I'm not sure but I would imagine so, I think that they are easy to pickle. You could at least pickle them, then pickle the next lot in a new jar and then mix them all together when they are done, in case you are worries about some being more pickled than others, IYSWIM.
Think you're right, Lazyline... The seeds were labelled gherkin, but we've certainly had some difficultly distinguishing them from the cucumbers which we are aiming to grow for salad.
Think we'll try doing them as you suggest and see how we get on. To be honest, the rest of the family eats them so fast, it's not going to matter if the pickling isn't perfect. Not much chance of them lasting for weeks!