(DRAFT) - Taxonomy
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
TAXONOMY
NAME - MINNOW, LOACH
OTHER COMMON NAMES - MINNOW, LOACH; DACE and BROWN
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - OSTEICHTHYES,
ORDER AND SUBORDER - CYPRINIFORMES,
FAMILY AND SUBFAMILY - CYPRINIDAE,
GENUS AND SUBGENUS - TIAROGA,
SPECIES AND SSP - COBITIS,
SCIENTIFIC NAME - TIAROGA COBITIS
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Loach Minnow
Tiaroga cobitis Girard, 1856
KINGDOM: Animal GROUP: Fish
PHYLUM: Chordata CLASS: Osteichthyes
ORDER: Cypriniformes FAMILY: Cyprinidae
The loach minnow, Tiaroga cobitis, is an elogate, somewhat
fusiform minnow that reaches a maximum total length (TL) of about
80 mm (01). The ventral surface is somewhat flattened, the body
streamlined, eyes are placed high on the head, and the gas bladder is
reduced, attributes apparently relating to its use of benthic,
swiftwater microhabitat. The mouth is small and nearly oblique.
Scales are somewhat reduced or absent except on the lateral portion of
the body. Lateral line scales average about 65, dorsal and anal fin
rays are eight and seven, respectively, and pharyngeal teeth are in
two rows, 1,4-4,1 (02). Coloration is olive-green dorsally, and
blotched with darker pigment (02,03,04). The sides are lighter and
the ventral side is white to dirty-white. There is also a distinctive
light band on the base of the caudal fin that nearly surrounds the
dark basicaudal spot. Breeding males develop an intense red color
ventrally and on the lips, females are much less intensely colored.
Taxonomy - 1 (DRAFT) - Taxonomy
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
Breeding coloration and sexual dimorphism in loach minnow have been
described (03). Small breeding tubercles develop over the head, body,
and pectoral fins of male loach minnow, breeding females have a
scattering of tubercles on the head (03).
The loach minnow is one of two endemic genera in the Gila River
basin (the other is Meda). Its overall appearance is similar to that
of fish in the genus Rhinichthys. It is presumed that the loach
minnow is derived from the speckled dace, Rhinichthys osculus (05),
which seems plausible given the zoogeographic considerations.
Other investigators researching the relationships of North American
cyprinid genera have suggested that Tiaroga is phylogenetically closer
to the longnose dace, R. cataractae, on the basis of shared/derived
osteological characters, and that Tiaroga may more logically be placed
in the genus Rhinichthys (07). Other historical common names for the
loach minnow include brown dace (04).
The loach minnow was described from specimens taken in the San
Pedro River, Arizona (05,06). Type specimens are apparently extant
and housed at the Academy of Natural Sciences, Philadelphia. The
fish collections at Arizona State University, University of New
Mexico, and the University of Michigan Museum of Zoology have
substantial holdings of loach minnow specimens.
Taxonomy - 2 (DRAFT) - Status
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
STATUS
Coded Status
T: Federal Threatened
Game (Consumptive Recreational)
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The loach minnow (Tiaroga cobitis) has been designated a
Threatened 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
States of Arizona, New Mexico, and in Sonora Mexico.
Special rules concerning "take" for this species can be found in
50 CFR 17.44(q).
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.
BIA -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for management/recovery on Bureau of Indian Affairs
lands.
BLM -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control (43 CFR 4140). Also
responsible for management/recovery on Bureau of Land
Management lands.
Status - 1 (DRAFT) - Status
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
NPS -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for conservation (Nat. Park System Organic Act - 16
U.S.C. 1, 2-3)/management/recovery on National Park
Service lands. Taking, possessing, or disturbing of
Federally listed species is prohibited on NPS lands
(36 CFR 2.1, 2.2, and 2.3).
USFS -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for management/recovery on Forest Service lands. The
Forest Service is responsible for integrating
management, protection, and conservation of Federally
listed species into the Forest Planning process
(36 CFR 219.19 and 219.20). Management practices that
would cause detrimental changes in water temperature
or composition, water course blockage, or sediment
deposits within 100 feet of the edges of perennial
streams, lakes or other bodies of water are prohibited
(36 CFR 219.27(e)).
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: Arizona
DESIGNATED STATUS: Recognized Threatened, Group 3
ADMINISTRATIVE AGENCY: Arizona Game and Fish Department
STATE STATUTE: Admin. Rules and Regs. Sec. 12-4-319 and
12-4-210. Arizona Rev. Stat. Sec. 17-306.
