Tucsonians of all ages went batty and piled into the dry Rillito riverbed for the third annual Bat Night.

There are 40,000 bats that live under the Campbell Avenue Bridge from April to September and fly out nightly to forage for food. Bat Night officials invited the Tucson community on Saturday to come together to watch the bats and mourn the loss of the riparian ecosystem of the Rillito riverbed.

People donned bat earrings, played with bat puppets and dressed children in Batman shirts in the spirit of the event.

From chihuahuas to Great Danes, even man’s best friend left the doghouse to watch bats fill the skies.

This year the Rillito River Project worked closely with the UA.

Visual communications graduate student Jessica Gerlach turned Bat Night into her thesis project.

Gerlach created banners, illustrations and cards each representing a species that no longer lives in the riverbed.

“”The species are being highlighted because the habitat for this species has been lost in this riverbed, so we are trying to reflect on the loss of those species,”” Gerlach said.

Gerlach began her research in February and worked through the summer to see the project to its fruition.

After creating the illustrations and cards, Gerlach worked to get volunteers who would be able to talk about each species and hand out the cards.

“”I’ve always been really interested in the connections between our environment and educating people,”” Gerlach said. “”I feel like visual communications is a field where educating can happen if you make dynamic kinds of events like this.””

Gerlach’s banners surround a giant sandbox and stage created by the UA College of Architecture.

Around 25 UA arts and architecture students were up at 6 a.m. filling sandbags to create the sandbox and stage for the event.

The idea of using the sandbags came from UA architecture alumna Jennifer Heinfeld, who was interested in creating an temporary structure.

“”We can create this great space, create these structures and then when the event is over, empty out the bags and it’s like nothing ever happened so it’s a great way of making something ephemeral,”” said Beth Weinstein, assistant architecture professor.

The sandbox was filled with children and costumed play leaders during the event.

“”I feel it’s really important that people notice the river, become aware of the river, become aware of the fact that the river used to have water year round. Because there is only water here part of the year, the animals and plants that are here are disappearing and that’s really our fault,”” Weinstein said. “”It’s important that people become aware of our impact, the fact that we’re here, we’re making all of these other living things disappear so we should maybe think twice about how we build and develop.””

Bats began trickling out from under the bridge around 6:30 p.m. though getting the crowd to stay quiet and keep control of their flashlights was a problem.

Noise and light frightens bats so it was important for the crowd to limit noise and avoid shining flashlights under the bridge.

Yar Petryszyn, retired UA senior curatorial museum specialist, served as a bat expert for the event.

“”It’s great to see so many people interested in bats,”” said Petryszyn, noting that bats used to have a bad reputation as being scary. “”With this many people showing up the whole image is changing.””

Alicia Norse’s first grade class at Senita Valley Elementary School spent a month learning about bats in preparation for the event.

Two UA students picked Bat Night over the UA football game.

“”I love local events in Tucson, they are definitely worth going to,”” said Libby Casavant, a hydrology junior.

Camille Adkins-Rieck, an international studies junior, said she would normally be at the game but this year she decided not to buy a ZonaZoo pass.

“”We were really surprised when we first drove up and saw so many people,”” Rieck said.

BAT FACTS

Bats are the only flying mammal, the flying squirrel does not count because it technically glides.

• There are about 1,000 species of bats worldwide, that’s about a fourth of all the species of mammals in the world.
• In the United States there are about 45 species of bats.
• In Arizona there are about 28 species of bats.
• The largest bat in the world is the flying fox and has a wingspan that is almost six feet long.
• The smallest bat in the world is the bumblebee bat and it weighs 2.5 grams.
• Under the Campbell Avenue Bridge is the twilight bat weighing at 3 to 4 grams with a wingspan of about 6 inches.
• A nickel weighs five grams so the twilight bat and the bumblebee weight less than a nickel.
• About 70 percent of bats are insect feeding, 25 percent are fruit and nectar and the other 5 percent go after other things like frogs and fish.

-Facts are from Bat Expert Yar Petryszyn