Navigation Links
Threatened birds may be rarer than geographic range maps suggest
Date:12/10/2007

Geographic range maps that allow conservationists to estimate the distribution of birds may vastly underestimate the actual population size of threatened species and those with specific habitats, according to a study published online this week in the journal Conservation Biology.

Our study found that species ranges in general tend to get overestimated, but that this trend is particularly pronounced for birds that are threatened, rely on specialized diets or have small habitats, said Walter Jetz, an assistant professor of biological sciences at UC San Diego and the lead author of the study, which will appear in the February issue of the printed journal. This suggests that many threatened species of birds may be even rarer than we believe and are in greater danger of going extinct.

Our findings indicate that the ranges of most vulnerable bird species are experiencing the highest overestimation, thereby painting a rosier picture of their distributions than is actually the case, said Cagan Sekercioglu, a senior research scientist at Stanford University and a co-author of the study. This suggests that the conservation status of many narrow-ranging, specialized and threatened bird species may be worse than we think.

Jetz, Sekercioglu and James E.M. Watson of Britains Oxford University evaluated geographic range overestimation and its potential ecological causes for 1,158 bird species across 4,040 well-studied survey locations in Australia, North America and Southern Africa. Comparing the range maps with actual bird surveys, such as those conducted by the Audubon Society, the scientists found that most species actually occur in only 40 to 70 percent of the range suggested by their range maps. In other words, these birds are not actually found in 30 to 60 percent of their supposed range.

The scientists also found range overestimation increases for species with smaller ranges and with more specialized dietary and habitat requirements
'/>"/>

Contact: Kim McDonald
kmcdonald@ucsd.edu
858-534-7572
University of California - San Diego
Source:Eurekalert

Page: 1 2 3

Related biology news :

1. Freshwater supplies threatened in central Pacific
2. Smithsonian scientists working to save microscopic threatened species
3. Research shows loggerhead sea turtles threatened by small-scale fishing operations
4. New, rare and threatened species discovered in Ghana
5. Food source threatened by carbon dioxide
6. Savanna habitat drives birds, and perhaps others, to cooperative breeding
7. Uncertainty drives the evolution of cooperative breeding in birds
8. A dog in the hand scares birds in the bush
9. City birds better than rural species in coping with human disruption
10. Do migratory birds see the magnetic field?
11. LSU professor studies army-ant-following birds

Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/24/2009)...upus Research Institute (LRI) today named 12 new g...6 million, recognize innovative work across a broa...r their creativity, novelty, and potential to driv...t, and cure the complex disease of systemic lupus....d lupus researchers across the nation and include ...
(Date:11/24/2009)...ger and the American College of Medical Toxicology... the publication of the Journal of Medical Toxico...inning in March 2010. It was previously published... Journal of Medical Toxicology , an international... the science and practice of medical toxicology. ...
(Date:11/24/2009)... release is available in Spanish . , The pr... levels of inflammatory substances in the blood, h... shown by a research project of the University of ...cientist at the School of Pharmacy. , The projec... in relation to the control of body weight and inf...
Breaking Biology News(10 mins):Lupus Research Institute announces 2009 novel research grants 2Lupus Research Institute announces 2009 novel research grants 3Springer and the American College of Medical Toxicology to work together 2It can be predicted the reaction obese patients will have to a diet 2US FDA Approves Extavia 28R 29 the First in a New Portfolio of Planned MS Therapies from Novartis to Help Patients with this Devastating Disease 4853 1US FDA Approves Extavia 28R 29 the First in a New Portfolio of Planned MS Therapies from Novartis to Help Patients with this Devastating Disease 4853 2US FDA Approves Extavia 28R 29 the First in a New Portfolio of Planned MS Therapies from Novartis to Help Patients with this Devastating Disease 4853 3US FDA Approves Extavia 28R 29 the First in a New Portfolio of Planned MS Therapies from Novartis to Help Patients with this Devastating Disease 4853 4US FDA Approves Extavia 28R 29 the First in a New Portfolio of Planned MS Therapies from Novartis to Help Patients with this Devastating Disease 4853 5US FDA Approves Extavia 28R 29 the First in a New Portfolio of Planned MS Therapies from Novartis to Help Patients with this Devastating Disease 4853 6US FDA Approves Extavia 28R 29 the First in a New Portfolio of Planned MS Therapies from Novartis to Help Patients with this Devastating Disease 4853 7New biofactories produce rare healing substances in the endangered Devils claw plant 54597 1New biofactories produce rare healing substances in the endangered Devils claw plant 54597 2New biofactories produce rare healing substances in the endangered Devils claw plant 54597 3Newly found DNA catalysts cleave DNA with water molecule 9589 1Newly found DNA catalysts cleave DNA with water molecule 9589 2
...in a key brain protein known to underlie a form of...nting the normal growth and branching of neurons, ...alfunction of the protein made by mutant forms of ...ultimately leading to their death. The loss of dop...y of PD, and loss of connections among such neuron...
... simple stream of one-letter characters in the hum...de. In order to decipher this level of architectu...ental and algorithmic methods to detect copy numbe...duplications of DNA segments. These technologies-...were used to create the first comprehensive map of...
...g reasons behind the dramatic increase in testicul...ong 15-to-35-year-old Caucasian men, is the focus ...tute (NCI) grant to Yale Public Health researcher ... for unknown reasons and this study will provide i...netic and other risk factors,?said Zheng, professo...
Other Biology News:Parkinson's mutation stunts neurons 2New technology used to construct the first map of structural variation in the human genome 2
(Date:11/24/2009)...o also Visit Detroit , (V...French Ambassador for International Investment, an... , , , ,What: Ambassador Appia is available to me...atives adopted by France to further develop the fi...ion and development., , ,When: Available for Inter...
(Date:11/24/2009)...rio, Nov. 24 Dow AgroSci...ssets of Hyland Seeds, a division of Thompsons Lim...Seeds will further expand Dow AgroSciences, curren...troduction of SmartStax(TM) in 2010 and Dow ...n corn in 2012. The transactional close is expecte...
(Date:11/24/2009)... employment grew by 29,000 jobs in October, and t...rowth during the U.S. recession. However, clinics ...lth systems are coming closer to having to actuall...ators. , (Vocus) November...ing in October despite the shedding of jobs in mos...
(Date:11/24/2009).... 24 NeurogesX, Inc. (Na... on developing and commercializing novel pain mana...onno, President and Chief Executive Officer, is sc...y Health Care Conference, to be held December 1-2,...w York. ,, Mr. DiTonno and Stephen Ghiglieri, ...
Breaking Biology Technology:Dow AgroSciences Canada Announces Agreement to Acquire Hyland Seeds 2Dow AgroSciences Canada Announces Agreement to Acquire Hyland Seeds 3The MedZilla Report for October 2009 - Health Care Employment Grows Again in October Even As Clinics, Specialty Centers Close 2The MedZilla Report for October 2009 - Health Care Employment Grows Again in October Even As Clinics, Specialty Centers Close 3The MedZilla Report for October 2009 - Health Care Employment Grows Again in October Even As Clinics, Specialty Centers Close 4NeurogesX to Present at Piper Jaffray Health Care Conference 2NeurogesX to Present at Piper Jaffray Health Care Conference 3
...rocessing Services selected BMC Software ,s MAIN...esponse time of its credit card and credit applica...ervices provides outsourced credit receivables man...Fiserv Credit Processing Services provides clients...nage credit decisions, account acquisition, accoun...
...many ways to share information. But most of us rel...oint. , ,We all use portals of various types. News...hat portals. Some of us use project management, da...all these are now available not only as stand alon...ns that are available 24/7. , ,The problem is tha...
...tion , a global supply chain technology solutions ...a-Pacific headquarters in Shanghai, China. With an...sixty employees by the end of 2004. The office is ...t development for the Far East. RedPrairie is the ...adquarters in China. , ,"Creating a strong presen...
Other Biology Technology:E-Mail Collaboration Problems 2E-Mail Collaboration Problems 3E-Mail Collaboration Problems 4
...53; Agarose Gel-Digesting Preparation contains a u... EPICENTRE for simple, quantitative recovery of in...ose gels following electrophoresis in TAE, TBE, MO...directly in the TAE, TBE, MOPS, and phosphate elec...
...heer in-house demand is causing shortages in your ...s antibody. This can cause unwanted distractions, ...for your hard work and endeavour! Bring us your id...nally. We work under ISO 9001 quality assurance in...
...assays for interferons are cytopathic effect inhib...ys. Sample types include; tissue culture supernat...ons. In these assays, one unit is defined as the ...reduce the cytopathic effect of viral infection by...
Mae II from Roche Applied Science
Biology Products: