(DRAFT) - Taxonomy
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
TAXONOMY
NAME - DARTER, WATERCRESS
OTHER COMMON NAMES - DARTER and WATERCRESS
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - OSTEICHTHYES,
ORDER AND SUBORDER - PERCIFORMES,
FAMILY AND SUBFAMILY - PERCIDAE,
GENUS AND SUBGENUS - ETHEOSTOMA,
SPECIES AND SSP - NUCHALE,
SCIENTIFIC NAME - ETHEOSTOMA NUCHALE
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Watercress Darter
Etheostoma nuchale Howell and Caldwell, 1965
KINGDOM: Animal GROUP: Fish
PHYLUM: Chordata CLASS: Osteichthyes
ORDER: Perciformes FAMILY: Percidae
The watercress darter, Etheostoma nuchale, was first described by
Howell and Caldwell in 1965 (01). It is a rather small (maximum
SL=45 mm), robust darter of the subgenus Oligocephalus. It has a well
developed frenum and a distinctly humped nape. The nape is naked
medially, as are the head, breast, and prepectoral areas. The cheeks
are largely naked with a few exposed or embedded scales along the
posterior ventral margin of the eye while the opercle is scaled. The
lateral line is moderately straight and incomplete. Total scales in
the lateral line range from 35-42 (X=37) with 12-24 pored scales
(X=17) and 15-27 unpored scales (X=20). The supratemporal and usually
the infraorbital canals are incomplete and the branchiostegal
membranes are moderately to narrowly conjoined. The spine and fin ray
counts are as follows: dorsal VIII - IX (usually IX or X), 10-12;
anal II (occasionally III), 6-8; pectoral (total of both sides) 22-24.
Watercress darters are sexually dimorphic in color. The dorsum
Taxonomy - 1 (DRAFT) - Taxonomy
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
and sides of both sexes are mottled with brown and black pigment
which, in the female, may form vertical bands on the posterior part of
the body. These bands are best developed ventrally. In males the
bands are blue or bluish alternating with poorly defined red or orange
bars. The breast and belly are white or yellowish white in females
and bright red or reddish orange in males.
Four to nine dorsal saddles may be present and most individuals
have a median light stripe on the nape. There are three vertically
aligned black spots at the base of the caudal fin. In males these are
followed by two yellow to orange basicaudal spots.
The spiny dorsal fin has an outer margin of blue followed by
bands of red, blue, and red. This pattern is well developed in
breeding males, faint in females. The soft dorsal fin of males
displays the same pattern, while the anal, basal portion of the
caudal, and the paired fins are blue. In females, the soft dorsal,
anal, caudal, and paired fins are speckled with small brown spots.
Keys and/or descriptions useful in identifying the fish are found
in: 01,02,03,04,05,06, and 07.
Taxonomy - 2 (DRAFT) - Status
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
STATUS
Coded Status
Alabama; Federal Endangered
Alabama; State Listed
Alabama; Unofficially Listed
E: Federal Endangered
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The watercress darter (Etheostoma nuchale) 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 Alabama.
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
(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: Alabama
DESIGNATED STATUS: Nongame Wildlife Species
ADMINISTRATIVE AGENCY: Div. of Game and Fish
STATE STATUTE: Game and Fish Reg. 87-GF-7.
Status - 1 (DRAFT) - Status
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
UNOFFICIAL LIST: Endangered, In: Mount, R.H. 1986. Vertebrate
Animals of Alabama in Need of Special
Attention. Ala. Agri. Expt. Sta., Auburn Univ.
124 pp.
Endangered, In: Endangered and Threatened
Plants and Animals of Alabama. Ala. Museum of
Natural History, Bulletin No. 2.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
Listed in IUCN Red Data Book for Pices (1977). This species is
also listed by the Convention on Nature Protection and Wildlife
Preservation in the Western Hemisphere, 1970.
ECONOMIC STATUSES:
The watercress darter serves as a unique source of genetic
material, as a biological indicator, and it enhances the diversity of
the ecosystem in which it occurs.