STATE: New Mexico
DESIGNATED STATUS: Endangered, Group II
ADMINISTRATIVE STATUS: New Mexico State Game Commission
STATE STATUTE: New Mexico Stat. Annotated, Reg. 624, Sec.
17-2-41.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
This species was listed as vulnerable by the IUCN Red Data Book
in 1977 and the IUCN Red List of Threatened Animals (1986).
ECONOMIC STATUSES:
This species may have been used as a bait fish. It has value as
a component of New Mexico and Arizona's natural heritage of biotic
diversity.
Status - 2 (DRAFT) - Status
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
82/12/30:47 FR 58454/58460 - Notice of Review
85/06/18:50 FR 25380/25387 - Proposed Rule
86/10/28:51 FR 39468/39478 - Final Rule, Threatened
Status - 3 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
INLAND AQUATIC
SOCIETY OF AMERICAN FORESTRY TYPES
SAF TYPE STAGE CLOSURE
shrub--seedling
young tree
mature tree
Old Growth
Interior Ponderosa Pine shrub--seedling
Interior Ponderosa Pine young tree
Interior Ponderosa Pine mature tree
Interior Ponderosa Pine Old Growth
LAND USE -
Mixed Urban or Built-up Land
Cropland and Pasture
Herbaceous Rangeland
Shrub and Brush Rangeland
Mixed Rangeland
Deciduous Forest Land
Evergreen Forest Land
Mixed Forest Land
Streams and Canals
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Riverine, upper perennial UB2
Riverine, upper perennial UB1
Riverine, upper perennial SB2
Riverine, upper perennial SB1
Riverine, upper perennial RS
Riverine, upper perennial RB
Riverine, upper perennial FL2
Riverine, upper perennial FL1
Riverine, upper perennial BB2
Riverine, upper perennial BB1
COMMENTS ON HABITAT ASSOCIATIONS -
The loach minnow belongs to a suite of small- to moderate-
sized fishes that occur in mid-elevation (600-2200 m), cool to
warmwater, low gradient streams and rivers (01,02,10,14) in the Gila
River basin. These kinds of streams flow through a variety of
riparian habitats ranging from coniferous, Ponderosa pine-dominated
communities in upstream reaches, to Chihuahuan and Sonoran desertscrub
at lower elevations (19). Streamside vegetation includes willow,
cottonwood, sycamore, and a variety of shrubs, grasses, and sedges
(19). Loach minnows inhabit only perennial lotic habitats of moderate
temperature (generally < 32 degrees Celsius max.) and velocity that
are well aerated. Little is known regarding the salinity, pH,
conductivity, or turbidity tolerances of loach minnows. Currently
occupied habitats have moderate levels of the above parameters that
permit a wide variety of aquatic life to survive (01,02,10,14,20).
Microhabitat parameters of loach minnows have been extensively
investigated over geographic and ontogenetic variables (01). Spawning
Habitat Associations - 1 sites are under cobble-sized substrate particles located in shallow
(< 30 cm), moderate velocity (30 cm/sec) riffle and near-shore run
habitat (01,09). Geographic variation of spawning site selection (09)
is probably an artifact of habitat availability. Larval loach minnows
occupied shallow (mean depth = 10 cm), nearshore areas with low water
velocities (mean 8 cm/sec), and were usually over sand or gravel
substrate. Juvenile and adult loach minnows occupy distinctly
faster microhabitats (mean = 35 and 52 cm/sec, respectively), and
there was a positive relationship between fish size and water
velocity. Depths occupied by loach minnow remained similar between
juveniles and adults (mean=17 cm). These data (01) are not intended
to infer that loach minnows are actively using the water column and
maintaining in such water velocities. Loach minnows are poor swimmers
and sink rapidly because of their small gas bladder. Observations of
loach minnows in riffles indicate that the interstitial spaces in the
substrate are used as current breaks where fish are subject to little
or no current. Also, the large paired fins of the loach minnows are
held such that the current pushes the fish to the substrate helping it
maintain position. Although some geographic variation of microhabitat
use has been observed, this was an artifact of habitat availability
(01). Loach minnows in areas of limited habitat variability (e.g.,
Tularosa River) were found in a subset of water velocity microhabitats
that were utilized by loach minnow where a wider range of
microhabitats existed (e.g., Gila River in the Cliff-Gila Valley,
Forks area). Water depth occupied by these fish varied little between
any sites. Seasonal variation in microhabitat use is unknown.
