Keeping the Broadstripe Topminnow

The Broadstripe Topminnow (Fundulus euryzonus) occurs only in the Lake Ponchartrain drainage system of Mississippi and Louisiana, primarily in the Amite and Tangipahoa Rivers. Both Rivers begin in Mississippi, then flow South until reaching the Northern Shores of Lake Ponchartrain.

Unlike its close relatives, the Blackstripe Topminnow (F. notatus) and the Blackspotted Topminnow (F. olivaceous), the Broadstripe has a much broader lateral band. Moreover, the Broadstripe's lateral band is much broader than that of the other two species and has a purplish-black hue when observed in sunlight. The Broadstripe Topminnow reaches a length of 3 1/4 inches.

Although all three species share the same range, the Broadstripe prefers streams, while its two close relatives thrive in lakes and ponds lacking current. In a stream habitat, however, the Broadstripe Topminnow will tend to concentrate in areas having a depth of three feet or more, while F. olivaceus and F. notatus will frequent shallower, faster flowing areas over sand bars and around log jams.

While it is possible to collect this species with a seine, a dip net usually works best. The Broadstripe Topminnow is extremely alert and will avoid capture by darting into snags and brushpiles at most attempts to corral them with a seine. Minnow traps, also, do not seem to work very well.

Look for them as you quietly wade into the deeper parts of the stream. They will pause for just an instant after they've spotted you before heading for cover. Your only chance at capture will be to take advantage of this brief hesitation. Swing the dip net ahead of them and retrieve it as fast as you can. Make a quick check of your net; if you missed, look around. If they haven't made it to cover, they may be holding just out of range of your net, and you can try again. If you don't see any, be patient and remain still for a minute or two. They'll soon resurface.

After you've captured a few and acclimated them to aquarium life, they will readily accept flake food, frozen brine shrimp, and virtually any live food your offer them. The Broadstripe Topminnow will spawn in bottom mops and the eggs should be removed and incubated at 70 to 75 degrees Fahrenheit for about 14 days. Methylene blue will clear up any fungus problems.

The fry generally reach maturity in 6 to 8 months. The males become territorial at an early age. If they become too aggressive, you will need to remove them from the rearing tank.

The Broadstripe Topminnow is a unique killifish that should be kept and studied by all who are interested in the North American species of the Fundulidae group.

I'd like to offer my sincere thanks to Dr. Robert C. Cashner of the University of New Orleans, who described this species and to graduate student Tom Blanchard of Louisiana State University. Both have contributed much to the content of this article and to our knowledge of this fish. Mr. Blanchard has produced hybrids of male F. olivaceus with female F. euryzonus and also of male F. euryzonus with female F. olivaceus.

Used with permission. Article copyright retained by author.