board Noah's Ark”, now known as the Noah's Ark Problem.The suggestion was that Noah should take species on board “in theorder of their gains in utility plus diversity, weighted by the increase intheir probability of survival, per dollar of cost” (Metrick and Weitz-man, 1998; p. 26).
Nonetheless, the Weitzman criterion has been criticised forholding only under very strict conditions. van der Heide et al.(2005) argued that the ecological and genetic implications of theWeitzman approach are not well defined given the assumption thatthe loss of a species usually has little or no effect on the existence ofother species (though see Zavaleta and Hulvey, 2004). They concludedthat the Weitzman formula in its initial form does not seem to besuitable for an analysis of which species to protect and through whichtypes of programme (van der Heide et al., 2005; p. 221). The authorsargued for the need to extend Weitzman's approach by consideringdistinctiveness, conservation costs, indirect utilities and survivalprobabilities. However, they in fact end up analysing/consideringonly the distinctiveness among the species in question, whileassuming all the other factors are identical.
Earlier, Simianer et al. (2003) had raised the importance of beingable to determine themaximumamount of livestock diversity that canbe conserved for a given input. Simianer (2002) and Simianer et al.(2003) focus on the contribution of a breed to overall genetic diversity,noting that utility is mainly associated with genetic distinctiveness(one of the components of Weitzman's theorem), while assuming thatthe economic values of each of the conserved breeds are identical.Weitzman's crane example (2003) follows a similar approach,focusing on extinction probabilities and the costs required to decreasethe extinction probability and thereby increase the survival rate of acrane species while setting proxies for the utility of cranes.
1.2. Objectives
As was space on the Ark, the resources available to conservethreatened farm genetic resources are limited. The Borana breed, abreast-hump type of the East African Shorthorned Zebu cattle (Payneand Hodges, 1997), is an example of a breed for which such choicesneed to be made. Unlike introduced breeds, the Borana breed hasgreat cultural meaning; without the Borana breed the traditionalpastoral lifestyle of the Borana people is likely to be undermined in thefuture if no incentives for conservation are generated. Similarly it is
unlikely that, without the Borana people and their traditionalcustoms, the breed could survive, as lack of indigenous knowledge(IK) prevents continuous breeding with Borana (Homann, 2004).Hence the Borana breed will remain as an essential aspect of asustainable animal production system only if conserved on-farm. Atthe same time its persistence will help maintain traditional socialstructures and continue to contribute to the food security for the ruralpoor in northern Kenya and southern Ethiopia.
This study applies a cost-effectiveness framework as a tool that canbe used to help set priorities for the conservation of the Borana breedbased on the maximum utility principle of the conserved type. Itdraws upon previous work by Weitzman (1998) [“Noah's Arkproblem”] and Simianer (2002, 2005) [“Noah's dilemma” and“Decision making in livestock conservation”]. Metrick and Weitzman(1998, p. 26) noted that it will not be easy in practice either to quantifythe four variables (distinctiveness, conservation costs, indirectutilities and survival probabilities) or to combine these variablesroutinely into a simple ranking formula. While, as shown in theprevious section, other scientists use proxies for the utility and costsand focus instead on molecular genetic analysis to specify geneticdistinctiveness between species or breeds, our research stands out byincluding economic values.
Further, while Weitzman's concept of Noah's Ark problem wasdeveloped for the preservation of biodiversity in general and firstapplied for wild species (Weitzman, 1993), it is not constrained to thespecies level and can be applied at individual, community orecosystem level (Weitzman, 1993; p. 160). We extended the conceptto the level of farm animal breeds/subtypes. We aim to show howtotal economic values (TEV) derived from stated preferences oflivestock-keepers can adequately be fitted into Weitzman's cost-effectiveness model.
A further objective is to shed light on the question of how manyanimals should be conserved once the priority subtype has beenidentified. The analysis is constrained to in-situ conservation inwhichindividuals of local communities are strongly involved, thus facilitat-ing the understanding of livestock-keepers' degrees of willingness to
2053K.K. Zander et al. / Ecological Economics 68 (2009) 2051–2057
participate in potential community-based conservation programmes.Finally, we calculate approximate gross costs for the relatedconservation programmes.
2. The research area and its cattle
Ethiopia is home to the largest cattle population in East Africa with29.5 million head, almost a third of the total East African cattlepopulation (ILRI, 2006). A further 12.5 million cattle are kept in Kenya(ILRI, 2006; FAO, 2008).
