(DRAFT) - Taxonomy
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
TAXONOMY
NAME - DACE, MOAPA
OTHER COMMON NAMES - DACE and MOAPA
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - OSTEICHTHYES,
ORDER AND SUBORDER - CYPRINIFORMES,
FAMILY AND SUBFAMILY - CYPRINIDAE,
GENUS AND SUBGENUS - MOAPA,
SPECIES AND SSP - CORIACEA,
SCIENTIFIC NAME - MOAPA CORIACEA
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Moapa Dace
Moapa coriacea Hubbs and Miller, 1948
KINGDOM: Animal GROUP: Fish
PHYLUM: Chordata CLASS: Osteichthyes
ORDER: Cypriniformes FAMILY: Cyprinidae
An olivaceous minnow with blotches on the side, a white belly and
a dark spot at the base of the caudal fin rays, Moapa grows to about
4 inches in length. Pharyngeal teeth are uniserial, numbering
typically 5-4; they are hooked and have crushing surfaces. The head
is short and subconical with a nearly horizontal mouth and relatively
thick lips. The maxillary extends posteriorly to the front margin of
the eye. The dorsal fin originates directly over or slightly
posterior to the insertion of the pelvic fins. Dorsal fin rays, and
pelvic fins typically have 8, occasionally 7 or 6 rays. Caudal fin is
forked and equilobate. The peritoneum is black and the intestine
short, about equalling body length. Scales are deeply imbedded,
giving the epidermis a leathery appearance.
The monotypic genus was described in 1948 (07). It has remained
unconfused taxonomically. The genus probably originated from an
ancestor shared with Agosia. It also bears some resemblance to
Taxonomy - 1 (DRAFT) - Taxonomy
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
Rhinchthys and Gila (07).
The holotype (UMMZ 143186) and numerous paratypes are deposited
at the University of Michigan Museum of Zoology. Other collections
are maintained at Brigham Young University, University of Nevada - Los
Vegas and University of Nevada - Reno. The species is illustrated
photographically by Hubbs and Miller (07), and La Rivers (11).
Taxonomy - 2 (DRAFT) - Status
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
STATUS
Coded Status
E: Federal Endangered
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Moapa dace (Moapa coriacea) has been designated an
Endangered species pursuant to the Endangered Species Act of 1973
(50 CFR 17.11; P.L. 93-205, 87 Stat. 884; 16 U.S.C. 1531-1540), as
amended. The species has this status wherever found including the
State of Nevada.
This species is protected by the Lacey Act (P.L. 97-79, as
amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to import,
export, transport, sell, receive, acquire, or purchase any wild
animal (alive or dead including parts, products, eggs, or offspring):
(1) in interstate or foreign commerce if taken, possessed,
transported or sold in violation of any State law or
regulation or foreign law; or
(2) if taken or possessed in violation of any U.S. law,
treaty, or regulation or in violation of Indian tribal law.
It is also unlawful to possess any wild animal (alive or dead
including parts, products, eggs, and offspring) within the U.S.
territorial or special maritime jurisdiction (as defined in
18 U.S.C. 7) that is taken, possessed, transported, or sold in
violation of any State law or regulation, foreign law, or Indian
tribal law.
RESPONSIBLE FEDERAL AGENCIES:
USFWS -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
All Federal agencies have responsibility to ensure that any
action authorized, funded, or carried out by that agency is not likely
to jeopardize the continued existence of the species or result in the
destruction or adverse modification of Critical Habitat (50 CFR 402),
and to utilize their authorities to carry out programs for the
conservation of the species.
STATE STATUSES AND LAWS:
STATE: Nevada
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: Nevada Department of Wildlife
STATE STATUTE: Nev. Rev. Stat. 501.181, 501.351, 503.584,
503.585, 503.587, and 503.589
Status - 1 (DRAFT) - Status
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
The Moapa dace is listed as endangered in the IUCN Red Data Book,
vol. 4, 1977, and as rare in the Western Hemisphere Convention Annex
(1967).
ECONOMIC STATUSES:
None.
67/03/11:32 FR 29567/29577 - Listed as Endangered (1966 Act).
70/08/25:35 FR 13519/13520 - Proposed listing as Endagered (1969 Act).
