Bull Minnow Aquaculture

Kaylee D’Aloise

Taxonomy

Scientific Name:

-Fundulus grandis

Common Names:

-gulf Killifish

-mud minnows

-mudfish

-bullminnow

Economic Importance

Sold as live bait Mostly used to catch flounder, redfish, and speckled

trout

Prices are about $7-10/lb for wholesale and $12-20/lb for retail

Local bait dealers mostly rely on harvest of wild stock to supply market

Mostly grow experimentally still, other bait minnows are grown on much larger scales.

Life Cycle and Larval Stages

Little is known about larval cycle, but salinities of 5 to 40ppt result in better larval survival than higher or lower salinities.

As adults they spawn with the tidal cycles

They can live up to 4 years old, however rarely do because of predation and harvest

Live in shallow waters of oyster bars, salt marsh pool, bayous and tidal creeks

Females usually larger than males

Reproduction in Captivity

Spawn readily in captivity

Stocked in a 2:1 ratio of female to male

External fertilization

Spawn March to October but peak in March-April

Have adhesive eggs that attach to spawning mats

Water must be above 68 degrees Fahrenheit

Production Methods Used

Grown successfully in ponds in several southern coastal states

Most information comes from experimental facilities

Have been grown in RAS but good growth was hard to achieve with only artificial diets

Best production method is a three-phase systemSpawing pondHatching pondGrow-out pond

Phase 1 – Spawning Pond

Pond stocked at 10,000 per acre

2:1 ratio of female to male

Water needs to be 68 Degrees Fahrenheit

Spawning nets around edge of pond and suspended in water

After one week they are moved into the phase 2 pond

Phase 2 – Hatching Pond

Pond must be filtered before mats put in

Treat pond for insects

1.5 million eggs can be stocked per acre, of which you can expect 1 million fry from

Eggs hatch in 2-3 weeks

Once fish reach 900 – 1,500 per pound they are moved to phase 3 the grow-out pond

Phase 3 – Grow-out Pond

The time needed to produce a certain size fish depends on the stocking density, so depending on what the market needs depends how you stock phase 3 pond

Stocking at 50,000 fish per acre produces 2.5 inch minnows in 5 weeks, while 100,000 per acre takes more than 6 weeks

Stocking around 200,000 per acre gives little growth rate and can be used for holding fish over winter

When they reach market size they are harvested by either seining or pond draining

Bull minnow trap for harvest

Feeds and Feeding

Bull minnows are omnivores and feed on whatever is available

Fry are fed finely ground minnow meal that is 28-32% crude protein at 5 pounds per acre per day

Phase 3 fish are fed floating feed twice daily at 10% stocked weight per day

Every week the average weigh is taken and feed adjusted, after one week it is dropped to 5% and so on

Water Chemistry and Environmental Requirements in

CultureTolerant to wide range of water qualities

Minimum salinity recommended is 3-5 ppt, any lower could affect spawning and disease resistance

High stocking rates might need aerators, a DO level generally above 4.0mg/L

Ponds should average 3 feet deep with smooth bottoms

Ponds free of aquatic vegetation

Advantages and Disadvantages

AdvantagesVery tolerant of water qualitiesLow mortality ratesLong-lasting on the hookGrow fast

Disadvantages Need large number of spawning females since females

produce low number of eggs (10-200 per spawn and up to 1,200 per season)

Very dependent on market demand and time of year Still a lot to learn in aquaculture of bull minnow

Sources

Auburn University Marine Extension & Research Center http://www.extension.org/mediawiki/files/2/24/Growing_Bull_Minnows_in_Alabama.pdf

Southern Regional Aquaculture Center https://srac.tamu.edu/index.cfm/event/getFactSheet/whichfactsheet/149/

Mississippi Agricultural and Forestry Experimental Station http://msucares.com/crec/aquabull.html

http://www.aces.edu/dept/fisheries/aquaculture/baitfish-minnow.php