Borana cattle are herded by Borana-Oromyfa clans in southernEthiopia and northern Kenya. The Borana breed originated in SouthEthiopia and the neighbouring parts of Somalia and northern Kenya,and is now also being distributed over other areas of Africa. Accordingto theWorldWatch List (FAO, 2000) Borana cattle stocks can be foundin the Democratic Republic of Congo, Ethiopia, Kenya, Malawi,Somalia, Zambia, South Africa, Tanzania, Uganda, and, outside Africa,in Mexico and Australia. The distribution of the Borana subtypes keptin the research areas is shown in Fig. 1.
Although the population numbers provided indicate that the OBand EB (no records on the population size of the SB exist) are not atrisk (according toe the FAO/UNEP risk classification scheme; see FAO,2007), these numbers are not reliable for the research area. Accordingto DAGRIS (ILRI, 2006), in 1999 there were estimated to be1,896,000 EB cattle and 547,000 OB. Since the DAGRIS databank wascompiled in 1999 (ILRI, 2006), there has been immense crossbreedingof Borana cattle with other local and exotic breeds practised. Theserecords give an overview of all existing cattle in the Borana lowlandsbecause of the vague definition of a breed1 in this area and, apart fromherd books for the improved type of Borana on commercial ranches,the lack of pedigree information. These factors also make decisionsregarding conservation initiatives for the Borana cattle difficult.
Our observation is that most animals are crossbreds betweenBorana and other local breeds and often exotic breeds and few pureEB, SB and OB persist. From interview livestock-keepers consider theEB subtype to be the purebred, although genetic analyses is requiredto confirm this (Zander and Drucker, 2008). The crossbreeding withexotic and breeds is a major threat, suppressing the OB, SB and EB aswell as admixtures of them that have evolved over time and are nowalso important for the daily livelihoods of many livestock-keepers.Other main threats to this breed are the diminishing availability ofpastures as a result of population pressure, environmental changes(e.g. bush encroachment, more severe and more frequent drought)and changes in land use systems (from pastoralism to mixed farmingsystems), including from increased privatisation of both agriculturaland grazing land (Coppock, 1994; Hogg, 1997).
3. Methods and data
3.1. Applied method
Weitzman's suggested cost-effectiveness methodology for settingpriorities in biodiversity conservation can be written as follows(Weitzman, 1998):
Ri = Di + Ui½ � ΔPiCi
� �ð1Þ
where:
Ri = ranking value of breed iDi = distinctiveness of i=how unique or different is iUi = direct utility of i=howmuch a person likes or values i per se
1 The local breeds of cattle kept in the lowlands are named after the ethnic groupwhich introduced them. For example, there are Borana cattle, Arsi cattle, Guji cattleand Konso cattle, among others.
ΔPi = by how much can the survivability of i be improvedassuming that the conservation plan (the boarding on theArk) makes the breed safer
Ci = cost of improving the survivability of i
Weitzman assumed that the loss of biodiversity due to theextinction of a species is exactly equivalent to the distinctiveness ofthat species (Weitzman's criterion). Thismeans that the uniqueness ofeach species depends on the genetic distance Di between itself and itsnearest relative. Weitzman (1998) described Ri as “expected marginaldistinctiveness plus utility per dollar”, while van der Heide et al.(2005) used the term “performance index” for Ri. In this study Rirefers to ranking priorities that represent the conservation value ofBorana subtype i. The higher this value, the higher the subtype'spriority for receiving conservation support.
In the crane example, Weitzman emphasises genetic distances,stating that the diversity between species is the most decisive factorfor priority ranking. The author defines diversity as a measure ofdistinctiveness or dissimilarity (Weitzman, 1993; p. 159). In thiscontext, the Borana subtypewith the most genes unique to the Boranawould receive a higher rank. Unfortunately no molecular analysis ofthe Borana breed is available for the research area so geneticuniqueness of the subtypes is not known. Therefore, although thetraits local livestock-keepers value can be identified, we decided to setthe values for the genetic distinctiveness Di to zero for all the Boranasubtypes.
We define utility as the monetary value local livestock-keepersplace on the subtypes. We did not include any utility that peopleoutside the local Borana production system might derive from thesubtypes, including those who have benefited from cross-breeding. Assuch, the utilities used represent a lower-bound estimate.
