(DRAFT) - Taxonomy
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
TAXONOMY
NAME - RAIL, CLAPPER, YUMA
OTHER COMMON NAMES - RAIL, CLAPPER, YUMA;RAIL, CLAPPER; HEN, MARSH, SALT-WATER; HEN and MARSH; PALMOTEADOR
ELEMENT CODE -
CATEGORY - Birds
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - AVES,
ORDER AND SUBORDER - GRUIFORMES,
FAMILY AND SUBFAMILY - RALLIDAE,
GENUS AND SUBGENUS - RALLUS,
SPECIES AND SSP - LONGIROSTRIS, YUMANENSIS
SCIENTIFIC NAME - RALLUS LONGIROSTRIS YUMANENSIS
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Yuma Clapper Rail
Rallus longirostris yumanensis Dickey, 1923
KINGDOM: Animal GROUP: Bird
PHYLUM: Chordata CLASS: Aves
ORDER: Gruiformes FAMILY: Rallidae
The clapper rail (Rallus longirostris Boddaert) is a polytypic
species characterized by having a long, slightly down-curved bill.
Like most rails, this species has a short tail, medium-length legs,
and short, rounded wings. The primarily gray-plumaged clapper rail is
most similar to the closely related redder-plumaged king rail (Rallus
elegans). Occasionally king rail - clapper rail hybrids occur in the
eastern United States. The king rail is primarily an inland fresh-
water marsh species confined to the eastern half of the continental
U.S. The king rail does enter brackish and salt-water marshes where
its distribution overlaps that of the clapper rail. In the East, the
clapper rail is primarily a coastal salt-water marsh species. The two
species interbreed in some areas of sympatry but not in others (02).
This hybridization has caused some biologists to conclude that they
should be considered conspecific, whereas other researchers maintain
that genetic isolation and the zones of introgression are adequate to
Taxonomy - 1 (DRAFT) - Taxonomy
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
retain species specific distribution. At present, the two forms are
considered separate species even though they interbreed in very
limited areas and produce viable hybrids (03).
The Yuma clapper rail, Rallus longirostris yumanensis Dickey
(01), population is distinct from most other clapper rail populations
morphologically by having a brighter orange-plumage, and ecologically
by largely occurring in fresh-water (like the king rail), at least for
breeding. R.l. yumanensis is unique among the Western and most
Eastern populations of the clapper rail by being partly migratory.
In fact, some authors consider this population to be a subspecies of
the king rail; however, acceptance of this has not gained momentum
(03). The first specimens of yumanensis collected in the U.S. were
taken in 1921 by Huey and Canfield (01) in the vicinity of Laguana Dam
(16 km north of Yuma, Yuma County, AZ). The original description of
the type specimen is found in Dickey (01). General descriptions are
found in Bent (04). The history of known occurrence for R.l.
yumanensis in the U.S. is summarized by Ohmart and Smith (05). Other
common names of clapper rails include marsh hen, salt-water marsh
hen, and in Mexico the "palmoteador".
Taxonomy - 2 (DRAFT) - Status
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
STATUS
Coded Status
E: Federal Endangered
Federal Migratory
Non-consumptive recreational
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Yuma clapper rail (Rallus longirostris yumanensis) 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 subspecies has this status wherever found
including Mexico and the States of Arizona, California, and Nevada.
This subspecies 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.
The species (Rallus longirostris) is protected by the Migratory
Bird Treaty Act (16 U.S.C. 703-711 et seq.; 50 CFR 10.13).
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.
Status - 1 (DRAFT) - Status
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
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.
BR -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control. Also responsible
for cooperating in the management/recovery on Bureau
of Reclamation lands.
COE -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 and water management on
land involving Federal funding for projects.
DOD -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control. Also responsible for
management/recovery on Department of Defense lands.
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 Endangered
ADMINISTRATIVE AGENCY: Arizona Game and Fish Commission
Status - 2 (DRAFT) - Status
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
STATE STATUTE: Arizona Revised Statutes 17-102
STATE: California
DESIGNATED STATUS: Rare
ADMINISTRATIVE AGENCY: California Department of Fish and
Game
STATE STATUTE: California Administrative Code, Title 14,
Section 670.5
STATE: Neveda
DESIGNATED STATUS: Recognized Endangered
ADMINISTRATIVE AGENCY: Neveda Division of Enforcement
STATE STATUTE: Neveda Administrative Code, Sec 503.015 to
503.080, December 21, 1981
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
Rallus longirostris (the Palmoteador) is listed in Mexico's
"Especies de Fauna en Peligro de Extincion en Mexico"; a
recommendation to CITES I (Reyes; August 1982). This species is also
listed by the Convention on Nature Protection and Wildlife
Preservation in the Western Hemisphere, 1970.
