After right clicking a strider with a saddle, there is no way to get the saddle back again.
MC-177857
Can’t Take Saddles off of Striders
Resolved
Duplicate
1
With a pig, you can only get the saddle back by killing it and not simply removing it somehow. This is works the same with the Strider, but you would have to do it on land otherwise the saddle drops into the lava.
See MC-177569