What's new
TerraForums Venus Flytrap, Nepenthes, Drosera and more talk

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

Sarracenia, actual trap mechanism

I've always assumed that prey slips and falls into Sarracenia. Recently I've watched a little closer. I have observed flies eating nectar while on the underside of a S. leucophylla lid. As they try to fly away they look like they get "sucked" into the trap.

Has anyone else observed this or know of a study done on this subject?
 
I've always assumed that prey slips and falls into Sarracenia. Recently I've watched a little closer. I have observed flies eating nectar while on the underside of a S. leucophylla lid. As they try to fly away they look like they get "sucked" into the trap.

Has anyone else observed this or know of a study done on this subject?

There is a theory that the beating of an insect wings creates an area of low pressure inside the funnel that keeps the prey trapped. I've never heard of it acting like a vacuum and sucking the insects in.
 
There is a theory that the beating of an insect wings creates an area of low pressure inside the funnel that keeps the prey trapped. I've never heard of it acting like a vacuum and sucking the insects in.

I've heard that as well but do not believe it for this reason. I have seen flies being caught, fall to the bottom of the pitcher and fly out. Note that there was prior prey in the pitcher but I do not believe enough to cancel out a funnel effect. As for Josh's notes, maybe gravity affects the fly as it loosens it's grip on the lid; then the fly tries to fly away negating the dropping effect. Just a crazy theory ???
 
I find pitchers that are full of tiny fruit flies that can't fly out. I can't remember, does Schnell talk about this in his book?

My observation is that lid size and shape play a really important role in trapping the fly. Something about taking off from an upside-down position and getting too near the convection zone area of the lip...

Maybe bending a lid back with twist ties or cutting it off entirely would make the pitcher catch less bugs.

There is a theory that the beating of an insect wings creates an area of low pressure inside the funnel that keeps the prey trapped. I've never heard of it acting like a vacuum and sucking the insects in.
 
i too have heard of the "vacuum phenomena" of beating wings. and coincidentally, tonight I heard a loud buzzing and located a x catesbaei that had a yellow jacket trying to fly out, unsuccessfully. it was a very lg. leaf, with what seemed like plenty of room for it to just fly out, but the hornet was like stuck in limbo about 2/3 of the way up.
 
i too have heard of the "vacuum phenomena" of beating wings. and coincidentally, tonight I heard a loud buzzing and located a x catesbaei that had a yellow jacket trying to fly out, unsuccessfully. it was a very lg. leaf, with what seemed like plenty of room for it to just fly out, but the hornet was like stuck in limbo about 2/3 of the way up.

I have heard wasp trying to fly out of my judith hindle, but i always look back into the pitcher and stare at it's unsussesful eyes. my cousin got scared cause she thought a bee was gonna try to sting herr.
 
Back
Top