Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Satellite Data Shows that Kirtland’s Warblers Prefer Forests After Fire

08.12.2011
Kirtland’s warblers are an endangered species of lightweight little birds with bright yellow-bellies that summer in North America and winter in the Bahamas.

But be it their winter or their summer home, a new study using data from NASA-built Landsat satellites shows that these warblers like to live in young forests and often forests that have been on fire.


The Kirtland's Warbler spends its summers in North America and its winters in the Bahamas. Credit: Dave Currie

The U.S. Fish and Wildlife Service listed Kirtland’s warblers as endangered in 1967 after a startling decline of over 50 percent in less than ten years. The little birds prefer to nest on the ground amidst large areas of relatively young jack pine trees, and these trees need fire to reproduce. When fires were dramatically suppressed in the 1960s across northern Michigan, Wisconsin and southern Ontario, the warbler’s habitat became scarce.

After an intensive recovery program that focused both on combating invasive cowbirds and managing controlled forest burns, and thus creating warbler-friendly jack pine habitat, the Kirtland’s warbler made an impressive comeback. By 1995 their numbers had tripled.

But those extensive efforts only occurred at the Kirtland’s summer home, so a team of researchers reviewed the conditions of many a warbler’s winter home – the Bahamian island of Eleuthera. They did this by painstakingly putting together Landsat data to create cloud-free images of the isle’s forest cover.

Tropical islands typically have cloud cover, so the team compiled many Landsat images with scenes where the clouds were in different places into one image of clear forest, said Eileen Helmer. She’s a member of the Landsat Science Team for the U. S. Geological Survey (USGS) and works for the U.S. Department of Agriculture Forest Service International Institute of Tropical Forestry.

The researchers did this not just once, but ten times, obtaining a record that spans a 30-year time period. According to Helmer, this allows them to tell how long it had been since the forest was last disturbed by fire, crops or grazing.

What the scientists discovered was that, like in their summer homes, Kirtland’s warblers are found in young forests. On Eleuthera, these forests only occur after a disturbance of some sort – like fire, clearing for agriculture, or grazing. And grazing turns out to be a disturbance the warbler can live with just fine. Old forest whose underbrush has been munched on by goats provides the most suitable habitat for warblers, said Helmer.

The results, published in this month's issue of Biotropica, suggest that goat grazing stunts the forest regrowth, so that the tree height doesn’t exceed the height beyond which important fruit-bearing forage tree species are shaded out by taller woody species. Helmer said that understanding how and where the warbler's winter habitat occurs will help conservation efforts in the Bahamas.

Helmer said that a unique feature of warbler’s winter habitat is that the age of this forest correlates very strongly with its height. By tracking the age of the forest after a disturbance, she and her team determined forest height at different times. Helmer said they used image time-series data from Landsat and the Advance Land Imager (ALI) sensor aboard the Earth-Observing 1 (EO-1) satellite to essentially ‘stack’ many images over time. This project is the first time that forest height profiles have been successfully mapped by satellite imagery at a medium resolution that shows a broad area but still resolves human impacts on the land. As in the warbler case, understanding how a forest is put together in three dimensions is important for ecological studies. Helmer adds that this tool may be applied elsewhere around the world due to Landsat’s global coverage and policy of free access to data. Helmer will discuss mapping forest height at the American Geophysical Union conference in San Francisco on Friday, Dec. 9.

The Landsat Program is a series of Earth observing satellite missions jointly managed by NASA and the U.S. Geological Survey. Landsat satellites have been consistently gathering data about our planet since 1972. They continue to improve and expand this unparalleled record of Earth's changing landscapes for the benefit of all.

For more information on Landsat, visit:
http://www.nasa.gov/landsat
http://landsat.usgs.gov/ Aries Keck
NASA's Goddard Space Flight Center
301-814-8858
Aries.C.Keck@NASA.gov
Rachel Headley
United Stated Geological Survey, EROS
Cell 605-360-3613
rheadley@usgs.gov

Aries Keck | EurekAlert!
Further information:
http://www.nasa.gov
http://www.nasa.gov/topics/earth/features/warblers.html

Further reports about: Bahamas FIRE Geological Geological Survey Landsat Landsat satellites Warblers pine tree satellites

More articles from Ecology, The Environment and Conservation:

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht World Water Day 2017: It doesn’t Always Have to Be Drinking Water – Using Wastewater as a Resource
17.03.2017 | ISOE - Institut für sozial-ökologische Forschung

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: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>