Using a squirrel call can help you catch the squirrel easily in the field. It can help to both locate squirrels and sometimes even bring them into shooting range.
The call that I have the most experience with is the Primos Squirrel Buster, although all other calls I have tried seem to have similar tone and function. The majority of squirrel calls operate in the same way. The basic chatter call is done by holding the call around the mouth between your thumb and pointer finger, and shaking the call vigorously. The result is a high pitched chatter. The tone of the chatter can be matched to your target species of squirrel by muting the call to varying degrees by cupping your hand over the mouth. I find this call is almost as much fun as a noise maker than a squirrel call. It drives my dog crazy!
The calls can then be used to imitate a squirrel “bark” by holding the call as before, and slappling the bellows with your other hand.
Finally, the call can be blown into, imitating the a “squirrel in distress” squeal call.
As with any game call, it will not be effective if used to simply blast noise throughout the forest. Correct tone, and knowning when to call are key in using a call effectively. The most common mistake is probably over-calling. Most calls will come with some direction as to how to use the call effectively.
Once you have a pretty good feel for how to operate your call, you need to know when to call. I have had the best results while using the call as a locator. I will send out a chatter, and sometimes, of course not every time, one or more squirrels will respond. This will give me any idea of which direction to start hiking in. Once i feel i am near where the squirrel originally called from, I will give out a second call. This time if the squirrel responds, I will likely be able to locate it and get a shot off.
If used correctly, a squirrel call will definitely improve you hunting success.