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1.
Ecol Appl ; 26(7): 2347-2357, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27755732

RESUMO

While trophy hunting provides revenue for conservation, it must be carefully managed to avoid negative population impacts, particularly for long-lived species with low natural mortality rates. Trophy hunting has had negative effects on lion populations throughout Africa, and the species serves as an important case study to consider the balance of costs and benefits, and to consider the effectiveness of alternative strategies to conserve exploited species. Age-restricted harvesting is widely recommended to mitigate negative effects of lion hunting, but this recommendation was based on a population model parameterized with data from a well-protected and growing lion population. Here, we used demographic data from lions subject to more typical conditions, including source-sink dynamics between a protected National Park and adjacent hunting areas in Zambia's Luangwa Valley, to develop a stochastic population projection model and evaluate alternative harvest scenarios. Hunting resulted in population declines over a 25-yr period for all continuous harvest strategies, with large declines for quotas >1 lion/concession (~0.5 lion/1,000 km2 ) and hunting of males younger than seven years. A strategy that combined periods of recovery, an age limit of ≥7 yr, and a maximum quota of ~0.5 lions shot/1,000 km2 yielded a risk of extirpation <10%. Our analysis incorporated the effects of human encroachment, poaching, and prey depletion on survival, but assumed that these problems will not increase, which is unlikely. These results suggest conservative management of lion trophy hunting with a combination of regulations. To implement sustainable trophy hunting while maintaining revenue for conservation of hunting areas, our results suggest that hunting fees must increase as a consequence of diminished supply. These findings are broadly applicable to hunted lion populations throughout Africa and to inform global efforts to conserve exploited carnivore populations.


Assuntos
Distribuição Animal , Conservação dos Recursos Naturais/métodos , Regulamentação Governamental , Leões , África , Animais , Extinção Biológica , Licenciamento , Masculino , Controle da População , Fatores de Tempo
3.
Vector Borne Zoonotic Dis ; 13(9): 643-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23805791

RESUMO

Disease transmission within and among wild and domestic carnivores can have significant impacts on populations, particularly for threatened and endangered species. We used serology to evaluate potential exposure to rabies virus, canine distemper virus (CDV), and canine parvovirus (CPV) for populations of African lions (Panthera leo), African wild dogs (Lycaon pictus), and spotted hyenas (Crocuta crocuta) in Zambia's South Luangwa National Park (SLNP) and Liuwa Plain National Park (LPNP) as well as community lands bordering these areas. In addition, domestic dogs in the study region were evaluated for exposure to CDV and rabies. We provide the first comprehensive disease exposure data for these species in these ecosystems. Twenty-one lions, 20 hyenas, 13 wild dogs, and 38 domestic dogs were sampled across both regions from 2009 to 2011. Laboratory results show 10.5% of domestic dogs, 5.0% of hyenas, and 7.7% of wild dogs sampled were positive for CDV exposure. All lions were negative. Exposure to CPV was 10.0% and 4.8% for hyenas and lions, respectively. All wild dogs were negative, and domestic dogs were not tested due to insufficient serum samples. All species sampled were negative for rabies virus neutralizing antibodies except lions. Forty percent of lions tested positive for rabies virus neutralizing antibodies. Because these lions appeared clinically healthy, this finding is consistent with seroconversion following exposure to rabies antigen. To our knowledge, this finding represents the first ever documentation of rabies virus neutralizing antibodies consistent with rabies exposure that did not lead to clinical disease in free-ranging African lions from this region. With ever-increasing human pressure on these ecosystems, understanding disease transmission dynamics is essential for proper management and conservation of these carnivore species.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Cinomose Canina/imunologia , Hyaenidae/virologia , Leões/virologia , Parvovirus Canino/imunologia , Vírus da Raiva/imunologia , Animais , Animais Domésticos , Animais Selvagens , Carnívoros , Cinomose/epidemiologia , Cinomose/virologia , Vírus da Cinomose Canina/isolamento & purificação , Cães , Ecossistema , Humanos , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/virologia , Parvovirus Canino/isolamento & purificação , Raiva/epidemiologia , Raiva/veterinária , Raiva/virologia , Zâmbia/epidemiologia
4.
Rev. biol. trop ; 60(4): 1631-1639, Dec. 2012. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-662236

RESUMO

Black lechwe (Kobus leche smithemani) is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15 000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15 000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000) of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA), only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37) and 81% (n=37) for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of time.


