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EPA Accused of Muzzling Independant Advisors

By DINA CAPPIELLO

WASHINGTON (AP) - Journalist and scientific organizations accused the Environmental Protection Agency on Tuesday of attempting to muzzle its independent scientific advisers by directing them to funnel all outside requests for information through agency officials.

In a letter Tuesday, groups representing journalists and scientists urged the EPA to allow advisory board members to talk directly to news reporters, Congress and other outside groups without first asking for permission from EPA officials. An April memo from the EPA's chief of staff said that "unsolicited contacts" need to be "appropriately managed" and that committee members should refrain from directly responding to requests about committees' efforts to advise the agency.
The scientific advisory board's office had asked the EPA to clarify the communications policy for board members, who are government employees.
"The new policy only reinforces any perception that the agency prioritizes message control over the ability of scientists who advise the agency to share their expertise with the public," the groups wrote.
The EPA relies on independent advisory boards to weigh complex scientific information and to advise the agency on policy, such as setting new standards for air pollutants. Recently, Republicans in Congress have been critical of the scientific advisory board overseeing the review of the ground-level ozone standard, saying it failed to evaluate the consequences of recommending a tougher limit.
The chair of that panel, H. Christopher Frey, said in an interview with the Associated Press Tuesday in which he stressed he was offering his personal opinion, that he found the tone of the EPA memo to be unnecessary.
Frey, a distinguished university professor in North Carolina State University's environmental engineering department, said that many of the scientists that serve on the committees are national and internationally-renowned experts and [...]

Cornell Annual Short Course June 23-27, 2014

Introduction to Tilapia Nutrition

By Kevin Fitzsimmons
University of Arizona
One of the great advantages of tilapia for aquaculture is that they feed on a low trophic level.  The members of the genus Oreochromis are all omnivores, feeding on algae, aquatic plants, small invertebrates, detrital material and the associated bacterial films.  The individual species may have preferences between these materials and are more or less efficient depending on species and life stages in grazing on these foods.  They are all somewhat opportunistic and will utilize any and all of these feeds when they are available.  This provides an advantage to farmers because the fish can be reared in extensive situations that depend upon the natural productivity of a water body or in intensive systems that can be operated with lower cost feeds.
In extensive aquaculture, the fish will be able to grow by eating algae and detrital matter and the farmer can grow more fish in a given area because the fish are depending directly on the primary productivity of the body of water, primary consumers.  Fish which feed on a higher trophic level, eating larger invertebrates or small fish, are secondary consumers and a system can only support a fraction of the biomass of secondary consumers compared to primary consumers.
In intensive systems, tilapia have the advantage that they can be fed a prepared feed that includes a high percentage of plant proteins.  Carnivorous fish require fish meal or other animal proteins in their diets, which in general are more expensive than plant proteins.  Nutritional studies which substitute plant proteins supplemented with specific amino acid supplements may lower costs, but still not to the level that can be achieved with tilapia diets.
Complete diets are used in systems that cannot provide any [...]