鸟类的飞翔范围与地面状况有关
文章来源:未知 文章作者:meng 发布时间:2010-09-01 02:23 字体: [ ]  进入论坛
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It may seem like birds have the freedom to fly wherever they like, but researchers at the University of Missouri have shown that what's on the ground has a great effect on where a bird flies. This information could be used by foresters(林木工人) and urban(城市的,市区的) planners to improve bird habitats that would help maintain strong bird populations. "Movement of individuals influences nearly every aspect of biology, from the existence of a single population to interactions within and among species," said Dylan Kesler, assistant professor in fisheries(渔业,渔场) and wildlife at the University of Missouri's School of Natural Resources. "Movement determines where individual birds procreate(生殖) . How they spread across the landscape affects who meets whom, which in turn dictates1(口述,听写) how genes3 are spread."

Kesler has found that non-migrating resident birds tend to travel over forest "corridors," which are areas protected by trees and used by wildlife to travel. Birds choose to travel over forests because they can make an easier escape from predators4(捕食者) as well as find food. Man-made features such as roads, as well as gaps forests from agriculture or rivers, can restrict birds to certain areas. When forests are removed, bird populations become isolated5 and disconnected, which can lead to inbreeding(近亲交配,同系繁殖) and weaker, more disease-prone birds.

Earlier this summer, Kesler and MU graduate student Allison Cox tagged 33 juvenile6 red-bellied woodpeckers(啄木鸟) in Missouri's Mark Twain National Forest. Kesler chose to study the red-bellied woodpecker because the bird lives in the same area year-round and is very loyal to specific sites. The tags used by the researchers enable their team to track the birds' daily flights using radiotelemetry(无线电遥测) and GPS technology. The tags are designed to fall off the birds after four months. The summer and fall months are important because this is when young birds are most active, establishing territories and finding mates, studies say.

The research team also hopes to discover more about natal7(出生的,分娩的) dispersal(分散,传播) , the time interval8 between when a bird moves from where it is hatched to an area where it will breed. Very little is known about what influences natal dispersal.

"In many territorial9 resident birds, natal dispersal is the only time an individual bird makes a substantial movement from one location to another," Kesler said. "Natal dispersal is, therefore, integral to gene2 flow among populations, colonizing10 vacant habitat, inbreeding avoidance and maintaining optimal11 population densities12."

This year's work builds upon research Kesler has been conducting since 2005 on three species of woodpeckers and two Pacific island kingfishers(翠鸟) . The study is funded by a University of Missouri program to encourage new faculty13. Results will be published this fall in conservation-oriented science journals. Results from Kesler's previous research about dispersal appeared in the nation's top ornithological14(鸟类学的) journal, The Auk, and another paper will soon be published in Behavioral Ecology.



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1 dictates d2524bb575c815758f62583cd796af09     
n.命令,规定,要求( dictate的名词复数 )v.大声讲或读( dictate的第三人称单数 );口授;支配;摆布
参考例句:
  • Convention dictates that a minister should resign in such a situation. 依照常规部长在这种情况下应该辞职。 来自《简明英汉词典》
  • He always follows the dictates of common sense. 他总是按常识行事。 来自《简明英汉词典》
2 gene WgKxx     
n.遗传因子,基因
参考例句:
  • A single gene may have many effects.单一基因可能具有很多种效应。
  • The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
3 genes 01914f8eac35d7e14afa065217edd8c0     
n.基因( gene的名词复数 )
参考例句:
  • You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因,所以能够活得很长。 来自《简明英汉词典》
  • Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
4 predators 48b965855934a5395e409c1112d94f63     
n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面)
参考例句:
  • birds and their earthbound predators 鸟和地面上捕食它们的动物
  • The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
5 isolated bqmzTd     
adj.与世隔绝的
参考例句:
  • His bad behaviour was just an isolated incident. 他的不良行为只是个别事件。
  • Patients with the disease should be isolated. 这种病的患者应予以隔离。
6 juvenile OkEy2     
n.青少年,少年读物;adj.青少年的,幼稚的
参考例句:
  • For a grown man he acted in a very juvenile manner.身为成年人,他的行为举止显得十分幼稚。
  • Juvenile crime is increasing at a terrifying rate.青少年犯罪正在以惊人的速度增长。
7 natal U14yT     
adj.出生的,先天的
参考例句:
  • Many music-lovers make pilgrimages to Mozart's natal place.很多爱好音乐的人去访问莫扎特的出生地。
  • Since natal day,characters possess the visual elements such as dots and strokes.文字从诞生开始便具有了点画这样的视觉元素。
8 interval 85kxY     
n.间隔,间距;幕间休息,中场休息
参考例句:
  • The interval between the two trees measures 40 feet.这两棵树的间隔是40英尺。
  • There was a long interval before he anwsered the telephone.隔了好久他才回了电话。
9 territorial LImz4     
adj.领土的,领地的
参考例句:
  • The country is fighting to preserve its territorial integrity.该国在为保持领土的完整而进行斗争。
  • They were not allowed to fish in our territorial waters.不允许他们在我国领海捕鱼。
10 colonizing 8e6132da4abc85de5506f1d9c85be700     
v.开拓殖民地,移民于殖民地( colonize的现在分词 )
参考例句:
  • The art of colonizing is no exception to the rule. 殖民的芸术是? 有特例的。 来自互联网
  • A Lesson for Other Colonizing Nations. 其它殖民国家学习的教训。 来自互联网
11 optimal zmDzhM     
adj.最适宜的;最理想的;最令人满意的
参考例句:
  • What is the optimal mix of private and public property rights in natural resources?私人和国家的自然资源产权的最适宜的组合是什么?
  • Optimal path planning is a key link for the sailing contest.帆船最优行驶路径规划是帆船比赛取胜的关键环节。
12 densities eca5c1ea104bef3058e858fe084fb6d0     
密集( density的名词复数 ); 稠密; 密度(固体、液体或气体单位体积的质量); 密度(磁盘存贮数据的可用空间)
参考例句:
  • The range of densities of interest is about 3.5. 有用的密度范围为3.5左右。
  • Densities presumably can be probed by radar. 利用雷达也许还能探测出气体的密度。
13 faculty HhkzK     
n.才能;学院,系;(学院或系的)全体教学人员
参考例句:
  • He has a great faculty for learning foreign languages.他有学习外语的天赋。
  • He has the faculty of saying the right thing at the right time.他有在恰当的时候说恰当的话的才智。
14 ornithological 05fff1359f2d1b1409fd1725f6f8e5c7     
adj.鸟类学的
参考例句:
  • Is there an ornithological reason for keeping them in separate cages? 用独立的笼子养鸟,有什么鸟类学的原因吗? 来自电影对白
  • Mere amateurs in 2009 will make ornithological history in China by discovering birds unknown to science. 在即将来临的2009年里,中国鸟类学史大概会由不打眼的业余人士通过发现未知的鸟类而刷新。 来自互联网
TAG标签: population birds fly
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