3.1.1. The calculation of changes in survival probabilities (ΔPi)In Weitzman's crane example the survival probabilities are just
“best guesses” (Weitzman, 1993; p. 161), but not completely arbitrary.They are calculated based on a number of factors such as currentpopulation size, likely future trends, as well as to experts' opinionsabout the extinction probability of the different crane species. Wepartly use exogenous data, as did the study by Reist-Marti et al.(2003) on which our approach is based. Our chosen factors arethereby to some extent arbitrary but we believe that these are themost important ones affecting the survival and extinction probabilityof a breed. We also attempted to quantify the magnitude of thefactors by interviewing livestock-keepers using a Likert-scale apprai-sal. We aimed to assess the survival probability for every Boranasubtype and also for the other prevailing admixtures and local breedsin the research area. The applied scheme (see formula (2)), is takenfrom Reist-Marti et al. (2003) and we use it in such a way that thehigher the costs (Ci), i.e. the higher the investment into aconservation programme, the better is the change to change thesurvival probability of Borana subtypes. We hypothesise that for eachmonetary unit (Euros in this study) spent on the conservation of abreed/subtype, the probability that this breed survives increases. Wecalculated the ΔPi using the following formula (see also Reist-Martiet al., 2003):
ΔPi =X8n=1
zin + 0:1 ð2Þ
ΔPi values are computed as the sum of the scores of eight variablesdescribing each subtype/breed (Table 1). For each subtype the valuewas defined according to expert opinion, interviews with locallivestock-keepers, a literature review and the DAGRIS (ILRI, 2006)and DAD-IS (FAO, 2008) databanks. The variables that are used hereare specific to this study and were they to be applied to calculating ΔPi
Table 1Variables for the calculation of changes in survival probabilities.
Variable Values
1) Trend over the last 10 years (TR) 0.0=increasing0.05=stable0.1=decreasing
2) Distribution of breed (DI) 0.0=widespread over many countries0.05=widespread over East Africa0.1=localised only in the Boranalowlands
3) Livestock-keepers' attitude towardscrossbreeding (=Degree of indiscriminatecrossing (DC))
0.0=negative0.05=positive for crossbreeding withlocal breeds0.1=positive for crossbreeding withexotic and local breeds
4) Degree of risk of replacement by otherspecies (DS)
0.0=none0.05=slight0.1=high
5) Organisation of farmers (e.g. herdbook,farmer associations) (OR)
0.0=yes0.05=partial0.1=no
6) Existing conservation initiatives (CO) 0.0=yes0.05=partial0.1=no
7) Market access (MA) 0.0=high0.05=medium0.1=low
8) Awareness of risk of Borana breed (AR) 0.0=existing0.05=fairly existing0.1=non-existing
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of other species and breeds, the choice of the factors would need to bereviewed.
The range of values is the same for all variables and hence everyvariable has the same weighting factor. Rescaling to a value between0.1 and 0.9 was done to rule out the possibility that a breed may beconsidered completely safe due to a conservation programme orentirely doomed to extinction (see Reist-Marti et al., 2003) after therehad been investment in its conservation.
The higher ΔPi induced by a conservation programme for breed i,the higher the ranking position for a subtype/breed, i.e. the moreworthwhile it will be to invest in its conservation.
Table 2Distribution of interviewees in Ethiopia and Kenya.
Ethiopia
PA District
Yabello Arero Bule Hora Total
Didi Hara 100 – – 100Web – 97 – 97Wachile – 27 – 27Finchawa – – 22 22Total 100 124 22 246
Kenya
Location Zone
Central Marsabit Burbisa Total
Rukesa 30 – 30Badasa 20 – 20Kijiji 30 – 30
– 44 44Total 80 44 124
3.2. Data collection for economic parameters
The underlying data for the components utility (Ui) and costs (Ci)was gathered through the use of stated preference methods (SP): achoice experiment (CE) for the utility and contingent valuation (CV)for the costs. The source of the data is the most fundamentaldifference between SP and RP methods. SP methods directly measurerespondents' preferences for changes in public or environmentalgoods by asking respondents while for RPmethods, data is collected inmarkets from real market transactions. When deriving values/utilitiesof a breed through a RP approach, cultural and other non-marketvalues are often neglected, leading to underestimation and thereforesub-optimal conservation and use. SP techniques, in contrast, arecommonly applied for assessing the values of goods that are either nottraded in markets at all or whose market prices are largelyunderestimated because of their good public character. Non-marketvalues are part of the TEV of a breed, a broadly applied concept inenvironmental economics (for a detailed discussion on the generalconcept of TEV see, for example, Pearce and Moran (1994), and withparticular regard to the TEV of cattle see Zander and Holm-Müller(2007)).
Both methods estimate a welfare change for respondents as aresult of the provision of an environmental or public good. They elicitrespondents' preferences by identifying the amount they would bewilling to pay (WTP) for improvements in their quality and/or
quantity or the minimumwillingness to accept (WTA) compensationto bear a decrease in quality and/or quantity contingent upon thecreation of a market or other means of payment (Mitchell and Carson,1989). Respondents make statements about their preferences withoutactually initiating the proposed change.
