(DRAFT) - Taxonomy
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
TAXONOMY
NAME - CROW, MARIANA
OTHER COMMON NAMES - CROW, MARIANA; CROW, MARIANAS; CROW and GUAM; AGA
ELEMENT CODE -
CATEGORY - Birds
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - AVES,
ORDER AND SUBORDER - PASSERIFORMES,
FAMILY AND SUBFAMILY - CORVIDAE,
GENUS AND SUBGENUS - CORVUS,
SPECIES AND SSP - KUBARYI,
SCIENTIFIC NAME - CORVUS KUBARYI
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Mariana Crow
Corvus kubaryi Reichenow, 1885
KINGDOM: Animal GROUP: Bird
PHYLUM: Chordata CLASS: Aves
ORDER: Passeriformes FAMILY: Corvidae
A small black crow with a slight greenish black gloss on the
head; back, wings and tail with bluish-black gloss; underparts with
dull greenish-black gloss; bases of feathers light grayish, more
nearly white on neck producing a somewhat ragged appearance; nasal
bristles short but extending over nostrils and base of culmen; bill
and feet black; iris dark brown. Female smaller. Immature resembles
adult, but feathers with less gloss; wings and tail browner (01), but
this characteristic may be of limited use in the field (02).
Fledglings plumage is "ragged" looking, with white showing through
from the bases of the feathers at numerous locations on the neck,
back, and breast. Lower mandible near base has pink-tan showing (03).
Taxonomic names and synonyms that have been ascribed to
Corvus kubaryi are listed below (01).
Corvus solitarius Kittlitz 1836
Taxonomy - 1 (DRAFT) - Taxonomy
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
Corvus spp. Hartlaub 1854
Corvus kubaryi Reichenow 1885
Corone phillipina Wiglesworth 1891
Corone kubaryi Wiglesworth 1891
Corvus kubaryi Hartert 1898
Other common names used in the literature for Corvus kubaryi are
Guam Crow and Marianas Crow. The indigenous people of Guam, the
Chammarros, call Corvus kubaryi "Aga".
There are 19 specimens in the American Museum of National
History, New York (04), 26 at the U.S. National Museum of National
History, Washington, D.C. (01), and 1 at the Bishop Museum (22).
There may be additional specimens in other museums. Photographs of
the Mariana Crow are held by the Guam Division of Aquatic and
Wildlife Resources.
Taxonomy - 2 (DRAFT) - Status
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
STATUS
Coded Status
E: Federal Endangered
Non-consumptive recreational
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Mariana crow (Corvus kubaryi) 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
Territory of Guam and the Commonwealth of the Northern Mariana
Islands (Rota).
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.
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.
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:
Status - 1 (DRAFT) - Status
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
TERRITORY: Guam
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: Department of Agriculture,
Division of Aquatic and Wildlife
Resources
STATE STATUTE: Endangered Species Act of Guam, 1981;
Guam Public Law 15-36, June 18, 1979.
COMMONWEALTH: Commonwealth of the Northern Mariana Islands
DESIGNATED STATUS: None.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
The species is not listed by CITES, but is listed as Endangered
in the IUCN Red Data Book.
ECONOMIC STATUSES:
On Guam this species was a common, endemic insectivore sought
by bird watchers. The species was also important as a dispersal
vector for seeds of native forest trees. In the past hunting may
have added an additional stress on the population, but presently
there is no evidence to suggest illegal hunting is responsible for
the recent declines.
79/05/18:44 FR 29128/29130 - Notice of review of status
79/06/13:44 FR 33915 - Extension of comment period.
81/05/12:46 FR 26464/26409 - Petition acceptance and status review
83/11/29:48 FR 53729/53733 - Proposed listing
84/01/20:49 FR 02485/02488 - Notice: proposed listing warranted
84/08/27:49 FR 33881/33885 - Final rule, listed as Endangered
Status - 2 HABITAT ASSOCIATIONS
HABITAT - TERRESTRIAL
TERRESTRIAL
LAND USE -
Orchards, Groves, Vineyards, Nurseries,
Evergreen Forest Land
Mixed Forest Land
COMMENTS ON HABITAT ASSOCIATIONS -
The Mariana crow is still found in the wild on Guam, but is
primarily confined to limestone forest and mixed forest areas in
extreme northern Guam. It also utilizes old coconut plantations in
Northern coastal Guam. The Mariana crow's preference for mature
native forest on Guam has been noted by several authors (11,12,13).