70/08/25:35 FR 13519/ - Proposed Rule, listing as Endangered
70/10/13:35 FR 16047/16048 - Final Rule, listing as Endangered
75/05/16:40 FR 21499/21501 - Notice of intent, Critical Habitat
85/07/22:50 FR 29901/29909 - Five year review
Status - 2 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
INLAND AQUATIC
LAND USE -
Residential
Commercial and Services
Transportation, communications, and Util
Streams and Canals
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Riverine, upper perennial UB1
Riverine, lower perennial UB1
Riverine, upper perennial AB3
Riverine, upper perennial AB2
Riverine, upper perennial AB1
Riverine, lower perennial AB3
Riverine, lower perennial AB2
Riverine, lower perennial AB1
Palustrine EM1
Palustrine AB5
COMMENTS ON HABITAT ASSOCIATIONS -
The watercress darter, Etheostoma nuchale, is only found in
spring basins, spring fed ponds, and the runs and creeks issuing from
them (03,04,06,08,09). These springs and runs have bottoms of chert
gravel in the areas of swifter current and silt in the areas of little
current (08).
Water temperature usually remains between 16 and 18 degrees C
year round. The temperature preference and limits of this species are
unknown, but it is likely that it prefers water that does not vary
much from the 16-18 degree range of its spring habitat (10,11).
Howell (01,08) notes that within the springs the darters are
usually more abundant in areas of slow moving current with heavy
growths of aquatic vegetation. At Glenn Spring the predominate
vegetation is watercress, Nasturtiun, which fills backwater areas and
lines the spring run. Rocks in the small spring basin are covered
with unidentified aquatic moss and the lower portion of the spring run
has a substantial growth of cattail, Typha. Thomas Spring lacks
watercress. The dominate submerged vegetation here is Chara with some
cattail lining a few areas of the shore. The spring pond also has
heavy floating mats of Spirogyra, particularly in the summer months
(08,11).
Roebuck Spring has heavy mats of moss (Fissidens and
Drepanocladus) covering rocks in the upper portion of the spring
basin. The center of the basin is dominated by a stand of Potamogeton
with floating clumps of Spirogyra. The spring creek contains stands
of cattail, Ceratophyllum; bur reed, Sparganium; some Ludwigia; and
cattail, Typha (11).
The watercress darter is apparently dependent upon the presence
of submerged aquatic vegetation for shelter from predators and egg
deposition sites (11), and probably as a source of food items (such as
aquatic insects and snails). Other environmental requirements of the
watercress darter are unknown.
Each of the springs where the watercress darters occur are
adjacent to urbanized areas such as highways and residential
Habitat Associations - 1 developments, and could be adversely affected by activities in these
areas.
Habitat Associations - 2 (DRAFT) - Food Habits
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
LIFESTAGE FOOD FOOD PART
General Zooplankton
General Arthropods
General Crustaceans
General Molluscs
Food Habits - 1 (DRAFT) - Environment Associations
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 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 DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
LIFE HISTORY
FOOD HABITS:
Almost no information is available regarding the food habits of
the watercress darter, Etheostoma nuchale. No stomach content
analyses have been performed; however, Howell (10), examining x-rays
of specimens for taxonomic purposes, noted the presence of small
aquatic snails in their stomachs. Since almost all darters for which
diets are known utilize aquatic insects and microcrustaceans (06), it
is highly likely that they also comprise part of the diet of the
watercress darter. Platania (12) reports that prey species include
snails, crustaceans, and insect larvae.
HOME RANGE/TERRITORY:
Male watercress darters have been observed engaged in agonistic
bouts and it is likely that they, at least, maintain either an
individual space or a moving territory. Beyond that, nothing is known
regarding territorial behavior or home range (11).
PERIODICITY:
The overwhelming majority of darters are diurnal (06) and
observations indicate that the watercress darter is also (11).
MIGRATION PATTERNS:
Non-migratory (11).
COVER/SHELTER REQUIREMENTS:
The watercress darter, is dependent upon the presence of
submerged aquatic vegetation for cover from predators, as a site for
egg deposition (11), and as a source of aquatic insects and snails
upon which the darter apparently feeds (08). There is no information
available on the species of plants preferred as egg deposition sites
(11).
Destruction of aquatic vegetation by introduced grass carp,
Ctenopharyngodon idella, almost eradicated the Thomas Spring
population (09,10,11). Recovery followed only with removal of the
carp and reestablishment of the submerged vegetation (10,11).
REPRODUCTIVE SITE REQUIREMENTS:
The watercress darter lays its eggs on submerged aquatic
vegetation in the springs and runs in which it lives (11). At Roebuck
Spring darters have been observed laying their eggs in mats of aquatic
moss (Fissidens and Drepanocladus) (11). Moss is limited at Glenn
Spring and missing at Thomas Spring; thus, the darters must also use
other types of vegetation for egg deposition; however, it is not known
which plants they prefer. Also unknown are any preferences of depth,
current, water temperature, and pH.