A CE relies on carefully designed tasks or “experiments” to revealthe factors that influence choice (Hanley et al., 1998). The modelspecifics and the design of the CE whose results we use here arepresented in Zander and Drucker (2008). The aim of the CE was toreveal which attributes out of the ones used in the design (whichweretick tolerance, fertility, body size, horn condition, market price,watering frequency and traction suitability for bulls and milk yieldfor cows) are important when purchasing cows and bulls on localmarkets and how much money buyers are willing to pay for therelevant attributes. On the basis of these WTP estimates for singleattributes, and depending on which attributes certain Boranasubtypes and other breeds express, the WTP for whole animalscould be simulated. This WTP for a breed/subtype can be interpretedas the utility livestock-keepers gain from keeping it. This translationfrom WTP to utility is grounded on the underlying consumer's utilitymaximising and welfare theory (see e.g. Freeman, 2003).
The CV undertaken was designed to understand how muchcompensation respondents would require to change their herds toEB, i.e. instead of utility of animals per se (as measured by the CE),respondents only stated the differences in the utility of two animals(the approach and results are presented in Zander (2006)). Therequired compensation was measured by respondents' WTA com-pensation for keeping the EB. The reason we opted to use WTAestimates was motivated by the property rights structure of Boranacattle as private goods and by the fact that we assumed negativechanges in livestock-keepers' income when keeping EB instead ofother breeds such as improved crossbreeds. The compensation thatwould then be required to absorb these negative changes is measuredby respondents' statedWTA and constitutes the cost of conserving EB.
3.3. Sampling
Multistage stratified sampling was employed in the neighboringcountries of Kenya (124 livestock-keepers) and Ethiopia (246 live-stock-keepers). Country samples were further stratified into fourlocations in the Marsabit district of Kenya (Badasa, Burbisa, Kijiji,Rukesa) and peasant associations in the Ethiopian Borana zone (DidiHara, Finchawa, Wachile, Web) (see Table 2). The different villages(see Fig. 1) were selected based on socio-economic, environmentaland infrastructure conditions. Interviews were held between October2003 and January 2004. Every respondent was interviewed one by one
Table 3Survival probabilities of cattle in the research area.
Parameter EB KB OB SB Guji SEAZ
TR 0.1 0.0a 0.05 0.1 0.05 0.05DI 0.1 0.0 0.1 0.05 0.1 0.05DC 0.05 0.1 0.05 0.05 0.05 0.1DS 0.1 0.0 0.1 0.05 0.05 0.05OR 0.1 0.0 0.1 0.05 0.0 0.0CO 0.05 0.05 0.1 0.1 0.1 0.1MA 0.1 0.0 0.1 0.1 0.0 0.0AR 0.05 0.1 0.05 0.1 0.05 0.05∑ 0.65 0.25 0.65 0.60 0.40 0.40Z 0.75 0.35 0.75 0.70 0.50 0.50
a source: DAD-IS (FAO, 2008); all other values are based on lead author's findings.
Table 4Results of the Weitzman approach for the three major Borana subtypes.
Subtype Ui Ci Di ΔPi Ri
OB 204 22 0 0.25 7.0EB 249 22 0 0.25 8.5SB 248 22 0 0.30 7.9OBK 223 50 0 0.25 3.3EBK 281 50 0 0.25 4.2SBK 284 50 0 0.30 4.0OBE 190 7 0 0.25 20.4EBE 206 7 0 0.25 22.1SBE 202 7 0 0.30 20.2
The subscripts E and K refer to Ethiopia and Kenya, respectively.
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by trained interpreters in their local languages and presented with asemi-structured questionnaire to elicit household data plus a furtherseven choice experiment (CE) questions in order to quantify theutilities of different cattle breeds and Borana subtypes to locallivestock-keepers. A third component of the survey involved acontingent valuation (CV) survey. This provided proxy estimates forthe costs of the conservation of Borana subtypes.
4. Results
We first recommend subtype(s) that should board Noah's ark onthe basis of cost-effectiveness. Secondly we determine the minimumnumber of animals of this particular subtype that should be taken onboard.
4.1. The assessment of conservation priorities
4.1.1. The change in survival probability (ΔPi)Livestock-keepers were asked several questions on a Likert Scale
regarding their attitude towards keeping exotic breeds; crossbreedingof exotic with Borana breeds; crossbreeding of local cattle withBorana; awareness of a decrease in Borana cattle; and the degradationof land and good pastures.
In summary, the differences in perceptions of Kenyan andEthiopian livestock-keepers can be narrowed down to three keyfactors:
• the importance of crossbreeding with local breeds is higher inEthiopia than in Kenya
• the importance of crossbreeding with exotic breeds and keepingexotic breeds per se is higher in Kenya than in Ethiopia
• awareness of risk of local extinction is higher in Ethiopia than inKenya
For comparative purposesΔPiwas calculated for the Guji breed, themost common non-Borana in the Ethiopian research area, and for theSmall East African Zebu (SEAZ) that is the dominant local breed inKenya alongside the Borana. Table 3 shows all calculated extinctionprobabilities.
4.1.2. Economic assessment: utility (Ui) and costs (Ci)Utility values are provided for the pooled data set (two country
average) for each Borana type as well as for each country individually.Utilities are presented in the form of WTP estimates for differentBorana subtypes. They were found to be slightly higher than themarket prices, indicating that livestock-keepers indeed benefit fromadditional utility other than that reflected in market prices. Thesedifferences in market price and WTP responses can be attributed tothe Borana cattle's provision of non-market values such as: toleranceto water shortages; tick tolerance; distinctive horn size and shape (asa cultural indicator); and, in males, suitability as draft animals. The CEfurther showed that respondents in Kenya gain higher net utility from
Borana cattle in general than in Ethiopia. In Ethiopia the EB providesthe highest utility (€206, compared to €202 for the SB and €190 for theOB), while in Kenya it is the SB with the highest perceived utility(€284, compared to €281 for the EB and €223 for the OB) (see Table 4).
Cost estimates are provided only for the EB subtype, representativefor all Borana cattle that could be conserved. Costs were found to varywith the production system and country (Kenya or Ethiopia). Themean cost for the two countries was €22 per EB (€7 for Ethiopia and€50 for Kenya); 63% of respondents did not require any compensationpayments at all (80% in Ethiopia but only 30% in Kenya) (see alsoZander 2006).
Metrick and Weitzman (1998, p. 25) show that dividing the utilityby the costs allows for the calculation of the expected gains permonetary unit expended. The expected gain for each Euro spent is€11.3 for the EB (€29.4 in Ethiopia and €5.6 in Kenya), € 9.3 for the OB(€27.1 in Ethiopia and € 4.5 in Kenya) and € 11.3 for the SB (€ 28.9 inEthiopia and € 5.7 in Kenya). Despite their high net utilities, due to therelatively high costs of conservation, the expected gains for each Eurospent for the subtypes in Kenya becomes quite small.
4.1.3. The ranking priority (Ri)Speaking in Weitzman's language, Noah would be urged to board
the EB first (REB=8.5), then the SB (RSB=7.9) and, if he still had notrun out of space on the Ark, the OB (ROB=7.0) (see Table 4). Within acountry, given that the costs of conservation are equal for all threesubtypes, Ri is only a function of Ui multiplied by zi. Hence, the higherthe value of Ui and the higher that of zi, the higher is Ri. It isnoteworthy that the ranking order is different between the tworesearch countries. In Ethiopia the OB ranked second (20.4), after theEB (22.1) but before the SB (20.2). In Kenya, the EB is ranked first (4.2),SB second (4.0) and OB third (3.3). However, in both countries, thehighest ranking priority was calculated for the EB and the highestabsolute score was found to be for the EB in Ethiopia (22.1). Thissuggests that conserving the EB in Ethiopia is cost-efficient as itprovides the highest genetic and economic contribution for each Eurospent on conservation.
4.1.4. Number of animals to be conservedHaving defined which animals should be taken on board Noah's
Ark, the next step involves finding how much space is needed onboard, i.e. what capacity should Noah bear in mind when building theArk? Noah needs to know how many animals he needs to start asuccessful breeding programme from scratch, i.e. what safe minimumstandard (SMS) he needs to meet. The SMS is defined as the minimumnumber of animals of one Borana subtype that are needed for aconservation programme tomake it feasible to rebuild the stock in thefuture (see Ready and Bishop, 1991; Drucker, 2006).
According to the FAO (1998, pp. 32) classification, a breed of cattleis “not at risk” when the total number of breeding females and malesare estimated to be greater than 1000 and 20 respectively. This wouldimply that 1020 animals should board the ark, but there is also theissue of managing the animals in a sustainable way so that their
Table 5Costs of conservation programmes for different Borana subtypes (in € p.a.).