Habitat Associations - 2 (DRAFT) - Food Habits
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
LIFESTAGE FOOD FOOD PART
General Bacteria
General Algae
General Zooplankton
General Crustaceans
General Arthropods
Food Habits - 1 (DRAFT) - Environment Associations
Species MINNOW, LOACH
Species Id ESIS252020
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 Aquatic Features: Pool areas
G Aquatic Features: Springs [flowing]
Environment Associations - 1 (DRAFT) - Life History
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
Loach minnows are primarily carnivorous and feed on a variety of
aquatic invertebrates (01,02,09,21). Most studies document a rather
restricted diet (01,21) with a preponderance of nymphal mayflies
(Ephemeroptera) and Diptera larvae in stomachs, and lesser amounts of
stoneflies (Plecoptera), caddisflies (Tricoptera). Most food items
consumed are small (2-5 mm), but vary widely with size of the fish.
Young fish ate predominantly small, immature Diptera (mostly
Chironomidae and Simulidae), while adult fish consumed more
Ephemeroptera nymphs (01,21). Loach minnows in Aravaipa Creek
consumed almost exclusively riffle-dwelling invertebrates (21). Loach
minnows ate more Diptera larvae in the winter (01,21) and spring (09),
but relied more heavily on mayfly nymphs the rest of the year. The
highest number of empty stomachs occurred in the winter, perhaps
indicating inactive feeding (01,09). Even though loach minnows have
restricted diets, they appear to consume those food items that are
most abundant in the stream, and have no trouble switching prey base
when a particular item becomes seasonally scarce (21). Thus, it is
doubtful that any particular food item is absolutely essential to
loach minnow survival. It is important, however, that a large and
healthy invertebrate community be maintained, especially in the spring
when habitats are inundated with large numbers of larval fish that
consume primarily the same kinds of food items (22). Loach minnows in
aquaria were difficult to maintain as they would not eat commercially
prepared food.
HOME RANGE/TERRITORY:
Little is known regarding the home range or territoriality in the
loach minnow. The possibility exists that male loach minnows are
polyganous (01) and they may defend spawning sites from intruders.
PERIODICITY:
There appears to be some level of periodicity in seasonal feeding
habits as loach minnows feed most actively during spring, summer, and
fall (01,09).
MIGRATION PATTERNS:
Little is known about the seasonal or daily movements of loach
minnows. They are presumably capable of inhabiting the same riffle
throughout life after hatching. Their small size and poor swimming
ability would also inhibit long range movements. Loach minnow larvae
dissappear from drift samples earlier (seasonally), and at smaller
sizes than spikedace, and are less susceptible to downstream transport
(14,22). Loach minnows do not exhibit erratic changes in distribution
and abundance, perhaps indicating less dispersal potential.
COVER/SHELTER REQUIREMENTS:
None are specifically known other than those described in the
HABITAT ASSOCIATIONS section. Microhabitat parameters of loach
minnows have been extensively investigated over geographic and
ontogenetic variables (01). Spawning sites are under cobble sized
Life History - 1 (DRAFT) - Life History
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
substrate particles located in shallow (< 30 cm), moderate velocity
(30 cm/sec) riffle and near-shore run habitat (01,09). Geographic
variation of spawning site selection (09) is probably an artifact of
habitat availability. Larval loach minnows occupied shallow (mean
depth = 10 cm), nearshore areas with low water velocities
(mean 8 cm/sec), and were usually over sand or gravel substrate.
Juvenile and adult loach minnows occupy distinctly faster
microhabitats (mean = 35 and 52 cm/sec, respectively), and there was a
positive relationship between fish size and water velocity. Depths
occupied by loach minnow remained similar between juveniles and adults
(mean = 17 cm). These data (01) are not intended to infer that loach
minnows are actively using the water column and maintaining in such
water velocities. Loach minnows are poor swimmers and sink rapidly
because of their small gas bladder. Observations of loach minnows in
riffles indicates that the interstitial spaces in the substrate are
used as current breaks where fish are subject to little or no current.
Also, the large paired fins of the loach minnows are held such that
the current pushes the fish to the substrate helping it maintain
position. Although some geographic variation of microhabitat use has
been observed, this was an artifact of habitat availability (01).
Loach minnows in areas of limited habitat variability (e.g., Tularosa
River) were found in a subset of water velocity microhabitats that
were utilized by loach minnow where a wider range of microhabitats
existed (e.g., Gila River in the Cliff-Gila Valley, Forks area).
Water depth occupied by these fish varied little between any sites.
Seasonal variation in microhabitat use is unknown.
REPRODUCTIVE SITE REQUIREMENTS:
Loach minnows spawn in swift, turbulent, shallow riffles and
runs. Spawning occurs in the spring as daytime high water
temperatures reached 15 degrees Celsius. Water is generally clear and
spring runoff declining when spawning occurs. Low turbidity, clean
substrate, and well-aerated water is probably important to successful
spawning. Eggs are adhesive and deposited on the underside of cobble
sized substrate particles, usually 3-5 X 10-18 cm (two dimensions).
Most egg deposition sites are found on smooth, flattened particles;
cobbles of igneous origin that weather to produce a pocked, rounded
surface are not used. Spawning sites are found at a variety of
water depths and velocities, but most are found in water flowing less
than 43 cm/sec and less than 20 cm deep (01,09). Eggs observed on
stones in water flowing less than 15 cm/sec often exhibited heavy
fungal infections (01).
REPRODUCTIVE CHARACTERISTICS:
Gonadal development in female loach minnow begins in early
September as developing ova are evident in Age 0 and Age I fish.
Ovaries develop slowly through the winter and accelerate in March
coincident with increasing water temperature. Eggs in the ovaries
also show the same seasonal pattern of development, but only a
fraction of the total number of eggs in the ovary mature at once,
presumably because of limited space in the body cavity. Ovaries of
reproductively mature loach minnows comprise about 15-30 percent of
body mass. Loach minnows spawn in the spring as water temperatures
Life History - 2 (DRAFT) - Life History
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
reach daytime highs of 15 degrees Celsius. Initiation of spawning
varies across years from March to June and is probably dependant on
water temperature and flow levels. Ripe eggs are dark yellow,
1.3-1.8 mm in diameter, and are laid in clutches of varying size.
Clutches of 100-300 similarly-sized eggs develop at the same time
(01,09), but examination of spawning sites indicates that as few as
four eggs are laid in a single spawning bout. The maximum numbers of
eggs found at a single site was 250, the average was 52, but it is not
known if eggs at spawning site were from a single or multiple spawn or
one or more females (01). Although two age-classes of loach minnows
spawn, Age I fish outnumber Age II fish 4:1 and contribute more to
total reproductive output (01). Fecundity of mature mode eggs is
positively correlated with size and age (01). Females outnumbered
males on nearly all sample dates, usually by a margin of greater than
2:1 (01). Duration of spawning season is four to six weeks.
Fertilized ova held in aquaria all hatched in less than five days.
Actual incubation time is unknown, but 4-7 days is probably a
reasonable estimate based on development intervals of other Gila River
cyprinids (14,22).
PARENTAL CARE:
Male loach minnows are often observed darting away from rocks are
developing ova, but it is not known if adults protect eggs. No care
is given to young.
POPULATION BIOLOGY:
Little is known about the population biology of loach minnow. It
has maintained fairly stable population levels over time at three
sites in the Gila River drainage, New Mexico, and constituted from
about 2.5 to 15 percent of the community in individual samples.
Populations do not exhibit the large fluctuations in distribution or
abundance as have been documented for spikedace (14). Predation by
native fishes on the loach minnow is limited (01,23) because of
non-overlapping uses of habitat. Predation by non-native fishes on
loach minnow has been documented (15,16,17). Food supplies are
probably not limiting in any currently occupied habitat (11,17).
Natural mortlity levels are greatest on newly hatched larvae and
remain high until fish are about 25 mm TL. Mortality is also high on
Age II post-spawning loach minnows. The maximum age for the loach
minnow is about 24 months (01,09). Population fluctuations and
abundance levels of loach minnows are probably controlled by the
amount and quality of available habitat and the frequency of flooding.
SPECIES INTERRELATIONSHIPS:
The reduction in distribution and abundance of the loach minnow
is thought to be a combination of factors including habitat
degradation and interaction with and replacement by non-native fishes
(01,08,10,13). Red shiners (Notropis lutrensis) have been especially
implicated with the decline of the spikedace, and the loach minnow has
probably been affected in a similar manner (02,13). What has not been
adequately demonstrated is whether the reductions in the ranges of
native fishes, like the loach minnow and spikedace, were caused by
prior habitat alterations, or by direct interactions with red shiners.
