(DRAFT) - Taxonomy
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
TAXONOMY
NAME - AMPHIPOD, HAY'S SPRING
OTHER COMMON NAMES - AMPHIPOD, HAY'S SPRING; SCUD and HAY'S SPRING
ELEMENT CODE -
CATEGORY - Aquatic Crustaceans
PHYLUM AND SUBPHYLUM - ARTHROPODA,
CLASS AND SUBCLASS - CRUSTACEA,
ORDER AND SUBORDER - AMPHIPODA,
FAMILY AND SUBFAMILY - CRANGONYCTIDAE,
GENUS AND SUBGENUS - STYGOBROMUS,
SPECIES AND SSP - HAYI,
SCIENTIFIC NAME - STYGOBROMUS HAYI
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Hay's Spring Amphipod
Stygobromus hayi (Hubricht and Mackin, 1940)
KINGDOM: Animal GROUP: Crustacean
PHYLUM: Arthropoda CLASS: Crustacea
ORDER: Amphipoda FAMILY: Crangonyctidae
Stygobromus hayi (Hay's Spring amphipod) is an eyeless,
unpigmented gammaridean amphipod crustacean of typical crangonyctid
facies (01,02). The third uropod is greatly reduced, lateral sternal
gills are bifurcate and the uronites are fused (02). The largest
known females measure approximately 10 mm; largest males are 9.75 mm.
When first described, this species was placed in the genus
Synpleonia by Hubricht and Mackin (09). It was later erroneously
listed from two caves in Pennsylvania by Hubricht (02,07). In 1959,
Hubricht synonymized this species with Synpleonia tenuis (02,08). It
was resurrected from synonymy and redescribed by Holsinger in 1967 and
assigned to the genus Stygonectes (02). Later, it was transferred to
the genus Stygobromus by Holsinger (03).
A series of ten cotypes (syntypes) are deposited in the National
Museum of Natural History of the Smithsonian Institution under catalog
numbers of the United States National Museum (USNM 77804). Additional
Taxonomy - 1 (DRAFT) - Taxonomy
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
paratypes are also in the Smithsonian collections. Six topotypes,
collected 7 April 1978, are in the collection of J.R. Holsinger at Old
Dominion University (H-1886). Other topotypes presumably collected by
Drs. J.L. Barnard and G.S. Karaman are also probably in the
Smithsonian collections.
Another common name for this species is Hay's Spring scud (05,06,
10).
Taxonomy - 2 (DRAFT) - Status
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
STATUS
Coded Status
E: Federal Endangered
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
Hay's Spring amphipod (Stygobromus hayi) 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
District of Columbia.
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: District of Columbia
DESIGNATED STATUS: None
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
None.
ECONOMIC STATUSES:
None.
Status - 1 (DRAFT) - Status
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
77/01/12:42 FR 02507/02515 - Proposal to list as Endangered
79/12/10:44 FR 70796/70797 - Proposal withdrawn
80/07/25:45 FR 49850/49851 - Reproposal to list as Endangered
82/02/05:47 FR 05425/05427 - Final rule, list as Endangered
87/07/07:52 FR 25523/25528 - Notice of five year review
Status - 2 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
INLAND AQUATIC
LAND USE -
Commercial and Services
Transportation, communications, and Util
Mixed Urban or Built-up Land
Deciduous Forest Land
Streams and Canals
COMMENTS ON HABITAT ASSOCIATIONS -
The habitat of Stygobromus hayi (Hay's Spring amphipod) consists
of a small spring, possibly permanent but seep-like in appearance
within a densely populated urban area, the National Zoological
Park, Washington, D.C.. A short section of the spring runs
immediately in front of the resurgence itself (04). The spring
appears to issue forth from crevices in Precambrian rocks of the
Piedmont province (02). The amphipods occur in decaying deciduous
leaf litter and mud at the spring exit. They are associated with
epigean amphipods, Crangonyx (near pseudogracilis), asellid isopods,
Caecidotea kenki, and oligochaetes. Crangonyx and Caecidotea were
much more common when observed by Holsinger on 7 April 1978 (04). The
original collection of S. hayi by Leslie Hubricht in March 1938
contained a single, small specimen of another stygobiont amphipod,
Stygobromus tenuis, a species common to groundwater outlets throughout
much of the greater Washington, D.C. area (02,03). Stygobromus tenuis
was not found here by sampling in April 1978 (04).
High flood levels from Rock Creek may adversely affect the spring
habitat by removing individual amphipods as well as the leaves and
soft bottom sediments that form their microhabitat (11).
The spring water is cool and of typical groundwater temperature
for this region (ca. 10-13 deg. C), fresh, and not obviously polluted.
