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The Endangered Delhi-Sand Loving Fly

The Battle Against Time to Save this Species

The Desert Habitat Fragment of the Delhi Sand Dunes in Colton California which is protected. Photo taken by Karem Villanueva.

The Inland Empire in Southern California is made up of a combination of various different habitats, with a range of over 230 species. Of these species, one is the Delhi Sands flower-loving fly.

Like the name states, it loves feeding on flowers as it is a pollinating fly, similar to bees and butterflies, but it hovers over them like hummingbirds. The interesting fact is that it was the first fly to be declared endangered by the U.S. Fish and Wildlife Service in 1993.

The fly inhabits the Delhi Sand Dunes in between the San Gabriel and San Bernardino Mountains. The Dunes have formed over time during the fall season when the wind is high, the Santa Ana winds push fine sand over and through the Cajon Pass to settle in the valley.

When first formed, the dunes covered over 50 square miles, but now only about 2% of this land is left. Of this, only about 100 acres are protected and not to be used for development. The most continuous piece of land is located from Ontario to Loma Linda, with the longest continuous area being in Colton.

This species is losing its habitat due to the increase in housing and industrial buildings. Within the past couple of years, construction has seemed to increase throughout the whole area. These new buildings take up lots of space, which takes away the habitat for numerous species. With this, only 2-3% of the habitat is left undeveloped.

The fly itself has been blamed for halting development projects in the Inland Empire, such as construction on roads. Civil Engineer Tiffany Luong who works for the city says that an important project taking place specifically in Rialto was pushed back due to the potential harm it could cause the species.

The project which had to do with fixing road conditions on Riverside Ave. in Rialto was halted due to the danger it posed to the ecosystem with the heavy machinery and fumes that would potentially be released, harming species in the surrounding area.

The good news is that this species receives protection under the Endangered Species Act, which aims to conserve plants and species at risk of extinction. It has reduced the danger that these species face by protecting the land where they reside.

The fly currently stays on private land, however, it is in constant threat of development. The U.S. Fish and Wildlife Service is in a long effort to protect the remaining land by having negotiations with local governments. If their plans go through, areas of land would be protected and not be used for development, but instead, be used to build an establishment for a captive breeding program to help increase the numbers.

Michael Viramontes, a land steward for the Rivers & Lands Conservancy, states that if we want this fly to stay around for longer, we must help maintain this habitat with more than just fencing off and protecting land. Much of this land is contaminated by dumped trash.

Viramontes created the Delhi Sands Flower-Loving Fly Education and Outreach Program, which goes around to schools to inform students about this fly and what we can do to protect it. Efforts include trash removal and habitat restoration, all with a goal to maintain the Delhi Sand Dunes for as long as species like the Delhi Sands flower-loving fly exist.

1 comment

1 Comment

Ximena Zepeda
Ximena Zepeda
Jan 31, 2023

It's kind of funny to think that a fly can have this effect on industry and construction here in Rialto. Nice article, all species should have a chance of thriving.

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