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Prithiviraj Fernando - One of the best experts on this subject based on the ideXlab platform.
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first country wide survey of the endangered Asian Elephant towards better conservation and management in sri lanka
Oryx, 2021Co-Authors: Prithiviraj Fernando, M Channa K R De Silva, L K A Jayasinghe, H K Janaka, Jennifer PastoriniAbstract:The Endangered Asian Elephant Elephas maximus comes into widespread conflict with agrarian communities, necessitating active management. The species’ distribution is of primary importance for management planning. However, data-based countrywide distribution maps have not been available for any of the 13 Asian Elephant range states. We conducted a 5 × 5 km grid-based questionnaire survey in Sri Lanka to produce an island-wide Elephant distribution map. Elephants occur over 59.9% of Sri Lanka and people are resident in 69.4% of Elephant range, indicating the challenge of separating people and Elephants at a landscape scale. Elephants in Sri Lanka have lost 16.1% of their range since 1960 but their current distribution remains largely contiguous. We found the range of adult males was 15.1% greater, and less seasonal, than that of herds, possibly because males have a higher tolerance for conflict with people. The distribution of conflict coincided with the co-occurrence of humans and Elephants. We conclude that a human–Elephant coexistence model is the only viable option for effectively mitigating human–Elephant conflict and conserving Elephants in Sri Lanka. The findings are currently being used to effect a paradigm change in Elephant conservation and management in the country.
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population differentiation within and among Asian Elephant elephas maximus populations in southern india
Heredity, 2005Co-Authors: T N C Vidya, Prithiviraj Fernando, Don J Melnick, Raman SukumarAbstract:Southern India, one of the last strongholds of the endangered Asian Elephant (Elephas maximus), harbours about one-fifth of the global population. We present here the first population genetic study of free-ranging Asian Elephants, examining within- and among-population differentiation by analysing mitochondrial DNA (mtDNA) and nuclear microsatellite DNA differentiation across the Nilgiris-Eastern Ghats, Anamalai, and Periyar Elephant reserves of southern India. Low mtDNA diversity and 'normal' microsatellite diversity were observed. Surprisingly, the Nilgiri population, which is the world's single largest Asian Elephant population, had only one mtDNA haplotype and lower microsatellite diversity than the two other smaller populations examined. There was almost no mtDNA or microsatellite differentiation among localities within the Nilgiris, an area of about $15,000 km^2$. This suggests extensive gene flow in the past, which is compatible with the home ranges of several hundred square kilometres of Elephants in southern India. Conversely, the Nilgiri population is genetically distinct at both mitochondrial and microsatellite markers from the two more southerly populations, Anamalai and Periyar, which in turn are not genetically differentiated from each other. The more southerly populations are separated from the Nilgiris by only a 40-km-wide stretch across a gap in the Western Ghats mountain range. These results variably indicate the importance of population bottlenecks, social organization, and biogeographic barriers in shaping the distribution of genetic variation among Asian Elephant populations in southern India.
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Isolation and characterization of tri‐ and tetranucleotide microsatellite loci in the Asian Elephant, Elephas maximus
Molecular Ecology Notes, 2001Co-Authors: Prithiviraj Fernando, T N C Vidya, Don J MelnickAbstract:Asian Elephants (Elephas maximus) are an endangered species. Their future survival depends on intensive conservation and management, based on in-depth knowledge of particular populations. Molecular genetic methods, especially microsatellite analysis through noninvasive sampling, provides an effective means of obtaining such information. The use of tri- and tetranucleotide microsatellite markers is advantageous in noninvasive sampling through dung analysis. Here we describe the isolation and characterization of five tri- and tetranucleotide markers in the Asian Elephant. All five loci were found to be polymorphic in a sample of 20 Asian Elephants from Sri Lanka.