70/10/13:25 FR 16047/16048 - List of Endangered species.
79/05/21:44 FR 29567/29577 - Five year review.
85/07/22:50 FR 29901/29909 - Five year review.
Status - 2 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
INLAND AQUATIC
LAND USE -
Commercial and Services
Cropland and Pasture
Streams and Canals
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Palustrine SS1
Palustrine EM
Palustrine AB2
Riverine, upper perennial SB3
Riverine, upper perennial SB2
Riverine, upper perennial SB1
COMMENTS ON HABITAT ASSOCIATIONS -
General and physical characteristics of the habitat occupied
by Moapa dace have been described by Eakin (06), U.S. Fish and
Wildlife Service (15,17), and Deacon and Bradley (04). The species
is restricted to warm springs, their outflows and the warm waters of
the upper mainstream Muddy River. The some 11 spring provinces in the
area discharge approximately 1.13 cubic meter per sec. into streams
and irrigation canals. Velocity flow is variable, but in may areas
can be swift. Temperature at most spring sources is a nearly constant
32 deg Celsius (04,06,07), cooling to 28 deg Celsius in the mainstream
just above a low head dam located about 1000 m downstream from the
source. Below the dam and in some slow, ponded, or backwater areas
above the dam, water temperature becomes more variable as a function
of air temperature variation. Moapa dace are usually found in waters
no cooler than 27 deg Celsius, although they have been taken below the
low head dam in waters as cool as 19.5 deg Celsius (04).
Dissolved oxygen concentrations in Moapa dace habitat has been
recorded between 1.6 and 8.9 ppm (05) although concentrations below
2.4 seem to be uncommon (08,10,15). Other physical and chemical
measurements are given by Deacon and Bradley (04), Eakin (06) and U.S.
Fish and Wildlife Service (15). They show total dissolved solids near
630 mgm/l, specific conductance of about 915 micro-ohms/cm, total
alkalinity of about 230, and pH of 7.3-7.7. The primary cations are
sodium and calcium and the primary anions sulfate and calcium
carbonate. Turbidity has not been reported, but Hubbs and Miller (07)
emphasized that the species was taken only in clear, warm waters.
Deacon and Bradley (04) noted that turbidity increased rapidly after
the stream channel became well defined, and Scoppetone (14) noted that
turbidity in the upper main stream can be highly variable, with the
relatively rare periods of clear water coinciding with the temporary
interruption of irrigation. He concluded that much of the turbidity
in the upper mainstream results from irrigation return flows to the
river.
Streamside vegetation is dense throughout most of the Moapa dace
habitat, frequently forming a complete canopy over the stream and
filling the channel with snags and brush (01,04,15). Streamside
vegetation consists of ash, cottonwood, screwbean, willow, palm,
tamarisk, grape vines, and a variety of shrubs, grasses and herbs.
Relatively little emergent or submergent aquatic vegetation is present
Habitat Associations - 1 in the turbid, shaded, swift, waters. In slower, clearer waters
and other submergent and emergent aquatic vegetation occurs
(01,04,15).
Fishes associated with Moapa dace have been reported (01,02,03,
04,07,09,15). The Moapa White River springfish, Crenichthys
baileyi moapa is abundant in springs and more slowly moving waters.
The other native fishes, Gila robusta (the roundtail chub), and
Rhinichthys osculus (the speckled dace) are rare or absent throughout
the habitat of the Moapa dace. Prior to the introduction of exotic
species, the Moapa dace was doubtless dominant in the more swiftly
flowing waters. Today, the dace is nearly always outnumbered by the
shortfin molly, even in swift waters. The introduced snail,
Melanoides sp., is common. In addition, there are a variety of
invertebrates living in Moapa dace habitat.
Much of the land adjacent to Moapa dace habitat is used for
farming (hay and pasture) and ranching. There is also a resort
development (Desert Oasis) associated with one of the two springs
provinces.
Habitat Associations - 2 (DRAFT) - Food Habits
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
LIFESTAGE FOOD FOOD PART
General Arthropods
General Detritus
General Algae
Food Habits - 1 (DRAFT) - Environment Associations
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G
G Aquatic Features: Springs [flowing]
G Terrestrial Features: Downed logs
G
Environment Associations - 1 (DRAFT) - Life History
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
Food habits of Moapa dace are the subject of a study
by the U.S. Fish and Wildlife Service (15). Preliminary results
indicate that the species is predominantly carnivorous (gut length
about 0.96 of total body length). About 60% of the items in Mopa dace
stomachs were invertebrates, about 20% was detritus and about 15% was
filamentous algae. Direct observation of feeding indicates that the
species feeds relatively indiscriminantly on drift. They tend to
congregate at dawn and dusk in swift water near snags and dash up into
the current to pick off drift material passing by (14). Observations
of feeding behavior in pool habitats indicate Moapa dace will consume
benthic invertebrates directly off the bottom. Larvae, living in
shallower, more slowly moving water, probably feed on the much smaller
micro-crustacea.
HOME RANGE/TERRITORY:
Moapa dace do not appear to exhibit territoriality. They
congregate in swift water near snags for feeding. The fact that these
congregations seem to exhibit considerable variability in size and
specific locations in the stream suggests some independent, individual
movement and, an as yet undefined, home range.
PERIODICITY:
Scoppetone (14) indicates that drift feeding, discussed earlier,
tends to be a crepuscular activity.
MIGRATION PATTERNS:
Fish traps placed to block the downstream extent of one tributary
showed that some emmigration occurred from February through August. A
distinct peak in emmigration occurred in May. Mean size of the
emmigrants was 19.9 mm, with a range of 10-35 mm (15). This suggests
that most emmigrants are young fish.
COVER/SHELTER REQUIREMENTS:
Preliminary information (15) suggests that adult Moapa dace
occupy the full range of habitats available in the headwaters
of Muddy River. They are essentially the only fish species
regularly found in stream velocities above about 18 cm/sec.
Habitats with velocities to 24 cm/sec. have been examined and
regularly contain Moapa dace. Larvae seem restricted to stream
velocities below about 9 cm/sec. and are most common in velocities
below about 3.5 cm/sec.
Adult Moapa dace occur in water to at least 130 cm deep and are
most common at near 60 cm depth. Larvae occur in water to about 100
cm in depth and are most common below about 30 cm.
Adult Moapa dace occupy habitats in which dissolved oxygen
concentrations range from about 2.5-6.0 ppm (15) and probably are not
limited by higher dissolved oxygen concentrations. Larvae have been
observed in dissolved oxygen concentrations from about 4.5-7.5 ppm
(15).
Life History - 1 (DRAFT) - Life History
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
REPRODUCTIVE SITE REQUIREMENTS:
Moapa dace were observed spawning on a sandy substrate in water
depth of 15-19 cm and near-bed velocity of 3-9 cm/sec. (15).
REPRODUCTIVE CHARACTERISTICS:
Moapa dace can reproduce throughout the year in the nearly
constant temperatures of their habitat. Peak reproduction probably
occurs from February to April followed by peak emmigration of the
young in May (15).
Preliminary measurements of fecundity indicate a range of 97-386
eggs produced per adult female (15).
PARENTAL CARE:
There is no indication of parental care during or after egg
deposition (15).
POPULATION BIOLOGY:
Hubbs and Deacon (09) noted the introduction of the shortfin
molly into Moapa habitat. Wilson (16) suggested that increased
parasitism may have followed the molly introduction and Deacon and
Bradley (04) suggested that a decline in abundance followed by an
increased abundance may have followed the introduction of the molly.
Cross (03) documents that by 1975, there was again clear evidence
that distribution and abundance of Moapa dace had declined.
The U.S. Fish and Wildlife Service study (15) indicates that the
Moapa dace occupies only 10% of its original range. The study
suggests that the most important factor limiting distribution and
abundance of Moapa dace within its former range may be turbidity
caused by irrigation return flows into the formerly clear water.
The Moapa dace may have its feeding ability severly curtailed by the
increased turbidity and that population decline as a consequence of
the biotic interactions has probably been minimal.
SPECIES INTERRELATIONSHIPS:
See POPULATION BIOLOGY above.
OTHER LIFE HISTORY DESCRIPTORS:
None.
Life History - 2 (DRAFT) - Management Practices
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Maintaining/Controlling Water Flow
Beneficial Controlling water levels
Beneficial Land Acquisition
Beneficial Reforestation
Beneficial Transplanting wild animals
Beneficial Controlling/Removing Exotic Vertebrates
Adverse Low Gene Pool
Existing Low Gene Pool
Adverse Parasites
Existing Parasites
Adverse Predation
Existing Predation
Adverse Siltation
Existing Siltation
Adverse Irrigating
Existing Irrigating
Adverse Dredging
Existing Dredging
Adverse Competition
Existing Competition
Adverse Exotic/Feral/Introducted Species
Existing Exotic/Feral/Introducted Species
Adverse
Existing
COMMENTS ON MANAGEMENT PRACTICES -
The Moapa dace was common throughout a diversity of warm,
clear water habitats in the headwaters of the Moapa River about 1960
(07,11,12). La Rivers (11) suggested that in spite of probable
competition and predation from introduced mosquitofish (Gombusia
affinis) and bullfrogs (Raha catesbeiana), Moapa remained common.
Predation is considered to be of little concern to a healthy
population, but in the case of these fluctuating numbers predation
becomes a burdon on the Moapa dace's survival and recovery (17).
Studies indicate there are strong relationships between the decline
and the introduction of the shortfin molly (Poecila mexicana), which
occurred around 1963, and extensive habitat modification that occurred
20 to 30 years ago (i.e agricultural development) (17). Deacon and
Bradley (04) indicated that abundance had probable declined by the
early 1960's, but then increased again in the mid-1960's. Cross (03)
showed an apparent decline again in the early 1970's. Hubbs and
Deacon (09) noted the introduction of the shortfin molly into Moapa
dace habitat. Wilson (16) suggested that increased parasitism may
have followed the molly introduction and Deacon and Bradley (04)
suggested that a decline in abundance followed by an increased
abundance may have followed the introduction of the molly.
Cross (03) documents that by 1975, there was again clear evidence
that distribution and abundance of Moapa dace had declined. The
Management Practices - 1 (DRAFT) - Management Practices
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
apparent decline in abundance for Moapa has been tentatively
attributed, at least in part, to competitive interactions with
introduced exotic species (17), parasites (commonly associated with
aquarium fishes and introduced through these exotic fish) (01,09,11,
13,17), and declining water quality (chemical parameters and physical
parameters) from channelization and irrigation for agricultural
development (03,17). More recent work by Gary Scoppetone (14) of the
U.S. Fish and Wildlife Service indicates that increased turbidity
resulting from irrigation may be the most significant factor in the
decline of the species. Stomach analysis demonstrates that Moapa
feeds primarily on invertebrates (15). Observations of feeding
behavior suggest that the species feeds on the drift organisms and is
a sight feeder (15). Increased turbidity would therefore severely
restrict the species' ability to feed. U.S. Fish and Wildlife Service
(15) estimates that Moapa occurs in less than 10 percent of its
former range. Areas in which Moapa remain relatively abundant include
the least disturbed sites in the headwaters (15).
Future threats to the species include additional water
development for irrigation or any activity that would increase the
turbidity, reduce the low gene pool, channelize the stream course or
add exotic species to the stream in the headwaters of the Muddy River.
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1983. Moapa Dace Recovery Plan.
U.S. Fish and Wildlife Service, Portland, OR. 32 pp.
The primary objective of the Moapa Dace Recovery Plan is to
restore and maintain the Moapa dace in its native habitat through
management practices. Reclassification to Threatened could be
considered with the protection and rehabilitation of self-sustaining
populations at three springs. In addition to attaining the Threatened
status, life history and ecology studies must have been completed.
The recovery activities necessary to acheive the objective:
1. Determine characteristics of self-sustaining populations
(recovered) through reproductive studies, feeding habitat studies,
age and growth studies, parameters of preferred habitat, population
dynamics studies, ecological relationships with other fish and
aquatic species;
2. Reestablish ecosystems by securing essential habitats and applying
life history and ecological information to restoration and
enhancement of secured habitats;
3. Reintroduction to restored habitat by transplanting wild
individuals;
4. Protect populations and discharging aquifer with fences, signs,
fish barriers (and also remove any exotic species detrimental to
the survival of this species), maintain water table and flow, and
enforcement of Endangered species laws and regulations;
5. Implement public information and education programs.
Management Practices - 2 (DRAFT) - References
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Bradley, W.G. and J.E. Deacon. 1967. The biotic communities of
southern Nevada. Nev. State Mus. Anthr. Papers 13(4):201-295.
