Cooperative Extension San Joaquin County
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Nominate a leader in sustainable farming

The Agricultural Sustainability Institute at UC Davis is calling for nominations for the 2013 Eric Bradford and Charlie Rominger Agricultural Sustainability Leadership Award.

The award recognizes and honors individuals who have exhibited the leadership, work ethic and integrity epitomized by the late Eric Bradford, a livestock geneticist who gave 50 years of service to UC Davis, and the late Charlie Rominger, a fifth-generation Yolo County farmer and land preservationist.

Nominations are welcome for UC Cooperative Extension advisors and specialists as well as UC Davis graduate students, faculty members, and in special cases, alumni, for their work toward agricultural sustainability.

Award recipients receive a cash prize and may be invited to give a lecture hosted by the institute.

Nominations are due by Jan. 2, 2013. To nominate a leader in agricultural sustainability visit the ASI website.

The Bradford-Rominger award recipient will be announced in spring 2013.

Learn more about the award from last year’s recipient.

Posted on Sunday, November 18, 2012 at 10:12 AM
  • Author: Eve Hightower
Tags: Sustainability (4)

About those honey bees...

Eric Mussen
Colony collapse disorder (CCD) has certainly increased public awareness about bees — but also public misinformation about bees in general.

CCD, the mysterious phenomenon characterized by adult bees abandoning the hive, leaving behind the queen bee, immature brood and stored food, surfaced in the winter of 2006. Scientists believe CCD is caused by multiple factors: diseases, viruses, pesticides, pests, malnutrition and stress.

Meanwhile, misinformation about bees continues to surface.  Posts on Facebook, Twitter, Pinterest and other social media often caption a syrphid fly as a bee or a syrphid fly as a bumble bee. Magazine and newspaper editors frequently misidentify a syrhpid fly (aka flower fly and hover fly) as a honey bee. Even the cover of the well-respected book, Bees of the World, by Christopher O’Toole and Anthony Raw shows a fly, not a bee. University of Illinois-based entomologist Alex Wild, who received his doctorate from UC Davis, mentioned the error in his Scientific American blog.

So, we asked noted honey bee authority Eric Mussen, UC Cooperative Extension apiculturist based in the UC Davis Department of Entomology: What should the general public know about honey bees? Can you share some basic information? A honey bee primer?

First of all, honey bees are not native to the United States. European colonists introduced them to what is now the United States in 1622. The site: the Jamestown colony in Virginia. Then in 1853, the honey bees were introduced to California. The site: San Jose.

“Honey bees,” Mussen says, “are commercial pollination workhorses, while native bees — mostly solitary — pollinate the native plants of field and forest. Around 250 commercial California beekeepers operate about 500,000 honey bee colonies, approximately one-fifth of the country’s supply. Over 72 percent of commercial crop pollination is conducted in California, and about one-third of our daily diet is dependent upon bee pollination. We also have about 6,000 small-scale or hobby beekeepers, who tend to keep one to five colonies.”

Mussen attributes CCD with “fomenting great media and public interest. It also sparked an increase in the number of small scale beekeepers.”

About 60,000 individuals, including the queen, thousands of worker bees (sterile females) and drones (male bees) comprise a colony in the late spring/summer.

“Up to a thousand drones are present during the mating season,” Mussen says, “but they get evicted at the end of the fall.”

The drones serve one purpose: to mate with a queen. And then they die. When a virgin queen is about 10 days old, she will mate with 12 to 20 drones on one or more mating flights. The queen returns to the hive and begins laying eggs, as many as 2,000 eggs a day.

“Bees are vegetarians and live on pollen and nectar obtained from flowers or extra-floral nectarines,” Mussen says. “A mix of pollens is required to meet honey bee nutritional needs.”

During the active season, a honey bee colony each day requires an acre-equivalent of blooms in order to meet its nutritional needs. Bees store both pollens and honey for winter food. The bees usually forage within five miles of the hive. Nutrition is crucial to a healthy hive.

“Malnutrition impairs the protective physiological systems — particularly the immune system and detoxification system — and leads to less productive and shorter-lived bees,” Mussen says.

The bottom line: “More research is required to find better ways to reduce populations of honey bee parasites, reduce levels of honey bee diseases, and develop beekeeping management practices that prevent excessive losses of honey bee colonies during the year.”

