Is it permissible to combine stray camels with owned camels and pay Zakat on them, knowing that the stray camels have been in my possession for a full year?

It is not permissible to pick up a lost camel, because it does not need anyone to pick it up, as it is able to drink water and eat trees until its owner finds it. Zakat is not obligatory on it, due to the incompleteness of its ownership.