A bald-faced hornet looking for a home in Tosa has a lot of options. According to UW-Extension, this species of yellowjacket typically builds its nest of a papery substance in the eaves of buildings, barns and overhangs or, when nowhere else is available, on tree limbs.
Add the ear of a troll to that list.
Since the City of Wauwatosa celebrated the opening of its newest park, Firefly Grove, in late May, the biggest draw has been its centerpiece statue, a towering troll known as Mama Rosa made from recycled wood by renowned Danish artist Thomas Dambo. Nearly from the start, the park's thousands of human visitors have been joined by an untold number of yellowjackets. Over the past three months their nest has steadily grown in the upper arc of Mama Rosa's right ear.
With Mama Rosa forever willing to pose for photographs as she clutches her bouquet of street lamps, the hornets nest likely has gone undetected by many of the visitors taking snapshots with the city's famous troll, though the insects' summer residence recently was highlighted on the Facebook group Dambo Troll Hunters, with more than 100,000 members.
"Quite the nest," one member said in an Aug. 17 post about Mama Rosa. A similar post on Aug. 21 suggested Rosa had an ear infection. One commenter compared the nest to a hearing aid. Others said they had noticed the nest earlier in the summer, and it has since continued to grow bigger.
No, not a hearing aid. Not an ear infection. And not a cause for public alarm — the nest is about 25 feet above the ground, out of human range — though City of Wauwatosa officials have been monitoring it.
"We typically don’t remove nests unless they are within 10 feet of a sidewalk, mailbox, driveway or some other area where people could encounter the hive," Alex Krutsch, Wauwatosa's parks and forestry superintendent, said in an update on the city's website that was first reported by the Milwaukee Journal Sentinel.
Such insects are a species of wasp that build their nests from chewed wood fiber mixed with saliva, according to an article on the UW-Extension website, which calls them "highly beneficial insects in the ecosystem."
"Their simple looking nest consists of a single layer comb resembling an umbrella shape and does not have any protective casing around it," it says. "In August, the wasp population peaks up and they actively scavenge foods rich in sweets and carbohydrates which naturally draw them to picnic spots, gardens, and outdoor cookout areas in search of juices and leftover foods in garbage cans, trash bags, and around overripe fruits."
Krutsch predicted that the nest will remain active until Tosa gets its first hard frost. After that, only the queen will remain, and whether her colony chooses to rebuild next year at Firefly Grove Park or finds a new neighborhood is anyone's guess.
What is certain is that troll fever is still running high at the corner of 116th Street and Gilbert Avenue. The park has begun hosting popular Friday evening gatherings with live music and food vendors, and even during midweek hours this summer, a regular stream of visitors has been waiting their turns to get photos taken with Mama Rosa.
On Aug. 25, Wendy Kapp was among them. It was her second visit to Firefly Grove Park. This time, she had brought her three grandchildren to play there for the afternoon — after first posing for a photo around Mama Rosa's feet.
"It's beautiful," Kapp told Tosa Forward News, speaking of the troll statue as well as the park in general. Her grandchildren ran to play, oblivious to the nest buzzing in Mama Rosa's ear.
The city's update about Mama Rosa also included a snapshot of (human) park usage during its first month. It estimated Firefly Grove Park was visited by more than 62,000 people from May 28 to June 30, most of those visitors coming from outside of Wauwatosa.
The city calculated the economic impact of those visits at $4 million based on typical tourism industry models intended to account for spending on dining, shopping, lodging, gas and other expenses connected with travel.
“These numbers show just how much Mama Rosa and Firefly Grove Park are drawing people to Wauwatosa,” said Beth Gleesing, the city's tourism specialist, said in the online update. “It’s exciting to see visitors from across the country exploring our city, supporting local businesses, and creating memorable experiences.”
