The Urban Bee Project's Protocol For Data Collection
(Bee Monitoring)

All of our work in the wild and urban areas of northern California is based on what we call “Bee Frequency Counts.” These counts are used to assess bee-flower relationships – that is, to get a picture of which bees like what flowers when. By carefully observing flowers and the bees that visit them, we can begin to determine what bees and flowers are present during different times of the year, which bees visit which kinds of flowers, and how attractive different flower species are to bees.

Materials

Best Procedures For Monitoring

1.) Take a look outside and make sure it’s nice day! Sunny, warm days of 70°F or higher, with little to no wind are optimal for bees. Generally, bees are out and about between 10:30am and 3pm. However, it is fun (and important) to experiment with monitoring at different times of day. We may be surprised to find that some flowers offer nectar much earlier or later than the set time, coaxing the bees out of bed.

2.) Survey the garden for those patches of flowers that are in full bloom – these are the patches on which you will be monitoring. Sometimes, patches of flowers will not quite be in full flower, or may be starting to go out of season. These patches can also offer good information, and you will have to use your judgment to determine whether the patches are good enough to monitor.

3.) In order to assess the bee-attractiveness of a flower species, it is important to know what flower species you are monitoring! Hopefully, the flower patch will be labeled with the flower’s scientific name. If it has only a common name, you may be able to look it up in an ornamental plant guide such as Sunset Western Garden Book. If the patch is not labeled, your best bet is to pick a branch or two with flowers and leaves and bring it to a nursery for identification.

4.) Choose your first flower patch (1.5m X 1.5m or the equivalent in case of linear plantings) and begin by filling out the Bee Frequency Data Sheet (PDF format). You will need to include information about the weather, your monitoring site, the flower patch, and nearby flowering plants. You will need a Data Sheet for every flower patch you monitor.

5.) Then, without getting too close to the flowers (so as not to scare away the bees) begin your counts. Each count should take 3 minutes. You will need to check your watch often to make sure you are counting for the right amount of time. Be sure to count every bee that lands on the reproductive parts of the flower (usually the pollen or nectar center), distinguishing between honey bees, bumble bees, large bees, and small bees. You can write these down as you see them, but you must be careful to keep watching the flowers even as you write so as not to miss a bee. It may be easiest to make a little chart (see below), simply putting a mark under the appropriate category when you count a bee:

Finally, you must make sure to count each bee only once. It is not accurate to count the same bee landing on the same flower over and over again. With a little practice you will be able to keep track, in your peripheral vision, of all the bees you have already counted. If they fly outside the patch area and then return for more nectar, they can be counted again. Otherwise, you can leave their repeated visits out of your counts.

6.) Repeat these counts 4-5 times. It is best to step away from the flower patch for a few minutes between each repetition so that bees that were frightened off will return. During this time, you can continue filling out the “Counts” section of your Data Sheet. If possible, do each count on a different section of the same flower patch. If the flower patch is larger than 1.5m X 1.5m, you can divide the patch up into several sections for counting. If not, you can try to do counts from different angles (sides, back, and front). In the second case it is especially important to let the patch “rest” for a few minutes between each count.

7.) Take note of anything unusual or interesting you saw, such as descriptions of bee types, bee behaviors (like bees chasing each other around flowers), and different types of flower visitors (wasps, butterflies, flies). Enter these notes into your field journal, including a description of the weather, the time, what flowers you monitored, and anything else that caught your eye. You may even want to include sketches of the bees and flowers you monitored. Be creative!

8.) Sometimes flower patches of the same species can attract different frequencies of bees depending on whether they are surrounded by other attractive bee flowers or are isolated in a yard. It also may be that one particular patch may be producing more or less pollen and/or nectar treats for their bee visitors. In order to get an overall picture of a flower species’ attractiveness, you should try to locate other patches of this flower species in your area and repeat the frequency counts on at least three different patches. The overall attraction of the species can be categorized as follows: The plant is highly attractive (Common) if it averages more than 5 bees per 3 minutes; it is moderately attractive (Occasional) if it averages between 1 and less than 5 bees per 3 minutes; it has a low attraction if it averages between 0.5 and 1.0 bee every 3 minutes.

9.) Once averages are determined for bee frequency counts on a particular plant, and the visiting bees are categorized into groups, predictive information begins to emerge as to what relationships can be expected for a given plant. This information is very useful from an academic standpoint, as well as for planning residential bee gardens.