Gossamer silk from balloon spiders
Ballooning is a term used for the mechanical kiting that many spiders, especially small species…use to disperse through the air. Many small spiders use gossamer or especially fine silk to lift themselves off a surface or use the silk as an anchor in mid air. The very fine silk used for ballooning has been called “gossamer” since 1325 and was not originally known to be produced by spiders; by extension, the same word is used metaphorically for any exceedingly fine thread or fabric. Biologists also apply the term “balloon silk” to the threads that mechanically lift and drag systems.
A spider or spiderling after hatching will climb as high as it can. The spider then stands on raised legs with its abdomen pointed upwards. This is known as “tiptoeing”. After that, it starts releasing several silk threads from its abdomen into the air, which automatically form a triangular shaped parachute. The spider can then let itself be carried away by updrafts of winds, where even the slightest of breeze will do. Most rides will end a few metres later, or a spider can be taken up into a jet stream, which depends on its mass, posture, the convection air current, drag of silk and parachute to float and travel high up into the upper atmosphere.
One of my favorite early summer signs. The prevailing westerlies always catch many gossamer threads along our eastern fenceline.