Range management can help save prairie birds, according to recent Canadian research.
Good range management, says Brenda Dale of the Canadian Wildlife Service, provides what grassland birds need to survive. "Large blocks of native habitat in good to excellent range condition are best-case scenarios for grassland birds," she says, because they offer needed variation in cover height and thickness.
Management of riparian areas is also important because cottonwood forests along prairie rivers support larger bird populations and species diversity than communities in surrounding uplands. Andrew Hurly of the University of Lethbridge in Alberta and ecological consultant Elizabeth Saunders surveyed nine riparian sites: three ungrazed, three moderately grazed and three intensively grazed. Bird communities were assessed in both breeding seasons and fall migration periods.
"Bird breeding and diversity generally decreased from ungrazed to heavily grazed sites," Saunders says. Fluctuation in bird species is tied to grazing's effects on shrub cover, not directly to the presence of the cows. As shrub cover increases, so do riparian bird populations.
They also found that the diversity of insect species decreases as grazing pressure on riparian areas increases. And, the health of cottonwood forests decreased significantly under increasingly heavy grazing.
It's important, say Saunders and Hurly, that riparian areas are not subjected to high levels of grazing. Birds and vegetation can be a measure of a healthy riparian zone, which will support limited grazing year after year.
For more information contact Walter Willms, Lethbridge Research Centre, Lethbridge, Alberta at 403/317-2218 or e-mail [email protected]
A new way to protect consumers from harmful bacteria that may be found in meat has been discovered by scientists from the Center for Antimicrobial Research at California State Polytechnic University, Pomona.
The breakthrough involves applying a small amount of lactoferrin from cow's milk to the surface of meat during processing. Lactoferrin is a naturally occurring protein in mammalian milk that is credited with protecting infants from harmful bacteria while their immune systems are developing. By discovering how to activate the lactoferrin molecule, scientists were able to mimic its function on meat.
Laboratory tests showed the activated form of lactoferrin to be effective against more than 30 kinds of harmful bacteria, including E. coli O157:H7, Salmonella and Campylobacter. Lactoferrin does not change the taste, flavor, color or appearance of meat.
Researchers say the amount of activated lactoferrin required to protect a serving of meat is many times less than the amount of lactoferrin found in a single glass of milk. Lactoferrin currently is produced from whey, a byproduct in the manufacturing of cheese from cow's milk.
Activated lactoferrin can be applied easily to meat products at the processing plant as an added step to the meat industry's existing multiple-hurdle bacterial control process, the researchers say. Because lactoferrin remains on the meat's surface, the compound may provide lasting protection from bacterial exposure after processing.
For more information contact Narain Naidu, director of the Center for Antimicrobial Research, at 909/869-3788, or e-mail [email protected]