Baker (01) found the crow confined to coconut plantations and forest
areas and only infrequently found it in areas of human habitation. In
1983 during a survey of northern Guam by the Guam Dept. of Aquatic and
Wildlife Resources (14) and Jenkins (02), this latter observation was
confirmed by noting the presence of the crow in mature forest (native,
mixed woodland and second growth) on Anderson Air Force Base and it's
absence in areas of human habitation such as base housing, active
airfield areas, and other locations around buildings with high human
usage. Tomback (15), during a two week study on Guam and Rota in
July of 1980, listed 13 plant species used by the crow for foraging
and other activities. Eleven of these species were native and typical
of limestone forest and coastal strand. The two exceptions were
Leucaena leucocephala and Mangifera indica. During a study of the
crow in the fall of 1985, Michael and Beck (16) found the crow
restricted to mature forest in the Northwest Field and Conventional
Weapons Storage Area on Anderson Air Force Base (AAFB), primarly
using emergent trees such as Ficus prolixa and Elaeocarpus joga
from which to view and defend their territory and in which to build
nests. Both Baker (01) and Jenkins (02) reported crow nests in Ficus
prolixa tree in an area of mature mixed woodland-native forest on
Northwest Field, AAFB. The second pair unsuccesfully incubated eggs
in at least 10 successive nests in at least 6 different emergent
Elaeocarpus joga trees in native forest at the Conventional
Weapons Storage area on AAFB over a 6 month period.
Habitat usage of the Mariana crow on Rota has been little
studied, but Baker (01), Pratt et al. (17), and Engbring and Ramsey
(18) found the crow on Rota to be similar to that he observed on Guam.
Tomback (15) found the crow on Rota only in limestone (native) forest
and coastal strand vegetation.
Habitat Associations - 1 (DRAFT) - Food Habits
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
OMNIVORE
LIFESTAGE FOOD FOOD PART
General
General Forb Flowers/Fruit/Seed
General Evergreen Shrubs-Flowers/Fruit/Seed
General Arthropods
General Crustaceans
General Molluscs
General Worms
General Amphibia
General Reptilia
General Aves
Food Habits - 1 (DRAFT) - Environment Associations
Species CROW, MARIANA
Species Id ESIS101032
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 Coastal Features: Vegetated offshore islands
Environment Associations - 1 (DRAFT) - Life History
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
The Mariana crow is an omnivorous, opportunistic feeder that is
known to feed on insects, lizards, hermit crabs, fruits, seeds,
flowers, and according to Jenkins (02), occasionally foliage and bark.
Tomback (15) also observed the crow feeding on leaves and possibly
bark. It may also consume worms, mollusks, and amphibians. Michael
and Beck (16) during a study in the fall of 1985, found the crow
feeding primarily on animal matter and did not observed it feeding on
bark or foliage although much time was spent there by the crow
apparently searching for insects. Fledglings on Rota were observed
tearing up dead bark and leaves apparently in search of insects (03).
It forages on the ground as well as in the forest canopy (02,19). The
Mariana crow also apparently feeds on other birds eggs (20).
HOME RANGE/TERRITORY:
On Guam, Michael and Beck (16) during a study in the Fall and
Winter of 1985 observed the following territorial behavior. The
Mariana crow defends its nesting-foraging territory with both male
and female participating. Their two to three acre territory often
contains several emergent trees, typically Elaeocarpus joga or
Ficu spp. from which the crows view the territory and call to warn
intruders, both individuals and groups, before actively chasing and
sometimes physically attacking them. There are often several old
nests in a territory in addition to an active one. It is not known
if there is seasonal variation in the size or shape of territories.
PERIODICITY:
The Mariana crow is a diurnally active species. While breeding
appears to be year round (see subtitle of this field "REPRODUCTIVE
CHARACTERISTICS"), Marshall (13) has suggested that the crow does not
breed during June, July, and August.
MIGRATION PATTERNS:
The Mariana crow apparently does not seasonally migrate although
nothing is known concerning possible movement, if any, between Guam
and Rota (08). As many as 68 individuals have been observed at
roosts sites (14). The movements of these individuals (apparently
not breeding individuals) is not currently understood.
COVER/SHELTER REQUIREMENTS:
No information exists in the cover requirements for this species
but see the field "N-HABITAT" (Habitat Associations) for a description
of habitat preferences.
REPRODUCTIVE SITE REQUIREMENTS:
Typically, the crow builds a stick nest on a forking horizontal
branch on the outer part of the tree strong enough to support the
large structure (16). The nests are located high in emergent Ficus
or Elaeocarpus trees (02,16) in mature forest. The nest are 2 to 2.5
foot in diameter and is made of dead sticks approximately 1/4 inch in
diameter, with a four to five inch cup lined with grasses (16). Nest
Life History - 1 (DRAFT) - Life History
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
site locations ranged from 15 feet to 55 feet high (16). Currently,
the Guam (only) population is not reproducing, most likely due to
egg/hatchling predation by snakes.
REPRODUCTIVE CHARACTERISTICS:
Little is known of the reproductive biology of the Mariana crow.
It apparently nests year-round (02) although Marshall (13) suggested
that this species does not breed in May, June or July. Nesting has
been observed in March (01,03), May, June, Sept., Oct., and Nov. (21),
and October through February (16). Clutch and brood sizes are not
well known (02). One nest was observed on Guam containing one egg in
October 1985 (16). On Rota one adult pair was observed with two
fledglings and another pair with one fledgling in March, 1986 (03).
Jenkins (02) observed a pair of crows with two fledglings and a single
adult with one fledgling. Both adults participate in all aspects of
the construction of the nest (16). The female does all of the
incubating at night and most of the incubation during the day with
the male relieving the female for only short periods of five or ten
minutes at a time (16). While the female does leave the nest during
the day to forage, the male will feed the female on the nest several
times a day (16). Incubation time is unknown but during a study of
the crow on Guam in the Fall-Winter of 1985-86, a crow pair incubated
for as long as 18 days on two ocassions before abandoning the nest
due presumably to predation from the brown tree snake (16).
PARENTAL CARE:
The breeding biology of the Mariana crow is little studied. The
time required for development of the altricial young is unknown.
Both parents participate in the care of the young (02). Apparently
an extensive learning period is necessary for the young (02), with
fledglings closely following their parents, begging for food, and
learning the foraging patterns (02,03). Both parents defend the nest
site, although the male plays a greater role then the female (16).
The duration of the pair bond is unknown.
POPULATION BIOLOGY:
Current limiting factors affecting the Mariana crow on Guam and
Rota are unknown with the exception of the predation by the brown tree
snake reducing the population on Guam (05) as described in field
"N-REASON" (reasons for status). On Guam, the reproductive rate
appears to be very low or non-existant based on the lack of fledglings
found on Guam and the lack of nest success found during a study of the
crow on Guam in the Fall-Winter of 1985-86 (16).
SPECIES INTERRELATIONSHIPS:
Interspecific interactions of the Mariana crow with other forest
birds are common (02). Jenkins reported the crow chasing Mariana
fruit-doves (Ptilinopus roseicapillus). Crows apparently steal other
birds eggs (20). Beck (03) observed the crow on Guam attempting to
rob eggs from a nest of Rufous-fronted fantails (Rhipidura rufifrons
uraniae and then being mobbed by both the fantail pair in question
and an adjacent Guam broadbill (Myiagra freycineti). Micronesian
starlings (Aplonis opaca guami), and the Collared kingfisher
Life History - 2 (DRAFT) - Life History
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
(Halcyon chloris orii), on Rota will chase crows in their territory
(03). Marshall and Beck (03) observed a Micronesian fingfisher
(Halcyon c. cinamomina), pair being successfully displaced from a
territory in which they had previously fledged a chick by Mariana
crows.
The crows are subject to repeated attacks in flight by the
recently intriduced Black drongo (Dicrurus macrocercus) (02), but
Maban (10) concluded that the drongo is not restricting the range of
the crow and other forest birds on Guam.
OTHER LIFE HISTORY DESCRIPTORS:
Other information is available.
Life History - 3 (DRAFT) - Management Practices
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Suppressing wildfire
Beneficial Land Acquisition
Beneficial Reforestation
Beneficial Stocking captive-reared wild-strain animals
Beneficial Controlling/Removing Exotic Vertebrates
Beneficial Controlling/Removing Feral Animals
Adverse Predation
Existing Predation
Adverse Applying pesticides
Existing Applying pesticides
Adverse Exotic/Feral/Introducted Species
Existing Exotic/Feral/Introducted Species
COMMENTS ON MANAGEMENT PRACTICES -
Predation of eggs, young and adults by the introduced
nocturnal brown tree snake (Boiga irregularis), is thought to be
responsible for the present decline of the Mariana crow and other
forest birds on Guam (05). The Mariana crow is apparently not
declining on Rota (06).
Recently, introduced diseases were considered as possible
causes for both the range reductions and extinctions noted for most
native forest birds on Guam, but no infectious organisms have
been isolated on Guam that could account for the decline (05). Feral
dogs, cats and rats which are found on both Guam and Rota are not
thought to be a major factor in the decline of the crow (05).
There have been major changes in Guam's vegetation before,
during, and after World War II (07). However, substantial native
habitat still remains on Guam and habitat degradation is not thought
to be a major factor at present. If present development patterns
continue to reduce and segment the dwindling available mature forest,
recovery of the Mariana crow may be hindered because of it's apparent
requirement of mature forest with little human usage (08).
While pesticides may have been a factor in the past, an intensive
pesticide survey conducted in 1981 on Guam, concluded that pesticides
were not a significant factor at present (09).
While agonistic interactions between the Mariana crow and the
Black Drongo (Dicrurus macrocerus), have been noted (02), Maben (10)
found competition to be an unlikely factor in the decline on Guam.
Hunting may have stressed the crow on both Guam and Rota but
there is no evidence to suggest it was responsible for the recent
decline of the crow on Guam (08).
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1987. Endangered Native Forest Birds
of Guam and Rota, Mariana Islands Recovery Plan. U.S. Fish and
Wildlife Service, Portland, OR. 110 pp.
Management Practices - 1 (DRAFT) - Management Practices
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
Management Practices - 2 (DRAFT) - Management Practices
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
The recent, drastic decline of forest bird populations on Guam
has been one of the most alarming and challenging endangered species
problem of modern times. Current evidence points to an efficient
predator of small birds, the brown tree snake, as the culprit. Once
thought to be relatively resistent to snake predation, the Mariana
crow population on Guam has dwindled to just a few birds. In
contrast, the population on Rota remains healthy. The species is
included in the Endangered Native Forest Birds (for Guam and Rota of
the Mariana Islands) Recovery Plan. The plan recommends among its
primary objectives maintaining the population on Rota at present
levels and to restore the Guam population to a sustainable level, the
minimum number to be determined by further study. In addition, it is
imperative to develop methods of reducing predation by brown tree
snakes; this action would then allow expansion of the wild population
and reintroduction of captive birds back into their historic range.
Down-listing to threatened status would occur once predation from
snakes is under control and crows again occupy all essential habitat.
The recovery plan recommends the following actions for the Endangered
forest birds of the Marianas:
(1) develop cooperative agreements among the USFWS, the Government of
Guam, and the Commonwealth of the Northern Marianas, for protection
and recovery of forest birds;
(2) conduct annual status surveys of endangered forest birds;
(3) develop a captive breeding program for all species;
(4) reduce avian mortality in the field by monitoring for disease,
preventing diseases and their vectors from becoming established,
monitoring for pesticides, and particularly a program for controlling
predation by snakes, specifically by:
(a) research on the biology and ecology of the tree snake,
(particularly in its native geographical range),
(b) develop control methods,
(c) implement control measures, and
(d) prevent transport of snakes to Rota;
(5) protect and manage essential habitat;
(6) conduct additional research necessary for refinement recovery
tasks and goals, including rehabilitating habitat and encouraging
vegetation regrowth in denuded areas, controlling alien organisms,
identifying habitat requirements of endangered birds, and developing
criteria for delisting these endangered species;
(7) develop methods for reintroducing endangered birds to essential
habitat and implement where appropriate; and
(8) develop a public awareness program.
Recovery actions ongoing or accomplished for Guam's forest birds
include:
(1) legal protection and law enforcement,
(2) protection of essential habitat, including establishment of 6
small natural area reserves held by the Territory or by the military,
(3) ongoing captive breeding program (but not yet for the crow),
(4) a completed public education program (which should be reinstated),
(5) and extensive research on avian diseases and biology of the brown
tree snake. Virtually all of these activities have been initiated and
carried out by the Government of Guam, in cooperation with the USFWS.
Management Practices - 3 (DRAFT) - Management Practices
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
Management Practices - 4 (DRAFT) - References
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Baker, R.H. 1951. The avifauna of Micronesia, its origin,
evolution, and distribution. Univ. Kansas Publ., Mus. Nat.
Hist. 3:1-359.
02 Jenkins, J.M. 1983. The native forest birds of Guam. Ornith.
Monogr. No. 31. 61 pp.
03 Beck, R.E. Jr. Unpub. data. Div. of Aquatic and Wildl. Res.,
Dept. of Agric., Agana, Guam 96910.
04 Lanyon, W.E. Pers. comm. Am. Mus. of Nat. Hist., Central Park
West at 79th St., New York, N.Y. 10024.
05 Savidge, J.A. 1986. The role of disease and predation in the
decline of Guam's avifauna. Ph.D. Thesis. Univ. of Illinois,
Urbana-Champaign.
06 Engbring, J. and F.C. Ramsey. In Press. Pacific islands
forest bird survey. Saipan, Tinian, Aguiguan, and Rota.
U.S. Fish and Wildl. Ser., Honolulu, HI. 224 pp.
07 Fosberg, F.R. 1960. The vegetation of Micronesia. Bull. Am. Mus.
Nat. Hist. 119(1):1-75.
08 U.S. Fish and Wildlife Service. 1985. Recovery Plan for the
Native Forest Birds of Guam and Rota, Mariana Islands. Tech.
Draft. U.S. Fish and Wildlife Service, Honolulu, Hawaii. 107 pp.
09 Grue, C.E., C.M. Fecko, and A.J. Krynitsky. 1985. In Press.
Pesticides are not responsible for recent declines in native bird
populations on Guam. Micronesica.
10 Maban, A.F. 1982. The feeding ecology of the black drongo,
Dicrurus macrocercus, on Guam. M.S. Thesis. Univ. Calif., Long
Beach.
11 Seale, A. 1901. Report of a mission to Guam. Occas. Paper.
Bernice P. Bishop Mus. 1:17-128.
12 Strophet, J.J. 1946. Birds of Guam. Auk 53:539-540.
13 Marshall, J.T., Jr. 1949. The endemic avifauna of Saipan, Tinian,
Guam and Palau. The Condor 51:200-221.
14 Wiles, G.J. Unpubl. data. Div. of Aquatic and Wildl. Res., P.O.
Box 2950, Agana, Guam 96910.
15 Tomback, D. 1986. Observations on the behavior and ecology of the
Mariana crow. The Condor 88:398-401.
16 Michael, G. and R.E. Beck, Jr. Unpubl. data. Philad. Zool. Soc.,
34th and Girard Ave. Philad, PA. 19104. Div. of Aquatic and Wildl.
Res., Dept. of Agric., Govt. of Guam, P.O. Box 2950, Agana, Guam
96910.
17 Pratt, H.D., P.L. Bruner, and D.G. Berrett. 1979. America's
unknown avifauna: the birds of the Mariana Islands. Amer. Birds
33:227-235.
18 Engbring, J. and F.L. Ramsey. 1984. Distribution and abundance of
the forest birds of Guam: results of a 1981 survey. U.S. Fish and
Wildlife Service FWS/OBS-84/20. 54 pp.
19 Savidge, J.A. Unpubl. data. Div. of Aquatic and Wildl. Res.,
Dept. of Agric., Govt. of Guam, P.O. Box 2950 Agana, Guam 96910.
20 Beaty, J.J. 1967. Guam's remarkable birds. South Pacific Bull.
21:37-40.
References - 1 (DRAFT) - References
Species CROW, MARIANA
Species Id ESIS101032
Date 14 MAR 96
21 Guam Div. of Aquatic and Wildlife Resources. Field Notes. Guam
Div. of Aquatic and Wildl. Res., Dept. of Agric., Govt. of Guam,
P.O. Box 2950, Aguana, Guam 96910.
22 Pyle, Robert. 1987. Pers. comm. Bishop Museum, Honolulu, HI.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Baker, R.H. 1951. The avifauna of Micronesia, its origin,
evolution, and distribution. Univ. Kansas Publ., Mus. Nat.
Hist. 3:1-359.
02 Jenkins, J.M. 1983. The native forest birds of Guam. Ornith.
Monogr. No. 31. Am. Ornitholgists Union. Wash., D.C. 61 pp.
03 Engbring, J. and F.L. Ramsey. 1984. Distribution and abundance of
the forest birds of Guam: results of a 1981 survey. U.S. Fish and
Wildl. Serv. FWS/OBS-84/20. 54 pp.
04 Michael, G. and R.E. Beck, Jr. Unpub. data. Phila. Zool. Soc.,
34th and Girard Ave., Phila., Pa. 19104. Dept. of Agric., Div. of
Aquatic and Wildl. Res.
05 Engbring, J. and F.C. Ramsey. In Press. Pacific islands
forest bird survey. Saipan, Tinian, Aguiguan, and Rota.
U.S. Fish and Wildl. Serv., Honolulu, HI. 224 pp.
References - 2