REPRODUCTIVE CHARACTERISTICS:
Only a limited amount of information is currently available on
the reproductive behavior of the watercress darter. Observations show
that during the reproductive season males will attempt to court any
female they observe. Females not ready to spawn simply flee at the
Life History - 1 (DRAFT) - Life History
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
approach of a male (11).
Courtship consists of the male closely following the female.
When she stops he may rest his head against her nape or back, rest his
body against hers, or display his fins. Any male observing the pair
will attempt to displace the courting male. The largest male usually
wins. Spawning females will accept any male who can displace the
other males.
Females select the spawning site which is off the bottom in
submerged aquatic vegetation. The number of eggs layed per spawning
and the number of times a female spawns per season are unknown. the
extent of the breeding season is also unclear. Howell and Caldwell
(01) found gravid females from March to July in samples from Glenn
Spring. Observations by Stiles (11) at Roebuck Spring tend to support
a mid-May to early July spawning period.
PARENTAL CARE:
Eggs are deserted at the completion of the spawning act and no
parental care is given (11).
POPULATION BIOLOGY:
Little is known concerning the population biology of the
watercress darter. One major limiting factor is the availability of
submerged aquatic vegetation in the springs inhabited by the fish (09,
10,11). As mentioned in preceding sections, this vegetation is
necessary for cover, feeding, and reproduction. Other limiting
factors are uncertain. Howell (08) has theorized that the failure of
a 1965 transplant into Prince Spring may have been due to competition
with the redfin darter, Etheostoma whipplei. Other potential
competitors and predators are unknown. No information is available on
survival and mortality rates, sex ratio, longevity, rate of increase,
etc.
Current management plans center on protecting and expanding the
existing populations. Increase in habitat by construction of a second
pond at Thomas Spring and a low level dam in the spring creek at
Roebuck Spring has resulted in an apparent increase in those
populations (10), but a reduction in the outflow from Glenn Spring is
resulting in a decrease in that population (10).
Future plans may include transplants into other springs in the
upper Warrior basin if sufficient life history data becomes available
and existing populations build up to level that can support transplant
efforts.
SPECIES INTERRELATIONSHIPS:
Introduction of herbivorous fishes, particularly the grass carp,
Ctenopharyngodon idella, into the watercress darter's spring habitat
poses a serious threat to the fish (09,10,11).
OTHER LIFE HISTORY DESCRIPTORS:
None.
Life History - 2 (DRAFT) - Management Practices
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Developing/maintaining stream structures
Beneficial Maintaining/Controlling Water Flow
Beneficial Developing/maintaining/protecting wetlands
Beneficial Controlling water levels
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Land Acquisition
Beneficial Creating Artificial Habitat/Nesting Structure
Beneficial Reforestation
Beneficial Controlling/Removing Exotic Vertebrates
Adverse Highway/Railroads
Existing Highway/Railroads
Adverse Soil compaction by heavy equipment in mine areas
Existing Soil compaction by heavy equipment in mine areas
Adverse Siltation
Existing Siltation
Adverse Groundwater drawdown
Existing Groundwater drawdown
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
Adverse Exotic/Feral/Introducted Species
Existing Exotic/Feral/Introducted Species
Adverse Erosion
Existing Erosion
COMMENTS ON MANAGEMENT PRACTICES -
The watercress darter, Etheostoma nuchale, is known from only
three springs in Jefferson County, AL. Glenn Spring, the type
locality (01), has shown wide fluctuations in flow (01,08,08) and
there is fear that recharge of the spring is being adversely affected
by increasing urban development. This spring is also situated next to
heavily used county highway 20 and widening of this highway or an
accidental toxic spill could destroy this population. Finally, the
lower portion of the spring run shows increased eutrophication and is
in danger of being choked by an overabundance of aquatic plants (08).
Thomas Spring, on the Watercress Darter National Wildlife Refuge,
was severely impacted by the 1976 introduction of the grass carp,
Ctenopharyngodon idella, which destroyed vegetation the darter is
dependent upon (09). The population is just now recovering following
removal of the grass carp, reestablishment of the spring's aquatic
vegetation, and the transplanting of 100 individuals from Glenn spring
in April of 1981.
