# Alkali Fly (*cirrula hians*)

The alkali fly (Cirrula hians) is a remarkable shore fly species famous for its ability to thrive in extremely harsh hypersaline and highly alkaline environments, such as Mono Lake in California. Unaffected by the intense chemical conditions that would kill most other animals, these tiny flies occur in massive, dark ribbons along the shoreline, numbering in the millions. They play a critical ecological role as a primary food source for hundreds of thousands of migratory birds that nest or rest in these unique saline lake ecosystems. Historically, they were also a highly prized food source (Kutsavi) for the local Kuzadika'a Native American people, who harvested the pupae.

- **Category:** [Insects](https://www.snappit.app/explore/categories/insect)
- **Rarity:** Common
- **Danger:** 1/5 · Very low
- **Snaps:** 1
- **Habitat:** Found on the margins of highly saline, alkaline lakes and mineral springs, particularly where tufa towers and benthic algae are present.

![Alkali Fly](https://inaturalist-open-data.s3.amazonaws.com/photos/272229496/medium.jpg)

Photo: Adam J. Searcy, CC BY 4.0 · [iNaturalist](https://www.inaturalist.org/photos/272229496)

## Appearance

Alkali flies are small, robust flies measuring about 4 to 7 millimeters in length, with a dark, metallic bronze-brown to greenish-black coloration. They have large, reddish-brown compound eyes and short, stubby antennae. Their wings are clear or slightly dusky and are folded flat over their backs when at rest. A key defining feature is their dense covering of fine, water-repellent hairs, which gives them a silvery, shimmering appearance when submerged underwater inside their self-created air bubbles.

## Taxonomy

- **Kingdom:** Animalia
- **Phylum:** Arthropoda
- **Class:** Insecta
- **Order:** Diptera
- **Family:** Ephydridae
- **Genus:** Cirrula

## Interesting facts

- An alkali fly's hairy body is so hydrophobic that it requires physical effort for the fly to force itself underwater against the buoyant force of its protective air bubble.
- Mark Twain once wrote about the alkali flies of Mono Lake, marveling at how they could be held underwater and emerge completely dry.
- The Kutzadika'a people, a band of Northern Paiute, traditionally harvested the protein-rich pupae of these flies as a vital seasonal food source called kutsavi.

## Special abilities

- **Underwater Air Bubble:** They utilize dense, hydrophobic hairs to trap a protective bubble of atmospheric air around their bodies, allowing them to crawl underwater to feed and lay eggs.
- **Salt Tolerance:** Possess highly specialized carbonate-excreting organs that allow them to process and survive extreme concentrations of salt and alkali.
- **Submerged Grazing:** Specialized clawed feet allow adults to cling securely to underwater rocks and tufa structures to graze on benthic algae despite their natural buoyancy.

## Measurements & details

- **Length:** 0 cm
- **Wingspan:** 0-1 cm
- **Weight:** 0.000002-0.000005 kg
- **Lifespan:** 0 years
- **Speed:** 8 km/h
- **Clutch Size:** 50-150
- **Incubation:** 1-3 days

## Diet & Feeding

Adults and larvae feed primarily on benthic microscopic algae and cyanobacteria that coat underwater rocks.

- **Primary Foods:** Benthic diatoms, Blue-green algae, Cyanobacteria, Microscopic organic detritus
- **Foraging Method:** Grazing Dietchangeswithage

## Ecological connections

- **Eaten by:** [California Gull](https://www.snappit.app/explore/california-gull) (*Larus californicus*) — Gulls feast on adult flies and pupae along the lake shorelines.
- **Eaten by:** [Wilson's Phalarope](https://www.snappit.app/explore/wilsons-phalarope) (*Phalaropus tricolor*) — These migratory shorebirds consume massive quantities of alkali flies to fuel their long migration.
- **Eaten by:** [Eared Grebe](https://www.snappit.app/explore/eared-grebe) (*Podiceps nigricollis*) — Eared grebes dive to feed on alkali fly larvae and pupae.

## Safety

**Danger:** 1/5 · Very low

No special safety notes yet.

## Frequently Asked Questions

### How to identify Alkali Fly?

Look for six legs, antennae, three body sections and the shape of the wings. Beetles have hardened front wings; flies have just one working pair. Tiny insects may need a close view before their group is clear. Insect Identifier: upload a photo and compare the visible details.

### How long is Alkali Fly?

0 cm

### What is Alkali Fly's wingspan?

0-1 cm

### How much does Alkali Fly weigh?

0.000002-0.000005 kg

### How long does Alkali Fly live?

0 years

### How fast can Alkali Fly move?

8 km/h

### What does Alkali Fly eat?

Adults and larvae feed primarily on benthic microscopic algae and cyanobacteria that coat underwater rocks.

### Where is Alkali Fly usually found?

Found on the margins of highly saline, alkaline lakes and mineral springs, particularly where tufa towers and benthic algae are present.

## Where to spot

- [Mono Lake Tufa State Natural Reserve](https://www.snappit.app/guides/places/mono-lake-tufa-state-natural-reserve) — California, US · Nature Reserve

## More Insects

- [Common Eastern Bumble Bee](https://www.snappit.app/explore/common-eastern-bumble-bee) (*Bombus impatiens*)
- [Spotted Lanternfly](https://www.snappit.app/explore/spotted-lanternfly) (*Lycorma delicatula*)
- [Brown-belted Bumble Bee](https://www.snappit.app/explore/brown-belted-bumble-bee) (*Bombus griseocollis*)
- [Eastern Carpenter Bee](https://www.snappit.app/explore/eastern-carpenter-bee) (*Xylocopa virginica*)

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Source: [Alkali Fly: Characteristics, Facts & Places to See — Snappit](https://www.snappit.app/explore/alkali-fly)