Owls are only connected to the New Age in the latter's embrace of the occult and superstition because this is where most "owl lore" originates.
Those beautiful wide-eyed birds (watch out, I'm a bird lover!) have a long history of association with the occult, mostly because of their appearance and the two tufts of feathers on their heads that resemble devil's horns (on some breeds). Because of their nocturnal habits and their shrill and piercing calls, they are associated with all things "spooky" and have thus found a place in the folklore of a variety of cultures both ancient and new.
For example, owls are used as a symbol of magic and witches are often associated with these birds. One superstition holds that witches can turn themselves into owls who then swoop down and suck the blood of babies. Owls were often thought to be messengers for sorcerer's and witches.
Rose Smith of Halloweenhowl lists the following superstitions about owls on her site:
* An owl hooting or screeching at night could result in the death of a newborn baby, will cause the child to have an unhappy life, or possibly that the baby would become a witch. If the owl was heard screeching during cold weather it signaled that a storm was coming.
* Owls apparently are the only creatures that can live with ghosts, so if an owl is found nesting in an abandoned house, the place must be haunted.
* Death is often associated with owls such as if: an owl perches on the roof of your house or hearing an owl hooting constantly nearby.
* If a traveler dreamed of an owl, then that meant he would be robbed or possibly shipwrecked.
* A silly owl superstition is that if you see an owl perched in a tree and you walk around and around that tree, the owl will follow you with it’s eyes, turning his head around until he wrings his own neck. (The reality is that an owl cannot turn his head completely around).
* Not all superstitions were bad. Owls were also believed to bring good fortune in some cultures. An Afghanistan legend states that it was the owl that presented humans with flint and iron so they could make fire. In exchange, man gave owls their feathers.
* The Aborigines of Australia believe that owls are the spirits of women and are therefore sacred, while in Brittany is was a good sign to see an owl on the way to the harvest as it meant that it would be a good yield that year.
* The owl is a symbol of guidance and help by the Inuit’s of Greenland, while the people of Indonesia saw them as wise beings using the owl’s different calls to determine whether to travel or not.
Your concern about your daughter's new necklace may or may not be warranted, depending on why she is wearing the jewelry. If she's wearing it as a kind of talisman or good luck charm, then she should be discouraged from doing so as this is superstition, which is considered to be a violation of the first commandment (Catechism No. 2111).
However, if she's a bird lover like me and just likes the look of birds, then there's nothing wrong with wearing the necklace.