El lechwe negro (Kobus leche smithemani) es un antílope semi-acuático de tamaño medio que en la actualidad se encuentra en la lista roja de la UICN de especies en peligro de extinción y sólo es endémica de la cuenca del Bangweulu de Zambia. Su población ha disminuido considerablemente, de más de 250 000 a 15 000, debido a las inundaciones que se dieron durante el período 1930-1940, lo que llevó al gobierno de Zambia a declarar todos los hábitats del lechwe negro en áreas protegidas estatales, y a establecer estrategias de administración urgentes necesarias para salvar el resto de la población de la extinción. Utilizando los datos retrospectivos, nuestros resultados muestran que la población ha aumentado de 15 000 animales en 1954 a 55 632 en 2009. La población actual se estima en 34.77% (55 632/160 000) de la capacidad de carga de la cuenca del Bangweulu. Aunque el lechwe Negro es una de las 42 especies que se ofrecen para su utilización consuntiva por la Autoridad de Vida Silvestre de Zambia (ZAWA), sólo el 0.12% y 0.08% de la población actual se ha ofrecido para el safari y la caza residente anual para el período 2005-2009, respectivamente. La utilización de la cuota anual se estima en 67% (n=67) y 81% (n=37) para safari de caza y residente, respectivamente. Por lo tanto, los ingresos totales obtenidos de la utilización del lechwe negro son muy bajos contando sólo el 2.1% de los ingresos totales obtenidos de la utilización de la fauna silvestre. Aunque la tendencia actual de la población está mostrando un incremento unitario de 639 animales por año, está todavía muy por debajo de los niveles ideales para la utilización lucrativa. En este estudio, se demuestra que los cambios ecológicos perjudiciales sobre especies de fauna silvestre, puede conducir a su vulnerabilidad y peligro de extinción, y que la recuperación de su capacidad de carga completa puede exigir una cantidad considerable de tiempo.


Assuntos
Animais , Antílopes/classificação , Ecossistema , Espécies em Perigo de Extinção , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Monitoramento Ambiental , Extinção Biológica , Densidade Demográfica , Zâmbia
5.
BMC Vet Res ; 8: 221, 2012 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-23151267

RESUMO

BACKGROUND: In Zambia, the presence of bovine tuberculosis in both wild and domestic animals has long been acknowledged and mutual transmission between them has been predicted without any direct evidence. Elucidation of the circulating Mycobacterium bovis strains at wild and domestic animals interphase area in Zambia, where bovine tuberculosis was diagnosed in wildlife seemed to be important. RESULTS: A PCR identified 15 and 37 M. bovis isolates from lechwe and cattle, respectively. Spoligotype analysis revealed that M. bovis strains from lechwe and cattle in Kafue basin clustered into a major node SB0120, where isolates outside the Kafue basin clustered into different nodes of SB0131 and SB0948. The comparatively higher variety of strains in cattle compared to lechwe elucidated by Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeats analyses are consistent with cattle being the probable source of M. bovis in wild and domestic animals interphase area in Zambia. CONCLUSIONS: These results provide strong evidence of M. bovis strains transfer between cattle and lechwe, with the latter having developed into a sylvatic reservoir host.


Assuntos
Antílopes , Doenças dos Bovinos/epidemiologia , Mycobacterium bovis/isolamento & purificação , Tuberculose Bovina/microbiologia , Animais , Animais Domésticos , Animais Selvagens , Bovinos , Doenças dos Bovinos/microbiologia , Mycobacterium bovis/genética , Reação em Cadeia da Polimerase/veterinária , Tuberculose Bovina/epidemiologia , Zâmbia/epidemiologia
6.
Rev Biol Trop ; 60(4): 1631-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23342517

RESUMO

Black lechwe (Kobus leche smithemani) is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000) of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA), only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37) and 81% (n=37) for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of time.