Other physical/chemical parameters have not been measured (04). Most
of the surrounding surface vegetation consists of a variety of
deciduous trees and various small plants (04).
It should be noted that only a small percentage of the actual
population of this species is probably seen in the spring habitat
itself (04). Given that S. hayi is of stygobiont facies (i.e.,
eyeless and unpigmented), it probably inhabits cracks, crevices and
interstitial spaces of the mantle/bedrock area that forms the recharge
zone for the spring (02). The full range of this species may extend
to the limits of this groundwater aquifer, but the extent of the
aquifer is unknown (04).
Habitat Associations - 1 (DRAFT) - Food Habits
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
FOOD HABITS
TROPHIC LEVEL -
HERBIVORE
LIFESTAGE FOOD FOOD PART
General Detritus
General Bacteria
General Myxomycophyta
General Deciduous Trees-Leaves/Twigs
Food Habits - 1 (DRAFT) - Environment Associations
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
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: Springs [flowing]
Environment Associations - 1 (DRAFT) - Life History
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
LIFE HISTORY
FOOD HABITS:
Nothing definitive is currently known about the food requirements
or preferences of Stygobromus hayi (Hay's Spring amphipod).
Considering its association with decaying deciduous leaves and
organically enriched mud, it is assumed that S. hayi feeds on leaves,
decaying organic detritus, and decomposer microorganisms (e.g.,
bacteria and fungi) which occur on the organic material (04). Most
freshwater amphipods are believed to be primarily herbivores, and
there is no evidence to the contrary for S. hayi (04).
HOME RANGE/TERRITORY:
This is not applicable to S. hayi (04).
PERIODICITY:
No periodicity has been observed for S. hayi (04).
MIGRATION PATTERNS:
Stygobromus hayi is nonmigratory (04).
COVER/SHELTER REQUIREMENTS:
Stygobromus hayi is found in a type of groundwater habitat called
the hypotelminorheic, which can be defined as the outflow of a small
spring or seep through fine sediments or leaf litter (03,04). Wet mud
and decaying leaves offer cover and shelter necessary for the survival
of this species in the habitat where it is found (04). However,
probably a much greater number of animals live in the subterranean
groundwater aquifer that feeds the spring but which is inaccessible to
direct observation (04). This conjectured subterranean habitat
probably consists of cracks, crevices and interstitial spaces
saturated with groundwater (02,03). Therefore, the watershed behind
the spring must be protected in order to insure continued survival of
this species (04).
REPRODUCTIVE SITE REQUIREMENTS:
It is assumed that the present spring habitat and the associated
groundwater aquifer provide the reproductive site requirements for
this species (04).
REPRODUCTIVE CHARACTERISTICS:
Nothing definitive is currently known about breeding or
reproduction in this species (02,03,04). Of the 27 or 28 specimens
examined by Holsinger, approximately 12 were females, 12 were males,
and three were juveniles (04). Females brooding eggs or embryos have
not been observed to date, although a single female, 8.75-9.0 mm long,
from a collection made by Leslie Hubricht on 9 March 1938, had setose
brood plates. Presumably, females are sexually mature at this size,
because setose brood plates (oostegites) form the brood pouch for eggs
following fertilization. Juveniles were present in the 9 March 1938
and 7 April 1978 samples, but whether they occur in seasons other than
spring is unknown (samples have been taken only in March and April)
(04).
Life History - 1 (DRAFT) - Life History
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
PARENTAL CARE:
No data are available on parental care, although like all other
amphipods, S. hayi females undoubtedly brood their eggs in pouches
formed from oostegites on the ventral side (04).
POPULATION BIOLOGY:
Because of very limited sampling and the small accessible
population, there are no data available on population biology of this
species (02,03,04).
SPECIES INTERRELATIONSHIPS:
No information is available.
OTHER LIFE HISTORY DESCRIPTORS:
No information is available.
Life History - 2 (DRAFT) - Management Practices
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Restricting/regulating human disturbance of populations
Beneficial Maintaining/Controlling Water Flow
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Controlling/Restricting Pesticide Use
Adverse Collecting
Existing Collecting
Adverse Recreational development
Existing Recreational development
Adverse Soil compaction by heavy equipment in mine areas
Existing Soil compaction by heavy equipment in mine areas
Adverse Siltation
Existing Siltation
Adverse Draining wetlands, marshes, ponds, lakes
Existing Draining wetlands, marshes, ponds, lakes
Adverse Flooding
Existing Flooding
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
COMMENTS ON MANAGEMENT PRACTICES -
Reasons for the current Endangered status of Stygobromus hayi
(Hay's Spring amphipod) are given as follows:
1) Vulnerability to extinction by its extremely restricted
distribution.
2) Proximity of its habitat (a single spring) to an area used in the
past (before 1982) for the disposal of fill from construction
activities in the National Zoological Park.