Costs Strategy I Strategy II Strategy III
Number of animals conserved 1100 3300 1100Number of households involved 100 300 100Costs per animal 7 7 22Costs per household 77 77 242Total costs 8,100 24,300 25,400
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genetic distinctness is secured as a future gene pool. The managementof the animals also secures the owners' livelihoods as they receivedirect and indirect benefits from their husbandry. Although thedistribution of these 1020 animals to a single household might beconsidered efficient from a control and transaction cost point of view,it is not in accordance with a fair and equal distribution amongparticipating households in a community. Furthermore, a household'scapacity to manage a given number of animals must be taken intoaccount. Respondents claimed to be capable of handling 10 to 12animals per herd. Usually most animals in a herd are cows with onlyone to three bulls (with only one used for breeding while the othersare often castrated and used for traction). For simplicity, we assumethat every household receives 11 animals of the subtype that shouldbe conserved and we suggest that 100 households should participatein a community-based conservation programme. This leads to a totalstock of 1100 animals, with a minimum of 1000 cows.
4.2. Discussion
The Weitzman ranking scores provide an initial idea of the degreeof conservation priority for each Borana subtype. The value of asubtype is defined by its expected economic gain (the net benefit) andthe change in survival probability which can be achieved whenmeeting the conservation costs. In determining how these rankingsshould be taken into account within a conservation programme, it isnecessary to consider the specific goals of the programme. Thesecould include:
1) maintaining the subtype that is most likely to become extinct, orfor which the survival probability can be increasedmost for a givencost (conservation genetics perspective);
2) maintaining the subtype that maximises the utility for those whokeep it in-situ (livelihoods perspective); and
3) maintaining the subtype for which the costs are minimised(efficiency perspective).
The fraction of (2) divided by (3) provides the expected gain foreach Euro spent. As already shown, this expected gain is highest forthe EB and SB alike (when considering the pooled data set). From astrictly economic perspective, one could therefore argue that bothsubtypes should be given priority for conservation. However, from theconservation genetics perspective (1), based on survival and extinc-tion probabilities, the survival rate of the EB can be increased the mostwithin a given time horizon and therefore greater effort should be putinto its maintenance (as also indicated by the final highest rankingpriority). The conservation implications of these different perspec-tives are discussed in more detail in the following sub-sections.
4.2.1. Setting 1: conserving EB in Ethiopian communitiesThe ranking value for the conservation of the EB in Ethiopia was
the highest at 22.1 (see Table 4). Given that the CV responses revealthat almost 80% of livestock-keepers in Ethiopia would be willing toconserve the large-framed EB without receiving any compensation,conservation costs would be limited to those required for the initialimplementation of the programme, monitoring and maintenance.Specific “no compensation” households could be identified through aform of stewardship auctions, with those livestock-keepers willing toexchange their current breeds for the EB (while being confident thatthey would not incur a decline in household welfare) being includedas participants. However, if households could not be targeted in thisway, and given that the average payment required by Ethiopianlivestock-keepers (theirWTA compensation) for maintaining the EB is€7 per animal (see Table 4), each participating households wouldneed to receive €77 per annum. Costs for conserving 1,100 EB animalsin Ethiopia would thus be €7700 p.a. plus a further 5% (followingDrucker, 2006) to cover administration and monitoring costs add,totalling approximately €8100 p.a. (see Table 5).
4.2.2. Setting 2: conserving all subtypes in Ethiopian communitiesThe advantage of conserving a single subtype like the EB is that it
has a defined set of characteristics and parameters and that itsappearance, production parameters, and its utility to local livestock-keepers are well known. Populations from such a subtype could bescreened for undocumented characteristics in the future and desirablegenes accessed through conventional breeding techniques or geneticengineering. The disadvantage of conserving this single subtype isthat the decision is being made on the basis of non-genetic factors.Ideally genetic analysis would be undertaken of all subtypes toidentify the most diverse founder stock within the Borana for an in-situ conservation programme but this was beyond the scope of thisstudy.
Hence, even though the ranking scores prioritise the EB forconservation investment, it might be reasonable to conserve morethan one subtype. We argue that targeting all three subtypes with thegoal of conserving as many genes as possible is the best insurancestrategy. There are two ways of conserving more than one subtype,either by conserving them separately or by combining them into asingle gene pool.
Given that most people within Ethiopian communities did notrequire compensation we suggest that a gene pool will be conservedmost effectively by keeping 1100 animals of each of the EB, the SB andthe OB in Ethiopia. All three subtypes in the order EB, SB and OB havehigher ranks in Ethiopia than in Kenya (see Table 4). The total costswould rise to €24,300 p.a. (3⁎€7700 plus 5% transaction andmonitoring costs) as 300 households would be targeted (Table 5).
4.2.3. Setting 3: conserving EB in Ethiopian and Kenyan communitiesA decision to conserve a subtype in both countriesmay be taken for
reasons of equity and to spread risk from disease, drought or socialdisruption. The EB subtype has the highest ranking in both Kenya andin Ethiopia (Kenya: 4.2; Ethiopia: 22.1). Given that only 30% oflivestock-keepers in Kenya stated that they do not need anycompensation, livestock-keepers who want to participate in con-servation are likely to need payments if they are to substitute theirbreeds with the EB. Splitting the herd equally between Kenya andEthiopia would cost about €25,400 p.a. (Table 5). Alternatively, a safeminimum population of 1100 could be maintained in each country, inwhich case the costs would double to €50,800 p.a., and involve 200households in total.
