How Tarantulas Hunt

[zeeman]

I expect this may vary by T type - fossorial, arboreal, or terrestrial - but hoping you guys / gals can enlighten me. I would check my book but I lent it to my father in preparation for his first T.

Originally I had thought Tarantulas use a combination of vibrations on their webbing and sight to hunt. I've read some threads on here where people state their eyesight isn't that good, which surprised me. Knowing that, and in cases where T's either don't web much, or haven't webbed, how are they finding their food? I'd think this may be more important for the webber that hasn't webbed yet, as if they don't have their main means of hunting, they may struggle to find prey in their enclosure (especially pre-kill) as its outside their skillset.

 

[Jadennn]

From my personal experience, and still consider myself to be a newbie, my different fossorial or terrestrial or arboreal species all eat differently and to me their eye sight does seem to be very minimal as some of my guys don’t react to much movement much above their face. I once dropped in a dubia with my curly hair who didn’t immediately catch it but felt the immediate vibration on the webbing mat she’s laid and I came back a day later to find her still crouch over the dubia not yet finding it till I gave it a tap for her

So I think mostly what I see is even with my not heavy webbing guys they all feel and sense the movement of things

 

[jaw6053]

Not sure if this was the same video I found on this forum a couple months ago or not but this will give you an idea of how sensitive each hair on your T is. This is how they can grab prey you drop in before it even hits the ground. I searched and searched the forum and could not locate the exact video link I was looking for so if you find it let me know.

 

[MBArachnids]

I have some 1st hand experience with something that surprised me a few years ago. My T. Vagans sits on top of her hide. (Driftwood piece that's hollowed out) The one branch extends away from the main body of wood and has a drop off to the sub of about 4-6cm.

I wanted to lure my T to the sub to get a good feeding video so I proceeded to drip a few water drops past her onto the sub expecting her to climb down to investigate. Instead what happened without a shadow of a doubt is she attacked the droplet BEFORE it would hit the sub 6cm below her. I did this a few times (4-5) with the same result. I could be crazy and you could disagree with me but I saw with my own eyes my T. Vagans sensing the movement in the air close to her.

This was an amazing experience for me and one I wish I could capture. Since then I have seen numerous videos of people tong feeding where pokies would lunge at the feeder when it hasn't even touched anything in the enclosure, just wiggling close to the T.

I would love to see a study of how sensitive a T's senses are in their immediate surrounding. (Ground and air around them)

 

[viper69]

I expect this may vary by T type - fossorial, arboreal, or terrestrial - but hoping you guys / gals can enlighten me. I would check my book but I lent it to my father in preparation for his first T.

Originally I had thought Tarantulas use a combination of vibrations on their webbing and sight to hunt. I've read some threads on here where people state their eyesight isn't that good, which surprised me. Knowing that, and in cases where T's either don't web much, or haven't webbed, how are they finding their food? I'd think this may be more important for the webber that hasn't webbed yet, as if they don't have their main means of hunting, they may struggle to find prey in their enclosure (especially pre-kill) as its outside their skillset.

Their sight is horrible- it’s a scientific fact. If you google and read scientific sources you will see this from experts vs general run of the mill forum statements like my own above.

Now if Ts had the vision of a jumping spider that would be a different story!!!

There’s a reason they have so many sensitive setae; it’s not because their vision is good!

 

[spideyspinneret78]

Their eyesight is very limited...they mostly just see light/dark and movement. However, they're extremely sensitive to vibrations. That's how they find their prey...by using their sense of touch. Their limited vision helps them orient themselves towards a prey item, but their many setae are exquisitely sensitive. It's always so incredible to watch them stalk and grab their prey, knowing that they're mainly using vibrations.

 

[MBArachnids]

I have some 1st hand experience with something that surprised me a few years ago. My T. Vagans sits on top of her hide. (Driftwood piece that's hollowed out) The one branch extends away from the main body of wood and has a drop off to the sub of about 4-6cm.

I wanted to lure my T to the sub to get a good feeding video so I proceeded to drip a few water drops past her onto the sub expecting her to climb down to investigate. Instead what happened without a shadow of a doubt is she attacked the droplet BEFORE it would hit the sub 6cm below her. I did this a few times (4-5) with the same result. I could be crazy and you could disagree with me but I saw with my own eyes my T. Vagans sensing the movement in the air close to her.

This was an amazing experience for me and one I wish I could capture. Since then I have seen numerous videos of people tong feeding where pokies would lunge at the feeder when it hasn't even touched anything in the enclosure, just wiggling close to the T.

I would love to see a study of how sensitive a T's senses are in their immediate surrounding. (Ground and air around them)

Just so there is no confusion, my T did not see the droplet it felt / sensed it I would assume. Also it never struck the droplet as she was fairly late with the strikes each time. (Late as in missed it but still reacted before said droplet would hit the sub)

I will try and re-create this when she emerges from her burrow after molting as I find it very interesting.

 

[Ah Lee]

I have both seen my T's attack prey that has burrowed under the water dish, and crawling a few cm above them. I suppose this means they can detect both ground-based and airborne vibrations, and they seem to be deadly accurate with them.

 

[DaveM]

I agree with @MBArachnids, and have seen Ts grab flying moths from the air, and grabbing dropped feeder insects before they hit the ground.

Also, in addition to the many very sensitive setae, it's worth considering the 'slit sensillae' organs, which are mechanoreceptors built into the exoskeleton, useful in sensing ground vibrations.
If you consider a T with eight legs splayed out in all directions, it can get a finely-tuned sense of the direction from which prey approaches by the differing strength/amplitude of the vibrations between legs (i.e. closest leg feels it strongest), and in the order in which the legs receive each vibration (i.e. closest leg feels it first). That covers the direction-finding.
Now for ranging:
Vibrations in the ground (e.g. from an insect walking) produce both longitudinal (amplitude parallel to the soil surface) and transverse waves (amplitude perpendicular to the soil surface). The longitudinal waves travel predictably much faster. Comparing the time difference between the arrival of longitudinal and transverse waves (in each of eight legs) gives the spider very accurate ranging. See lightning and count the seconds until you hear thunder; then you know how far away the lightning struck -- it works because light waves travel much faster than sound waves, and the difference in arrival time has a predictable relation to distance.
Eyesight hardly matters to them, doesn't work in the dark, and their vision is no good anyway. They still can sense their surroundings extremely well.

 

[Whiplash Girlchild]

They are very tactile creatures, mostly using movement. It is almost against physics, such ancient creatures. The webs they use are connected directly to their predation.

However, does anybody know if they use a lot of pheromonal communication?

 

[zeeman]

Thanks everyone for the replies, from first to the last.

Based on all of the above responses, feeding is based on movement. How then do slings find pre-killed prey?

 

[DaveM]

Thanks everyone for the replies, from first to the last.

Based on all of the above responses, feeding is based on movement. How then do slings find pre-killed prey?

You keep the sling in a small container, so it's bound to discover the pre-killed prey. For once, our artificial habitats resemble nature: small container, like burrow; pre-killed meal, like mother spider's leftovers!