ECONOMIC STATUSES:
Some members of the family Rallidae are legally hunted in the
United States, though Yuma clapper rails have never been legally
hunted in Arizona or California. This species has value as a
component of Arizona and California's natural heritage of biotic
diversity.
67/03/11:35 FR 04001/ - Listed as Endangered
79/05/21:44 FR 29565/29577 - Five year review
85/04/05:50 FR 13707/13722 - Revised list of Migratory Birds
85/07/22:50 FR 29901/29909 - Five year review
Status - 3 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
TERRESTRIAL
INLAND AQUATIC
COASTAL
LAND USE -
Industrial
Mixed Urban or Built-up Land
Cropland and Pasture
Orchards, Groves, Vineyards, Nurseries,
Shrub and Brush Rangeland
Streams and Canals
Lakes
Reservoirs
Bays and Estuaries
Nonforested Wetland
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Riverine, lower perennial BB2
Palustrine EM1
Palustrine EM
Estuarine, intertidal EM6
Estuarine, intertidal EM1
Estuarine, intertidal EM
Estuarine, intertidal BB2
COMMENTS ON HABITAT ASSOCIATIONS -
The major habitat that R.l. yumanensis is associated with in the
U.S. can be described as palustrine persistent emergent wetland (16),
primarily arid riparian habitats within the desert shrub rangeland
vegetation classification. The wetland classification consists of
non-tidal wetlands dominated by persistent emergent plants (cattails
and bulrushes). This wetland may be found adjacent to the river
channel but is primarily found in large impoundments, such as behind
dams and in backwaters where water is slow moving and the channel is
shallow. The rail retreats from the majority of its breeding range in
the U.S. from October through March. Only near Yuma and the Salton
Sea are individuals found during the winter months in the U.S.
Apparently, some of the U.S. birds winter in western Mexico (17).
Here the rail is probably associated with intertidal estuarine
persistent emergent wetlands and estuarine broad-leafed evergreen
wetlands (e.g., mangroves; Rhizophora sp. and Avicennia sp.).
Along the lower Colorado River in the U.S., R.l. yumanensis is
associated with dense cattail/bulrush marsh vegetation at all
seasons. This information is based on a three-year quantitative study
of clapper rail occurrence in all available marsh situations
represented from 40 study areas along the lower Colorado River by
Anderson and Ohmart (10). Although rails did occur in other types of
marsh during the breeding season, those marshes with the highest rail
densities during this season tend to have the largest rail densities
during all seasons. The converse is true for marshes with low
densities.
During winter, rails were found on only 6 of the 40 study areas.
All of these study areas are located primarily near Yuma and Imperial
NWR. During winter, correlation with dense cattail/bulrush is higher
Habitat Associations - 1 than during any other season. Rails also tend to be associated with
marshes and trees nearby, but this is not statistically significant.
During spring, in addition to being associated with dense stands
of cattails/bulrush, rails are found in higher densities than
expected in one study area with dense stands of reed (Phragmites
australis) and in two study areas with moderately dense cattail
interspersed with open water.
During summer, correlation with dense cattail/bulrush marshes
remains significant but is lower than during any other season. Rail
densities are also positively correlated with sparse cattail/bulrush
marshes <1 m tall. Consequently, occurrence of rails in various marsh
situations is broadest during summer. Also densities of rails are
highest during this season.
During late summer and fall, rail densities are again positively
associated only with dense cattail/bulrush marshes. However, rails
are negatively associated with marshes with invading trees and
grasses. During this time breadth of habitat use declines compared to
summer, but is broader than that found during winter and spring.
Certain study areas are found to consistently deviate from
expected values in rail densities. Three transects had consistently
higher densities of rails than predicted. One of these transects has
a large proportion of reeds; the other two are rather sparse cattail
marshes. One study area had consistently fewer rails than expected
even though it is densely covered with cattail/bulrush. This marsh
was smaller than average and has steep banks.
Size of marsh study area was not a significant factor associated
with density estimates. That is, study areas between 0 and 9.90
ha and those 0.10 ha did not produce densities deviating significantly
from that expected by chance alone. Steepness of riverbank slope also
was not significantly associated with predicted densities.
During the breeding season, rail densities were as high as 8
birds/10 ha. During winter, rail densities ranged from 0.2 to 2.8/10
ha where rails were detected.
Another study of R.l. yumanensis near the north end of the lower
Colorado River study area at Topock Marsh revealed that rails were
most numerous in moderately dense cattail/bulrush marshes (18). A
third study at the Salton Sea found rails to be in higher densities in
the densest cattail stands while they did not use bulrush to any
significant extent, possibly because bulrush marshes were frequently
dry (12). These three studies (the lower Colorado River, Topock
Marsh, and Salton Sea) represent the only quantified systematic field
studies for which conclusions may be drawn on R.l. yumanensis habitat
use of marshes.
