Dancing Bees

1. Dancing Bees Heather Mahaney September 26th, 2002

2. Discovery • Karl von Frisch • Vienna • Nobel Prize 1973 • The Dance Language and Orientation of Bees • Experiments began 1923

3. Methods • Observation Hives • Large – 6 combs • Small – 2 combs • Shape – Flat • Combs visible • Temperature Regulation • Wedges

4. Labeling • Color Lacquer Dissolved in Alcohol • 5 different colors • 2 different spots on the thorax • Duration – several weeks • Method – mark bees while they are getting sugar water

5. Labeling

6. Artificial Feeding • Watch glass filled with sugar water • Colored paper under dish to resemble flower • Attract by putting drops of sugar water in the hive entrance. • Trail to artificial flower • Only want bees from one hive

7. Challenges • Spring Time • Natural food sources are good. • Hard to attract to artificial sources. • Late Summer • Natural food sources are scarce. • Hard to keep other bees away.

8. Nutrition • The hive needs both nectar and pollen to survive • Nectar – 120 kg • Pollen – 20 kg • Must have correct balance • Consume and Store

9. Food Sources • Foragers monitor food sources within a 62 sq mile radius of the hive • Choose the best food sources • Constantly changing needs and resources

10. Foragers • Each hive sends several thousand bees to collect food daily. • ¼ of total population • No Scouts • When a good source is found, other bees are recruited there to gather food.

11. Foraging • Each bee can find flowers over 3.7 miles away. • Travel at 5.5 mph • 400,000 body lengths = 372 human miles

12. Foraging • Covers a 62 sq mile distance around hive. • Most foraging within ½ mile • Large area = large variety of food sources • Best shortly after blooming

13. Feeding • Bee finds good food source • Fills honey stomach • Flies home • Finds recipients • Drops of honey water in mouth • Bees drink through probiscus • Dance

14. Dance - Measuring • von Frisch used a protractor and drew lines with on the glass to measure angles • Also used a rotating disk with gridlines 2cm apart placed parallel to the direction of the dance • Measured length of circuits with a stop watch • Motion picture

15. Dance – Process • Bee distributes food • Dances • Distrubutes more food • Dances again … • Done in highly populated area • Others follow with their antenna against her abdomen.

16. Dance - Types • Tail-Waggle – greater than 100 m • Transition: Round -Waggle – 25m to 100m • Round – Food source within 10m

17. Round Dance • Bee runs in a small circle • Runs over 6 adjacent cells • Reverses and returns

18. Tail - Waggle • Run in a straight line • Return in a semicircle • Run again • Return on the other side

19. Tail - Waggle • Direction indicates direction of source • Distance proportional to distance of source • Buzzing • Low sugar – little wagging, no buzzing

20. Surveillance • Colonies effectively survey their foraging range for new patches of flowers. • When sites are found, bees return to the hive and dance to recruit others. • Upon discovery, bees dispatch quickly to the new site before competitors can find it.

21. Food Sources • Colonies concentrate their resources on the riches food sources. • When food is scare, bees are less selective. • When food is plentiful, bees feed on only the best food sources.

22. Beeswax Combs • Used for rearing and food storage. • Initially build 20,000 cells • Up to 100,000 cells by the end of the summer • Create new combs when current combs are full and nectar is prolific

23. Pollen • Colonies only store small amounts of pollen. • 50kg of honey but only 1kg of pollen • Pollen contains protein, constantly consumed over the summer when plentiful.

24. Water • Colonies adjust their water intake due to environmental situations • Colony needs water to regulate hive temperature on hot days • Nurse bees need water to produce liquid food for larvae on cool days