Wondering about State of the Environment? Just Eavesdrop on Bees

Science Daily    Source: Cell Press        May 22,2014

Want a simple way to monitor wide swaths of the landscape without breaking a sweat? Listen in on the 'conversations' honeybees have with each other, researchers suggest. The scientists' analyses of honeybee waggle dances suggest that costly measures to set aside agricultural lands and let the wildflowers grow can be very beneficial to bees.

Researchers have devised a simple way to monitor wide swaths of the landscape without breaking a sweat: by listening in on the "conversations" honeybees have with each other. The scientists' analyses of honeybee waggle dances reported in the Cell Press journalCurrent Biology on May 22 suggest that costly measures to set aside agricultural lands and let the wildflowers grow can be very beneficial to bees.

"In the past two decades, the European Union has spent €41 billion on agri-environment schemes, which aim to improve the rural landscape health and are required for all EU-member states," says Margaret Couvillon of the Laboratory of Apiculture and Social Insects at the University of Sussex. "However, there is little evidence evaluating these schemes. Our work uses a novel source of data -- the honeybee, an organism that itself can benefit from a healthy rural landscape -- to evaluate not only the environment, but also the schemes used to manage that environment."

Couvillon and her colleagues, led by Francis Ratnieks, recorded and decoded the waggle dances of bees in three hives over a two-year period. Bees dance to tell their fellow bees where to find the good stuff: the best nectar and pollen. The angle of their dances conveys information about the direction of resources while the duration conveys distance. Researchers can measure those dance characteristics in a matter of minutes with a protractor and timer.

In all, the researchers "eavesdropped" on 5,484 dances to find that the best forage within the 94 km2 of mixed urban-rural landscape included in the study -- as far as bees and, by extension, other insect pollinators are concerned -- is a place called Castle Hill, which happened to be the only National Nature Reserve in the area. More broadly, High Level agri-environment schemes were the best places for bees.

The researchers were surprised to find that Organic Entry Level agri-environment schemes were the least frequented by bees. According to Couvillon, it may be that the regular mowing required initially to discourage certain plants from growing in those plots might leave few wildflowers for bees.

The study shows that honeybees can serve as bioindicators to monitor large land areas and provide information relevant to better environmental management, the researchers say. It also gives new meaning to the term "worker bee."

"Imagine the time, manpower, and cost to survey such an area on foot -- to monitor nectar sources for quality and quantity of production, to count the number of other flower-visiting insects to account for competition, and then to do this over and over for two foraging years," Couvillon says. "Instead, we have let the honeybees do the hard work of surveying the landscape and integrating all relevant costs and then providing, through their dance communication, this biologically relevant information about landscape quality."

Read at...
http://www.sciencedaily.com/releases/2014/05/140522123453.htm

Story Source:

The above story is based on materials provided by Cell PressNote: Materials may be edited for content and length.

Journal Reference:

  1. Margaret J. Couvillon, Roger Schürch, Francis L.W. Ratnieks. Dancing Bees Communicate a Foraging Preference for Rural Lands in High-Level Agri-Environment SchemesCurrent Biology, 2014; DOI: 10.1016/j.cub.2014.03.072

Scientists Decode Honeybee 'Waggle Dance'

 The Guardian   By Alison Benjamin   April 3, 2014

Unique form of communication allowed researchers to map the distance and location where bees foraged from month to month 

A honeybee who has found a good source of nectar or pollen performs a waggle dance to tell her nestmates where she has foraged. Here she repeatedly communicates that the profitable food location is at approximately 750m from the hive and about 270 degrees from the sun's azimuth

Honeybees fly much longer distances in the summer than in the spring and autumn to find good sources of food, a new study has found.

Researchers at Sussex University spent two years decoding the "waggle dance" of thousands of honeybees, a form of communication by which the bees tell their nestmates where to go to get the best source of food to bring back to the hive.

By measuring the angle of the dance in relation to the sun and the length of time the bee waggled its abdomen while moving in a figure of eight pattern, researchers have been able to map the distance and location where bees forage from month to month.

With a one second waggle equating to a foraging distance of 750 metres, the bees dance language revealed that the area they covered in search of food is approximately 22 times greater in the summer (July and August) than in spring (March) and six times greater in summer than in the autumn (October). In the summer the area they cover is 15.2km sq, compared to 0.8km in spring and 5.1km in the autumn.