02 Courtenay, W.R., J.E. Deacon, D.W. Sada, R.C. Allan, and G.L.
Vinyard. 1985. Comparative status of fishes along the course of
the pluvial White River, Nevada. S.W. Nat. [In press.]
03 Cross, J.N. 1976. Status of the native fish found in the Moapa
River, Clark County, Nevada. Trans. Am. Fish. Soc. 105(4):503-508.
04 Deacon, J.E. and W.G. Bradley. 1972. Ecological distribution of
the fishes of Moapa (Muddy) River in Clark County, Nevada. Trans.
Am. Fish. Soc. 101(3):408-419.
05 Deacon, J.E. and B.L. Wilson. 1967. Daily activity cycles of
Crenichthys baileyi, a fish endemic to Nevada. S.W. Nat. 12(1):
31-44.
06 Eakin, T.E. 1964. Ground water appraisal of Coyote Spring and
Kane Spring Valleys and Muddy River springs area. Lincoln and
Clark Co., Nevada. Ground-water Res. - Recon. Ser. 25:1-39.
07 Hubbs, C.L. and R.R. Miller. 1948. Two relect genera of Cyprinid
fishes from Nevada. Occas. Papers, Univ. Mich. Mus. Zool. 507:1-30.
08 Hubbs, C., R.C. Baird, and J.W. Gerald. 1967. Effects of
dissolved oxygen concentration and light intensity on activity
cycle of fishes inhabiting warm springs. Amer. Mill. Nat.
77(1):104-115.
09 Hubbs, C. and J.E. Deacon. 1964. Additional introductions of
tropical fishes into southern Nevada. S.W. Nat. 9(4):249-251.
10 Hubbs, C. and W.F. Hettler. 1964. Observations on the toleration
of high temperatures and low dissolved oxygen in natural waters by
Crenichthys baileyi. S.W. Nat. 9(4):245-248.
11 La Rivers, I. 1962. Fishes and fisheries of Nevada. Nev. Fish
and Game Comm., Carson City. 782 pp.
12 Miller, R.R. 1977. Pers. comm. Biology Depot., Univ. of Mich.
13 Minckley, W.L. and J.E. Deacon. 1968. Southwestern fishes and
enigma of "endangered species". Sci. 159(3822):1424-1432.
14 Scoppetone, Gary. 1985. Pers. comm. USFWS, Reno, NV.
15 U.S. Fish and Wildlife Service. 1984. Life history and ecological
requirements of the Moapa dace (Moapa coriacea) Ann. Rept., Nat.
Fish. Res. Center, Great Basin Complex Off., Reno,
NV. 40 pp.
16 Wilson, B.L., J.E. Deacon, and W.G. Bradley. 1966. Parasitism in
the fishes of the Moapa River, Clark Co., Nevada. Trans. Calif-Nev
Sect. of the Wildl. Soc., 1966:12-23.
17 U.S. Fish and Wildlife Service. 1983. Moapa Dace Recovery Plan.
U.S. Fish and Wildl. Serv., Portland, OR. 32 pp.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Cross, J.N. 1976. Status of the native fish found in the Moapa
River, Clark County, Nevada. Trans. Am. Fish. Soc. 105(4):503-508.
02 Deacon, J.E. and W.G. Bradley. 1972. Ecological distribution of
References - 1 (DRAFT) - References
Species DACE, MOAPA
Species Id ESIS251008
Date 14 MAR 96
the fishes of Moapa (Muddy) River in Clark County, Nevada. Trans.
Am. Fish. Soc. 101(3):408-419.
03 Hubbs, C.L. and R.R. Miller. 1948. Two relect genera of Cyprinid
fishes from Nevada. Occas. Pap., Univ. Mich. Mus. Zool. 507:1-30.
04 U.S. Fish and Wildlife Service. 1984. Life history and ecological
requirements of the Moapa dace (Moapa coriacea). Ann. Rept., Nat.
Fish. Res. Center, Great Basin Complex Off., Reno, NV. 40 pp.
References - 2