Roebuck Spring, the third locality, is situated in an area of
rapid urban development. Recently the State has expressed an interest
in selling a tract of land just above the spring to private
developers. Development close to the spring poses serious threats
from construction runoff and disruption or contamination of the
aquifer. In addition, both Roebuck and Glenn Springs have shown high
coliform counts (08,09) indicating probable contamination by organic
Management Practices - 1 (DRAFT) - Management Practices
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
pollution, possibly from septic tanks. Bacterial contamination has
been pointed to (08) as a possible cause for the high incidence of gas
bubble disease which often occurs in the Roebuck Spring population;
however, supersaturation by nitrogen may be responsible.
In assessing future threats to the species, the increase in urban
development in this area of Jefferson County would appear to pose the
most serious danger. This development is most likely to effect the
species through disruption or pollution of the aquifers that the
springs are dependent upon. Glenn Spring is also threatened by its
proximity to a busy highway with its ever present danger of toxic
spills.
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1984. Revised Recovery Plan for the
Watercress Darter, Etheostoma nuchale. U.S. Fish and Wildlife
Service, Atlanta, GA. 31 pp.
Actions for the recovery of the watercress darter, Etheostoma
nuchale, include:
1) Obtain long-term authority to manage and protect Glenn Spring and
Roebuck Spring through land agreements, easements, acquisition, and/or
maintaining a good working relationship with current land owners.
2) Conduct habitat enhancement projects at Glenn Spring and Thomas
Spring, including creation of artificial habitat with low level dams,
habitat revegetation, and modification of the stream banks.
3) Monitor habitats and populations.
4) Transplant watercress darters to other suitable habitats.
5) Control/Remove exotic species detrimental to this darter such as
grass carp, Ctenopharyngodon idella.
Current ongoing recovery activities include the recent
construction of a second pond habitat at Thomas Spring (now the
Watercress Darter National Wildlife Refuge), construction of three low
level stone dams at Glenn Spring and monitoring of watercress darter
population trends (scheduled to begin spring and summer 1985).
Management Practices - 2 (DRAFT) - References
Species DARTER, WATERCRESS
Species Id ESIS254011
Date 13 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Howell, W.M. and R.D. Caldwell. 1965. Etheostoma (Oligocephalus)
nuchale, a new darter from a limestone spring in Alabama. Tulane
Stud. Zool. 12(4):101-108.
02 Eddy, S. and J.C. Underhill. 1978. How to Known the Freshwater
Fishes. 3rd ed. Wm. C. Brown Co., Dubuque. 215 pp.
03 Kuehne, R.A. and R.W. Barbour. 1983. The American Darters. Univ.
Kentucky Press, Lexington, Ky. 177 pp.
04 Mettee, M.F. 1978. The fishes of the Birmingham-Jefferson County
region of Alabama with ecologic and taxonomic notes. Geol. Surv.
Ala. Bull. 115. 182 pp.
05 Moore, G.A. 1968. Fishes. Pages 21-165. IN: W.F. Blair, et.
al. Vertebrates of the United States. 2nd ed. McGraw-Hill Book
Co., New York.
06 Page, L.M. 1983. Handbook of Darters. T.F.H. Pub., Neptune City,
NJ. 271 pp.
07 Smith-Vaniz, W.F. 1968. Freshwater Fishes of Alabama. Auburn
Univ. Agr. Exp. Sta. 211 pp.
08 U.S. Fish and Wildlife Service. 1984. Revised Watercress Darter
Recovery Plan. U.S. Fish and Wildlife Service. 31 pp.
09 Ono, R.D., J.D. Williams, and A. Wagner. 1983. Vanishing Fishes
of North America. Stone Wall Press, Inc., Washington, D.C. 257pp.
10 Howell, W.M. January 1986. Personal communication. Biology
Department, Samford University, Birmingham, AL 35229.
11 Stiles, R.A. Personal observations. Biology Department, Samford
University, Birmingham, AL 35229.
12 Platania, S.P. 1980. Etheostoma nuchale. IN: Lee, et al., Atlas
of North American Freshwater Fish. N. Carol. State Mus., Raleigh.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Howell, W.M. and R.D. Caldwell. 1965. Etheostoma (Oligocephalus)
nuchale, a new darter from a limestone spring in Alabama. Tulane
Stud. Zool. 12(4):101-108.
02 Howell, W.M. and A. Black. 1976. Status of the watercress darter.
Proc. Southeast. Fish. Counc. 1(3):1-3.
03 Howell, W.M. January 1986. Personal communication. Biology
Department, Samford University, Birmingham, AL 35229.
04 U.S. Fish and Wildlife Service. 1984. Revised Watercress Darter
Recovery Plan. U.S. Fish and Wildlife Service. 31 pp.
References - 1