Honey bee on blanket flower, Gaillardia.  (Photo by Kathy Keatley Garvey)
Honey bee on blanket flower, Gaillardia. (Photo by Kathy Keatley Garvey)

Honey bee on blanket flower, Gaillardia. (Photo by Kathy Keatley Garvey)

This floral visitor, a syrphid fly, is often mistaken for a honey bee. (Photo by Kathy Keatley Garvey)
This floral visitor, a syrphid fly, is often mistaken for a honey bee. (Photo by Kathy Keatley Garvey)

This floral visitor, a syrphid fly, is often mistaken for a honey bee. (Photo by Kathy Keatley Garvey)

Posted on Wednesday, November 14, 2012 at 8:42 AM

UC Davis scientist to lead UN effort to study livestock’s environmental impact

Frank Mitloehner
In the aftermath of Hurricane Sandy, climate change and global greenhouse emissions are a hot topic these days. Dozens of UC Davis scientists study many facets of the causes and consequences of global warming.

One of them is Frank Mitloehner, UC Cooperative Extension specialist and professor in the Department of Animal Science at UC Davis. Mitloehner has studied the role of the livestock industry in contributing to greenhouse gas emissions. Mitloehner was recently selected to chair a United Nations committee to measure and assess the environmental impacts of the livestock industry.

As chair of the new Food and Agriculture Organization of the United Nations (FAO) committee, he will lead representatives of national governments, livestock industries, nonprofits, and the private sector in establishing science-based methods to quantify livestock’s carbon footprint, create a database of greenhouse gas emission factors for animal feed, and develop a methodology to measure other environmental pressures, such as water consumption and nutrient loss.

“By the end of three years, we’ll have a methodology that’s globally accepted, that anyone in the world can use to quantify the environmental impact of their livestock,” Mitloehner said.

The FAO estimates that meat consumption will increase 73 percent by 2050 and dairy consumption will grow 58 percent over current levels. Methods of raising livestock differ throughout the world, with American producers being among the world’s most efficient. For instance, it takes approximately 20 Indian cows to produce as much milk as one dairy cow in the United States.

Mitloehner’ s research has found that livestock account for 3.4 percent of greenhouse gas emissions in the United States. The transportation sector, on the other hand, contributes roughly 26 percent.

“Transportation choices continue to be the main contribution to climate change and not, as is often depicted, food choices,” Mitloehner says. “This new program is an effort to harmonize methodologies to benchmark the environmental impact of livestock.”

Among the founding members of the committee are the governments of France, Ireland, the Netherlands, and New Zealand, as well as the European Feed Manufacturers’ Federation, the European Vegetable Oils and Proteinmeal Industry, the International Dairy Federation, the International Meat Secretariat, the International Egg Commission, the International Poultry Council, the International Federation for Animal Health, and the World Wildlife Fund.


Posted on Wednesday, November 7, 2012 at 11:03 AM

Hedgerows enhance bird abundance and diversity on farms

California’s Central Valley is home to a rich diversity and solid abundance of birds. Many are year-round residents, while others are migrants that winter in our valley or travel to destinations further south. Currently more than 400 species of birds call the Central Valley their home; these include raptors, songbirds, ducks, geese, shorebirds, hummingbirds, and others. (Download a checklist of Central Valley birds here.)

All birds depend on habitat for food, shelter and nesting sites. With a decline in habitat in the Central Valley, primarily due to agricultural expansion, urbanization and water diversions, there has been a significant decrease in the numbers and types of birds. Many bird species are now endangered, threatened or listed as species of special concern. Approximately 36 percent of our state’s historical grasslands, 9 percent of the original wetlands, and 2 to 7 percent of the original riparian forests remain. The Central Valley alone has lost more than 90 percent of the riparian, oak woodland and shrub land habitats.

Despite this loss and fragmentation of habitat, many birds continue to use remnant or restored riparian and upland vegetation around farms. Crops such as rice and alfalfa also provide important habitat and foraging areas for birds. Interest is also surging in restoring lands to enhance habitat for birds, including planting hedgerows of California native shrubs and grasses along field edges.

In a recent study by UC Cooperative Extension and Audubon California in Yolo County, researchers determined that hedgerow plantings along field margins helped increase the abundance and species richness of birds on farms, both for winter migrants and year-round species. Their data analyses, examining farms with and without hedgerows, showed that the presence of hedgerows tripled bird abundance and doubled bird species richness in these linear habitat features, but did not increase the bird abundance in the adjacent crops. Of the 2,203 birds counted during the winter and spring of 2011-12, hedgerows drew 41 species of birds, as compared to 22 species in control areas (weedy, semi-managed field edges). In addition, more than three times as many birds used the hedgerows during wintertime, compared to the spring breeding season. This highlights the importance of this habitat for migrating and overwintering birds.

