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11.
奠基者效应对海南坡鹿迁地保护种群遗传多样性的影响 总被引:4,自引:0,他引:4
在迁地保护中,奠基者效应通常会导致新建种群与源种群的遗传分化,并使新建种群的遗传多样性低于源种群。海南坡鹿(Cervuseldi hainanus)是世界濒危种,野生种群仅分布在中国海南岛。由于栖息地破坏和过度狩猎,至20世纪70年代,这个物种仅剩26只,已经濒临绝灭,被列为国家一级保护动物。自1976年开始对海南坡鹿实施就地保护和迁地保护,该种群的数量从最初的26只增加到1600多只。本文采用10个微卫星位点对一个源种群(大田种群)和5个迁地种群(邦溪、甘什岭、枫木、金牛岭、文昌种群)的遗传多样性进行检测,结果发现6个种群的遗传多样性水平均较低(He≈0·3);5个迁地种群分别有1、3或5个单态位点,大田种群无单态位点;邦溪种群与大田种群遗传分化显著,而甘什岭种群与大田种群的遗传分化不显著。结果表明,奠基者效应导致种群的遗传多样性水平较低,并且对于不同迁地种群,影响也不相同。造成这些差异的因素有建群者数量、引种方式和建群种群的结构。该研究为今后在海南岛建立新的海南坡鹿迁地种群提供建议和参考,同时也为其他濒危物种的迁地保护提供理论指导。 相似文献
12.
ANDREA E. BARBKNECHT W. SUE FAIRBANKS JARED D. ROGERSON ERIC J. MAICHAK LAURA L. MEADOWS 《The Journal of wildlife management》2009,73(1):144-148
ABSTRACT We assessed success of vaginal implant transmitters (VITs), deployed in 198 elk (Cervus elaphus nelsoni), in locating elk calving sites in western Wyoming, USA, in 2006–2007. We identified 60.3% of expelled VIT locations as definite or probable event markers and an additional 21.8% as possible event markers. Failure rate for VITs was 10.6%, and we found an additional 7.3% in improbable or impossible parturition sites. Vaginal implant transmitters were effective in locating calving and abortion sites and will facilitate definition of parturition habitat selection and parturition ranges of specific subpopulations. 相似文献
13.
Louise Rosson 《New Zealand journal of zoology.》2013,40(4):267-269
Abstract The Otago Regional Council could perhaps be renamed the Otago Rabbit Council. Some 35% of our budget—$8 million—goes annually towards dealing with rabbits, which certainly meet the definition of a pest (an animal which “disrupts management objectives” and lives at a population density exceeding “what society considers to be an acceptable level”). We can only hope that the day will come when we can, with confidence, say that the problem is being solved and when public and private financial inputs into rabbit control can be set at a far more reasonable level. 相似文献
14.
Giuseppe Puddu Luigi Maiorano Alessandra Falcucci Fabio Corsi Luigi Boitani 《Biodiversity and Conservation》2009,18(8):2001-2016
The Corsican red deer, a sub-species of the European red deer endemic to Sardinia and Corsica, was abundant on both islands
at the beginning of 1900. It went extinct in Corsica and reached a minimum of 100 individuals in Sardinia by 1970. Numbers
have recovered in Sardinia with more than 1,000 rutting males now present; in the 1980s the deer was reintroduced to Corsica,
but the Sardinian population remains fragmented. We developed a potential distribution model in Sardinia using Ecological
Niche Factor Analysis. To assess the deer’s protection status we compared the model with the existing and proposed conservation
areas and investigated different conservation scenarios in relation to the expansion of its current range and resilience to
future changes in land use and predicted trends of desertification. According to our results over 70% of Sardinia is unsuitable
to the deer, nevertheless high suitability areas (Mediterranean forests away from main roads) are available throughout the
island, particularly in the south and in the central-eastern part. Existing protected areas do not provide for the conservation
of the deer but public owned forests, where hunting is prohibited, extend some level of protection, and the protected areas
proposed by the Regional administration, if implemented, will be increasing this protection. Three main areas have emerged
as conservation priorities to guarantee adequate conservation potential in the future. Our approach provides valuable data
to inform conservation policy, and could be easily replicated in other parts of the Mediterranean. 相似文献
15.
新疆塔里木马鹿粪便激素含量季节性变化的初步研究 总被引:3,自引:0,他引:3
目的:检测雄性塔里木马鹿的睾酮,雌鹿的雌二醇、雌三醇、孕酮等粪便激素含量,并比较不同月份之间的变化。方法:利用放射免疫分析法(RIA)在且末和尉犁县马鹿场采集塔里木马鹿粪便,检测了2004年2~12月间塔里木马鹿粪便中的激素水平。结果:粪便性激素水平有明显的季节变化(P<0.05)。雄鹿粪便睾酮水平月间差异显著(P<0.05),浓度在8月有2个高峰。雌鹿粪便雌二醇在3月和6月有2个高峰;粪便孕酮水平在3月有2个高峰,在8月有1个高峰;雌三醇差异不显著,但4月的最高值也显著高于其他各时间点(P<0.05)。结论:利用动物粪便研究激素具有对保护动物完全无伤害、材料收集容易等优点,并且有助于评估动物青春期的健康状况、判断动物排卵方式、早孕检查、产前预测等,因而是目前研究野生珍稀动物性激素的一种较为理想的方法。 相似文献
16.
17.
