Reproductive biology and management of captive black-footed ferrets (Mustela nigripes)

A captive breeding program is being conducted with black-footed ferrets (Mustela nigripes), an endangered species. Results of 5 years of study are reported. Simple, but specialized, nontraumatic handling techniques allowed assessment of reproductive status with minimal stress, which was important in breeding management. Black-footed ferrets are sexually mature and may successfully reproduce in their 1st year. Proestrus lasts approximately 2-3 weeks. Duration of estrus in unbred females was 32–42 days; females usually bred within 20 days. Most breeding activity occurred during April. Mean gestation length was 42.7 days (±0.7, range 42–45 days), litter size averaged 3.0 kits (±1.4, range 1–6 kits), and weaned kits/litter averaged 2.4 (±1.7, range 1–6 kits). Weaning rate of kits was 80%. Sex ratio of kits was essentially 1:1. Productivity was greatest among females ?3 years of age. Rapid expansion of the captive population is possible and will be important for genetic management of the species and for achieving the primary goal of the recovery program, which is to return black-footed ferrets to the wild.     

Ecology of spawning humpback chub, Gila cypha, in the Little Colorado River near Grand Canyon, Arizona

The morphologically unique and endangered humpback chub, Gila cypha, is found in canyon-bound reaches of the Colorado River and its tributaries. Now limited to six isolated reproducing populations, this species is believed to have been once distributed over a large portion of the mainstem river. Because the species inhabits remote canyon areas, little is known about its spawning ecology. The largest remaining population occurs in the lower Little Colorado River (LCR) near Grand Canyon, where we conducted a three-year study of spawning ecology during spring (March-June) 1993–1995. We analyzed seasonal patterns of movement, population density, relative condition, spawning scores, and frequency of ripe condition and fin abrasions and compared these data with seasonal discharge and water temperature to determine spawning phenology and ecology. Spawning commenced in late March, peaked in mid-April, and waned in mid-May. A high proportion of males remained ripe over this period, whereas ripe females were relatively abundant only in April. Increased densities of adult fish in March-April and rapid declines in May-June coupled with recaptures of 18.4% of these adults in the Colorado River suggest that a portion of the population migrated from the Colorado River into the LCR to spawn and then returned. Ripe males aggregated in areas of complex habitat structure with high angular variation in bottom profiles (matrix of large boulders, travertine masses combined with chutes, runs and eddies, 0.5–2.0 m deep) and were associated with deposits of clean gravel. Ripe females appeared to move to these male aggregations to spawn. Near-spawning (including gravid) females and non-spawning fish used similar habitats and were segregated but close (< 50 m) to habitats occupied by aggregations of ripe males. Abrasions on anal and lower caudal fins of males and females suggest that spawning involves contact with gravel substrates, where semi-adhesive eggs are deposited and fertilized. The findings of this study should aid recovery efforts for humpback chub by identifying spawning habitat within the historic distributional range where additional spawning stocks could be established.     

Biological characteristics of European Atlantic sturgeon, Acipenser sturio, as the basis for a restoration program in France

The European Atlantic Sturgeon, Acipenser sturio, has received increased attention in France because of population declines due to overfishing and deterioration of spawning grounds. Conservation of this species requires many actions, including publicizing the necessity to protect this fish and its habitats, investigations on catches and probable spawning grounds, and on artificial reproduction, which is still in an experimental stage. During its sea life, European Atlantic sturgeon occur from the Bay of Biscay to the Bristol Channel and North Sea. Presently, the number of young fish in the Gironde Estuary during summertime is low and the population has a unimodal age structure. At the time this paper was written, the last recorded reproduction of sturgeon in the Gironde system occurred in 1988 (new evidence of reproduction was discovered in 1995). Growth of young fish from the 1988 cohort was faster than that previously determined for others cohorts. Over our study period (1980–1994), the availability of wild broodfish declined. Successful artificial reproduction of wild-caught females requires an optimal physiological state; any delay decreases their reproductive potential. Acclimatization of wild-caught juveniles to fresh water was most successful when fish were transported and held upon arrival in low salinity water. For such wild-caught juveniles, the first food intake usually occurs several months after capture, but remains irregular. These findings will be used to improve ongoing efforts to restore A. sturio.     

列入《濒危野生动植物物种国际贸易公约》附录的物种的新标准

ＣＩＴＥＳ（濒危野生动植物国际贸易公约）是一个通过控制贸易的方法来维护物种生存及其持续利用的国际法规,其附录中所列的物种是重点管理的对象,主要根据现有的Ｂｅｒｎｅ标准来确定。但是,长期的实践证明,它已不能满足实际的需要。１９９２年６月ＣＩＴＥＳ常务委员会要求世界保护联盟协助制定一个简明、实用、科学和客观的新标准,本文对此作一简介和讨论。     

Population genetic structure of Monimopetalum chinense (Celastraceae), an endangered endemic species of eastern China

BACKGROUND AND AIMS: Monimopetalum chinense (Celastraceae) standing for the monotypic genus is endemic to eastern China. Its conservation status is vulnerable as most populations are small and isolated. Monimopetalum chinense is capable of reproducing both sexually and asexually. The aim of this study was to understand the genetic structure of M. chinense and to suggest conservation strategies. METHODS: One hundred and ninety individuals from ten populations sampled from the entire distribution area of M. chinense were investigated by using inter-simple sequence repeats (ISSR). KEY RESULTS: A total of 110 different ISSR bands were generated using ten primers. Low levels of genetic variation were revealed both at the species level (Isp=0.183) and at the population level (Ipop=0.083). High clonal diversity (D = 0.997) was found, and strong genetic differentiation among populations was detected (49.06 %). CONCLUSIONS: Small population size, possible inbreeding, limited gene flow due to short distances of seed dispersal, fragmentation of the once continuous range and subsequent genetic drift, may have contributed to shaping the population genetic structure of the species.     

