Barren’s topminnow (Fundulus julisia)

Barren's topminnow swimming
Loading more images and videos...

Barren’s topminnow fact file

Barren’s topminnow description

GenusFundulus (1)

Discovered as recently as 1982, the Barren’s topminnow is considered to be one of the most endangered fish species in eastern North America (3). Breeding males are striking pale blue-green to yellow-green on the sides of the head and body, and marked with numerous scattered dark red spots. The upperside of the male’s body is olive, with a distinctive white to pale gold stripe running down the midline of the back from the head to the dorsal fin. The dark red spotting extends onto the fins, which are translucent blue, with white and orange bands next to the black fin borders. Females and juveniles are less brightly coloured, with brownish-grey sides marked with numerous dark brown spots, and yellow tinged lower fins (3).

Length: up to 7 cm (2)

Barren’s topminnow biology

Barren’s topminnow is an opportunistic predator, taking a variety of aquatic invertebrates, such as tiny freshwater crustaceans, midge larvae and snails, along with terrestrial insects that fall into the water or alight on the water surface (2) (3). Spawning takes place in the early spring, when the water temperature reaches 14 to 15 degrees Celsius. The numerous eggs produced by the female adhere to aquatic vegetation, such as fronds of freshwater algae, and are left to hatch unguarded (2) (3) (5). The lifespan of this species is typically two to three years (3).


Barren’s topminnow range

The Barren’s topminnow is found in the US state of Tennessee, where it occurs in the Caney Fork River (part of the Cumberland River drainage) and the Duck, and Elk Rivers (part of the Tennessee River drainage), in the central Barrens Plateau region. In 1984, this species was known from 14 sites, but by 1997 its range had declined to just 2 sites. Fortunately, as a result of reintroductions using captive-bred specimens, the Barren’s topminnow now occurs in several additional sites within its historic range (4).


Barren’s topminnow habitat

The Barren’s topminnow inhabits the margins of clear springs and streams, as well as well-vegetated pools (2) (3) (5).


Barren’s topminnow status

The Barren's topminnow is classified as Endangered (EN) on the IUCN Red List (1).

IUCN Red List species status – Endangered


Barren’s topminnow threats

With an extremely limited distribution, and an accordingly small population, the Barren’s topminnow is particularly vulnerable to extinction from both natural and artificial causes (3). In 1998, a drought at the pool where this species was discovered required the removal of the entire local population. The fish were housed in an artificial facility and re-released after heavy rains replenished the water (5). Along with natural incidents, habitat degradation and development are also significantly affecting this species (3) (5). Perhaps the most severe threat to this species, however, is the introduced non-native western mosquitofish Gambusia affinis (6) (7). Artificially introduced to control mosquitoes by preying on the aquatic larvae, this species has becomes widespread, and has invaded the range of the Barren’s topminnow (7). The invasive species preys on the larval and juvenile stages of Barren’s topminnow, resulting in catastrophic local population declines (6) (8).


Barren’s topminnow conservation

Though considered endangered by the state of Tennessee, the Barren’s topminnow does not currently receive Federal protection (3) (5). Fortunately, however, concerted efforts are being made to conserve this imperilled species. In 2001, the Barren’s topminnow Working Group was established, which has been responsible for implementing programmes to restock the Barren’s topminnow at over 24 sites throughout much of its historic range. While many restocking efforts appear to have proven successful, with successful wild breeding occurring, the presence of mosquitofish remains problematic (4). The group is therefore researching and implementing ways to minimise the impacts of the invasive species, including the creation of barriers around one pool occupied by this species to prevent the mosquitofish from entering (4) (5). The group is also undertaking studies to determine the effects of habitat loss and degradation (4). In order to address this threat, it is clear that land management practices encouraging the formation of open water habitats favoured by this species are necessary (3).

View information on this species at the UNEP World Conservation Monitoring Centre.

Find out more

To learn more about conservation of freshwater fish in the south-eastern United States visit:




This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:



Dorsal fin
The unpaired fin found on the back of the body of fish, or the raised structure on the back of most cetaceans.
Animals with no backbone, such as insects, crustaceans, worms, molluscs, spiders, cnidarians (jellyfish, corals, sea anemones), echinoderms, and others.


  1. IUCN Red List (August, 2013)
  2. FishBase (October, 2009)
  3. Johnson, A.B. and Bettoli, P.W. (2003) Threatened fishes of the world: Fundulus julisia Willams & Etnier, 1982 (Cyprinodontidae). Environmental Biology of Fishes, 68: 240 - .
  4. Call, G.P. (2008) Cooperative Conservation and Restoration of the Barrens Topminnow (Fundulus julisia) on the Eastern Highland Rim, Tennesee. Natural Areas Revival in Music City: Tuning into a Changing Climate and Biological Invasion, 35th Annual Natural Areas Conference, October 14-17, 2008, Nashville, Tennessee.
  5. Conservation Fisheries (October, 2009)
  6. Goldsworthy, C.A. and Bettoli, P.W. (2006) Growth, Body Condition, Reproduction and Survival of Stocked Barrens Topminnows, Fundulus julisia (Fundulidae). The American Midland Naturalist, 156: 331 - 343.
  7. Laha, M. and Mattingly, H.T. (2006) Identifying environmental conditions to promote species coexistence: an example with the native Barrens topminnow and invasive western mosquitofish. Biological Invasions, 8: 719 - 725.
  8. Laha, M. and Mattingly, H.T. (2007) Ex situ evaluation of impacts of invasive mosquitofish on the imperiled Barrens topminnow. Environmental Biology of Fishes, 78: 1 - 11.

Image credit

Barren's topminnow swimming  
Barren's topminnow swimming

© J. R. Shute / Conservation Fisheries Inc.

J R Shute
Conservation Fisheries Inc
3424 Division St
United States of America
Tel: 865 521 6665


Link to this photo

Arkive species - Barren’s topminnow (Fundulus julisia) Embed this Arkive thumbnail link ("portlet") by copying and pasting the code below.

Terms of Use - The displayed portlet may be used as a link from your website to Arkive's online content for private, scientific, conservation or educational purposes only. It may NOT be used within Apps.

Read more about



MyARKive offers the scrapbook feature to signed-up members, allowing you to organize your favourite Arkive images and videos and share them with friends.

Play the Team WILD game:

Team WILD, an elite squadron of science superheroes, needs your help! Your mission: protect and conserve the planet’s species and habitats from destruction.

Conservation in Action

Which species are on the road to recovery? Find out now »

Help us share the wonders of the natural world. Donate today!


Back To Top