I need to pick some brains here. I want to know if anyone has personally experienced this or knows if someone else has. If you have not experienced it and are not a professional or have not started multiple horses in the past, please don't offer advice. I don't want to be mean, I just don't want to waste anyone's time. Also, before anyone says anything: I have a professional trainer, I have a fabulous vet and farrier, and I myself have experience with green horses and a lot of miles in the saddle (FEI dressage rider plus jumping and western experience). I am only asking here because this was a bizarre incident and I want to know if others have ever dealt with something like it. I am also going to consult my actual trainer and figure out a new strategy. Okay. So now onto the actual issue.

I have a lovely three year old gelding who I'm training myself. He's my up and coming dressage horse. He's everything I could really want in a three year old: smart, sweet, talented, and generally sane. I've had him since he was a little under two. He knows how to stand tied, he lunges beautifully, he wears tack and side reins with no issue, he ground drives at walk (though it's a little wobbly), yields and flexes to pressure, reads body language, walks past scary objects, walks and trots over tarps (though it's been a while on that one), stops as soon as I say "whoa", responds to voice commands, pivots, backs, trots in hand, halts if he sees someone lying on the ground (usually - work in progress, we have it about 60-70% there, and I think that's good for a baby), etc. He's a dream on the ground. He has a really, really good foundation. I put his first ride on him in May. We only walked, but we didn't need any ground assistance, and we had no issues. I've been sitting on him periodically since he was two. Before anyone says anything about that part: I mean sitting on him once every month or two for less than five minutes at a time, and MAYBE flexing his head each way. Also a lot of laying over his back. Nothing that would put undue stress on his joints. He's very bonded to me, and he definitely likes me. He follows me around like a puppy, and is always happy when I go to get him from the pasture. He trusts me and will do just about anything for me.

Today we had a little bit of an incident. I was standing in one stirrup and leaning over him, and I eventually progressed to mounting and dismounting. This is something we've done a lot of before. It's not new to him, and he's usually fine. He typically startles a little when I get off, but nothing worse than pulling his head up or stepping sideways, and it tends to go away later in the session. Today we had probably a good half dozen successful mounts and dismounts. Then we have the final dismount/ejection. We accidentally shuffled a few steps away from the block when he got curious about something a couple feet away, and when he was standing still again, I decided to get off. Bad idea, apparently. I took my right foot out of the stirrup and started to shift my weight, and he stuck his head down between his knees and started broncing. I would have stuck it if I'd had my stirrups, but since I didn't have that luxury, I ended up sitting behind the saddle and kind of slid off. He accidentally stepped on my thigh as well, but I'm okay. As soon as he realized there was a person on the ground, he stopped everything he was doing and stood still. I am very glad I trained that response. He did not, however, want me to touch him. Normal for him when he's fired up. I'm fairly impressed with his impulse control at standing still when he clearly wanted to keep bucking. Now, I would have been more okay with baby shenanigans at any point other than the dismount, but I am NOT putting up with bucking when a rider is getting off. I put him back to work and made him run it out until he was feeling rather sorry for himself and was willing to respond to me again.

I do not think this was a pain issue. He's sound, didn't care about literally anything else I was doing up there, and besides all that, he's three and barely backed. I also don't think it's a rushing the horse issue. We've been doing exactly this for a solid year. I also don't think he had too much extra energy since I had lunged him beforehand. Probably not overwork either, since this was a standard day for him (excluding the part where he had to run like a Kentucky Derby winner after his poor life choices). He definitely didn't just spook either, because when he spooks he does the typical Arabian thing (he's half Arab, half warmblood) and teleports sideways. So what the heck happened? And, more importantly, how do I get it to never happen again? Bucking at mounting or dismounting is a hard "hell no" for me, and I'm not tolerating it.

My current thought involves filling a pair of jeans with sand and sewing it shut and just getting him used to that flopping around up there. Probably push it off him a few times. I'm also considering getting him an aquabag. I think unstable weight might help him. Maybe also tie some weird stuff to his saddle and let him sort that out for himself. I'm also planning to work him harder these next few days to try and get him in a better mental place. I'm wondering if he might be going through some kind of phase... Sounds weird, but he definitely has in the past. Last time it was a bolting on the lunge line and subsequently crashing through fences phase (don't worry, dealt with that one VERY quickly and it has not happened since!), so I guess this time it could be bucking at dismount. Anyone have any other ideas of what to do here?

