Work will help scientists determine where the rare birds spend winter
Wildlife biologists at the University of Arkansas have captured and documented the first northern saw-whet owl in Arkansas.
Between 1959 and 2010, only a dozen sightings of this rare bird – much smaller than screech, barred or great horned owls – had been recorded in the state prior to the adult female recently captured by Kimberly Smith, University Professor of biological sciences, and Mitchell Pruitt, an Honors College undergraduate student majoring in crop, soil, and environmental sciences.
Using mist-nets, a technique that includes a fine-gauge, black nylon net to ensnare birds, the researchers captured and banded the owl at the Ozark Natural Science Center near Huntsville in late November. Alyssa DeRubeis, a naturalist and teacher at the center, assisted Smith and Pruitt, who had previously tried the method at other locations in Northwest Arkansas, including Devil’s Den State Park.
The northern saw-whet, whose habitat is typically the northern United States and along various ranges of the Appalachian Mountains, is a small, secretive species that prefers low, brushy areas, especially cedar forests. They eat mice and spend their days silently perched at eye level in trees. Their main predators are other species of owls – barred and great horned owls.
During winter, northern saw-whets are usually silent and difficult to locate, so little is known about their winter distribution. However, recent successes at banding stations in Missouri and Alabama caused Smith and Pruitt to suspect the birds might also occur in Arkansas.
“An interesting thing about saw-whets is some of them migrate south every year, even when there’s plenty of food up north,” said Pruitt, who will use the experience and research for his honors thesis. “This year food must have been abundant because capture rates have been down across the country. But some birds have trickled through.”
The researchers attracted the bird by playing a recording of the northern saw-whet’s call. Once captured, they examined the bird and took measurements, showing a large female adult in its second year of life; it weighed 86 grams (3 ounces) and had a closed wing-chord of 142 millimeters (5.6 inches). Males and females are distinguished by a combination of weight and wing length.
Mature northern saw-whets can be distinguished from juveniles by flashing a black light on the underside of the wing. Like several other owl species, saw-whets have fluorescent pigments called porphyrins under their wings, and the patterns differ between juvenile and adult birds, Smith said.
The researchers banded the bird to track its migratory pattern, which will help biologists determine where the birds are wintering. After banding and photographing the bird, the researchers released it. The owl then perched for 10 minutes on a nearby branch, and the researchers took one more photograph before it flew away.
Two weeks after the initial capture, Smith and Pruitt captured another adult female at the Ozark Natural Science Center.
“The fact that we were able to capture two birds in the same place within two weeks of each other is really incredible, given that this owl has only been seen in Arkansas about a dozen times in the last 55 years,” Smith said. “Even more unbelievable is that we have had three owls respond to our tape recording at the Science Center, suggesting that this owl might be much more common in Arkansas than previously thought.”
The researchers will continue their late-night study through spring this year and will repeat netting next fall and winter.
Unless one is a master bird bander, trapping or possessing migratory birds is illegal in the United States, Canada and Mexico. Smith is a master bird bander, licensed by the federal government. He also has an Arkansas Game and Fish Commission permit, an Arkansas Natural Heritage permit and permits from both the National Park Service and Arkansas State Parks. Pruitt is training to become a sub-permit holder.
Kimberly Smith, University Professor, Department of Biological Sciences
J. William Fulbright College of Arts & Sciences
Mitchell Pruitt, undergraduate student
Matt McGowan, science and research communications officer
Kimberly Smith | newswise
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences