Does cervical mucus indicate ovulation or is there another reason it is produced each month?

It can: Cervial mucus is usually produced at midcycle. You may have an increase in amount around the time of ovulation. Some women have various levels of mucus production. If you want to know if you are ovulating at that time of increased production, you can use ovulation predictor kits that you can purchase over the counter.

Mucus = Estrogen: Cervical mucus is produced when the cervical glands are stimulated with estrogen. Normally the levels of estrogen rise up to the time of ovulation. After ovulation, the ovary produces Progesterone which causes the mucus to become pasty. So, the absence of thin slimy mucus means that either you are not making estrogen or you have ovulated. Ovulation is confirmed only after slimy mucus becomes pasty.