Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A changing landscape may have dire implications for birds

02.08.2004


In their desire to get close to nature by building lakeside cottages and homes in the woods, Americans may very well be hastening the decline of many native bird species that breed in forest habitats.



The development boom in the nation’s rural areas is putting increasing pressure on forest ecosystems, and the resulting decline in native vegetation and the increase in human activity - ranging from all-terrain vehicle use to predatory pets roaming the woods - is putting more and more native birds at risk, according to research presented Wednesday, Aug. 4, at the annual meeting of the Ecological Society of America in Portland, Ore.

The research, conducted by a team of scientists from the University of Wisconsin-Madison and the U.S. Forest Service, details broad patterns of birds’ response to housing growth and land cover change in the lower 48 United States.


The bottom line, according to UW-Madison researchers Anna Pidgeon and Chris Lepczyk, is that as rural forested landscapes are developed and parsed by roads and openings for new houses, many native bird species are at risk as deep forest breeding habitat is perforated.

Using data from the Breeding Bird Survey, a broad-based effort to monitor bird populations across North America, the researchers looked at changes in the abundance of species. Comparing that data to U.S. census data and the National Landcover Dataset, a satellite survey of land cover in the U.S., the Wisconsin and Forest Service team was able to sketch a broad picture of human pressures on native forest bird species.

"We have found in the Midwestern United States that as land cover becomes more human dominated, the number of species declines," says Lepczyk, who led a team that examined the roles of land cover and housing density on 137 species of birds, native and exotic. Of those, 37 species were affected negatively by humans, while 13 species had positive relationships and 23 species exhibited a mix of adverse effects and benefits from human shaping of the landscape.

"This mirrors nationwide results previously reported by Audubon," says Pidgeon.

Now, Pidgeon has expanded the study to begin to examine how the pressures of housing growth and land cover change have altered bird populations during the past 30 years across the 48 contiguous United States. "We are seeing geographic clusters within the U.S. where some species populations are increasing, which we suspect is due to increases in both generalist and exotic species," says Pidgeon.

While human population has grown significantly across the continental United States since the 1970s, Lepczyk says the number of houses sprouting up in previously undeveloped areas is likely having a greater impact than the raw number of humans inhabiting the landscape.

"Houses, we think, may represent a better indicator of impact (on native bird species) than human population," Lepczyk explains.

The study results portray an increase in exotic bird and generalist species, such as European starlings, pigeons, crows and jays, as a consequence of increased housing density on the rural landscape.

What clearly puts some native forest species at risk is the outright loss of wooded habitats as roads and lawns replace native vegetation, says Pidgeon. Not only does such development shrink available breeding habitat, but it also opens corridors for bird predators such as raccoons and skunks. Lawns also provide foraging areas for brown-headed cowbirds, parasitic birds that lay eggs in other birds’ nests.

"Roads provide access and increased edges that nest predators including jays and crows use," Pidgeon says, "and we know from the work of others that an increase in predation accompanies an increase in housing density" as the domesticated animals that accompany humans, cats and dogs in particular, exact a heavy toll on native forest bird species.

What’s more, human activities, such as the growing use of all-terrain vehicles and the replacement of native vegetation with exotic and ornamental plants, reduces cover and food resources for native birds.

Native species like house wrens, robins and catbirds can benefit from human changes to the landscape, but species like the scarlet tanager and some warblers depend on large, contiguous tracts of forest to successfully reproduce.

Humans, according to Pidgeon and Lepczyk, can benefit some birds by establishing feeding stations, sources of water and nesting boxes. But the increased density of housing, especially in northern deciduous forests, is having a net negative impact.

"Whole species, like the Cerulean Warbler, could be in jeopardy if we don’t preserve enough large tracts of mature deciduous forest. The $64,000-question is how much is enough?" says Pidgeon

Chris Lepczyk | EurekAlert!
Further information:
http://www.wisc.edu

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

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: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Structured light and nanomaterials open new ways to tailor light at the nanoscale

23.04.2018 | Physics and Astronomy

On the shape of the 'petal' for the dissipation curve

23.04.2018 | Physics and Astronomy

Clean and Efficient – Fraunhofer ISE Presents Hydrogen Technologies at the HANNOVER MESSE 2018

23.04.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>