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molecular genetic and behavioral analysis of social organization in the Asian Elephant elephas maximus
Behavioral Ecology and Sociobiology, 2000Co-Authors: Prithiviraj Fernando, Russell LandeAbstract:We report on the genetic evaluation and behav- ioral study of social organization in the Asian Elephant (Elephas maximus). Although Asian Elephants and Afri- can Elephants (Loxodonta africana) were previously thought to have similar social organizations, our results demonstrate a substantial difference in the complexity and structure of Asian Elephant social groupings from that described for African savanna Elephants. Photo- graphic cataloging of individuals, radio telemetry, and be- havioral observations in Ruhuna National Park, Sri Lan- ka, enabled us to assign associated females and young to four groups with overlapping ranges. Genetic sampling of individuals from the four groups in Ruhuna National Park and three other groups in surrounding areas, conducted through PCR amplification and sequencing of mitochon- drial DNA from dung, supported the matriarchal nature of female groups and the lack of inter-group transfer of females. Behaviorally and genetically, the identified so- cial groups were best described as "family groups". We did not find any evidence for the existence of social groups of higher complexity than family groups.
Raman Sukumar - One of the best experts on this subject based on the ideXlab platform.
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Comparative sequence analyses of genome and transcriptome reveal novel transcripts and variants in the Asian Elephant Elephas maximus
Journal of Biosciences, 2015Co-Authors: Puli Chandramouli Reddy, Raman Sukumar, Ishani Sinha, Ashwin Kelkar, Farhat Habib, Saurabh J. Pradhan, Sanjeev GalandeAbstract:The Asian Elephant Elephas maximus and the African Elephant Loxodonta africana that diverged 5–7 million years ago exhibit differences in their physiology, behaviour and morphology. A comparative genomics approach would be useful and necessary for evolutionary and functional genetic studies of Elephants. We performed sequencing of E. maximus and map to L. africana at ~15X coverage. Through comparative sequence analyses, we have identified Asian Elephant specific homozygous, non-synonymous single nucleotide variants (SNVs) that map to 1514 protein coding genes, many of which are involved in olfaction. We also present the first report of a high-coverage transcriptome sequence in E. maximus from peripheral blood lymphocytes. We have identified 103 novel protein coding transcripts and 66-long non-coding (lnc)RNAs. We also report the presence of 181 protein domains unique to Elephants when compared to other Afrotheria species. Each of these findings can be further investigated to gain a better understanding of functional differences unique to Elephant species, as well as those unique to Elephantids in comparison with other mammals. This work therefore provides a valuable resource to explore the immense research potential of comparative analyses of transcriptome and genome sequences in the Asian Elephant.
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social organization of the Asian Elephant elephas maximus in southern india inferred from microsatellite dna
Journal of Ethology, 2005Co-Authors: T N C Vidya, Raman SukumarAbstract:Social organization of the Asian Elephant (Elephas maximus) is not well understood in the absence of long-term studies of identified individuals. Adult Asian Elephant females and their young offspring of both sexes form matriarchal groups, with pubertal males dispersing from natal groups, but whether these social groups represent families and whether males show locational or social dispersal were unknown. Using nuclear microsatellite loci amplified from dung-extracted DNA of free-ranging Elephants in a large southern Indian population, we demonstrate that female-led herds comprise closely related individuals that are indeed families, and that males exhibit non-random locational dispersal.
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population differentiation within and among Asian Elephant elephas maximus populations in southern india
Heredity, 2005Co-Authors: T N C Vidya, Prithiviraj Fernando, Don J Melnick, Raman SukumarAbstract:Southern India, one of the last strongholds of the endangered Asian Elephant (Elephas maximus), harbours about one-fifth of the global population. We present here the first population genetic study of free-ranging Asian Elephants, examining within- and among-population differentiation by analysing mitochondrial DNA (mtDNA) and nuclear microsatellite DNA differentiation across the Nilgiris-Eastern Ghats, Anamalai, and Periyar Elephant reserves of southern India. Low mtDNA diversity and 'normal' microsatellite diversity were observed. Surprisingly, the Nilgiri population, which is the world's single largest Asian Elephant population, had only one mtDNA haplotype and lower microsatellite diversity than the two other smaller populations examined. There was almost no mtDNA or microsatellite differentiation among localities within the Nilgiris, an area of about $15,000 km^2$. This suggests extensive gene flow in the past, which is compatible with the home ranges of several hundred square kilometres of Elephants in southern India. Conversely, the Nilgiri population is genetically distinct at both mitochondrial and microsatellite markers from the two more southerly populations, Anamalai and Periyar, which in turn are not genetically differentiated from each other. The more southerly populations are separated from the Nilgiris by only a 40-km-wide stretch across a gap in the Western Ghats mountain range. These results variably indicate the importance of population bottlenecks, social organization, and biogeographic barriers in shaping the distribution of genetic variation among Asian Elephant populations in southern India.
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conservation of a flagship species prioritizing Asian Elephant elephas maximus conservation units in southern india
Current Science, 2002Co-Authors: Arun B Venkataraman, Venkatesa N Kumar, Surendra Varma, Raman SukumarAbstract:The Asian Elephant (Elephas maximus) is believed to number about 45,000 in the wild and is distributed across several populations over South and Southeast Asia. It is an important flagship species for the conservation of biodiversity as well as being a cultural symbol of the people of this region. We analyse a Geographical Information System database of administrative forest divisions constituting four Project Elephant Reserves designated for southern India, in an attempt to prioritize them for specific conservation action and funding allocation. We compute a conservation value for each of these divisions by using five variables characterizing habitat, population and biodiversity attributes. We also compute threat values for each, using two variables which represent the most significant threats. Based on a cluster analysis we demonstrate that divisions with high conservation values have large Elephant distribution areas, preferred habitat areas and Elephant
Nikorn Thongtip - One of the best experts on this subject based on the ideXlab platform.
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effect of pre freeze semen quality extender and cryoprotectant on the post thaw quality of Asian Elephant elephas maximus indicus semen
Cryobiology, 2013Co-Authors: Podjana Imrat, Nikorn Thongtip, Sittidet Mahasawangkul, S Jansittiwate, Piyawan Suthanmapinanth, Kulnasan Saikhun, Edita Sostaric, Pettisak Sombutputorn, Anuchai Pinyopummin, B ColenbranderAbstract:Semen cryopreservation and artificial insemination (AI) are potentially valuable methods for supporting the breeding management of endangered species like the Asian Elephant. Cryopreservation of Asian Elephant semen has however proven problematic with respect to maintenance of both adequate semen quality and fertility post-thaw. In this study, nine ejaculates from three adult bulls were used to compare the influence of extender (TEST versus INRA96®) and penetrating cryoprotectants (3% glycerol, 5% glycerol and 4% methylformamide) on post-thaw semen quality. We demonstrate that not only the freezing process, but also the quality of the semen before freezing, significantly influences the freezability of Asian Elephant semen. Pre-freeze motility, viability, semen volume, semen pH, sperm concentration and the incidence of sperm mid-piece and tail abnormalities all significantly (p<0.05) affected post-thaw semen quality. While extender and cryoprotectant did not significantly affect any of the above semen quality parameters post-thaw, the skim-milk based extender (INRA96®) preserved DNA integrity better (p<0.05) than the egg yolk extender (TEST). Considerable between-ejaculate variation in all post-thaw semen quality parameters was also noted. It is concluded that strict criteria for semen quality is essential for the selection of Asian Elephant bull ejaculates suitable for cryopreservation; stricter initial selection should improve the mean post-thaw quality.
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Surgical Removal of Urethral and Bladder Stones in Female Asian Elephant (Elephas maximus) by Episiotomy and Urethrotomy
Thai Journal of Veterinary Medicine, 2013Co-Authors: Nikorn Thongtip, Benjapol Lorsanyaluck, Manakorn Sukmak, Sirinart Chaichanathong, Naris Thengchaisri, Pornchai Sunyathitiseree, Worawidh WajjwalkuAbstract:A 45-year-old female Asian Elephant (Elephas maximus) was presented with urinary incontinence and solid masses at the perineal area. Vaginoscopy revealed stricture of the vaginal vestibule. Trans skin and rectal ultrasonography demonstrated presence of hyperechogenic uroliths. Episiotomy and urethrotomy were performed after standing sedation with xylazine and perineal infiltration with lidocaine. Total of 8 kg urethral calculi were retrieved manually. Calcium carbonate was identified as the main component of the stones. Due to acute urinary obstruction after the operation, an episiotomy was left open allowing urine to pass through the incision. Following urine scalding, necrotic tissues were detected along the tracts below the incision wound through umbilicus. Daily wound cleaning and antibiotics treatment for one month were performed. The episiotomy wound was left to heal by secondary intention and led to a 2 cm stricture. The healing process completed in 5 months post-operatively. The Elephant can urinate via normal tract in 8 months after surgery.
