Dancing Bees Heather Mahaney September 26 th, 2002

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

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

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

Labeling

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

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.

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

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

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.

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

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

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

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

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

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

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

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

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

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.

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.

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

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.

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