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21.
利用塑料瓶投放诱饵设置诱捕井的办法防治森林害鼠 ,1hm2 设 5 0个诱捕井 (10m× 2 0m ) ,2 4h诱捕率 90 % ,防治效果 90 6 %。 相似文献
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Yong Li Katsutaro Yamamoto Tomonori Hiraishi Katsuaki Nashimoto Hiroyuki Yoshino 《Fisheries Science》2006,72(6):1147-1152
ABSTRACT: A field experiment was conducted in the Matsumae area of Hokkaido, Japan, during June and July 2002, to investigate the effects of different entrance designs on the catch efficiency of fish traps by fishing with commercial traps (entrance inclination angle [α] = 37°; funnel length of entrance [ L f ] = 22 cm) and experimental traps. The experimental traps were of the same size and similar design as commercial traps, with different entrance inclination angles (trap E1: α = 46°; E2: α = 27°; E3: α = 0°; all L f = 22 cm) or funnel lengths (E4: α = 37°, L f = 8 cm). In total, 2200 fish during 200 trap hauls were captured. The catch was significantly higher using both traps E2 and the commercial trap than with trap E3 ( P < 0.05), and the catch of trap E2 was higher than that of the commercial trap. There were no significant differences in mean fish body length or the frequency distributions of body length among trap types (E1, E2, E3 and commercial). The funnel length of the entrance also affected the catch of traps. Trap E4 had significantly higher catches than the commercial trap ( P = 0.04) when traps were deployed for a 1-day soak time. Fish body length frequency distributions did not differ between trap E4 and the commercial trap. The results showed that catch can be greatly affected by trap entrance designs. 相似文献
23.
Thomas D. Dahmer Gui Xiaojie Tian Shurong 《野生动物》2014,(1):19-25
2001—2003年的20个月里,我们在中国湖南省壶瓶山国家级自然保护区内设置了一些触发相机,以确定该地区是否存在华南虎(Pantheratigrisamoyensis)。共设置r3种触发相机,包括TrailMaster(美国)的主动式和被动式相机以及WildlifeTwo(中国深圳)的被动式相机。首先在保护区西部沿着小路和动物足迹放置了一些相机。之后又从2002年开始在保护区东部追加放置了一些相机,这是因为有村民报告在这一区域发生了家畜丢失,发现猫科动物足迹以及听到吼叫声。在2002年5月到2003年12月的20个月期间,共8307个拍摄日,获得6180张照片,其中有1437张包括野生动物(平均每100个拍摄日17张野生动物照片)。合计拍摄到33种野生动物。,野猪(Susscrofa)、红腹锦鸡(Chrysolophuspictu.s)和毛冠鹿(Elaphoduscephalophus)是被拍摄最频繁的物种。既没有拍到虎和其他大型猫科动物,也没有拍到水鹿(Cervusunicolor)这种虎重要的猎物。最频繁被拍摄到的猫科动物是豹猫(Prionailurusbengalensis)。村民偶尔报告的掠走山羊的事件可能是豹(Pantherapardta)造成的,但是不能确定。利用触发相机调查超过1000d没有拍摄到虎,这一充分的证据足以支持该调查区没有虎的结论(d=0.05)。20个月超过8300个拍摄日没有在壶瓶山拍摄到虎,显示该地区没有虎。值得注意的结果是拍到红腹锦鸡、黄喉貂(Martesflavigula)、毛冠鹿和黑熊(Ursusthibetanus)的频率很高。这些物种是中国或国际受保护物种,包括被列为国内受保护物种,或同时列为国际受保护物种,又或者像毛冠鹿这种几乎是未知的物种。壶瓶山国家级自然保护区附近有3个保护区。我们讨论建议将这4个保护区合并为一个更大的保护地域来保护虎及其猎物。并且在此简要地评论了我们使用的3种触发相机的性能。 相似文献
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We tested whether synchronous, long‐term fluctuations in Atlantic bluefin tuna (Thunnus thynnus) trap catches, collected from the ancestral Mediterranean and Atlantic trap fishery, might be related to large‐scale environmental change. Nine time series of trap catches of more than 80 yr long were compared with long time series of three preselected environmental variables, i.e. the North Atlantic Oscillation (NAO), the Length of the Day Index (LOD, a proxy of the atmospheric circulation index) and the temperature. Spectral analyses of trap catches, LOD and temperature displayed similar spectra with peaks at low frequencies, whereas those of the NAO exhibited a broad band spectrum. Regression analyses and tests of correlation did not reveal any clear relationship between trap catches on the one hand and NAO and LOD on the other hand. In contrast, long‐term fluctuations in trap catches appear to be closely and negatively related to long‐term trends in temperature. Underlying processes that could explain such a relationship are discussed, with special focus on changes in migration patterns of the Atlantic bluefin tuna. 相似文献
26.
Geneviève Faille Jean-Pierre Ouellet Réhaume Courtois Claude Dussault 《Biological conservation》2010,143(11):2840-2850
Conservation of forest-dwelling caribou (Rangifer tarandus caribou) is of great concern across most of its range. Anthropogenic disturbances, primarily logging activities, have been identified as the most important cause of caribou decline, although the mechanisms underlying this decline are not fully understood. Caribou commonly display fidelity to calving sites or seasonal ranges, but the potential role of this life-history trait has been largely overlooked in research and conservation planning. This is surprising because sites and ranges with high inter-annual use should have high conservation value. We investigated the relationship between habitat disturbances and home-range fidelity of forest-dwelling caribou across three study sites in Québec, Canada, using a broad range of natural and anthropogenic disturbances. Between 2004 and 2007, we tracked 47 adult female caribou using GPS collars. Home-range fidelity varied between seasons, being higher during calving and summer, and lower during winter. Caribou reduced fidelity following natural and anthropogenic disturbances, the latter having a stronger negative influence. Anthropogenic disturbances had a strong negative impact on home-range fidelity during annual, summer and winter periods, whereas natural disturbance was the dominant factor during calving. Despite this negative influence on fidelity, caribou tended to demonstrate range fidelity even in study sites most impacted by human activities. Habitat disturbances could produce two possible outcomes for caribou conservation: (1) a trend for females to reduce home-range fidelity which could translate into lower calf and female caribou survival through reduced familiarity with food distribution, escape cover and predation risk and (2) a global tendency to maintain range fidelity even in a drastically modified landscape which could turn into an ecological trap, particularly for calves when predation risk increases due to increased black bear density in early successional forests. Taking range fidelity behavior into consideration during forest management planning could direct conservation efforts toward the best available sites and therefore facilitate caribou persistence in managed landscapes. 相似文献
27.
《Journal Of Applied Aquaculture》2013,25(3):65-74
Abstract The Lin coln In dex mark-re cap ture method was eval u ated for its ac cu racy in es ti mat ing the num ber of harvestable yab bies, Cherax de struc tor, in earthen ponds. Where a sin gle re cap ture event was used to es ti mate the pop u la tion, a 3 to 6 day in ter val be tween the re lease and recap ture of marked an i mals tended to pro vide a more re li able es ti mate than a re lease and re cap ture in ter val of 24 hours. Where two re cap ture events were used to pro vide an av er age es ti mate, the method tended to un der es ti mate by 20% low den sity pop u la tions, that had been the sub ject of pre da tion by wa ter birds, whereas those es ti mates de ter mined f o r ponds with higher den si ties of cray fish, where avian piscivores were excluded, tended to be more ac cu rate (±10%). The ap pli ca tion of pop u la tion es ti ma tion as a tool for ar ti fi cial feed-man age ment is dis cussed. 相似文献
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新仓型储粮害虫陷阱检测技术研究及应用 总被引:2,自引:0,他引:2
对新建仓储粮害虫防治及检测中存在的问题进行了讨论。介绍了YC-97型储粮温湿度及害虫监测系统和粮虫陷阱检测检疫技术在新仓型中的应用,并与扦样筛选法的效果进行了比较,提出了以环流熏蒸与其它防治技术相结合的害虫综合防治方法。 相似文献