Usually when pups are born they snip all the dew claws off because they are not needed. They become a problem at some point if they are left on. They can still be removed at any age but the sooner you have it done the better and the cheaper it will be. Just get an estimate of cost from your vet and shop around for the best price. Let the vet know the pups were abandoned strays and you are trying to keep your cost down.
I noticed the dew claws right away in the one photo you posted and that is why I wrote something about it. They stick out like sore thumbs.
They are very obvious. If they aren't chipped we'll get them removed. And I'll tell the vet about them being strays to save on the cost so I can buy more dog food. lol