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the dynamics of sperm dna stability in Asian Elephant elephas maximus spermatozoa before and after cryopreservation
Theriogenology, 2012Co-Authors: Podjana Imrat, Nikorn Thongtip, Sittidet Mahasawangkul, M Hernandez, S Rittem, J Gosalvez, William V HoltAbstract:The purpose of this study was to investigate the occurrence of sperm DNA fragmentation in Asian Elephant (Elephas maximus) spermatozoa at various processing stages before and after cryopreservation. Five semen samples from four Elephants were assessed at four different stages during processing; after (1) collection and reextension in TEST-egg yolk; (2) cooling to 5 °C; (3) equilibration for 1 h with glycerol; (4) thawing. An experimental approach was adopted that allowed comparisons of DNA fragmentation rates developed after the various processing stages. For this, spermatozoa were incubated in TEST-yolk media at 37 °C for 0, 4, 8, 24 and 48 h, and sperm DNA fragmentation rates were estimated using an Elephant-specific Halosperm procedure. Incubation at 37 °C induced a rapid increase in DNA fragmentation, and significant differences between males were observed. The overall rate of increase over 4 h was estimated at about 5% per hour, and no significant changes to this rate were observed at the different processing stages, even, including the post-thaw samples. As semen quality of the five ejaculates was relatively poor, the basic semen parameter data were compared with nine different samples collected 11 mo earlier to see whether the tested samples were atypical or representative of the population, As there was no significant difference between the two sets of samples, it is believed that the samples tested for DNA stability were not unusually sensitive. These results suggest that Asian Elephant spermatozoa are more susceptible to DNA fragmentation than spermatozoa of other mammals.
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assessment of viability and acrosomal status of Asian Elephant elephas maximus sperm after treatment with calcium ionophore and heparin
Journal of The South African Veterinary Association-tydskrif Van Die Suid-afrikaanse Veterinere Vereniging, 2009Co-Authors: Nikorn Thongtip, Sittidet Mahasawangkul, Anuchai Pinyopummin, Kornchai Kornkaewrat, Mayurachat Saardrit, Tassanee Faisaikarm, Yindee Kitiyanant, Kulnasan SaikhunAbstract:Knowledge about the acrosomal status of Asian Elephant (Elephas maximus) sperm is extremely limited. The objective of this study was to evaluate the viability and acrosomal status of Asian Elephant sperm following induction by calcium ionophore and heparin using propidium iodide (PI) and fluorescein isothiocyanate conjugated peanut agglutinin (FITC-PNA). Semen samples were collected from Elephant bulls by manual stimulation. Semen was diluted with extender, cooled to 4°C and transported to a laboratory for the experiment. Sperm cells were incubated in modified Tyrode's medium containing either 1mM calcium ionophore or 10 mg/ml heparin for 5 h at 39°C. Sperm recovered at the onset (0 h), 1, 2, 3, 4 and 5 h of incubation were simultaneously assessed for the viability and acrosomal status using dual staining of FITC-PNA and PI. Results were confirmed by transmission electron microscopy. A progressive increase in the proportion of live-acrosome reacted sperm was observed within 3 h of incubation in both treatment groups which slightly decreased at 4 to5 h of incubation. At 1 to 3 h of incubation, the percentage of live-acrosome reacted sperm induced by calcium ionophore was higher (P < 0.05) than those induced by heparin and the control. However, there were no statistical differences at 4 to 5 h of incubation. A progressive reduction of the percentage of motile sperm was observed in the control as well as both treatment groups. Sperm motility decreased sharply when they were incubated in calcium ionophore compared with incubation in heparin and control groups. These results indicate that the occurrence of live-acrosome reacted sperm in the Asian Elephant was induced by calcium ionophore at a rate higher than that induced by heparin.
