Spring Collecting and Identifying Bumble Bees

Lesson Plan Number 4

http://bumbleboosters.unl.edu

                                                                           

Overview: Many factors influence the distribution and abundance of living organisms. They include the following: the availability of resources such as food, shelter and water, the presence of predators, diseases and parasites, and the climate. In scientific studies of populations, it is impossible for a scientist to collect all of the organisms of interest; therefore, scientists collect samples of populations. To reduce the risk of drawing conclusions from an atypical sample, they collect several samples and average their results. Scientists also collect samples from across the region of interest to be sure that their sample represents the true population.

Project: Students will collect bumble bees in the field, record data, pin and label specimens, answer conclusion questions, and send specimens to research leaders for verification.

Vocabulary:sample, distribution, curate, hypothesis, synthesis

Educational Goals:

  1. To advance students' understanding of the process of scientific data collection.
  2. To improve students' ability to work in research teams
  3. To increase students' ability to recognize bumble bee species
  4. To increase students' ability to recognize floral species
  5. To develop students' ability to curate a reference collection.
  6. To develop students' ability to synthesize from their observations and to generate hypotheses about the distribution of bumble bees in their area.

Scientific Goals:

  1. To collect and record information about the distribution and abundance of bumble bee species.
  2. To gain a better understanding of the floral preferences of each species.
  3. To write a research publication on the distribution and abundance of Nebraska bumble bee species and their preferred forage plants.

Materials Needed: Kill jars, ethyl acetate, aerial collecting net, 10X hand-lens, larval forceps, insect pins, pinning block, observation block, pen, field record book, and Bumble Boosters: A Guide to Identifying Nebraska Bumble Bee Species.

Introduction: The distribution and abundance of Nebraska bumble bee species is not known. Twenty different species have been reported in the state, but several species have not been collected since the early 1900's. Bumble bees are valuable pollinating insects. By collecting and recording data from around the state, the current distribution and abundance of bumble bees and their preferred forage plants will be established. Information gathered on preferred forage plants will guide land managers and homeowners who seek to conserve bumble bees by providing preferred forage plants.

The Lesson:

  1. Introduce students to background information prior to collecting bumble bees. The Bumble Boosters Web-site, instructional video, and books in the resource kit will be helpful. Information about the importance of pollinators and their impact on our environment can also be found in the instructional video and in the readings included in the resource kit. Students should begin by learning to distinguish bumble bees from other insects. The Bumble Boosters: Guide to Identifying Nebraska Bumble Bee Species provides information on how to identify bumble bee species. Introduce students to pinned specimens before they begin to collect. Students curious about the known distribution and abundance of species in their area can find information on the Bumble Boosters Web site (http://bumbleboosters.unl.edu).
  2. Discuss the importance of accurately recording scientific data. Students should prepare a lab notebook and record all data in the notebook. Determine how data will be collected, recorded, and analyzed before beginning any scientific experiment. The attached data sheet is a recommended model, but students should be encouraged to be creative in adding other variables that they think are important.
  3. Demonstrate collecting methods, or show the portion of the Bumble Boosters videotape that demonstrates collecting techniques
  4. Form teams of students for collecting bumble bees. There are three roles for students: collectors, equipment carriers, and recorders. One recorder and equipment carrier can support several collectors.
  5. Travel to a suitable collection site, usually where potential nesting habitat is found or near floral resources. In summer, bumble bees can frequently be found on sweet clover, purple vetch, white clover, penstemon, and red clover. In the fall thistles, Joe Pye weed, sunflowers, and monarda are highly attractive. Bumble bees can be found on many other plant species. The information you gather on plant species visited by bumble bees is an important component of the research data that will result from implementing this lesson.
  6. Collect specimens by capturing them in a kill jar or by collecting them in a net and transferring them to a kill jar. Jars with wide mouths and screw on lids are recommended.
  7. Record information about the collection site. Include information about the state, county, and location (quarter section, section, township and range coordinates are best, but text descriptions such as "3 miles South of Ord" are acceptable). Plat maps can be obtained from the Nebraska Department of Roads, the Nebraska Game and Parks Commission, and the County Engineer's office. Also include the date (19 May 2000), collector's name, and the floral resource where the bee was collected (if collected on a flower).
  8. After 20 minutes, specimens will be overcome by the ethyl acetate and can be removed from the kill jar. Do not leave specimens in the kill jar for over 30 minutes, or condensation may wet the bees' hair making them difficult to identify. Give each specimen an identification number and record specimen data on the collection data sheet provided with this lesson.
  9. Take specimens back to the classroom for identification. Specimens should be pinned as soon as possible after collection, because they will become brittle within a day. Bumble bees should be pinned perpendicular through the thorax between the wing bases just to the right of center. For illustrations on how to pin specimens, see page nine of Bumble Boosters: A Guide to Identifying Nebraska Bumble Bee Species.
  10. Follow procedures for identifying specimens found in Bumble Boosters: A Guide to Identifying Nebraska Bumble Bee Species or use the Bumble Boosters Web site: http://bumbleboosters.unl.edu . In most cases a hand-held lens will work for identifying specimens. However, some characters will be easier to see with a dissecting microscope. When examining specimens, mount them on one of the observation blocks provided in the resource kit.
  11. Record species and gender information for the identified bee.