Life History - 3 (DRAFT) - Life History
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
This pattern of complementary, non-overlapping distribution was
observed in the lower Gila River, New Mexico. Examination of
historical distribution patterns and tracking the progress of invading
red shiners clearly demonstrated that either native fishes never
occupied the area or, more likely, that prior habitat alterations
(flow reductions and subsequent high water temperatures) precluded
native fishes, and that red shiners simply moved into unoccupied
habitat (14,22). In areas of suitable habitat in the Gila River in
the Cliff-Gila Valley, native fishes including loach minnows, remain
common and red shiners very rare (01,14,22).
OTHER LIFE HISTORY DESCRIPTORS:
Loach minnows hatch at 5-6 mm TL (01,09,22), and grow to 30-39 mm
SL by fall. Some variation in growth rates of Age 0 fish was
observed between years and was probably due to time of hatching (01).
Pre-spawning Age I fish averaged 37 mm and Age II fish were 49 mm SL
(01). The largest female loach minnow captured in the Gila River, New
Mexico, was 56 mm SL, the largest male captured was 62 mm SL (01).
Loach minnows do not live more than 24 months (01).
Life History - 4 (DRAFT) - Management Practices
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Controlling/Restricting Off-Road Vehicles
Beneficial Developing/maintaining stream structures
Beneficial Maintaining/Controlling Water Flow
Beneficial Controlling water levels
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Land Acquisition
Beneficial Water Right Acquisition
Beneficial Controlling/Restricting Pesticide Use
Beneficial Controlling/Restricting Herbicide Use
Beneficial Reforestation
Beneficial Restricting Timber Harvest
Beneficial Transplanting wild animals
Beneficial Controlling/Removing Feral Animals
Beneficial Controlling/Removing Domestic Animals
Adverse Off Road Vehicles
Existing Off Road Vehicles
Adverse Climate Alteration
Existing Climate Alteration
Adverse Inherent Reproductive Characteristics
Existing Inherent Reproductive Characteristics
Adverse Predation
Existing Predation
Adverse Underground Mines
Existing Underground Mines
Adverse Surface Mines
Existing Surface Mines
Adverse Soil compaction by heavy equipment in mine areas
Existing Soil compaction by heavy equipment in mine areas
Adverse Siltation
Existing Siltation
Adverse Water Temperature Alteration
Existing Water Temperature Alteration
Adverse Water Level Fluctuation
Existing Water Level Fluctuation
Adverse Groundwater drawdown
Existing Groundwater drawdown
Adverse Irrigating
Existing Irrigating
Adverse Reservoirs
Existing Reservoirs
Adverse Migration barriers
Existing Migration barriers
Adverse Dredging
Existing Dredging
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
Adverse Competition
Existing Competition
Adverse Exotic/Feral/Introducted Species
Management Practices - 1 (DRAFT) - Management Practices
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
RESULT MANAGEMENT PRACTICE
Existing Exotic/Feral/Introducted Species
Adverse Erosion
Existing Erosion
Adverse Grazing
Existing Grazing
Adverse
Existing
Adverse Vegetation Composition Changes
Existing Vegetation Composition Changes
Adverse Forest Alteration
Existing Forest Alteration
Adverse Harvesting
Existing Harvesting
COMMENTS ON MANAGEMENT PRACTICES -
Reasons for the decline of the formerly widespread loach
minnow can be grouped under two general headings. The first, habitat
destruction, is related mostly to incompatable land and water use
practices. Valleys generally surround loach minnow habitat and these
areas were among the first occupied by settlers moving west in the
1800's (08). Water diversion reduced streamflow, water quality, and
increased water temperatures. Livestock grazed in the valley bottoms,
trampled and removed vegetation, and increased erosion and
sedimentation in lotic environments. Large-scale timber removal also
increased erosion, and, in combination with overgrazing and climatic
changes, resulted in changes in the timing and erosive power of runoff
and streamflow. Widespread downcutting of streambeds resulted in deep
arroyos where low gradient, vegetated stream valleys used to exist.
As the Southwest was further settled, high demand for water for
municipal and irrigation purposes resulted in construction of
mainstream dams. These dams radically changed the nature of the lotic
systems by evening out high flow events, lowering average discharge,
and in bottom release dams, lowering water temperature. Ground water
pumping further reduced flows to the point of streambed dessication.
These modifications greatly reduced available habitat for southwestern
fishes, especially the loach minnow. This species is an obligate
riffle dweller and lays its eggs under cobble-sized substrate in
riffles (01,02,09,10) in a fashion similar to many darters in the
genus Etheostoma. Restricted habitats and specialized habits make
loach minnows especially susceptible to dewatering and sedimentation
because these processes affect riffle habitat first and most
adversely. Loach minnows were, however, able to persist beyond the
periods of major physical change in a relatively large portion of
their former range (02,08,11,14).