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potential factors affecting semen quality in the Asian Elephant elephas maximus
Reproductive Biology and Endocrinology, 2008Co-Authors: Nikorn Thongtip, J Saikhun, Sittidet Mahasawangkul, Kornchai Kornkaewrat, Pornsawan Pongsopavijitr, Nucharin Songsasen, Anuchai PinyopumminAbstract:Background One of the major obstacles in using artificial insemination to manage genetics of Elephant population in captivity is the large variations in semen quality among ejaculates within the same and among individuals. The objectives of this study were to determine the influences of (1) age (2) seasonality (3) and circulating testosterone (SrTest), triiodothyronine (SrT3) and tetraiodothyronine (SrT4), as well as seminal (4) testosterone (SpTest), zinc (SpZn) and protein (SpTP) on semen quality in the Asian Elephant
Sittidet Mahasawangkul - One of the best experts on this subject based on the ideXlab platform.
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effect of pre freeze semen quality extender and cryoprotectant on the post thaw quality of Asian Elephant elephas maximus indicus semen
Cryobiology, 2013Co-Authors: Podjana Imrat, Nikorn Thongtip, Sittidet Mahasawangkul, S Jansittiwate, Piyawan Suthanmapinanth, Kulnasan Saikhun, Edita Sostaric, Pettisak Sombutputorn, Anuchai Pinyopummin, B ColenbranderAbstract:Semen cryopreservation and artificial insemination (AI) are potentially valuable methods for supporting the breeding management of endangered species like the Asian Elephant. Cryopreservation of Asian Elephant semen has however proven problematic with respect to maintenance of both adequate semen quality and fertility post-thaw. In this study, nine ejaculates from three adult bulls were used to compare the influence of extender (TEST versus INRA96®) and penetrating cryoprotectants (3% glycerol, 5% glycerol and 4% methylformamide) on post-thaw semen quality. We demonstrate that not only the freezing process, but also the quality of the semen before freezing, significantly influences the freezability of Asian Elephant semen. Pre-freeze motility, viability, semen volume, semen pH, sperm concentration and the incidence of sperm mid-piece and tail abnormalities all significantly (p<0.05) affected post-thaw semen quality. While extender and cryoprotectant did not significantly affect any of the above semen quality parameters post-thaw, the skim-milk based extender (INRA96®) preserved DNA integrity better (p<0.05) than the egg yolk extender (TEST). Considerable between-ejaculate variation in all post-thaw semen quality parameters was also noted. It is concluded that strict criteria for semen quality is essential for the selection of Asian Elephant bull ejaculates suitable for cryopreservation; stricter initial selection should improve the mean post-thaw quality.
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the dynamics of sperm dna stability in Asian Elephant elephas maximus spermatozoa before and after cryopreservation
Theriogenology, 2012Co-Authors: Podjana Imrat, Nikorn Thongtip, Sittidet Mahasawangkul, M Hernandez, S Rittem, J Gosalvez, William V HoltAbstract:The purpose of this study was to investigate the occurrence of sperm DNA fragmentation in Asian Elephant (Elephas maximus) spermatozoa at various processing stages before and after cryopreservation. Five semen samples from four Elephants were assessed at four different stages during processing; after (1) collection and reextension in TEST-egg yolk; (2) cooling to 5 °C; (3) equilibration for 1 h with glycerol; (4) thawing. An experimental approach was adopted that allowed comparisons of DNA fragmentation rates developed after the various processing stages. For this, spermatozoa were incubated in TEST-yolk media at 37 °C for 0, 4, 8, 24 and 48 h, and sperm DNA fragmentation rates were estimated using an Elephant-specific Halosperm procedure. Incubation at 37 °C induced a rapid increase in DNA fragmentation, and significant differences between males were observed. The overall rate of increase over 4 h was estimated at about 5% per hour, and no significant changes to this rate were observed at the different processing stages, even, including the post-thaw samples. As semen quality of the five ejaculates was relatively poor, the basic semen parameter data were compared with nine different samples collected 11 mo earlier to see whether the tested samples were atypical or representative of the population, As there was no significant difference between the two sets of samples, it is believed that the samples tested for DNA stability were not unusually sensitive. These results suggest that Asian Elephant spermatozoa are more susceptible to DNA fragmentation than spermatozoa of other mammals.