The main disadvantage of subsidizing the conservation of only onesubtype like the EB is that the population sizes of other subtypes andeven other local breeds might decrease and become threatened. Thishas to be monitored at the local level and one way to alleviate thisthreat is to geographically limit the conservation of the EB to its placesof origin (and to the Borana people).
5. Conclusions
Despite critical assessments of the Weitzman approach, weconsider that it is well suited to facilitating decision-making onconservation strategies for the Borana breed. The chosen approachallows Borana subtypes to be ranked based on a combination ofeconomic factors and changes in survival rates when included in aconservation programme. The findings of this study could usefully be
2057K.K. Zander et al. / Ecological Economics 68 (2009) 2051–2057
incorporated into livestock management programmes and breedingsoftware used for optimising breeding programmes. This study is oneof the first to focus on the two components of utility and cost whenapplying the Weitzman approach. Furthermore stated preferencemethodologies would appear to be a suitable tool for incorporatingeconomic values into Weitzman's cost-effectiveness framework.
Beyond the specific application described here, we show thatWeitzman's cost-effectiveness approach can be the basis for decision-making under incomplete information, as is usually the case withlivestock conservation. In the study of Borana, we had detailedeconomic information and indicators of the risk status but have had todo this in the absence of genetic information. In other cases, geneticinformation may be at hand, while economic information may not beavailable. Taking this framework as a guideline, and using adequateproxies for the missing quantities, structured decision-making is stillpossible and will lead, we believe, to more rational and justifiableconservation decisions than the usual single-parameter-based ad hoccriteria.
We only investigated three subtypes of a breed but the underlyingapproach can be extended to different breeds as well. In that case thesame CE (with the same criteria in terms of attributes to be evaluated)must be undertaken for different breeds. Regarding the costcomponent of the Weitzman theorem, the CV constitutes a suitableapproach, but where market data exists, the replacement costapproach might also be a promising tool.
Acknowledgments
This study was financially supported by the Robert BoschFoundation. We thank Stefanie Engel and Stephen Garnett forproviding valuable comments and advice on previous drafts. Wefurther appreciate collaboration with the International LivestockResearch Institute (ILRI) in Addis Ababa (Ethiopia), the GTZ in Negelle(Ethiopia), SORDU in Yabello (Ethiopia), KARI in Marsabit (Kenya) aswell as with the Center for Development Research (ZEF) in Bonn.
References
Coppock, D.L., 1994. The Borana Plateau of Southern Ethiopia: Synthesis of PastoralResearch, Development and Change, 1980–91. International Livestock Center forAfrica, Addis Ababa.
Dolan, R.B., 1997. The Orma Boran – ATrypanotolerant East African Breed.World AnimalReview, vol. 89. 2 pp.
Drucker, A.G., 2006. An application of the use of safe minimum standards in theconservation of livestock biodiversity. Environment and Development Economics.Issue 01, 77–94.
Food and Agriculture Organisation (FAO), 1998. Primary Guidelines for Development ofNational Farm Animal Genetic Resources Management Plans, Rome, Italy.
FAO, 2000. World Watch List of Domestic Animal Diversity, 3rd ed. FAO, Rome, Italy.FAO, 2007. In: Rischkowsky, Barbara, Pilling, Dafydd (Eds.), The State of the World's
Animal Genetic Resources for Food and Agriculture. Rome, Italy.FAO, 2008.DomesticatedAnimalDiversity InformationSystem(DAD-IS). http://dad.fao.org.Freeman III, A.M., 2003. The Measurement of Environmental and Resource Values:
Theory and Methods 2nd Edition. Resources for the Future, Washington, D.C.Gandini, G.C., Villa, E., 2003. Analysis of the cultural value of local livestock breeds: a
methodology. Journal of Animal Breeding and Genetics 120 (1), 1–11.
Haile Mariam, M., Mamfors, B., Philipsson, J., 1998. Boran-Indigenous African cattle withPotential. Current No. 17/18.
Hanley, N., Wright, R.E., Adam owicz, V., 1998. Using choice experiments to value theenvironmental. Environmental and Resource Economics 11 (3–4), 413–428.
Hogg, R., 1997. Pastoralists. Ethnicity and the State in Ethiopia. HAAN Publishing,London, UK.