Honeybees will not waste valuable time and energy travelling to find food if they don’t need to, so the researchers say the results, published in the journal PlOS One, show that the summer is the most challenging season for bees to collect the nectar and pollen from flowers.

“There is an abundance of flowers in the spring from crocuses and dandelions to blossoming fruit trees. And in the autumn there is an abundance of flowering ivy. But it is harder for them to locate good patches of flowers in the summer because agricultural intensification means there are fewer wildflowers in the countryside for bees,” said Frances Ratnieks, professor of apiculture at Sussex University, who supervised the study.

Honeybees face many challenges including increasing lack of forage because of modern farming practices.

The researcher say the results can be used to focus efforts to help bees better. “The bees are telling us where they are foraging so we can now understand how best to help them by planting more flowers for them in the summer,” said Ratnieks.

This video describes the research project Waggle dance distances as integrative indicators of seasonal foraging challenges carried out by Margaret Couvillon, Roger Schürch and Francis Ratnieks at the Laboratory of Apiculture & Social Insects (LASI) in the School of Life Sciences, University of Sussex

Honeybees may also have to forage further in the summer because they have more mouths to feed when the colony expands to 50,000 bees and there is more competition for food from other insects and pollinators including bumblebees.

The glass-fronted observation hives are located at the university campus surrounded by the South Downs countryside and a few kilometres from the city parks and gardens of nearby Brighton and Hove.

The waggle dance clearly show that the bees are heading to the downs in the summer and researchers are currently examining which flowers they are feeding there.

The honeybee dance language was first decoded by Austrian scientist Karl von Frisch who was awarded a Nobel prize in 1973 for the discovery.

Ratnieks said its work will benefit other pollinators, such as bumblebees.

“Mapping the waggle dance will allow us to help other species, because where honeybees find good food, we have already found a plethora of other pollinating insects feeding there,” said Ratnieks. “So we can improve forage for all these insects.”

The Sussex research comes as the the IUCN's latest "red list" of threatened species update warns that 24% of Europe’s 68 bumblebee species are threatened with extinction. According to the Status and Trends of European Pollinators, loss of habitat and wildflowers due to modern farming practices and urban development, plus changes in temperature from climate change, are the main threats to the species.

Read article (and comments) and view video at: http://www.theguardian.com/environment/2014/apr/03/honeybees-fly-further-in-summer-to-find-food-study-shows?commentpage=1
Video: https://www.youtube.com/watch?v=yELA7pvNUQI#t=115
Related articles: 
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0093495
http://www.sussex.ac.uk/newsandevents/?id=24883&intrefk=slideshow&intrefv=slide3

(FYI:  There were numerous comments to this article, such as:

"The waggle dance was first decoded by Austrian scientist Karl von Firsch who was awarded the Nobel prize in 1973 for the discovery."

The question was asked: "Why was it necessary for Sussex academics to spend two years studying the English waggle dance?" 

Response: "You ask why, but if you read the paper linked to in the article it clearly explains why. 
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0093495

Essentially because the waggle dance has been so well studied, it has been decoded. Therefore the waggle dance can be used to work out the foraging distances of the Honeybees.

The study says that most previous studies decoding the waggle dance have only been over a few weeks or months of the much longer year. This it says is partly down to the time consuming nature of decoding the waggle dance. However, advances have made it easier to decode the waggle dance. Therefore they set out to use this methodology to work out the Honeybee's foraging distances for the whole year.

The reason for this study is because of the decline of Honeybees. They wanted to know how far bees foraged at different times of the year and whether more flowers may help in an agricultural landscape, which often has large areas devoid of food (flowers) for foraging bees.

In other words it is part of the strategy for understanding and reversing the decline of Honeybees. The decline of Honeybees has a great cost, and if they decline even more, along with wild pollinators it might seriously effect agricultural production (almond production in California is already badly hit), and have major economic impacts.

So you ask how much this costs as if it is a waste of money, when the intention is to save the money being lost due to the decline in Honeybees."

Response: "Thankyou for providing the apparent reason for the work, which was to extend Frisch's work to the whole of the active season. This key piece of information was missing from the article.")