Tag Archives: pollination

Ecosystem services

Colony Collapse Disorder: a loss of resilience?

4 Comments

In Science, Francis Ratnieks and Norman Carreck write about what has been learned about the collapse of bee populations in Clarity on Honey Bee Collapse? (2010 327 (5962): 152)

Over the past few years, the media have frequently reported deaths of honey bee (Apis mellifera L.) colonies in the United States, Europe, and Japan. Most reports express opinions but little hard science. A recent historical survey pointed out that extensive colony losses are not unusual and have occurred repeatedly over many centuries and locations. Concern for honey bees in the United States has been magnified by their vital role in agriculture. The California almond industry alone is worth $2 billion annually and relies on over 1 million honey bee hives for cross-pollination. So what is killing honey bee colonies worldwide, and what are the implications for agriculture?

In fall 2006 and spring 2007, many U.S. beekeepers encountered hives without adult bees but with abandoned food and brood. It was widely believed that these were symptoms of a new and highly virulent pathogen. In the absence of a known cause, the term “Colony Collapse Disorder” (CCD) was coined. What have we learned about this condition since then? Are the symptoms really novel?

…

The first annual report of the U.S. Colony Collapse Disorder Steering Committee, published in July 2009 (15), suggests that CCD is unlikely to be caused by a previously unknown pathogen. Rather, it may be caused by many agents in combination—the interaction between known pests and pathogens, poor weather conditions that diminish foraging, lack of forage (16), and management factors such as the use of pesticides and stress caused by long-distance transport of hives to nectar sources or pollination locations. The increasingly technical process of beekeeping itself merits further research as far as its impact on colony health. For example, although pollen substitutes are now widely used, little is known about the interactions between nutrition and disease susceptibility. Further research is also needed to develop effective ways of keeping colonies healthy through good hive management based on appropriate chemical, and other treatments such as “hygienic” bees that remove diseased brood and can be bred using conventional methods. In Europe, the COLOSS (COlony LOSS) network, consisting of 161 members from 40 countries worldwide, is coordinating research efforts and activities by scientists and the beekeeping industry to address these and other issues related to honey bee losses, including CCD (2).

In February 2009, the high pollination fee, combined with a temporary reduction in pollination demand due to drought and reduced almond prices, resulted in a surplus of hives in California available to pollinate almonds. But this leaves no room for complacency. Almond pollinating beekeepers had a poor summer in 2009 in the Dakotas and neighboring states, where hives spend the summer making honey, with heavy rains delaying and reducing the honey crop. This delayed chemical treatments for Varroa mites, and many colonies were probably in worse than usual condition going into winter back in California. It will be interesting to see what happens in February 2010 when the almonds bloom. On a longer time scale, there is a worrying downward trend in U.S. hives, from six million after World War II to 2.4 million today. Is the future of U.S. commercial beekeeping going to be based on pollinating a few high-value crops? If so, what will be the wider economic cost arising from crops that have modest yield increases from honey bee pollination? These crops cannot pay large pollination fees but have hitherto benefited from an abundance of honey bees providing free pollination.

Ecosystem services

Ecosystem service questions: Whose pollen? Whose pollinators?

1 Comment

As the world becomes more human dominated and people enclose an increasing number of ecological commons we can probably expect conflicts over ecosystem services to become more common. In California there is currently a new conflict over pollination.  From Associated Press: Tangerine growers tell beekeepers to buzz off.

Is it trespassing when bees do what bees do in California’s tangerine groves?

…

Mega-grower Paramount Citrus has already sent letters to beekeepers near the company’s Kern County clementine groves threatening legal action and promising to seek “compensation for any and all damages caused to its crops, as well as punitive damages” if seeds develop. Company officials did not return phone calls seeking comment.

The new regulations would affect Kern, Tulare, Fresno and Madera counties in the southern San Joaquin Valley, where many orange growers converted to easy-to-peel tangerines. The fruit’s California acreage was expanded from 24,000 in 2005 to 31,392 in 2008 to compete with imports from Spain and the Middle East.

Tangerines and other normally seedless mandarins do not need bees to move pollen from the male to female parts of the flower in the process known as pollination. But if bees cross-pollinate the crop with the pollen of other fruit, mandarins develop undesireable seeds.

Almond trees on the west side of the valley, on the other hand, need lots of bees to pollinate. For the February pollination season, almond growers hire beekeepers from around the country to bring tens of thousands of hives to California, home to 70 percent of the world’s supply.

As almond blossoms drop in late March, citrus growers say, beekeepers relocate hives to make orange blossom honey before heading to the Midwest for spring clover season.

Some growers, who by law must ban spraying for citrus mites and other pests when bees are present, say the bees are an increasing burden.

“We’ve coexisted with them, but we don’t need them,” said Joel Nelson, executive director of California Citrus Mutual, a trade association. “Now we’re trying to adapt to changing consumer demands, and we’re hamstrung.”

I wonder if this means that allergy sufferers will be able to sue people who plant pollen producing plants?

via Agricultural biodiversity weblog

Ecosystem services

How important are pollination ecosystem services?

2 Comments

Nature News reports on a paper by Aizen, Garibaldi, Cunningham & Klein in Current Biology (doi:10.1016/j.cub.2008.08.066) in an article Agriculture unaffected by pollinator declines

Bees and many other insects may be in decline almost everywhere — but agriculture that depends on pollinators has been surprisingly unaffected at the global scale.

That’s the conclusion of a study by Alexandra Klein at the University of California, Berkeley, and her colleagues. Using a data set of global crop production — maintained by the Food and Agriculture Organisation of the United Nations (FAO) — which spanned 1961 to 2006, they compared the yields of crops that require pollinators with those that don’t.

They found that crop yields for both crop types have gone up consistently, seeing average annual growth rates of about 1.5%. There was also no difference when the researchers split the data into crops from developing countries and crops from developed countries.

And when the researchers compared crops that are cultivated almost exclusively in tropical regions, they found no difference between the success of insect-pollinated crops — such as oil palm, cocoa and the Brazil nut — and those crops that need only the breeze to spread their pollen.

An interesting finding, but I expect that data collected at the national level is not able to detect current declines in pollination services.  In the news article Klein states that the data doesn’t show the extent to which farmers may have adapted to a decline, and that the world is becoming increasingly reliant on pollinator dependent crops.  They have grown from 8 % of developed world agricultural production in 1961 to about 15% in 2006.

This study also points out the gap between local level ecological understanding and regional to global assessment needs.

Ecosystem services

Agriculture unaffected by pollinator declines?

Leave a comment

Nature News reports Agriculture unaffected by pollinator declines. A new paper in Long-Term Global Trends in Crop Yield and Production Reveal No Current Pollination Shortage but Increasing Pollinator Dependency from Current Biology (doi:10.1016/j.cub.2008.08.066) shows that:

Bees and many other insects may be in decline almost everywhere — but agriculture that depends on pollinators has been surprisingly unaffected at the global scale.

That’s the conclusion of a study by Alexandra Klein at the University of California, Berkeley, and her colleagues. Using a data set of global crop production — maintained by the Food and Agriculture Organisation of the United Nations (FAO) — which spanned 1961 to 2006, they compared the yields of crops that require pollinators with those that don’t.

They found that crop yields for both crop types have gone up consistently, seeing average annual growth rates of about 1.5%. There was also no difference when the researchers split the data into crops from developing countries and crops from developed countries.

And when the researchers compared crops that are cultivated almost exclusively in tropical regions, they found no difference between the success of insect-pollinated crops — such as oil palm, cocoa and the Brazil nut — and those crops that need only the breeze to spread their pollen.