Cyprinodon variegatus

Range includes coastal North America from Massachusetts to Yucatan Peninsula; also the West Indies (e.g., Bahamas, Grand Cayman Island; Jamaica) (Burgess and Franz 1989). The species is introduced and established in the Pecos River in western Texas.

Massachusetts, USA to northeastern Mexico

occurs (regularly, as a native taxon) in multiple nations

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Range includes coastal North America from Massachusetts to Yucatan Peninsula; also the West Indies (e.g., Bahamas, Grand Cayman Island; Jamaica) (Burgess and Franz 1989). The species is introduced and established in the Pecos River in western Texas.

Southern U.S.A. and Mexico [this subspecies].

Found both in brackish and salt water. Atlantic coast of the United States, Cape Cod to Mexico.

Length: 5 cm

Maximum size: 75 mm TL

to 9.0 cm TL (male/unsexed).

nektonic

Habitat and Ecology

Systems

• Freshwater
• Marine

Habitat Type: Freshwater

Comments: This fish is usually near vegetation in relatively shallow brackish or fresh water of bays, inlets, salt marshes, lakes, or tidal rivers. It may be abundant where the bottom is at least partially sandy, emergent vegetation is lacking, and there is little current or wave action. It tolerates high temperature and salinity. Rarely does it occur far inland except in peninsular Florida. Eggs sink and stick together in clumps by numerous threads (Thomson et al. 1978).

Depth range based on 12 specimens in 2 taxa.
Water temperature and chemistry ranges based on 4 samples.

Environmental ranges
  Depth range (m): 0 - 5
  Temperature range (°C): 26.770 - 27.399
  Nitrate (umol/L): 0.691 - 1.225
  Salinity (PPS): 35.753 - 36.481
  Oxygen (ml/l): 4.541 - 4.638
  Phosphate (umol/l): 0.051 - 0.201
  Silicate (umol/l): 1.497 - 3.684

Graphical representation

Depth range (m): 0 - 5

Temperature range (°C): 26.770 - 27.399

Nitrate (umol/L): 0.691 - 1.225

Salinity (PPS): 35.753 - 36.481

Oxygen (ml/l): 4.541 - 4.638

Phosphate (umol/l): 0.051 - 0.201

Silicate (umol/l): 1.497 - 3.684
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Benthopelagic; freshwater; brackish; marine. Occurs in hypersaline lagoons and connecting channels. Found on muddy bottoms in turbid waters.

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Comments: Mainly a vegetarian (Thomson et al. 1978).

Omnivorous, diet consisting on vegetable matter, foraminifera, shrimps and other small crustacea, small mollusks, and small fish.

Cyprinodon variegatus (Sheepshead minnow) is prey of:
Odostomia seminuda
Acanthocitona pygmaea
Hylina veliei
Spirals
Nudibranchia
Polinices
Terebra
Seila adamsi
Epitonium albidum
Opalia hotessieriana
Natica pusilla
Urosalpinx perrugata
Busycon spiratum
Marginella aureocincta
Marginella apicina
Marginella bella
Turbonilla dalli
Turbonilla hemphilli
Sciaenops ocellatus
Lophodytes cucullatus
Tringa melanoleuca
Catoptrophorus semipalmatus
Larus argentatus
Larus delawarensis
Larus atricilla
Sterna forsteri
Haliaeetus leucocephalus
Circus cyaneus
sediment POC

Based on studies in:
USA: Florida (Estuarine)

This list may not be complete but is based on published studies.

Cyprinodon variegatus (Sheepshead minnow) preys on:
Micro-epiphytes
algae
Nauplii2
Nauplii1
Foraminifera
Nematoda
Polychaeta
Harpacticoida
Pycnogonidae
Acartia tonsa
Elasmopus levis
Lembos rectangularis
Acunmindeutopus naglei
Melita
Synchelidium
Ampithoe longimana
Cymadusa compta
Batea catharinensis
Listriella barnardi
Lysianopsis alba
Caprella penantis
bacteria
meiofauna
Amphipoda

Based on studies in:
USA: Florida (Estuarine)

This list may not be complete but is based on published studies.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

Comments: This species is represented by a large number of occurrences (subpopulations).

>1,000,000 individuals

Comments: Total adult population size is unknown but very large (exceeds 1,000,000). This species is common in much of its range.

Spawns in spring and summer. Female may spawn at intervals several times during season. Eggs hatch in 5-6 days (Thomson et al. 1978).

Oviparous. Spawning takes place in shallow water from April to September, the eggs maturing a few at a time, so that any given female spawn at intervals throughout the season.The eggs sink and stick together in clumps by numerous threads. Eggs are 1.2 to 1.4 mm. in diameter, with one large oil globule and many minute ones. Incubation takes 5 or 6 days, Upon hatching the larvae are 4 mm long and show alternate light and dark crossbands. At a length of 9 mm all the fins are formed, and at 12 mm the fry show most of the characters of the parents.

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Population

Population Trend

Global Short Term Trend: Relatively stable (=10% change)

Comments: Trend over the past 10 years or three generations is uncertain but likely relatively stable.

Major Threats

Comments: No major threats are known.

Conservation Actions

Comments: Has been used in carcinogenesis testing (Metcalfe 1989).

Species Impact: Introduced C. VARIEGATUS have negatively impacted native gene pool of C. PECOSENSIS; apparently between 1980 and 1984, C. VARIEGATUS was introduced into Pecos River in Texas; by 1985, hybrid swarm of C. PECOSENSIS and C. VARIEGATUS occupied roughly one-half of historic range of PECOSENSIS (Echelle and Connor 1989).