Assuntos
Antílopes/classificação , Ecossistema , Espécies em Perigo de Extinção , Animais , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Monitoramento Ambiental , Extinção Biológica , Densidade Demográfica , Zâmbia
7.
Vet Med Int ; 2011: 385091, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21776347

RESUMO

Bovine tuberculosis (BTB) is endemic in African buffaloes (Syncerus caffer) in some National Parks in Southern Africa, whilst no studies have been conducted on BTB on buffalo populations in Zambia. The increased demand for ecotourism and conservation of the African buffalo on private owned game ranches has prompted the Zambian Wildlife Authority (ZAWA) and private sector in Zambia to generate a herd of "BTB-free buffaloes" for ex situ conservation. In the present study, 86 African buffaloes from four different herds comprising a total of 530 animals were investigated for the presence of BTB for the purpose of generating "BTB free" buffalo for ex-situ conservation. Using the comparative intradermal tuberculin test (CIDT) the BTB status at both individual animal and herd level was estimated to be 0.0% by the CIDT technique. Compared to Avian reactors only, a prevalence of 5.8% was determined whilst for Bovine-only reactors a prevalence of 0.0% was determined. These results suggest the likelihood of buffalo herds in the Kafue National Park being free of BTB.

8.
Korean J Parasitol ; 49(1): 91-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21461276

RESUMO

We report 2 cases of Thelazia rhodesii infection in the African buffaloes, Syncerus caffer, in Zambia. African buffalo calves were captured from the livestock and wildlife interface area of the Kafue basin in the dry season of August 2005 for the purpose to translocate to game ranches. At capture, calves (n=48) were examined for the presence of eye infections by gently manipulating the orbital membranes to check for eye-worms in the conjunctival sacs and corneal surfaces. Two (4.3%) were infected and the mean infection burden per infected eye was 5.3 worms (n=3). The mean length of the worms was 16.4 mm (95% CI; 14.7-18.2 mm) and the diameter 0.41 mm (95% CI; 0.38-0.45 mm). The surface cuticle was made of transverse striations which gave the worms a characteristic serrated appearance. Although the calves showed signs of kerato-conjunctivitis, the major pathological change observed was corneal opacity. The calves were kept in quarantine and were examined thrice at 30 days interval. At each interval, they were treated with 200 µg/kg ivermectin, and then translocated to game ranches. Given that the disease has been reported in cattle and Kafue lechwe (Kobus lechwe kafuensis) in the area, there is a need for a comprehensive study which aims at determining the disease dynamics and transmission patterns of thelaziasis between wildlife and livestock in the Kafue basin.


Assuntos
Búfalos/parasitologia , Oftalmopatias/veterinária , Infecções por Spirurida/veterinária , Thelazioidea/isolamento & purificação , Animais , Anti-Helmínticos/uso terapêutico , Oftalmopatias/tratamento farmacológico , Oftalmopatias/parasitologia , Infecções por Spirurida/tratamento farmacológico , Infecções por Spirurida/parasitologia , Thelazioidea/fisiologia , Zâmbia
9.
BMC Vet Res ; 6: 29, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20515454

