Record Details
Field | Value |
---|---|
Title | Mechanisms of orientation in the leaf-cutter bee Megachile rotundata (Fabricius) |
Names |
Osgood, Charles Edgar
(creator) Stephen, William P. (advisor) |
Date Issued | 1968-03-28 (iso8601) |
Note | Graduation date: 1968 |
Abstract | The leaf- cutter bee Megachile rotundata (Fabricius) is an important alfalfa pollinator in western North America. This study was designed to provide information on methods of orientation used by M. rotundata in order to make recommendations regarding the parameters within which adult nesting populations may be relocated. Preliminary studies suggest that this bee species may possess a sun compass although they depend predominantly on landmarks for orientation. Color discrimination experiments with bees conditioned to various colors (i.e., red, orange, yellow, green, blue and purple) showed that they could distinguish all colors except red from 22 shades of gray, black and white, Tests with yellow indicate that it was a much stronger stimulus for homing bees than other colors I) . tested. Bees appeared to be unable to distinguish red from black and therefore are thought to be color blind to red. Figure studies indicated that bees could discriminate between a variety of configurations including squares, circles, triangles, crosses, stars, I's and Y's. In these studies,bees were conditioned to a cross - shaped figure and tested for their ability to discriminate between it and triangles, squares and circles, all of three -inch maximum diameters. The data indicate that bees are quite able to make the distinction. Adult relocation studies indicated that population losses were high (50 per cent or more) when bees were moved from nesting sites possessing many landmarks (e. g., buildings, rows of trees) into alfalfa fields with few prominant landmarks; from field situations providing an abundance of foraging blossoms into fields with little bloom; and when strong winds prevailed. Conditions favoring minimum relocation population losses were moving bees with their original shelters into areas similar in landmark composition to original nesting sites; moving them in progressive steps of 20 -100 yards when relocating populations over short distances; color conditioning bees to shelters painted various colors before short distance moves; moving bees into areas with sufficient bloom to maintain themselves; and conducting moves when strong winds did not exist. General orientation was discussed with respect to flight range, landmark importance, nest entrance location and orientation inside the nest. With the advent of commercial nesting boards containing hundreds of similar nesting tunnels, bees experience major orientation difficulties. Recommendations are outlined in this study regarding methods to ameliorate proximate orientation problems using combinations of figures and colors applied to the surface of nesting boards. |
Genre | Thesis/Dissertation |
Topic | Bees |
Identifier | http://hdl.handle.net/1957/46873 |