Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Habitat loss, not poison, better explains grassland bird decline

24.06.2014

Contrary to recent well-publicized research, habitat loss, not insecticide use, continues to be the best explanation for the declines in grassland bird populations in the U.S. since the 1980s, according to a new study by ecologists.

Last year, a pair of researchers linked the drop in the populations of grassland bird species, such as the upland sandpiper and the Henslow's sparrow, to insecticide use, rather than to a rapid decline of grasslands, a more commonly accepted theory. However, after re-examining the data, Penn State and U.S. Department of Agriculture researchers now believe that the loss of habitat continues to be the best explanation, said Jason M. Hill, a postdoctoral research associate in ecosystem science and management, Penn State.

"Many people think of grassland loss as something that happened long ago in North America, but the amount of grassland lost since the 1980s is absolutely staggering, whereas the insecticide use greatly declined prior to the 1990s," said Hill.

The researchers cited earlier studies that documented a loss of approximately 97,000 square kilometers -- an area larger than the stats of Indiana -- of grasslands in the U.S. between 1982 and 1997 primarily due to the expansion and intensification of agricultural practices.

The researchers were surprised that the other researchers excluded lands from the Conservation Reserve Program lands in their analysis. The CRP pays farmers to remove environmentally sensitive lands, especially grasslands, from agricultural production. Because grassland bird species tend to do better in states with larger areas set aside in the conservation land program, excluding the conservation land program data may have skewed their results, said Hill.

"We reanalyzed their data in a more statistically-appropriate way, including CRP acreage, and found 1.3 to 21 times more support that habitat loss was more strongly connected to grassland bird declines than insecticide use," said Hill. "Grassland bird trends were positively associated with the acreages of CRP lands and some types of pastures."

Erroneously emphasizing insecticides as the principle cause of grassland bird declines may inadvertently divert attention and funding away from land conservation programs such as CRP, according to the researchers.

"Conservation Reserve Program contracts are not being renewed," said J. Franklin Egan, research ecologist, USDA-Agricultural Research Service, who worked with Hill. "My biggest concern is that we get distracted and lose focus on preserving the remaining grasslands."

Grasslands, especially in agricultural landscapes, also provide tremendous benefits to humans through erosion reduction and water filtration as well as offering habitat to numerous grassland-obligate species from black-footed ferrets to Dakota skippers.

The loss of grasslands is a global problem, according to the researchers, who report their findings in the journal PLOS One.

"Grasslands and grassland-obligate species are declining not just across North America, but across the globe," said Hill.

Grassland bird species use the living and dead vegetation in grasslands to build nests and for use as cover.

"Grasslands are easily converted to farmland for row crops, such as corn and soybeans," said Egan, "Grassland species, with few exceptions, cannot survive on these intensive agricultural lands."

The researchers examined population data of grassland species in the 48 contiguous United States from the U.S. Geological Survey North American Breeding Bird Survey. In addition to information provided by the researchers on the study of insecticides and grassland birds, they also used data from the U.S. Department of Agriculture and the National Resources Conservation Services. Hill and Egan also worked with Glenn E. Stauffer, a post-doctoral scholar in forest resources, and Duane R. Diefenbach, adjunct professor of wildlife ecology, both of Penn State.

Matt Swayne | Eurek Alert!
Further information:
http://www.psu.edu

Further reports about: CRP Conservation explains grassland habitat humans insecticide insecticides poison species

More articles from Ecology, The Environment and Conservation:

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Understanding animal social networks can aid wildlife conservation
23.06.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Study shines light on brain cells that coordinate movement

26.06.2017 | Life Sciences

Smooth propagation of spin waves using gold

26.06.2017 | Physics and Astronomy

Switchable DNA mini-machines store information

26.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>