Importation of non-native species placed a further strain on
loach minnow and other southwestern fish populations through
competitive and/or predatory interactions. Some of these introduced
species, both piscivores and baitfish, were lotic-adapted in their
native ranges and spread quickly through depauperate southwestern
streams (02,12,13). Predation on loach minnow by channel catfish
Management Practices - 2 (DRAFT) - Management Practices
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
(Ictalurus punctatus) (15,16), and rainbow trout (Salmo gairdneri)
(17) has been documented. Minckley and Deacon (13) reported that the
red shiner (Notropis lutensis) was replacing the spikedace throughout
much of its range and surmised that a similar pattern was occurring in
the loach minnow. The long-term consequences of the coexistence of
red shiners and native species including loach minnow is yet
undetermined. Past studies have failed to consider the effects of
habitat changes and its effects on native fish distribution and
abundance, prior to the invasion of red shiners. Interactions
between the loach minnow and red shiner are currently under study by
biologists from Arizona State University.
Future threats to loach minnow include many of the same factors
that precipitated their initial decline. Especially critical to loach
minnow survival is the maintenance of streamflow and natural flow
regimes including occasional flooding. Flooding removes fine
particles from interstitial spaces in riffles and rejuvenates habitat
for loach minnow (01,09). Reservoirs provide a reserve pool of
predator fishes that disperse into loach minnow habitat. Dams
radically alter natural streamflow patterns and construction of these
should be avoided. Further transplantation of additional non-native
species increases the probability of greater predation pressure and
introduction of deleterious diseases.
UNAPPROVED PLAN:
There is no recovery plan for the loach minnow at the current time.
The recovery plan is scheduled for initiation in January of 1988.
Recovery of the loach minnow will include insuring its survival
in its current range and reestablishing the species in areas of
historic occupancy. Perpetuation of the species in the wild depends
on a thorough knowledge of its life history and ecology. Extensive
studies were conducted by New Mexico Game and Fish personnel and
contractors resulting in a detailed status report completed in 1987.
That status report made a series of recommendations that are
summarized herein.
It will be important to develop cooperative agreements among
private landowners, state, Federal agencies, and others as necessary
to protect and enhance the occupied or potential habitat of the loach
minnow in New Mexico and Arizona. The introduction of non-native
warmwater fishes should be discontinued to the Gila drainage. Any
human activities or development which disturb, modify or destroy
occupied or potential loach minnow habitat should be carefully
evaluated. Where and when such activities are determined to be
detrimental to the loach minnow, they should be halted.
Loach minnow studies should continue and be expanded to provide
the information necessary for development and implementation of
appropriate conservation measures. Of particular need are studies to
delineate the effects of human-induced modifications of streams upon
native fish communities. Integral to the above are investigations of
the impacts of introduced fishes on native fish communities. These
studies should be holistic in overall design, yet sufficiently
specific to provide baseline data on all components.
Management Practices - 3 (DRAFT) - Management Practices
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
Areas that should be secured for management to ensure the
survival of the species include, but are not limited to, the Cliff-
Gila Valley, East Fork of the Gila River, the lower Tularosa River,
and the San Francisco River in New Mexico. The feasibility of
reintroductions into areas of historic range should also be evaluated.
Considerations should include habitat suitability and the non-native
predator/competitor load in proposed reintroduction sites. First
phase of reintroduction effort will be the attempted establishment of
the species in suitable habitat. State legislation should be passed
that provides the mechanisms necessary to provide for and maintain
permanent flows in streams for the benefit of fish and wildlife.
Agencies should establish guidelines and an infrastructure to provide
advice and assistance to entities (public and private) that propose
instream or riparian modifications that might damage existing loach
minnow habitat. Loach minnows should be provided the full protection
mandated by Federal, New Mexico, and Arizona laws. This includes
Section 7 Consultation on Federal projects and lands. Finally, public
awareness of the uniqueness of the loach minnow should be increased
through the preparation of information pamplets, interpretive
programs, and use of broadcast and print media.
Management Practices - 4 (DRAFT) - References
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Probst, D.L., K.R. Bestgen, and C.W. Painter. 1987. Distribution,
status, biology, and conservation of the loach minnow, Tiaroga
cobitis, Girard, in New Mexico. Endang. Species Rept. No. 17.
U.S. Fish and Wildl. Serv., Albuquerque, NM.