Nonsurgical embryo transfer in the scimitar-horned oryx (Oryx dammah): Birth of a live offspring

The objective of this project was to determine if modifications of methods of estrous synchronization, superovulation, embryo recovery, and transfer used successfully in other ungulates, both domestic and nondomestic, could be applied to scimitar-horned oryx (Oryx dammah). Donors were two parous females and recipients were one parous and two nulliparous females that were given a total of two cloprostenol injections at an interval of 0 and 13 or 12 days, respectively. Donors were treated with follicle-stimulating hormone (FSH-P, Schering, Kenilworth, NJ) b.i.d. for 4 days and placed with a fertile male. Seven days after the last FSH-P injection, nonsurgical uterine lavages were performed on both donors. One good-quality embryo at the morula stage was recovered and nonsurgically transferred into the right uterine horn of the parous recipient. A healthy female calf born at 247 days post-transfer represents the first known live birth of scimitarhorned oryx following embryo transfer. These results provide additional evidence that estrous synchronization and embryo transfer techniques used in other ungulates can be applied to endangered antelopes such as the scimitar-horned oryx.     

Training in zoo biology,captive breeding,and conservation

Different types of training in zoo biology, captive breeding, and conservation are discussed and the availability of a variety of programs documented. Emphasis is given to the need for more training in general, and especially for less-developed countries where zoos have much potential yet to be realized. The aims, structure, content, and impact of the Jersey Wildlife Preservation Trust's International Training Program are examined.     

Population structure of Hylobates concolor in Bawanglin Nature Reserve,Hainan, China

The Hainan gibbon continues to survive in Bawanglin Nature Reserve in four social groups totalling 21 individuals. Twelve births have occurred since 1982, and 11 of these individuals survive in 1989. Only three of these 12 births have been females, however. The total female population consists of 6 adult females, two of which are at least 19 years old, and three juvenile females born since 1985. Two of the four social groups have only one adult female each and no juvenile females. All four groups are well protected, but their survival is precarious.     

关于物种濒危等级标准之探讨--对IUCN物种濒危等级的思考

为了保存地球上的生物多样性,我们需要根据物种的种群数量与分布、种群数量波动与分布区下降速率来评定濒危物种的濒危等级,并针对物种的濒危等级提出具体的保护措施。1994年11月,IUCN第40次理事会会议正式通过了经过修订的Mace-Lande物种濒危等级标准作为IUCN物种濒危等级标准。IUCN濒危物种红色名录虽然不是国际法和国家法律,但是对于政府间组织、非政府组织的保护决策以及各国的自然法律法规的制定有着深远的影响,在保护生物学理论研究中也发挥了一定作用。我们在研究制定中国水生野生生物濒危等级标准时发现,如果直接应用IUCN物种濒危等级标准评定水生野生生物濒危等级将存在一些问题。如：(1)如何区别对待那些本来就数量稀少、分布区狭窄的物种和那些由于人类活动而导致其种群数量与生境面积急剧下降的物种?(2)不同的动物类群能否应用同一濒危标准尺度?(3)如何区别对待物种边缘分布区和核心分布区的种群数量与密度的差异?(4)如何处理种群的局部灭绝、局部濒危?(5)一些濒危物种在野生环境中濒危,但是这些物种可以人工繁殖,如何处理可以人工繁殖的濒危物种?(6)如果没有种群与栖息地的精确历史资料和统计数据,怎样应用物种的濒危标准评估其濒危等级?在实践中,我们针对这些问题提出了解决方案。考虑与国际流行的IUCN物种濒危等级标准接轨,我们提出来一个由“无危”、“值得关注”、“受胁”、“濒危”和“灭绝”等5个级构成的濒危等级系统,其中“值得关注”、“受胁”、“濒危”又分为“一般”与“高度”两个亚等级。我们提出应区分“生态濒危物种”、“进化濒危物种”;对于不同生物类群,应区分物种的生活史对策,制定不同生活史物种的濒危标准。对于r-对策物种,引入“经济灭绝”这一等级,将这一等级对应于“受胁”等级,以解决缺少物种数量的统计数据和历史数据这一难题;区别对待特有物种,将其濒危等级提升一等;引进集合种群(metapopulation)概念,将集合种群的局域种群(local population)作为“个体”对待。     

Plantlet regeneration from mature embryos of Juniperus cedrus

A protocol is described for plantlet regeneration using embryonic explants of Juniperus cedrus Webb & Berth. An average of 6 adventitious buds were induced on whole excised embryos cultured for 15 days on Quoirin and LePoivre (QP) half-strength medium supplemented with 5 M N⁶-benzyladenine. For bud development, explants were transferred to phytohormone-free 1/2 QP medium. For shoot elongation, explants were cultured on 1/2 QP with 0.05% activated charcoal and 2% sucrose. Adventitious shoots were rooted successfully in peat-vermiculite-perlite (1:1:1) moistened with 1/4 QP containing 1% sucrose and 5 M -napthaleneacetic acid, pH 5.0. Axillary shoots elongated spontaneously in culture from leaf axils.Abbreviations AC activated charcoal - BA N⁶-benzyladenine - NAA -naphthaleneacetic acid - QP Quoirin & LePoivre - SH Schenk & Hildebrandt