  12. Make labels for each specimen. Labels can be hand-written with ink or printed with an ink jet or laser printer. Labels should be printed on stiff acid-free paper. Information for the labels will come from the student's lab notebook. There should be 2 or 3 labels for each specimen. The diagram below shows the information that should appear on each of the three labels.
  13. Label 1 (Collection Information)Label 2 (Floral Resource)
    NE: Lancaster Co.
    UNL East Campus
    25 August 2000
    Coll: J. Doe
    Medicago sativa

    Label 3 (Species)
    Bombus griseocollis
    The 2 label method simply merges label 2 and 3 together into one label.

  14. 13. Place specimens in shipping boxes. Shipping boxes should be placed inside a larger cardboard box and surrounded by Styrofoam peanuts, bubble wrap or other impact absorbing material. For confirmation of your identifications, include a data sheet for each specimen as shown on page 62-63 of Bumble Boosters: A Guide to Identifying Nebraska Bumble Bee Species. Specimens will be returned with comments on any species students did not identify correctly. To facilitate associating identification data sheets with specimens, number the specimen identification data sheets. Specimens should be given the same number as the corresponding data sheet. Duplicate numbering can be accomplished by adding a numbered label to the specimen. Alternately, students can draw a numbered grid on the Styrofoam base of their shipping box and place their specimens in numbered grids that correspond to the number on the specimen identification data sheets. Send specimens to:
  15. Bumble Boosters
    Entomology Department
    202 Plant Industry Building
    University of Nebraska-Lincoln
    Lincoln, NE 68583-0816

Conclusion: After establishing a collection, consider recording information on a classroom billboard or poster. Data points indicating where bumble bees have been collected can be recorded on a town or county map. Mapping collections will allow students to discuss bumble bee distribution and speculate about where they would expect to collect each species. Students can analyze their findings by preparing a graph showing the percentage of all bees collected for each species. They can make similar graphs for each collection trip to observe the changes in species abundance throughout the year. Summarize your data, and prepare a list of plant species visited by each species. Conclude this lesson by analyzing the data and associating species with the various habitats you sampled.

  1. According to the information gathered from the collections, which species emerge first in the spring?
  2. What is the most abundant species collected in your area? Does the sampling technique clearly indicate the most abundant species in your area?
  3. The presence of males indicates that nest populations are at a peak. Based on collection records, when does it appear that each species population reaches its peak?
  4. Is there a relationship between the type and abundance of floral resources and the number of bees collected in an area? What is this relationship and what does it really tell us?
  5. Does the time of day or the temperature affect the number of bumble bees collected? If so, describe the optimum time of day and temperature for finding foraging bumble bees.
  6. What combination of factors makes a "hot spot" for collecting bumble bees?
  7. Is there a more accurate sampling method for determining the distribution and abundance of bumble bee species?

References:
Bumble Boosters Web site (2000) http//:bumbleboosters.unl.edu

Golick, D. A., Ellis, M. D. (2000) Bumble Boosters: A Guide to the Identification of Nebraska Bumble Bee Species. University of Nebraska Press. EC 00-1564-S

Thanks to students from Kearney High School for contributing ideas about using a map and colored pins to analyze collection data. Thanks to the Lincoln Public Science Focus High School students for the idea of drawing numbered grids on Styrofoam to associate specimens with specimen identification data sheets.