02 Minckley, W.L. 1973. Fishes of Arizona. Ariz. Game and Fish
Dept., Phoenix, AZ.
03 Minckley, W.L. 1965. Sexual dimorphism in the loach minnow,
Tiaroga cobitis (Cypriniformes). Copeia 1965:380-382.
04 Koster, W.J. 1957. Guide to the fishes of New Mexico. Univ. of
New Mexico Press, Albuquerque, NM.
05 Minckley, W.L. 1980. Tiaroga cobitis Girard, loach minnow.
P. 365 IN, D.S. Lee et al. Atlas of N. Amer. Freshwater Fishes. NC
State Mus. of Nat. Hist., Raleigh.
06 Girard, C. 1856. Researches on the cyprinoid fishes inhabiting
the United States of America, west of the Mississippi Valley, from
specimens in the museum of the Smithsonian Institution. Proceed.
of the Acad. of Nat. Sci. of Philadelphia 8:165-213.
07 Coburn, M. 1986. Pers. comm. Biol. Dept., John Carrol Univ.,
Cleveland, OH.
08 Miller, R.R. 1961. Man and the changing fish fauna of the
American Southwest. Papers of the Mich. Acad. of Sci., Arts, and
Letters 46:365-404.
09 Britt, K.D. 1982. The reproductive biology and aspects of the
life history of Tiaroga cobitis in southwestern New Mexico. MS
thesis. NM State Univ., Las Cruces. 56 pp.
10 Minckley, W.L. 1985. Native fishes and natural aquatic habitats
in U.S. Fish and Wildlife Service Region II west of the Continental
Divide. Rept. to the U.S. Fish and Wildl. Serv., Albuquerque, NM.
Dept. of Zool., Ariz. State Univ., Tempe, AZ. Pp. ix + 158.
11 U.S. Fish and Wildlife Service. 1986. Endangered and threatened
wildlife and plants; determination of the threatened status for the
laoch minnow. Fed. Reg. 51:39468-39478.
12 Hubbs, C.L. 1954. Establishment of a forage fish, the red shiner
(Notropis lutrensis), in the lower Colorado River system. Calif.
Fish and Game 40:287-294.
13 Minckley, W.L., and J.E. Deacon. 1968. Southwestern fishes and
the enigma of "endangered species." Sci. 159:1424-1432.
14 Probst, D.L., K.R. Bestgen, and C.W. Painter. 1986. Distribution,
status, biology, and conservation of the spikedace, Meda fulgida,
in New Mexico. Endang. Species Rept. No. 15, U.S. Fish and Wildl.
Serv., Albuquerque, NM.
15 Montgomery, J.M., Inc. 1985. Wildlife and fishery studies, Upper
Gila Water Supply Project. Part 2: Fisheries. Final Rept. prep.
for U.S. Bur. of Reclamation, Boulder City, NE.
16 Hendrickson, D.A. 1987. Pers. comm. Ariz. Game and Fish Dept.,
Phoenix, AZ.
17 Brooks, J.E. 1987. Pers. comm. U.S. Fish and Wildl. Serv.,
Dexter Natl. Fish Hatchery, Dexter, NM.
18 Barrett, P.J., W.G. Kepner, J.E. Burton, and M.D. Jakle. 1985.
References - 1 (DRAFT) - References
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
Draft Verde Rivdr aquatic study. Joint study; U.S. Fish and Wildl.
Serv., Ariz. Game and Fish Dept., and U.S. Bur. of Reclamation,
May.
19 Brown, D.E. (ed.). 1982. Biotic communities of the American
Southwest: United States and Mexico. Desert Plants 4:1-342.
20 Minckley, W.L. 1981. Ecological studies of Aravaipa Creek,
central Arizona, relative to past, present, and future uses. Final
Rept. for the U.S. Bur. of Land Mgmt. Contract YA-512-CT6-98,
Safford District, Safford, AZ. Ariz. State Univ., Tempe.
21 Schreiber, D.C. and W.L. Minckley. 1982. Feeding interrelations
of native fishes in a Sonoran Desert stream. Great Basin Nat.
41(1981):409-426.
22 Bestgen, K.R. Unpubl. data. Dept. of Biol., Univ. of New Mexico,
Albuquerque, NM.
23 Bestgen, K.R. 1985. Distribution, biology, and status of the
roundtail chub, Gila robusta, in the Gila River drainage, New
Mexico. MS thesis. Colo. State Univ., Fort Collins. 104 pp.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Miller, R.R. and H.E. Winn. 1951. Additions to the known fish
fauna of Mexico: three species and one subspecies from Sonora.
