Jordanella floridae

Flagfish

A Florida freshwater killifish that lived in the lake biome as the system's only fish. It grazed algae and plant material, but its larger role in miniBIOTA was predation on Daphnia and other microcrustaceans. It was removed on April 5, 2026 to let that middle layer recover and rebuild the lake food web.

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Identity & Origin +

Common Name: Flagfish
Scientific Name: Jordanella floridae
Realm: Freshwater
Biome: Freshwater Lake
Introduction Method: Intentional Seeding
Date First Introduced: June 03, 2024
Source / Origin: One male flagfish was introduced to the Freshwater Lake on June 3, 2024 and remained there until April 5, 2026, when it was moved to an outdoor tank with more natural food availability.

Section Notes

The American Flagfish is a Florida native pupfish/killifish found in vegetated freshwater habitats, with occasional brackish tolerance. Current species name updated to Jordanella floridae during the May 1, 2026 review. Older project records may show Jordanella florida without the final e.

Population Dynamics +

Current Estimated Population: 0
Population Status: Removed
Carrying Capacity Status: Below Capacity
Date Last Observed: April 05, 2026

Section Notes

The miniBIOTA population is currently zero. One male lived in the Freshwater Lake until April 5, 2026, when it was removed as a deliberate management decision. The fish was healthy enough to move; the goal was to reduce predation pressure and give Daphnia, copepods, amphipods, and shrimp larvae a better chance to function as the lake's middle trophic layer.

Trophic Ecology +

Trophic Level: Omnivore
Feeding Niche / Method: Algae grazer and small-invertebrate predator
Dietary Inputs: Algae, plant material, detritus, small crustaceans, worms, insects, and other small invertebrates.
Known Predators: None observed in miniBIOTA.

Section Notes

In natural Florida waters, flagfish are omnivores in vegetated freshwater habitats. In miniBIOTA, one male had an outsized effect because the lake was small and closed: its predation kept Daphnia and other microcrustaceans from becoming a visible energy-transfer layer between algae and larger consumers.

Environmental Tolerances +

Temperature Range: 18-22 C
Flow / Aeration Preference: Slow-moving or still freshwater with dense vegetation and surface cover.

Section Notes

Freshwater species with some brackish tolerance. In miniBIOTA, it was kept in the Freshwater Lake and later moved outdoors after its predation pressure became too strong for the sealed lake food web.

Life Cycle & Reproduction +

Reproductive Strategy: Egg-laying killifish; eggs are deposited on plant or algae-covered surfaces, and males may guard and fan eggs.
System Reproduction Status: No Signs of Breeding
Growth Rate: Unknown

Section Notes

Only one male was kept in miniBIOTA, so breeding was not possible within the system.

Ecological Role & Symbiosis +

Ecological Role: Predator
Microhabitat Preference: Vegetated freshwater, plant edges, surface cover, and open hunting paths through the water column.

Section Notes

The flagfish became a useful lesson in scale. In a larger vegetated pond, its algae grazing and small-prey hunting can be part of a balanced food web. In the sealed lake biome, one fish was enough to suppress the microcrustacean layer, so removal became the better ecological decision.

Freshwater

A still freshwater habitat where submerged plants, suspended algae, microcrustaceans, shrimp, snails, and crayfish are reorganizing after fish removal.

Flagfish

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Biomes This Species Lives In

Freshwater Lake

Fish removal reopens the lake food web

Daphnia Need Shelter Before They Can Control Algae

New Freshwater Plants Immediately Become Food

Duckweed Declines While Water Spangles Hold On

Duckweed Trial Meets Immediate Grazing Pressure

Moved Systems Reconnect While Organism Losses Are Checked

Plants and Grasshoppers Added to Increase Productivity

Ecological Web

Energy Flow

Flagfish

Biomes This Species Lives In

Fish removal reopens the lake food web

Daphnia Need Shelter Before They Can Control Algae

Ecological Web

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