The box is actually 2 obstacles in 1 and the instructions are:
4. Create a gap that is closed at one end. You can use a corner so that you only need to create one side. Sides must be solid as the horse must walk into a ‘box’. The ‘box’ must be at least 3m(10ft) long, no more than 1.5m (5ft) wide and must have solid sides at least 1m (3ft 3in) high. Send your horse into the gap, handler stays at entrance. Halt for a count of 3.
5. Handler backs horse out of 'box' by standing at opening of box and backing horse towards him, handler may move feet.
I actually thought this one would be easy. Ha, ha, silly me! I thought it would be easy because we have previously played around with a narrow gap that was effectively an open ended version of the box. Fat Pony has quite happily walked, trotted and backed through the open ended box, as well as halting in the middle of the gap. And we have been doing our stand and wait exercises almost every day for the last 2 weeks at least. And Fat Pony's party trick is to back towards me when I am standing behind him, quite often when I don't want him to, ha, ha.
So I stood with confidence at the entrance to the box and sent Fat Pony in. At first he didn't want to go in and tried to go round the sides. I made the communication clearer and he realised I wanted him to go in. So then he rushed in, quite obviously looking for the way out. Seeing where this was going, I gave him the cue for wait. That did get him to stop and think for a moment, but he was quite clearly feeling trapped and in the end his desire to get out of the tight spot won and he jumped over the end of the box. Not bad from a standstill! At least the jump confidence training has paid off, lol. The second time he turned himself around, quite a feat in a 1m wide space!, and came back out of the entrance.
I'm not sure exactly why he should feel claustrophobic about the box. He is reasonably good within the tight confines of a horse trailer and other narrow spaces. I think the fact that I am "driving" him from behind (as per the course instructions) has something to do with it. Also the fact that I've been building his confidence over jumps and teaching him to stay straight and go over when pointed at 1m wide objects will have contributed to him jumping out. I don't think that he's scared of the obstacles that make up the box. I think the most likely explanation is that the course is set up in an area where he is regularly bossed around by The New Girl and he is genuinely worried about being trapped (and then kicked). So the approach to teaching this one will probably be to: 1. break the task down and teach it to him in smaller pieces until he understands the pattern; and 2. try to build his confidence that he is not going to get trapped and kicked as long as I am doing the obstacle with him (New Girl may have to be banished from the area during training!).
It's a very nice challenge, a good reminder not to take his confidence with the other obstacles for granted!