Data from nearly the entire geographical range of this species
within the U.S. indicated that although rails are primarily associated
with dense marsh vegetation, they regularly reach greatest densities
in some cattail/bulrush marshes of only moderate foliage density.
The data also indicate that rails occur in vegetation other than dense
cattail, including dense reed and sparse cattail/bulrush, where food
items may be locally abundant. From the Colorado River analysis,
rails are associated with dense emergent vegetation and plant species
composition is not a critical feature.
Another feature found to be very important at Topock Marsh and at
the Salton Sea was that rails require high ground within the marsh,
especially during the breeding season. Downy plumaged chicks become
quickly saturated when wet, which may result in drowning. Also, high
ground is likely important for keeping eggs above the waterline.
Although not quantified in the Colorado River study, this factor is
undoubtedly critical throughout the range of R.l. yumanensis.
Steepness of banks adjacent to a marsh was suggested in the
Topack Marsh study to be negatively associated with rail densities.
Habitat Associations - 2 The Colorado River study shows no relationship with bank slope, but
where there is no dry interface between the banks and the water, the
water habitat value is probably reduced. Rails require this dry
interface for walking and foraging, especially during high water
levels. Even where there is a very narrow (25 cm) dry interface
between bank and water marsh quality probably is unaffected.
Only a few thousand hectares of breeding habitat is available to
R.l. yumanensis and most of it is on the lower Colorado River.
Although the construction of hydroelectric dams has increased the
total amount of marsh habitat (05,13), future river management plans
may severely imperil much of this vegetation. Most of the high-use
marsh habitat is within boundries of National Wildlife Refuges; that
lying outside of protected areas is threatened by development or
modification. Habitat within refuges is subject to damage when
prolonged extensive water releases from dams cause flooding that
results in the death of emergent vegetation and elimination of high
ground needed for successful breeding. Such releases in 1983 and 1984
apparently caused a significant reduction in breeding succcess (19).
Future study should concentrate on the actual effects of high
water on clapper rail breeding success along the entire Colorado
River. In addition, no information exists on the status and habitat
use of the breeding birds in Mexico and also on the entire population
wintering in Mexico.
Principle land use (up along the lower Colorado River) along the
riverine/palustrine habitats include grazing, irrigated farmland
(citrus and vegetables), mixed urban development, and industrial/
residential sewage outfalls. Land use along the habitats in Arizona
are primarily grazing.
Habitat Associations - 3 (DRAFT) - Food Habits
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
LIFESTAGE FOOD FOOD PART
General Arthropods
General Molluscs
General Worms
General Fish
General Amphibia
General Crustaceans
Food Habits - 1 (DRAFT) - Environment Associations
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
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
Environment Associations - 1 (DRAFT) - Life History
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
Ohmart and Tomlinson (20) found that R.l. yumanensis ate mainly
crayfish (Procambarus sp. and Oropectes sp.) on the Colorado River
north of Mexico. In the Topock Marsh study, crayfish densities were
higher in moderately dense cattail than in dense cattail stands. In
the Salton Sea study crayfish were most abundant in dense stands of
cattail. In these two studies, rails were most dense where crayfish
were most abundant. Thus, occurrence of rails seems very closely tied
to the abundance and availability of crayfish. This factor may
explain the occurrence or rails in other marsh types where crayfish
may be locally common, whereas the lack of crayfish may explain rail
absence in seemingly suitable marshes. The measurement of rail
densities at night may indicate that rails may forage in more open
areas after the hot sun goes down.
Crayfish, like emergent vegetation and the rails themselves, are
apparently recent invaders to the northern reaches of the Colorado
River valley. Crayfish apparently were absent on the lower Colorado
River prior to 1900 (20). In addition, Grinnell (06) commented on the
suprising lack of invertebrate species and numbers during his Colorado
River trip in 1910. In recent years, crayfish have become relatively
common through introduction and/or natural expansion. The increase of
this major food item, combined with the creation of stable marsh
habitat have undoubtedly contributed to the present range of R.l.
yumanensis. The presence or absence of crayfish, therefore, may be
the ultimate feature determining rail occurrence in various marshes
along the Colorado River and adjacent drainages.
Other food items found in R.l. yumanensis (12 specimens; 20)
along the Colorado River north of the Delta included isopods, beetles,
damselfly nymphs, grasshoppers, spiders, fresh-water clams,
unidentified mammal bone, and plant seeds. Of 10 specimens examined
north of the Gila-Colorado River confluence, 95 percent of the diet
by volume consisted of crayfish. Two specimens from the Gila-Colorado
River confluence had 49 percent isopods and 50 percent fresh-water
clams. From the Colorado Delta in brackish water, four specimens
examined were found to have broader diets consisting of water beetles
(57 percent), unidentified fish (32 percent), leeches (4 percent),
plant seeds and twigs (4 percent), dragonfly nymphs (2 percent), and
shrimp (1 percent) (20).