I agree with Rainview here. A lot of young horses will tolerate new, stressful things to a point, until one day it is too much for them. This confuses many more inexperienced riders, who believe that the horse has suddenly become "naughty" when really the tension has just led to a breaking point. Luckily you seem to have a lot of horse experience and the patience to go slow with this baby. Do you have someone on the ground with you when you mount and dismount? I would have them stand by his head and make a big fuss over him the whole time you are getting on and getting off. Pats, praise, treats if that's your thing. Lots of distractions that you can slowly wean him off of as he settles down and gets a more positive association with the process.

I also like your idea with the sand filled pants, I've seen other people use those but haven't done that myself. I would extend that to doing some desensitization work in general and incorporate objects touching him, then going over him, and then going under him (like sacking out but less cowboy-ish). Nothing has to be flapping and scary, but I think it's a good way to get horses used to objects that aren't our vulnerable selves moving up down and all around them.

It sounds like you startled him. Baby horses get distracted very easily, and while he was splorin it's possible that he just completely forgot that you were on his back, so when you shifted he had a HOLY FUCK WHAT IS THAT moment. I've never had this happen specifically while dismounting, but I have had similar incidents where the baby was relaxed and looking at something else and then got startled when I did something.

You know, I think the "HOLY FUCK WHAT IS THAT" moment sounds like the most likely thing with this particular horse. I hadn't thought of that. He is a little ditzy sometimes. I would absolutely believe he forgot I was there. I've definitely seen him zone out for a little bit, get distracted, and then suddenly pop back in to reality. This incident really didn't strike me as pain, generalized tension, or a general training hole because this is the first time anything of this degree has happened in over a year.

The tension with getting off does exist, but it usually goes away by my third dismount in a session, if it even takes that long. I keep things extremely positive with him because he's young and a bit of a sensitive little flower. He gets scratches, he gets praise, he gets treats, and he usually (excluding yesterday) ends up nice and relaxed by the end. Usually he ends up resting his hind foot and yawning. It is absolutely something we need to work on more, though. New strategy for that in the works so I don't get launched again. My trainer and I are planning to tag team this issue before it becomes a big problem. I'm open to suggestions.

I seriously doubt it's ulcers as he has no symptoms and has had no recent training issues besides this, and he's one of the chillest young dressage horses I've ever seen. Plus, he has very few risk factors as he lives in a big pasture 24/7 with grass and a horse friend. If I see more issues or symptoms popping up, though, I'll absolutely have the vet out. It would be a big concern if he started showing ulcer symptoms because his character is so consistent. I'll keep that on my radar.

I agree with the HFWIT moment. Babies often forget what they learned the first few times until they've done it a million times and know just what to expect. Don't get discouraged- it sounds like you're doing great with him!

If you're able to, I would suggest ponying him with an older/experienced horse. I've found that for young colts it gives them so much confidence and desensitizes them to seeing you above their head. They can also see and hear all the sounds from the tack, which can sometimes be the cause of them startling. For my colts, it also gets them familiar with the verbal cues I use specifically when riding. The older horse is a reassuring presence, kind of an "if he's not freaking out then I shouldn't be either" thing.

My first instinct when reading this was also in line with some of the previous comments reguarding him being startled by realizing you were on his back. This has happened to me a lot with the babies I have worked with. Even when they have a great foundation and have done it all before there are times that they zone out and then realize that something is there even though it has been there the entire time.

I've worked with a good amount of colt/filly starters and it sounds like you're doing all of the basics pretty well. One thing I noticed from all of the starters I worked with was that they always flex the horse each way, and then keep them flexed on whatever side they're getting off on. This is so if the horse did try to take off, you can quickly put them in a one rein stop. I agree with the comments above, it was probably just a scared baby moment, but if you're working with a trainer, + how good of ground work it sounds like he has, I'm sure you'll be able to find a good fix to it!

Are you using a mounting block? Sorry if you said your were. Getting on and off a bunch pulls on the back. If you had done it a bunch, he could be a bit sore. Try and lessen the getting on and off, especially if he's doing good. Move slow when getting off. With the babies, I like to drop my stirrups and swing my feet 1 as a warning, and 2 for momentum. Up to their shoulders then back, jump of and push away, so if he were to pull anything, your not in the danger zone.

Maybe the saddle doesn't fit well? Maybe, if you bought him with some training, he had a bad experience with whips/spurs/crops, etc.? When he bucked you, he was probably scared you would hurt him. (I'm not saying you would-horses are like that if they've had bad experiences)