Japanese spiders?

Good day.
During my Japan visit I noticed the huge amount of spiders sitting in trees, even in fences, poles and so on. They had various colors on the main body, about 8-9 cm across including legs I assume. Took a picture if it would help.

They didnt do anything but felt a bit creepy. Are they native? Poisonous? Dangerous or just insect sweepers?

As far as I heard the most dangerous critters are habu snake and the giant hornet, and perhaps the japanese bear and mukade.

I am not worried just curious. I mean, I saw these even in central Kyoto so I bet they are not life threatening.

The Joro Spiders are all over Japan during autumn. We usually have two of them in our garden. I understand that they are completely harmless despite their scary look and size:
https://en.wikipedia.org/wiki/Nephila_clavata

I have seen these spiders many times when in Japan (and in Autumn).

I am quite an arachnophobe and they really did not scare me at all. Indeed, they seem to stay within the confines of their webs.

Well that is just the creepy thing, that they just sit there, somehow like an owl probing for its pray.

Anyway, so these are no dangerous at all?

Nope!

Probably because of the climate in summer, I am seeing an unusually large amount of spiders of various kinds this October here in Greater Tokyo. They seem to leave me alone as long as I leave them alone. Generally speaking, spiders we commonly see in Japan aren't poisonous and they eat the bad bugs, so I appreciate them.

Most of the scary wildlife in Japan is confined to the countryside. In Tokyo you may see nothing more exotic than a few unusual birds-I saw a parakeet on my last trip.

Read up on Dani mites/Tatami bugs. Chemical weapons are available from Konbini stores.

Redback spiders arrived in Japan from Australia. They are black with a red stripe on their bottoms. They are venomous. A bite can kill a child or an older person. When located in Japan, local authorities attempt to exterminate them. If you see one, kill it (carefully).

Huntsman spiders won't attack you unless you annoy them, and their bite is not poisonous. They are up to a foot across and jump on their prey from above.

Poisonous snakes are typically found in Okinawa. They would freeze to death in Japan in the winter.

The really cute deer at Nara will chase you and bite your bottom if they think you have crackers for them.

Japanese Giant Hornets, usually found in the countryside, are quite scary. They can fly faster than you can run and are aggressive. One sting won't kill you unless you are allergic, but lots of stings will. Google for advice on how to minimise risks if you are visiting anywhere rural in the summer or autumn.

The Mukade is a giant, aggressive centipede whose bite is about ten times as painful as a bee sting. They are largely nocturnal.

Bats are a protected species (and may have rabies). Do not disturb them.

Roaches are common in the summer but harmless. Bag all food.

The crows in Tokyo have large beaks and bad tempers: don't get too close or try to feed them. Tokyo's pet and feral cats make an effort to avoid them and so should you.

Aside from that, most of the wildlife is harmless, and if you are really lucky you might see a cat-girl.

Ahhh...Dani mites/Tatami bugs

I got eaten alive by these at a ryokan in Asakusa some years back. Very itchy!!!