HOME RANGE/TERRITORY:
Two studies have quantified territory size. Bennett and Ohmart
(12) at the Salton Sea found a range from 0.27 ha to 0.71 ha with an
average of 0.48 ha. There was no difference in territory size to
home range substantially higher from 0.13 ha to 3.59 ha with a mean of
1.44 ha.
Smith (18) found no overlap in territory among adjacent pairs nor
did he find shared boundries. In contrast, Bennett and Ohmart (12)
found shared boundries, but again no overlap. Bennett and Ohmart (12)
comment further that territories with adjacent neighbors were
significantly smaller than territories with no neighbors at the Salton
Sea. In addition, rails in dense cattail had significantly smaller
Life History - 1 (DRAFT) - Life History
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
territories than rails found in sparse cattail at the Salton Sea.
PERIODICITY:
Peak activity during late spring and summer along the lower
Colorado River and the Salton Sea was based upon responses to taped
clapper rail calls (17,18,12). R.l. yumanensis respond or give
unsolicited calls most often between 0500 to 0830 and from 1800 to
2030. This suggests a crepuscular activity pattern for the species;
however, birds may call during any portion of the day or night
indicating that they may be active anytime during a given 24 hour
cycle. Also, foraging activity may not coincide with calling
activity. There is little documentation for this population of
foraging behavior, but other clapper rail populations do exhibit
extensive nocturnal activity in search of food items (04). The cycle
of crayfish in this area (i.e., nocturnal or crepuscular) may coincide
with rail activity patterns also.
MIGRATION PATTERNS:
R.l. yumanensis on the lower Colorado River is largely migratory,
leaving the U.S. in October and returning by April. Some birds winter
locally at the Salton Sea and from Imperial NWR south to the U.S.-
Mexican border. Tomlinson and Todd (17) found the species to be
common at the Colorado River Delta with the Gulf of California during
summer, and suspected that they winter there as well as south to
Guaymas, Sonora and possibly Baja California. However, actual
verified winter reports are still lacking from Mexico.
COVER/SHELTER REQUIREMENTS:
Cover shelter requirements are basically reflected in habitat
associations for the species. Usually emergent vegetation are
adequate to conceal rails. Occasionally rails may be found in flooded
stands of riparian vegetation, but this occurs very rarely. Rails, in
general, remain hidden within and under vegetation of 1 m or higher.
REPRODUCTIVE SITE REQUIREMENTS:
Bennett and Ohmart (12) at the Salton Sea found all but one of
nine nests in stands of cattail. The nest constituting the lone
exception was constructed of dry cattails but was located at the base
of a salt cedar (Tamarix chinensis) adjacent to a flooded cattail
stand. Both Bennett and Ohmart (12), and Smith (18), comment on the
importance of high ground in nesting areas. When the ground
underneath the nests was covered by water, nest were attached to
vegetation above the water surface. Bennett and Ohmart (12) observed
such nests to have a ramp from which adults could enter and leave the
nest.
REPRODUCTIVE CHARACTERISTICS:
Little is known about the breeding ages and pair formation
behavior in R.l. yumanensis. Paired birds emit different calls than
solitary birds. One brood may be produced per pair per year. The
female is primarily responsible for care of eggs and young. Nesting
commences March to May with most eggs hatching during the first week
of June (12). Average clutch size found prior to hatching was
Life History - 2 (DRAFT) - Life History
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
Life History - 3 (DRAFT) - Life History
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
approximately 8 eggs per nest (12). Abbott (11) found average clutch
size to be 6.5 eggs per nest. Hatching dates range from May 19 to
June 14. Hatching success at the Salton Sea was 90 percent.
PARENTAL CARE:
Young are precocial and follow the adult through the marsh within
48 hours after hatching. Adults lead the young to productive feeding
grounds where they quickly learn to feed on their own. As with many
precocial birds with large clutch sizes, clapper rails suffer high
young mortality. Within one month after hatching, only a maximum of
two young birds usually accompany the adults when often eight were
hatched per clutch (12).
POPULATION BIOLOGY:
Clapper rails are found to be solitary, in pairs, and in family
groups, but are not social. Fluctuations in population size from year
to year are undocumented, but may occur in response to habitat changes
and/or fluctuations in prey abundance. The size of any particular
marsh does not seem to have an effect on wheather rails are present or
absent, but the marsh size and density of vegetation and prey does
affect territory size (12).
Factors affecting dispersal are not presently understood,
especially with respect to most other clapper rail populations which
are sedentary. Huey's (04) comments about Colorado River Delta birds
annually dispersing north due to very high water flows, no longer
apply as the Colorado River did not flow into Mexico from the 1940's
until 1983. Rails are continually found in newly created marshes
such as those at the Salton Sea, CA, and Picacho Reservoir, AZ, yet it
is unknown wheather original colonizers are young birds, older birds,
or both. Whatever the causes of dispersal, R.l. yumanensis is an
opportunistic race of clapper rail.
SPECIES INTERRELATIONSHIPS:
The available evidence indicates that R.l. yumanensis
distribution in the U.S. is directly dependent upon the presence and
abundance of its major food item, crayfish. This population seems to
be intricately related to crayfish in such a way that locally the
rails will deviate from their normal habitat configuration to track
this resource if the resource is more abundant in an alternative
habitat. Even though the species is highly associated with dense
stands of cattail and/or bulrush, other habitats will be utilized
rather than the "preferred" habitats if crayfish are abundant.
Two other rail species breed in areas occupied by R.l.
yumanensis. Viginia rails (Rallus virginianus) are found to breed in
the same marshes as R.l. yumanensis in the Bill Williams Delta, and
the two coexist elsewhere. Black rails (Laterallus jamaicensis) occur
locally from Imperial Dam south to Yuma and are found in the same
geographical areas as R.l. yumanensis but prefer short-statured stands
of three-square bulrush (Scirpus americanus) over the taller emergent
vegetation that R.l. yumanensis prefers (21).
OTHER LIFE HISTORY DESCRIPTORS:
None.
Life History - 4 (DRAFT) - Life History
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
Life History - 5 (DRAFT) - Management Practices
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Controlling/Restricting Boating Activities
Beneficial Developing/maintaining stream structures
Beneficial Maintaining/Controlling Water Flow
Beneficial Developing/maintaining/protecting wetlands
Beneficial Land Acquisition
Beneficial Controlling pollution [thermal, chemical, physical]
Beneficial Controlling/Restricting Pesticide Use
Beneficial Maintaining Later Stages of Succession
Beneficial Restricting Poaching
Beneficial Controlling/Removing Native Vertebrates
Adverse Boating
Existing Boating
Adverse Food Supply Reduction
Existing Food Supply Reduction
Adverse Rural Residential/Industrial Areas
Existing Rural Residential/Industrial Areas
Adverse Recreational development
Existing Recreational development
Adverse Siltation
Existing Siltation
Adverse Salinity alteration
Existing Salinity alteration
Adverse Draining wetlands, marshes, ponds, lakes
Existing Draining wetlands, marshes, ponds, lakes
Adverse Strip mining
Existing Strip mining
Adverse Water Level Stabilization
Existing Water Level Stabilization
Adverse Water Level Fluctuation
Existing Water Level Fluctuation
Adverse Flooding
Existing Flooding
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 Developing/maintaining stream bank vegetation
Existing Developing/maintaining stream bank vegetation
Adverse Shoreline modification/development
Existing Shoreline modification/development
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
Adverse Erosion
Management Practices - 1 (DRAFT) - Management Practices
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
RESULT MANAGEMENT PRACTICE
Existing Erosion
Adverse
Existing
Adverse Vegetation Composition Changes
Existing Vegetation Composition Changes
COMMENTS ON MANAGEMENT PRACTICES -
The past status of the Yuma clapper rail (R.l. yumanensis) is
outlined by Ohmart and Smith (05) and summarized here are the details
of that report. The early field biologists on the Colorado River,
many of whom were familar with clapper rails, did not record them.
Grinnell (06) and his party floated the river in 1910 from Needles, CA
to the Mexican border. During his three-month survey of the lower
Colorado River vertebrates, he found no evidence that R.l. yumanensis
existed along the river. He described a rather depauperate waterbird
fauna compared to today and his description of the river's plant
associations indicated that potentially suitable marshes were very
small and very local in distribution. A passage from Grinnell
(06:72-73) summarizes the comments of all the field biologists working
along the lower Colorado River in the late 19th and early 20th
centuries on the extent of marshes and marsh formation before the
major dams were completed. What oxbows were found, mostly were
lifeless alkali flats or lagoons surrounded with terrestrial
riparian vegetation. Grinnell makes mention of the fact that there
was an unexpectedly depauperate invertebrate fauna, especially in the
afforementioned alkali flats. The high salinity levels of these areas
restricted the occurrence of fresh-water crustaceans that would have
been important food sources (and the ultimate factor associated with
rail occurrence) for any rails potentially found along the river.
Crayfish (Procambrus sp. and Oropectus sp.) constitute the most
important food item for R.l. yumanensis and there is no evidence that
crayfish were present along the river until after the 1920's. In a
few places Grinnell did find small marsh areas that were maintained by
seepage; these were near the edges of the valley, and, therefore,
little affected by the fluctuating river channel.
The first specimens of the species were taken near Laguana Dam in
1921 (01). Laguana Dam was completed in 1909, a year before
Grinnell's trip. Grinnell described the river above the dam as
broadening out, killing the native riparian vegetation with the
formation of "vast mudflats growing up to arroweed" (06:16). Marsh
vegetation became established along the canals near Laguana Dam some
10 to 11 years later. Huey (04:275-277), who with Canfield collected
the first R.l. yumanensis specimens, comments that by 1924 he
considered the center of rail abundance to be in the Delta of the
Colorado River. These lower reaches of river, during flood stage in
May and June, may have been unsuitable for nesting, thus forcing some
rails up the river seeking other suitable localities. The water was
unusually high during the time the rails were collected in 1921 and
they were obtained unusually far up the river. Again, with the dam,
permanently high water was allowing for extensive marsh formation;
Management Practices - 2 (DRAFT) - Management Practices
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Date 14 MAR 96
including along canals where the first rails were found. In Huey's
opinion, rails only came as far north from the Delta each summer as
siutable habitat for nesting was found. Huey also predicted that the
rail would be found extending its range where extensive bulrush
(Scirpus sp.) marshes were forming, such as at the Salton Sea. The
presence of R.l. yumanensis north of Laguana Dam followed
consecutively a few years after the completion of Parker, Imperial,
and Headgate Rock Dams in 1938, 1939, and 1942 respectively. The
operation of the big dams, Imperial and Parker, slowed and stopped
river flow allowing the sediment load to build. The resulting
sandbars provided suitable substrate for the growth of cattails
(Typha latifolia and T. domingensis) and bulrush. This emergent
vegetation began to stabilize, thus transforming the sandbars into
marshes. The first sightings of the rail in the Bill Williams Delta
occurred 16 years after the closure of Parker Dam. The formation of
Lake Havasu slowed the silt-laden waters of the Bill Williams and
Colorado Rivers to form large deposits in the now-termed Bill Williams
"Arm" of Lake Havasu. After marsh development occurred, Monson (07)
first observed a pair of rails in the "Arm" on May 12, 1954. An
immature bird was collected there August 16, 1954. Monson had
visited the area regularly on an annual basis prior to the 1954
observations.
Other early sightings of R.l. yumanensis by Monson include one
near Headgate Rock Dam on August 12, 1946, and subsequently in the
same area July 9, 1948 (adult and three young). July 17, 1948 (two
adults), March 18, 1949 (one adult). Farther north the species was
not located until 1966 at Topock Marsh (08). Monson's (09) general
impressions are that the population's distribution was very localized
prior to about 1940 and has since become more widespread.
Given these observations, there is little question that the
construction of dams along the river and subsequent river management
have allowed for the formation of large stable stands of suitable
marsh habitat north of the Colorado River Delta. This, in combination
with the expansion of crayfish as an important food source, has led
to the northward expansion of the rail. If R.l. yumanensis occurred
as a breeding population along the lower Colorado River in the U.S.
before major marsh formation, it was much more local.
The present population size on the lower Colorado River is
estimated to be between 700 and 800 individuals (10). The present
distribution and population size is limited by, and threatened from,
continuing river managemnt activities such as dredging,
channelization, and stabilization of banks by rip-rapping. These
activities are detrimental to marsh habitat formation. Future high
water flows are likely, and dramaticlly interfere with breeding. In
addition, high water flows will result in greater pressure being
exerted on water management agencies to increase channelization and
bank stabilization activities which will result in a large reduction
of available marsh habitat.
Populations of R.l. yumanensis have occurred at the Salton Sea
since at least 1940 (11) and presently appear stable, with at least
200 individuals there in 1977 (12). Since the present Salton Sea was
not in existence until 1907, and extensive marshes there were not
present until the 1920's, the presence of rails confirm the range
Management Practices - 3 (DRAFT) - Management Practices
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Species Id ESIS102002
Date 14 MAR 96
extensions prdicted by Huey in 1924. Recent expansions also have been
noted along the Gila and Salt rivers as far east as Picacho Reservoir
and are likely the result of recent marsh formantion and stabilization
in many of these areas. Marshes along the Gila and Salt Rivers were
highly transitory as they were quickly removed through river channel
movements or as they rapidly succeeded toward xeric communities after
evaporation (06,13,14). These marshes (similar to oxbows and
backwaters found on the Colorado River) sould not be confused with the
permanent cienegas found primarily at higher elevations and mostly
within southeastern AZ (15).
Only a few thousand hectares of breeding habitat is available to
R.l. yumanensis and most of it is on the lower Colorado River.
Although the construction of hydroelectric dams has increased the
total amount of marsh habitat (05,13), future river management plans
may severely imperil much of this vegetation. Most of the high-use
marsh habitat is within boundries of National Wildlife Refuges; that
lying outside of protected areas is threatened by development or
modification. Habitat within refuges is subject to damage when
prolonged extensive water releases from dams cause flooding that
results in the death of emergent vegetation and elimination of high
ground needed for successful breeding. Such releases in 1983 and 1984
apparently caused a significant reduction in breeding succcess (19).
Although R.l. yumanensis is restricted to a rare habitat type
(and therefore, the population size itself remains low), as suitable
marsh habitat expands the rail population expands also. Thus, R.l.
yumanensis is an opportunistic race of clapper rail, but is highly
susceptible to management regimes that threaten its habitat.
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1983. Yuma Clapper Rail Recovery
Plan. U.S. Fish and Wildlife Service, Albuquerque, NM. 51 pp.
The primary objective of the Recovery Plan was to preserve and
maintain good quality habitat and a breeding population of 700 to
1,000 Yuma clapper rails (YCR) in the U.S. The habitat and population
should be monitored every 5 years using standardized methods. Local
surveys in areas where immediate threats to YCR's exist should be
conducted annually. Mexican habitat and breeding populations just
south of the international border should also be inventoried
regularly. Agencies managing public lands with YCR habitat should
incorporate rail management techniques in their master management
plans. As of 1983, an unwritten understanding exists stating that the
Bureau of Reclamation will maintain a flow through Parker Dam of at
least 2,000 cf/s. Water management needs outlined by the Recovery
Plan include efforts to:
1) Assess the minimum and maximum flows through Davis, Headgate
rock, Imperial, and Laguna Dams needed to maintain rail
habitat.
2) Summarize Colorado River flow information for the past 10
years and relate it to the status of the YCR.
3) Establish a formal agreement between the Bureau of
Reclamation, Corps of Engineers, the Fish and Wildlife
Management Practices - 4 (DRAFT) - Management Practices
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Species Id ESIS102002
Date 14 MAR 96
Service, and the States of Arizona and California to assure
that water flow remains within determined limits needed to
maintain quality YCR habitat.
Surveys should also be conducted within the range of the YCR to
determine if other areas could also support these rails.
Studies to determine breeding season biological requirements of
the YCR are needed. Information needed includes:
1) Adaptability of YCR to alternate foods besides the preferred
crayfish.
2) Nesting chronology.
3) Calling behavior in relation to nesting.
4) Life history patterns with emphasis on life span, mortality
rates, and causes of death.
5) A summarization of habitat needs of breeding birds and a
management document prepared on these results.
Winter habitats of the YCR are also important. Recovery efforts
planned include:
1) Determination of movement patterns of YCR using
radiotelemetry.
2) The determination of wintering areas and populations within
the U.S. and protection of those areas.
3) Determination of wintering areas in Mexico through telemetry.
4) Studies of the extent of Mexican wintering habitat.
5) Establishment of a U.S./Mexican agreement to preserve and
manage wintering YCR habitat in Mexico.
6) Management of YCR wintering habitat in Mexico.
7) Public awareness of the uniqueness of the YCR should be
increased through the use of local, State and National
broadcasts and printed media.
Although not specifically mentioned in the Recovery Plan,
considerations for recovery include; the restricting of poaching by
enforcing applicable laws, maintaining later stages of succession of
the non-forested wetland habitat (a climax community), restricting
pollutants and pesticide use, removing native mammalian predators
and controlling boating activities. Wetland management, maintaining
water flows, and favorable bank or channel modification are also
desirable tools for recovery of the YCR.
The Recovery Plan called for initiating efforts to downlist YCR.
These plans were stalled in 1984 by concerns caused by extensive
flooding along the Colorado River and delayed further until the
ongoing study is completed. The major ongoing recovery effort is an
intensive field study, including the use of radiotelemtry, to fulfill
some of the information needs outlined in the Recovery Plan. It has
been found that more YCR's winter in the U.S. than previously
thought. Mammalian predation is higher than expected. Efforts to
reach an agreement with Mexican officials to expand studies into that
country have not yet been successful. Completion of the current study
will result in revision of the Recovery Plan and perhaps alter the
step-down outline.
Future study should concentrate on the actual effects of high
water on clapper rail breeding success along the entire Colorado
River. In addition, no information exists on the status and habitat
use of the breeding birds in Mexico and also on the entire population
Management Practices - 5 (DRAFT) - Management Practices
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Species Id ESIS102002
Date 14 MAR 96
wintering in Mexico.
Management Practices - 6 (DRAFT) - References
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Dickey, D.R. 1923. Description of a new clapper rail from the
Colorado River Valley. Auk 40:90-94.
02 Meanley, B. 1969. Natural history of king rail. N.A. Fauna No.
67. Bureau of Sport Fish and Wildl. USGPO, Washington, DC.
03 American Ornithologists' Union. 1983. Check-list of North
American birds, sixth edition. American Ornithologists' Union;
Washington, DC.
04 Bent, A.C. 1926. Life histories of North American marsh birds.
U.S. National Mus. Bull. 135:1-392, plus 98 pl. [Dover reprint,
1963.]
05 Ohmart, R.D., and R.W. Smith. 1973. North American clapper rail
literature survey. Bur. Rec., Lower CO Reg., Boulder City, NV.
06 Grinnell, J. 1914. An account of the mammals and birds of the
lower Colorado Valley. Univ. of Cal. Publ. Zool. 12:51-294.
07 Monson, G. November, 1984. Personal field notes. AZ State Univ.,
Tempe, AZ.
08 Welch, J.M. 1966. South Region. Audubon Field Notes 20(5):590.
09 Monson, G. and A.R. Phillips. 1981. Revised check-list of Arizona
birds. Univ. AZ Press, Tucson, AZ. 240 pp.
10 Anderson, B.W. and R.D. Ohmart. 1986. Habitat use by clapper
rails in the lower Colorado River Valley. Condor.
11 Abbott, C.G. 1940. Notes from the Salton Sea, California. Condor
42(5):264.
12 Bennett, W.W. and R.D. Ohmart. 1978. Habitat requirements and
population characteristics of the clapper rail in the Imperial
Valley of California. Univ. of CA, Lawrence Livermore Laboratory,
Livermore, CA.
13 Ohmart, R.D., W.O. Deason, and S.J. Freeland. 1975. Dynamics of
marsh formation and succession along the lower Colorado River and
their importance and management problems as related to wildlife in
the arid Southwest. Trans. 40 N. Amer. Wild. Nat. Res. Conf.,
Wild. Inst., Washington, DC.
14 Ohmart, R.D. and B.W. Anderson. 1982. North American desert
riparian ecosystems. Pp 433-479. In: Reference handbook on the
deserts of North America. G.L. Bender ed. Greenwood Press,
Westport, CT.
15 Hendrickson, D.A. and M.L. Minkley. 1986. Cienegas-vanishing
climax communities of the American Southwest. Desert Plants.
16 Cowardin, L.M., V. Carter, F.C. Golet, and E.T. La Roe. 1979.
Classification of wetlands and deepwater habitats of the United
States. FWS/OBS-79/31, Dec. 1979, Washington, DC. 103 pp.
17 Tomlinson, R.D. and R.L. Todd. 1973. Distribution of two western
clapper rail races as determined by responses to taped calls.
Condor 75:177-183.
18 Smith, P.M. 1975. Habitat requirements and observations on the
clapper rail. MS thesis, AZ State Univ., Tempe, AZ.
19 Powell, R. November, 1984. Pers. comm. Yuma Clapper Rail
Recovery Team Leader. CA Dept. of Fish and Game, Blythe, CA
92225.
References - 1 (DRAFT) - References
Species RAIL, CLAPPER, YUMA
Species Id ESIS102002
Date 14 MAR 96
20 Ohmart, R.D. and R.E. Tomlinson. 1977. Foods of western clapper
rails. Wilson Bull. 89:332-336.
21 Repking, C.F. and R.D. Ohmart. 1977. Distribution and density of
black rail populations along the lower Colorado River. Condor
79:486-489.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Powell, R. November, 1984. Pers. comm. Yuma Clapper Rail
Recovery Team Leader, CA Dept. of Fish and Game, Blythe, CA
92225.
02 Tomlinson, R.E. and R.L. Todd. 1973. Distribution of two western
clapper rail races as determined by responses to taped calls.
Condor 75:177-183.
03 Todd, R.L. November, 1984. Pers. comm. AZ Game and Fish Dept.,
Nongame Branch, 2222 W. Greenway, Phoenix, AZ 85012.
04 Refuge Manager. 1984. Pers. comm. Imperial NWR, Martinez Lake,
AZ.
05 Refuge Manager. 1984. Pers. comm. Havasu NWR, Needles, CA.
06 Refuge Manager. 1984. Pers. comm. Cibola NWR, Cibola, AZ.
07 Busch, D.E. November, 1984. Pers. comm. Environment Office,
USBR, Boulder City, NV 89005.
08 Refuge Manager. 1984. Pers. comm. Salton Sea NWR, Westmoreland,
CA.
09 Manager, Wister Waterfowl California Management Area, Niland, CA.
10 Guenther, H. November, 1984. Pers. comm. Wellton-Mohawk
Irrigation District, Wellton, AZ.
11 Grinnell, J. 1914. An account of the mammals and birds of the
lower Colorado Valley. Univ. of Cal. Publ. Zool. 12:51-294.
12 Dickey, D.R. 1923. Description of a new clapper rail from the
Colorado River Valley. Auk 40:90-94.
13 American Ornithologists' Union. 1983. Check-list of North
American birds, sixth edition. American Ornithologists' Union;
Washington, DC.
References - 2