J. of the Wash. Acad. of Sci. 41:83-84.
02 Koster, W.J. 1957. Guide to the fishes of New Mexico. Univ. of
New Mexico Press, Albuquerque, NM.
03 Minckley, W.L. 1973. Fishes of Arizona. Ariz. Game and Fish
Dept., Phoenix, AZ.
04 Minckley, W.L. 1980. Tiaroga cobitis Girard, loach minnow.
p. 365 IN, D.S. Lee et al. Atlas of North American Freshwater
Fishes. North Carolina State Museum of Natural History, Raleigh,
NC.
05 Minckley, W.L. 1985. Native fishes and natural aquatic habitats
in U.S. Fish and Wildlife Service Region II west of the Continental
Divide. Rept. to the U.S. Fish and Wildl. Serv., Albuquerque, NM.
Dept. of Zool., Ariz. State Univ., Tempe, AZ. Pp. ix + 158.
06 Barber, W.E. and W.L. Minckley. 1966. Fishes of Aravaipa Creek,
Graham and Pinal counties, Arizona. The Southwestern Naturalist
11:313-324.
07 Minckley, W.L. 1981. Ecological studies of Aravaipa Creek,
central Arizona, relative to past, present, and future uses. Final
Rept. for the U.S. Bur. of Land Mgmt. Contract YA-512-CT-98,
Safford Dist., Safford, AZ. Ariz. State Univ., Tempe, AZ.
08 Probst, D.L., P.C. Marsh, and W.L. Minckley. 1985. Arizona survey
for spikedace (Meda fulgida) and loach minnow (Tiaroga cobitis):
Fort Apache and San Carlos Indian Reservations and Eagle Creek,
May. U.S. Fish and Wildl. Serv., Albuquerque, NM.
09 Probst, D.L., K.R. Bestgen, and C.W. Painter. 1987. Distribution,
status, biology, and coservation of the loach minnow, Tiarogo
cobitis, Girard, in New Mexico. Endangered Species Rept., No. 17.
U.S. Fish and Wildl. Serv., Albuquerque, NM.
10 Montgomery, J.M. 1985. Wildlife and fishery studies, Upper Gila
Water Supply Project. Part 2: Fisheries. Final Rept. Prepared
References - 2 (DRAFT) - References
Species MINNOW, LOACH
Species Id ESIS252020
Date 14 MAR 96
for U.S. Bur. of Reclamation, Boulder City, NE.
11 Brooks, J.E. 1987. Pers. comm. U.S. Fish and Wildl. Serv.,
Dexter Natl. Fish Hatchery, Dexter, NM.
12 Anderson, R.K. and P.R. Turner. 1977. Stream survey of the San
Francisco River. Final Rept., Contract No. 516-65-24. NM Dept. of
Game and Fish, Santa Fe.
13 Anderson, R.K. 1978. The distribution and aspects of the life
history of Meda fulgida in New Mexico. MS Thesis. New Mexico
State Univ., Las Cruces. 62 pp.
14 U.S. Forest Service. 1979. Habitat study of roundtail chub (Gila
robusta grahami), and loach minnow (Tiaroga cobitis). Gila Natl.
For., Silver City, NM. Contract No. RFQ-R3-6-79-10B, P.O. 43-8399-
9-238.
15 Britt, K.D. 1982. The reproductive biology and aspects of the
life history of Tiaroga cobitis in southwestern New Mexico. MS
thesis. New Mexico State Univ., Las Cruces, NM. 56 pp.
16 Schrieber, D.C. and W.L. Minckley. 1982. Feeding interrelations
of native fishes in a Sonoran Desert stream. Great Basin Nat.
41(1981):409-426.
17 U.S. Fish and Wildlife Service. 1986. Endangered and threatened
wildlife and plants; determination of the threatened status for the
loach minnow. Fed. Reg. 51:39468-39478.
18 Bestgen, K.R. Unpubl. data. Dept. of Biology, Univ. of New Mexico
Albuquerque, NM.
19 Minckley, W.L. and R.W. Clarkson. 1979. Fishes. Pp. 510-531, IN:
W.L. Minckley and M.R. Sommerfeld. Res. Inv. for the Gila River
Complex, Eastern Ariz. Final Rept., Contract YA-512-CT6-216, U.S.
Bur. of Land Mgmt., Safford Dist., Arizona. Ariz. St. Univ.,
Tempe.
References - 3