3) Accidential destruction of the spring habitat during material
disposal or other operations on an adjacent area just south of the
South Gate to the park.
4) Overcollecting.
5) High flood levels from Rock Creek may adversely affect the spring
habitat by removing individual amphipods as well as the leaves and
soft bottom sediments that form their microhabitat.
There is also a possibility that Rock Creek will become polluted
with sewage effluent and overflow onto the spring during a major flood
(04). Surrounding urban and commercial areas that include highways,
utilities, etc. pose a current threat to this species. A potential
future threat may also be from urban runoff threatening the water
quality within the aquifer.
Officials of the National Zoological Park have a Memorandum of
Understanding with the Fish and Wildlife Service that addresses
concerns 1 through 4 above. They have agreed to perform all things
necessary for or incidental to the protection of S. Hayi. A copy of
the MOU is on file with the Fish and Wildlife Service and the National
Zoo.
Management Practices - 1 (DRAFT) - Management Practices
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
The status of proposals in 1978 for discharge of treated sewage
into Rock Creek by the Washington Suburban Sanitary Commission, and
similar discharge into the Creek by a sewage treatment plant upstream
in Montgomery County, Maryland (see 05,06) are unknown.
UNAPPROVED PLAN:
No recovery plan or target date has yet been set for initiation
of a formal recovery plan. A Memorandum of Understanding has been
entered into by the National Zoological Park and the U.S. Fish and
Wildlife Service to implement recovery actions for the Hay's Spring
amphipod (Stygobromus hayi).
Recommended recovery actions include: protection of the
only known habitat site (on National Zoological Park property)
by limiting human access and insuring that park maintenance or other
activities do not disturb the species' habitat (e.g., pesticide
spraying or development of the spring habitat); and monitoring of
water quality in the spring occupied by the amphipod.
Ongoing and completed recovery actions include: fencing and
gating by the Smithsonian Institution (National Zoological Park) to
prevent human access; and periodic monitoring of the habitat to insure
that it remains undisturbed.
Management Practices - 2 (DRAFT) - References
Species AMPHIPOD, HAY'S SPRING
Species Id ESIS455001
Date 13 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Garrison, B. 1981. Our very own endangered species. Washington
Post Magazine, Feb. 8, 1981. Pages 14-16.
02 Holsinger, J.R. 1967. Systematics, speciation and distribution of
the subterranean amphipod genus Stygonectes (Gammaridae). U.S.
Natl. Mus. Bull. 259:1-176.
03 Holsinger, J.R. 1978. Systematics of the subterranean amphipod
genus Stygobromus (Crangonyctidae). Part II: Species of the
eastern United States. Smithsonian Contrib. Zool. 266:1-144.
04 Holsinger, J.R. 1985. Data in research files. Dept. Biol. Sci.,
Old Dominion Univ., Norfolk, VA 23508.
05 Holt, B. 1978. Hay's Spring scud vs. sewage plan. Washington
Star, 6 May 1978. Pages A-1,A-6.
06 Holt, B. 1978. Hay's spring scud are headed for endangered
species list. The Washington Star, 16 May 1978. Pages B-1,B-2.
07 Hubricht, Leslie. 1943. Studies on the Nearctic freshwater
Amphipoda, III: Notes on the freshwater Amphipoda of eastern
United States with description of ten new species. Am. Mid. Nat.
29:683-712.
08 Hubricht, L. 1959. Malacostraca (Amphipoda). Pages 876-878. IN:
Freshwater biology (2nd. Ed.). W.T. Edmondson, ed. Wiley & Sons,
Inc., New York.
09 Hubricht, L. and J.G. Mackin. 1940. Description of nine new
species of fresh-water amphipoda crustaceans with notes and new
localities for other species. Am. Mid. Nat. 23:187-218.
10 Jacobs, Madeleine. 1982. Scud officially `endangered'. The Torch
No. 82 (4 April 1982). Pages 1,4.
11 USFWS. Febuary 5, 1982. Endangered and threatened wildlife and
plants; LIsting Hay's Springs amphipods as an Endangered species.
FEd. Reg. 47(25):5425-5426.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Holsinger, J.R. 1967. Systematics, speciation and distribution of
the subterranean amphipod genus Stygonectes (Gammaridae). U.S.
Natl. Mus. Bull. 259:1-176.
02 Holsinger, J.R. 1978. Systematics of the subterranean amphipod
genus Stygobromus (Crangonyctidae). Part II: Species of the
eastern United States. Smithsonian Contrib. Zool. 266:1-144.
03 Holsinger, J.R. 1985. Data in research files. Department of
Biological Sciences, Old Dominion University, Norfolk, VA 23508.
References - 1