a family group of mature boar, sows and piglets is quite noticeable.
rooting, nesting, wandering about with squiggly piglets etc all have strong sign or direct observation
i would be aware it (or they)may be around but not very worried, they will avoid you if at all possible (or steal your lunch) and are only dangerous if they see you as a threat, if so back off politely telling them you will go that way so they can continue doing piggy things
a few apples and a night in a tree with a night sight is a viable option if they do seem to be a problem