Watch out for iguanas... not because they are dangerous.. but because you could a dangerous for them... Tulum iguanas are quite small, and if you are not careful you might walk over one of them.
Also beware of fenced areas... most are there not only to protect monuments but also the little creatures.
When you're wearing sandals while you tool around the ruins in the Yucatan, use a little caution where you put your feet. While I was carefully framing a gorgeous shot of a sunning Iguana I felt a burning sensation on my right foot and it was crawling with fire ants! After that I saw them all over the place and was MUCH more careful. The pain fades pretty quickly and they didn't leave any marks, but it sure hurt while they were biting me!
Tulum isn't exactly like Cancun or Playa Del Carmen where you find a little shop every few steps where you can sit down to rest in the shade and buy a drink. The heat can be excruciating in Tulum; especially on a windless day, and you can sometimes find yourself a good 30-minute walk from a source of fresh water. This includes being at the ruins. I recommend you carry a litre bottle of water with you at all times to stay hydrated. I also suggest you have a bag of chips with you to replenish the salt your body loses through sweat. I did some fairly serious nerve damage in Mexico once by losing too much salt at the ruins of Chichen Itza. I got nerve twitches in one eyelid, in my arm, and chest--and they lasted on-and-off for 4 years. Backpackers should be extremely cautious when deciding to walk even several kilometers during mid-day.
Bonus Tip: At the far southern end of the ruins (to the right when facing the ocean) there is a tree grove and some small pavilions where you can rest in the shade.
If you live in cabañas on the beach you have to look out for all kinds of animals. Like bats coming inside your place, crayfish in the toiletbag, termittes in your bag, crabs on the floor and of course the mosquitoes. Bring a mosquitonet so you can sleep without worrying too much about who you might wake up with the next morning... ;)
A waiter in a restaurant told us about this "afternoon" party at a new hotel. It was a way to introduce us to the hotel. His friend worked at the hotel. Even though they don't call it a "time share" we knew that was probably what it would be. We enjoyed all we could drink and eat and full use of the beach with waiters for a day. It was enjoyable - but it was a lot harder sell than I thought it would be.
Something about dropping $40,000 while on vacation for a timeshare just doesn't sit well with me!
Contrary to what you may have heard about Mexico, I found Tulum to be a very safe and friendly place. The thing you have to watch out for here is the sun. I know I keep saying this, but I don't care how dark your skin is, use sunblock or you will end up in the emergency room packed in ice. And don't forget to do your feet. That's it.
This isn't exactly a Danger tip, it's more like a warning for those more "sensible" to some animals, such as snakes and iguanas.
I saw some snakes in the ruins and around them. They were very thin and didn't look dangerous, ... but i don't like snakes, so i kept my distance. :-)
And that place is full of iguanas. They are everywhere! Sometimes you don't even notice them since they have the same color as the ruin's stones, ... iguanas don't seem to be dangerous, they just look like they are quietly enjoying their place while loads of tourists get excited about them and shoot their cameras and try to feed them with flowers, ...
My valuables got stolen from inside the cabaña!!! :-( I was stupid enough to leave my bag in there for a short swim...
Don't leave anything valuable in there, and make sure your door locks well (ours didn't)! There also will be safety deposits (sometimes for free, sometimes they charge you) at the different hostels.
You might possibly lose your heart to all the cats at this resort. There were so many strays but the staff would feed them. We started taking a plate of food out after dinner to feed them. Some of them were so cute. This is my friend Julie feeding a few of them.
It's not a danger or a real warning, just an advisory about their mail service. My friend and I mailed postcards at the end of November that arrived at their destination in middle of January. And some were only going to the US! I think they walked them there. So if you're waiting for someone to say 'Got your postcard' you could be in for a long wait!
All along the road to Boca Paila and Punta Allen there are signs warning you to drive slow and look out for turtles and crabs crossing the road.
If you are a senior just watch very carefully your steps... If you are young just watch more carefully!!!
Loose rocks and stones...
And this cute criature that I found wandering around.