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assessment of viability and acrosomal status of Asian Elephant elephas maximus sperm after treatment with calcium ionophore and heparin
Journal of The South African Veterinary Association-tydskrif Van Die Suid-afrikaanse Veterinere Vereniging, 2009Co-Authors: Nikorn Thongtip, Sittidet Mahasawangkul, Anuchai Pinyopummin, Kornchai Kornkaewrat, Mayurachat Saardrit, Tassanee Faisaikarm, Yindee Kitiyanant, Kulnasan SaikhunAbstract:Knowledge about the acrosomal status of Asian Elephant (Elephas maximus) sperm is extremely limited. The objective of this study was to evaluate the viability and acrosomal status of Asian Elephant sperm following induction by calcium ionophore and heparin using propidium iodide (PI) and fluorescein isothiocyanate conjugated peanut agglutinin (FITC-PNA). Semen samples were collected from Elephant bulls by manual stimulation. Semen was diluted with extender, cooled to 4°C and transported to a laboratory for the experiment. Sperm cells were incubated in modified Tyrode's medium containing either 1mM calcium ionophore or 10 mg/ml heparin for 5 h at 39°C. Sperm recovered at the onset (0 h), 1, 2, 3, 4 and 5 h of incubation were simultaneously assessed for the viability and acrosomal status using dual staining of FITC-PNA and PI. Results were confirmed by transmission electron microscopy. A progressive increase in the proportion of live-acrosome reacted sperm was observed within 3 h of incubation in both treatment groups which slightly decreased at 4 to5 h of incubation. At 1 to 3 h of incubation, the percentage of live-acrosome reacted sperm induced by calcium ionophore was higher (P < 0.05) than those induced by heparin and the control. However, there were no statistical differences at 4 to 5 h of incubation. A progressive reduction of the percentage of motile sperm was observed in the control as well as both treatment groups. Sperm motility decreased sharply when they were incubated in calcium ionophore compared with incubation in heparin and control groups. These results indicate that the occurrence of live-acrosome reacted sperm in the Asian Elephant was induced by calcium ionophore at a rate higher than that induced by heparin.
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potential factors affecting semen quality in the Asian Elephant elephas maximus
Reproductive Biology and Endocrinology, 2008Co-Authors: Nikorn Thongtip, J Saikhun, Sittidet Mahasawangkul, Kornchai Kornkaewrat, Pornsawan Pongsopavijitr, Nucharin Songsasen, Anuchai PinyopumminAbstract:Background One of the major obstacles in using artificial insemination to manage genetics of Elephant population in captivity is the large variations in semen quality among ejaculates within the same and among individuals. The objectives of this study were to determine the influences of (1) age (2) seasonality (3) and circulating testosterone (SrTest), triiodothyronine (SrT3) and tetraiodothyronine (SrT4), as well as seminal (4) testosterone (SpTest), zinc (SpZn) and protein (SpTP) on semen quality in the Asian Elephant
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ultrastructural alterations of frozen thawed Asian Elephant elephas maximus spermatozoa
International Journal of Andrology, 2006Co-Authors: M Saardrit, Taweepoke Angkawanish, Nikorn Thongtip, J Saikhun, Mangkorn Damyang, Sittidet Mahasawangkul, S Jansittiwate, Tassanee Faisaikarm, Yindee Kitiyanant, K PavasuthipaisitAbstract:Intact plasma and acrosome membranes and functional mitochondria following cryopreservation are important attributes for the fertilizing ability of spermatozoa. In the present study, functional and ultrastructural changes of Asian Elephant spermatozoa after cryopreservation either in TEST + glycerol or HEPT + dimethyl sulphoxide (DMSO) were evaluated by fluorescent techniques and electron microscopy. Sperm frozen in TEST + glycerol had higher proportion of sperm with intact plasma (49.1 +/- 9.2% vs. 30.9 +/- 3.9%) and acrosomal (53.7 +/- 4.9% vs. 35.8 +/- 6.1%) membranes, as well as active mitochondria (57.0 +/- 7.2% vs. 42.0 +/- 5.0%) than those