Food habits of sika deer on the Boso Peninsula,central japan 总被引:6,自引:0,他引:6
The rumen contents of sika deer (Cervus nippon Temminck) on the Boso Peninsula, central Japan, were analyzed to identify local, sexual and age-specific differences in food
habits. Graminoids and woody plants were the primary foods throughout the year. In winter, the use of evergreen broad leaves
increased. The food habits of sika deer on Boso Peninsula were intermediate between those of populations inhabiting northern
and southern Japan. Acorns, mainlyLithocarpus edulis Nakai, were consumed in fall and winter with a peak in October. Since the availability of acorns is not influenced by foraging
in previous years, it can be regarded as a stable food supply and hence may be important for deer on the Boso Peninsula. The
local difference between the Amatsukominato (AT) area, having a large plantation ofLithocarpus producing acrons, and the Kamogawa-Katsuura (KK) area, having a small plantation ofLithocarpus, was recognized; seeds and fruit were consumed more in AT than in KK in fall and winter. Males consumed more seeds and fruit
than females at both sites in fall. This can be attributed to sexual differences in nutritional requirement. 相似文献
18.
海南坡鹿雄鹿发情期的吼叫行为及其在繁殖中的意义 总被引:9,自引:0,他引:9
1998年 3~ 5月期间 ,于海南省大田国家级自然保护区的养鹿场内共记录到 7只半野生海南坡鹿(Cervuseldihainanus)雄鹿发情期 4 6次吼叫 ,但未见到雌鹿发出吼叫的现象。记录到的所有吼叫均由年龄大于4 5岁的雄鹿发出 ,其中 1只雄鹿的吼叫达 2 2次 ,占 4 7 8%。雄鹿的吼叫由连续的 3~ 13声组成 ,整个吼叫过程持续 9~ 2 3s ,吼叫频率为 [3 4 74± 6 90 ( 2 5 ) ]声 /min。雄鹿每次的吼叫声数及持续时间存在显著的个体差异。雄鹿的吼叫在白天和夜间均能听见 ,但主要发生于 8:0 0~ 9:5 9及 17:0 0~ 17:5 9两个时间段。吼叫是雄鹿繁殖活动的一个表现指标 ,它与雄鹿的蹭角、泥浴、争斗胜利、交配成功或追逐发情雌鹿等优势行为显著正相关。因此 ,我们认为吼叫是雄鹿发情行为中的一种优势炫耀行为 ,具有明显的繁殖意义。 相似文献
19.
Joseph Yarkovich Jessica L. Braunstein Jennifer M. Mullinax Joseph D. Clark 《The Journal of wildlife management》2024,88(2):e22522
In 2001 and 2002, 52 elk (Cervus canadensis; 21 males, 31 females), originally obtained from Elk Island National Park, Alberta, Canada, were transported and released into Cataloochee Valley in the northeastern portion of Great Smoky Mountains National Park (GRSM, Park), North Carolina, USA. The annual population growth rate (λ) was negative (0.996, 95% CI = 0.945–1.047) and predation by black bears (Ursus americanus) on elk calves was identified as an important determinant of population growth. From 2006 to 2008, 49 bears from the primary elk calving area (i.e., Cataloochee Valley) were trapped and translocated about 70 km to the southwestern portion of the Park just prior to elk calving. Per capita recruitment (i.e., the number of calves produced per adult female that survive to 1 year of age) increased from 0.306 prior to bear translocation (2001–2005) to 0.544 during years when bears were translocated (2006–2008) and λ increased to 1.118 (95% CI = 1.096–1.140). Our objective was to determine whether per capita calf recruitment rates after bear removal (2009–2019) at Cataloochee were similar to the higher rates estimated during bear removal (i.e., long-term response) or if they returned to rates before bear removal (i.e., short-term response), and how those rates compared with recruitment from portions of our study area where bears were not relocated. We documented 419 potential elk calving events and monitored 129 yearling and adult elk from 2001 to 2019. Known-fate models based on radio-telemetry and observational data supported calf recruitment returning to pre-2006 levels at Cataloochee (short-term response); recruitment of Cataloochee elk before and after bear relocation was lower (0.184) than during bear relocation (0.492). Recruitment rates of elk outside the removal area during the bear relocation period (0.478) were similar to before and after rates (0.420). In the Cataloochee Valley, cause-specific annual calf mortality rates due to predation by bears were 0.319 before, 0.120 during, and 0.306 after bear relocation. In contrast, the cause-specific annual mortality rate of calves in areas where bears were not relocated was 0.033 after the bear relocation period, with no bear predation on calves before or during bear relocation. The mean annual population growth rate for all monitored elk was 1.062 (95% CI = 0.979–1.140) after bear relocation based on the recruitment and survival data. Even though the effects of bear removal were temporary, the relocations were effective in achieving a short-term increase in elk recruitment, which was important for the reintroduction program given that the elk population was small and vulnerable to extirpation. 相似文献
20.
Seasonal changes in the composition of the diet of the sika deer population in the Shiranuka Hills, eastern Hokkaido, in 1998 were determined by fecal analyses. The deer were dependent on Sasa nipponica, a dwarf bamboo, throughout the year, particularly in winter when it accounted for as much as 77.7% of the diet. It accounted for 33.1% and 45.6% in spring and summer, respectively, and this decreased to 12.2% in autumn. Besides S. nipponica, all the graminoid categories accounted for large amounts (66–96.7%), while dicotyledonous plants accounted for little (3–8%) except in autumn when they accounted for 31%. The strong dependence of the Shiranuka population on graminoids was different from other Hokkaido deer populations, for example the population from Ashoro/Onbetsu and the extremely high density population on Nakanoshima Island. In spite of these differences, food for all Hokkaido sika deer was poor in winter. Along the north–south geographical cline in the food composition of sika deer along the Japanese archipelago, the Shiranuka population was positioned as a grazer type, in contrast to the southern populations. However, it is important to note that variations are great among local populations in Hokkaido. 相似文献