RESUMO

BACKGROUND: In Zambia, translocation of wildlife from National Parks to private owned game ranches demands that only animals free of infectious diseases that could adversely affect the expansion of the wildlife industry should be translocated to game ranches. Sarcoptes mange (Sarcoptes scarbiei) has been involved in the reduction of wildlife populations in some species. RESULTS: Sarcoptes mange (Sarcoptes scarbiei) was detected and eradicated from two herds of African buffalo (Syncerus caffer) calves captured in the Kafue GMA in July 2004 and August 2005. The overall prevalence was estimated at 89.5% (77/86). Sex had no influence on the occurrence and severity of the disease. Of the 86 calves used in the study, 72.1% had good body condition scores, 20.9% were fair and 7.0% were poor. Of the 77 infected calves, 53.2% were mildly infected, 28.6% were moderately and 18.2% were severely infected. Body condition score was correlated to the severity of the infection (r = 0.72, p < 0.000, n = 86) at capture. Eradication of Sarcoptes mites from the entire herd using ivermetcin was dependant on the severity of the infection. The overall ability of ivermectin to clear the infection after the first treatment was estimated at 81.8% (n = 77). It increased to 94.8% and 100% after the second and third treatments respectively. CONCLUSION: This is the first report on the epidemiology and treatment of Sarcoptes mange in African buffaloes in Zambia. This study improves our understanding about Sarcoptes scabiei epidemiology and treatment which will have further applications for the safe animal translocation.


Assuntos
Búfalos , Inseticidas/uso terapêutico , Ivermectina/uso terapêutico , Sarcoptes scabiei , Escabiose/veterinária , Animais , Composição Corporal , Feminino , Masculino , Prevalência , Escabiose/epidemiologia , Zâmbia/epidemiologia
10.
Korean J Parasitol ; 48(1): 67-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20333288

RESUMO

Trypomastogotes of Trypanosoma brucei were detected from 4 asymptomatic kudus (Tragelaphus strepsiceros) on a game ranch located approximately 45 km north east of Lusaka, Zambia. Blood smears examined from 14 wildlife species comprising of the impala (Aepyceros melampus), Kafue lechwe (kobus leche kafuensis), sable antelope (Hippotragus niger), tsessebe (Damaliscus lunatus), warthog (Phacochoerus aethiopicus), puku (Kobus vardoni), zebra (Equus burchelli), waterbuck (Kobus ellipsiprymnus), bushbuck (Tragelaphus scriptus), reedbuck (Redunca arundinum), wilderbeest (Connochaetes taurinus), hartebeest (Alcephelus lichtensteini), African buffalo (Syncerus caffer), and kudu (Tragelaphus strepsiceros) showed that only the kudu had T. brucei. Although game ranching has emerged to be a successful ex-situ conservation strategy aimed at saving the declining wildlife population in the National Parks, our findings suggest that it has the potential of aiding the re-distribution of animal diseases. Hence, there is a need for augmenting wildlife conservation with disease control strategies aimed at reducing the risk of disease transmission between wildlife and domestic animals.


Assuntos
Ruminantes/parasitologia , Trypanosoma brucei brucei/isolamento & purificação , Tripanossomíase/diagnóstico , Animais , Animais Selvagens , Zâmbia
11.
Vet Parasitol ; 166(1-2): 163-6, 2009 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-19733007

RESUMO

A serolocigical survey was conducted for the detection of Theileria parva antibodies in 176 African buffaloes (Syncerus caffer) sampled between 1996 and 2005 in livestock-wildlife interface areas of Zambia. Rhipicephalus appendiculatus, Rhipicephalus species, and Amblyomma variegatum were the most abundant tick species identified on buffaloes. T. parva sero-positives were reported in buffaloes sampled from game management areas at Mlanga and Nanzhila bordering the Kafue National Parks and in the Lochnivar National Park while buffaloes sampled from Lower Zambezi National Park were sero-negative. Given that Game Management Areas serve as interface areas that permit the co-existence of livestock and wildlife in similar ecological habitats our findings suggest that buffaloes could play a significant role in the epidemiology of theileriosis in livestock-wildlife interface areas. Thus far, the disease has only been reported in livestock and is herein being reported in the African buffalo for the first time in Zambia.


Assuntos
Anticorpos Antiprotozoários/sangue , Búfalos/parasitologia , Theileria parva/fisiologia , Theileriose/epidemiologia , Animais , Ixodidae/parasitologia , Ixodidae/fisiologia , Estudos Soroepidemiológicos , Theileriose/imunologia , Theileriose/parasitologia , Infestações por Carrapato/veterinária , Zâmbia/epidemiologia
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