cryopreserved in HEPT + DMSO. The results obtained from electron microscopy were similar to those obtained by fluorescence microscopy. The percentage of normal spermatozoa was higher when spermatozoa were frozen in TEST + glycerol than those frozen in HEPT + DMSO (31.8 +/- 5.6 vs. 28.5 +/- 6.4). The ultrastructural alterations revealed by transmission electron microscopy could be classified as (i) distension of plasma membrane, while the acrosome was swollen; (ii) disruption or loss of plasma membrane, while acrosome was swollen with distended outer acrosomal membrane; (iii) disruption or loss of plasma and outer acrosomal membrane with leakage of acrosome content; (iv) extensive vesiculation of plasma and outer acrosomal membrane and leakage of acrosome content; (v) a complete loss of both plasma membrane and outer acrosomal membrane; and (vi) swelling of mitochondria. These findings suggest that the freezing and thawing procedure caused structural damage to Elephant spermatozoa, especially in the plasma membrane, acrosome and mitochondria. Fluorescence and electron microscopic evaluations are potentially a powerful tool in the analysis of Elephant spermatozoa after freezing and thawing.
Clement A Tisdell - One of the best experts on this subject based on the ideXlab platform.
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the net benefit of saving the Asian Elephant a policy and contingent valuation study
Ecological Economics, 2004Co-Authors: Ranjith Bandara, Clement A TisdellAbstract:Reports results from a contingent valuation (CV) survey of willingness to pay (WTP) for the conservation of the Asian Elephant of a sample of urban residents living in three selected housing schemes in Colombo, the capital of Sri Lanka. Face-to-face surveys were conducted using an interview schedule (IS). A non-linear logit regression model is used to analyse the respondents' responses for the payment principle questions and to identify the factors that influence their responses. We investigate whether urban residents' WTP for the conservation of Elephants is sufficient to compensate farmers for the damage caused by Elephants. We find that the beneficiaries (the urban residents) could compensate losers (the fanners in the areas affected by human-Elephant conflict, HEC) and be better off than in the absence of Elephants in Sri Lanka. Therefore, there is a strong economic case for the conservation of the wild Elephant population in Sri Lanka. However, we have insufficient data to determine the optimal level of this Elephant population in the Kaldor-Hicks sense. Nevertheless, the current population of Elephant in Sri Lanka is Kaldor-Hicks preferable to having none. (C) 2003 Elsevier B.V. All rights reserved.
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the net benefit of saving the Asian Elephant a policy and contingent valuation study
Research Papers in Economics, 2003Co-Authors: Ranjith Bandara, Clement A TisdellAbstract:Reports results from a contingent valuation survey of willingness to pay for the conservation of the Asian Elephant of a sample of urban residents living in three selected housing schemes in Colombo, the capital of Sri Lanka. Face–to–face surveys were conducted using an interview schedule. A non-linear logit regression model is used to analyse the respondents’ responses for the payment principle questions and to identify the factors that influence their responses. We investigate whether urban residents’ willingness to pay for the conservation of Elephants is sufficient to compensate farmers for the damage caused by Elephants. We find that the beneficiaries (the urban residents) could compensate losers (the farmers in the areas affected by human–Elephant conflict) and be better off than in the absence of Elephants in Sri Lanka. Therefore, there is a strong economic case for the conservation of the wild Elephant population in Sri Lanka. However, we have insufficient data to determine the optimal level of this Elephant population in the Kaldor-Hicks sense. Nevertheless, the current population of Elephant in Sri Lanka is Kaldor-Hicks preferable to having none.