Homann, S., 2004. Indigenous Knowledge of Borana Pastoralists in Natural ResourceManagement: A Case Study from Southern Ethiopia. Cuvillier Verlag, Goettingen,Germany. 234 pp.
International Livestock Research Institute (ILRI), 2006. Domestic Animal GeneticResources Information System (DAGRIS). In: Rege, J.E.O., Ayalew, W., Getahun, E.(Eds.), ILRI, Addis Ababa. Ethiopia, http://dagris.ilri.cgiar.org.
Köhler-Rollefson, I., 2000. Management of Animal Genetic Diversity at CommunityLevel – Managing Agrobiodiversity in Rural Areas, GTZ, Eschborn, Germany.
Metrick, A., Weitzman, M.L., 1998. Conflicts and choices in biodiversity preservation.Journal of Economic Perspectives 12, 21–34.
Mitchell, R.C., Carson, R.T., 1989. Using surveys to value public goods: the contingentvaluation method. Resource for the Future, Washington, DC.
Ostermann, O.P., 1998. The need for management of nature conservation sitesdesignated under Natura 2000. Journal of Applied Ecology 35, 968–973.
Payne, W.J.A., Hodges, J., 1997. Tropical Cattle – Origins, Breeds and Breeding Policies.Blackwell Science, UK.
Pearce, D., Moran, D., 1994. The economic valuation of biodiversity. The WorldConservation Union (IUCN). Earthcan Publications Ltd, London, UK.
Ready, R., Bishop, R., 1991. Endangered species and the safe minimum standard.American Journal of Agricultural Economics 73, 309–312.
Rege, J.E.O., 1999. The state of African cattle genetic resources. I. Classificationframework and identification of threatened and extinct breeds. FAO/UNEP AnimalGenetic Resources Information Bulletin, pp. 1–25.
Rege, J.E.O., Gibson, J.P., 2003. Animal genetic resources and economic development:issues in relation to economic valuation. Ecological Economics 45, 319–330.
Rege, J.E.O, Kahi, A., Okomo-AdhiamboM., Mwacharo J., Hanotte, O., 2001. Zebu cattle ofKenya: Uses, performance, farmer preferences, measures of genetic diversity andoptions for improved use. Animal Genetic Resources Research 1. ILRI (InternationalLivestock Research Institute), Nairobi, Kenya.
Reist-Marti, S., Simianer, H., Gibson, J., Hanotte, O., Rege, J.E.O., 2003. Weitzman'sapproach and conservation of breed diversity: an application to African cattlebreeds. Conservation Biology 17, 1299–1311.
Simianer, H., 2002. Noah's dilemma: which breeds to take aboard the ark? Proc. 7thWorld Congress on Genetics Applied to Livestock Production, CD-Rom Commu-nication No. 26-02.
Simianer, H., Marti, S.B., Gibson, J., Hanotte, O., Rege, J.E.O., 2003. An approach to theoptimal allocation of conservation funds to minimise loss of genetic diversitybetween livestock breeds. Ecological Economics 45, 377–392.
Simianer, H., 2005. Decision making in livestock conservation. Ecological Economics 53,559–572.
van der Heide, M., van den Bergh, C.J.M., van Ierland, E.C., 2005. Extending Weitzman'seconomic ranking of biodiversity protection: combining ecological and geneticconsiderations. Ecological Economics 55, 218–223.
Weitzman, M.L., 1992. On diversity. Quarterly Journal of Economics CVII, 363–405.Weitzman, M., 1993. What to preserve? An application of diversity theory to crane
conservation. Quarterly Journal of Economics 108, 157–183.Weitzman, M.L., 1998. The Noah's Ark problem. Econometrica 66, 1279–1298.Zander, K., 2006. Modelling the value of farm animal genetic resources – facilitating
priority setting for the conservation of cattle in East Africa. Dissertation, Universityof Bonn. http://hss.ulb.uni-bonn.de/diss_online/landw_fak/2006/zander_kerstin.
Zander, K., Holm-Müller, K., 2007. Valuing farm animal genetic resources by using achoice ranking method. In: Meyerhoff, J., Lienhoop, N., Elsasser, P. (Eds.), StatedPreference Methods for Environmental Valuation: Applications from Austria andGermany. Metropolis, Marburg, Germany.
Zander, K.K., Drucker, A.G., 2008. Conserving what's important: using choice modelscenarios to value local cattle breeds in East Africa. Ecological Economics 68, 34–45.doi:10.1016/j.ecolecon.2008.01.023.
Zavaleta, E.S., Hulvey, K.B., 2004. Realistic species losses disproportionately reducegrassland resistance to biological invaders. Science 306, 1175–1177.