Rufous hummingbird.
Of significant interest was the finding that bird pest species were using crops regardless of field edge habitat. That is, crop fields with hedgerows showed the same numbers of bird pest species (such as blackbirds that can damage seed crops), compared to crop fields without hedgerows. The researchers observed a total of 1,642 birds, representing 30 species using the adjacent agriculture fields. The minimal species overlap indicated that a different bird community was using crop fields, regardless of the presence of hedgerows. The researchers also found that crops were more heavily used in the winter than during the breeding season.

Hedgerows provide a variety of ecosystem services in agricultural landscapes, such as attracting native bees to enhance pollination and natural enemies to control pests in adjacent crops. Birds also feed on insects and rodents, potentially helping with pest control in crops. The value of hedgerows on farms for enhanced biodiversity and ecosystem services will hopefully encourage more landowners to establish them on field edges for conservation purposes.

Yellow billed magpie.
For more information on establishing hedgerows on farms, download the free UC ANR publication Establishing Hedgerows on Farms in California. A more thorough discussion of the study results highlighted in this blog will be published in the upcoming December 2012 issue of the California Society of Ecological Restoration newsletter, Ecesis. A conservation innovation grant from the Natural Resource Conservation Service will help expand and continue this important research.

Posted on Wednesday, October 31, 2012 at 7:57 AM
Tags: Hedgerows (5), wildlife (24)

Zebra mussels and quagga mussels threaten California water systems

Zebra mussels. (Photo by Amy Benson / U.S. Geological Survey)
Some of California’s many introduced species — plants, animals, insects, and aquatic organisms — have marked impacts on ecological systems.

Invasive aquatic organisms can impact fish, shorebirds, marsh plants, and other wetland species, and alter functions of lakes, watersheds, floodplains, and coastal ecosystems.

Estuarine ecologist Ted Grosholz, a UC Davis professor and Cooperative Extension specialist in the Department of Environmental Science and Policy, is an expert on invasive species and addresses outreach education on zebra mussels and quagga mussels.

These two invasive, freshwater Eurasian mussels—zebra mussels and quagga mussels — could have a profound impact on California’s lakes and water distribution systems.

Clogging of pipe by mussels. (Photo from Mussel Prevention Program, San Luis Obispo Co., Calif.)
Both quarter-sized mussels showed up in California about six years ago. They attach themselves to water conveyance systems — pumps, pipes, dams, aqueducts, and fish hatcheries — and proliferate. According to Grosholz, “our drinking water and agricultural irrigation systems could be shut down quickly by these organisms.”

Los Angeles water districts are coping with the mussels, which are in Southern California watersheds, and reservoirs and canals of the Colorado River. The larval stage of the mussels disperses readily in water, so it gets moved around easily. There is tremendous concern about their potential spread into Lake Tahoe, and they have recently shut down a reservoir near San Jose. These mussels have cost the state tens of millions of dollars.

Zebra and quagga mussels pose a serious ecological threat in California. In the Great Lakes, where they became established 25 years ago, they have removed phytoplankton — a food source for juvenile fish — thereby impacting the food web. They have also concentrated the environmental contaminant botulism, resulting in massive kills of diving ducks and shorebirds.

Aquatic invasive species are moved long distances by ships — in ballast water, hulls and attached to ships’ surfaces. Within California they can be moved by recreational and fishing boats, trailers and other equipment.

Ted Grosholz, estuarine ecologist at UC Davis. (photo by John Stumbos / UC Davis)
“Once aquatic species are introduced, the cat is out of the bag — they spread easily, and they’re very difficult to control,” notes Grosholz.

Since the state doesn’t have the resources to adequately enforce zebra and quagga mussel control, areas such as Clear Lake and Fallen Leaf Lake are establishing local mandatory vehicle and boat inspection programs.

Grosholz works closely with resource agencies and other organizations to develop programs aimed at identifying and reducing the spread of invasive aquatic organisms. “It’s important to increase awareness of these species because they’re such a problem,” says Grosholz. “Their impact on ecosystems is big, and early control is very important.”

To read more about invasive aquatic species, including zebra and quagga mussels, see:

CA&ES Outlook magazine, pages 4–7

Quagga/Zebra Mussel Invasion, UC Cooperative Extension Coastal Resources

Quagga and Zebra Mussels, California Dept. of Fish and Game

Quagga and Zebra Mussel Prevention Program, San Luis Obispo County, California

Quagga and Zebra Mussel, Calif. Dept. of Boating and Waterways

Posted on Wednesday, October 24, 2012 at 11:17 AM

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