(DRAFT) - Taxonomy
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
TAXONOMY
NAME - HAWK, HAWAIIAN
OTHER COMMON NAMES - HAWK and HAWAIIAN; 'IO;IO
ELEMENT CODE -
CATEGORY - Birds
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - AVES,
ORDER AND SUBORDER - FALCONIFORMES,
FAMILY AND SUBFAMILY - ACCIPITRIDAE,
GENUS AND SUBGENUS - BUTEO,
SPECIES AND SSP - SOLITARIUS,
SCIENTIFIC NAME - BUTEO SOLITARIUS
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Hawaiian Hawk
Buteo solitarius Peale, 1848
KINGDOM: Animal GROUP: Bird
PHYLUM: Chordata CLASS: Aves
ORDER: Falconiformes FAMILY: Accipitridae
The Hawaiian hawk is a small, broad-winged buteonine, and as with
most other birds of prey, female hawks are larger than males. The
average weight of female hawks is 605 g, average male weight is 441 g.
The species has distinct melanistic and light color phases as well as
intermediate plumages and much individual variation. Dark phase hawks
are uniformly dark above and below, but immature birds generally have
more brown, buff, and whitish markings on both ventral and dorsal
sides. Adult light phase hawks are distinguished by light-colored
heads and very light breasts with few dark flecks on the sides.
Detailed descriptions of these various plumages and other
characteristics are found in Griffin (01). The species is commonly
referred to by its Hawaiian name, 'io (or io).
When Captain Cook landed at the Hawaiian Islands on his last
voyage, "Brown Hawks or Kites" were observed, but apparently no
specimen was taken (02). Thus, the species was not brought to the
Taxonomy - 1 (DRAFT) - Taxonomy
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
attention of the scientific world until Peale (03) returned from the
U.S. Exploring Expedition. Because most Hawaii Island specimens were
lost in a shipwreck, Peale described the species (Buteo solitarius)
from a specimen taken near Kealakekua Bay, Hawai'i by the Rev. Forbes.
Cassin (04) later mistakenly referred to this same specimen as Pandion
solitarius, but the buteonine character of the hawk was reconfirmed by
Baird et al. (05) and Gurney (06,07).
Much confusion arose over an early specimen of B. solitarius
taken in California, described by Ridgway (08) as Onychotes gruberi.
This specimen was a different color phase then that described by
Peale, and at the time was considered a newly discovered species from
California. Subsequently, Ridgway (09) determined the identity of O.
gruberi with B. solitarius, and it was believed that the supposed
California collection site was in error. However, Henshaw (10,11)
offered a plausible explanation for the occurrence of the species in
California.
Since Peale first described the species, there has been much
confusion concerning the plumage patterns of the species. Although
Ridgway (08) mistakenly identified the specimen of Onychotes gruberi,
a supposed new Californian species, he was the first to recognize the
2 color phases of the species. Nevertheless, he erred in describing
the light-headed immature light phase plumage as the adult plumage.
Gurney (07) described 3 distinct plumage phases of hawks. While he
correctly identified both adult light and dark color phases, he
included the immature plumage of light-phased hawks as a third
distinct adult plumage. Henshaw (12,13) recognized 2 color phases,
and provided detailed descriptions of immature and adult plumages of
each. Unfortunately, he misunderstood the distinction between
immature and adult light phase plumages, and described adults as
having light-colored heads and immatures as dark-headed. Although
Perkins (14) originally supposed that light phase adult hawks were
dark headed, he deferred to Henshaw's plumage classifications. Most
subsequent published descriptions of hawk plumages, including field
guides, have followed Henshaw's erroneous classifications, including
Munro (15), Peterson (16), Berger (17), and Shallenberger (18).
Although Brown and Amadon (19) also followed Henshaw's descriptions,
their illustrations of hawks (plate 99, p.593) correctly displays
appropriate plumages for immature and adult light phase hawks. Banko
(20) provided collection histories and deposition locations of 99
hawk specimens in museum collections.
Taxonomy - 2 (DRAFT) - Status
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
STATUS
Coded Status
E: Federal Endangered
Federal Migratory
Non-consumptive recreational
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Hawaiian hawk, or 'io, (Buteo solitarius) 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 States of Hawaii.
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.
The species 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.
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
Status - 1 (DRAFT) - Status
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
(36 CFR 2.1, 2.2, and 2.3).
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: Hawai'i
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: Department of Land and Natural Resources,
Division of Forestry.
STATE STATUTE: Hawai'i Revised Statutes, Chapter 195D.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
The 'io is listed as rare in the IUCN Red Data Book. It is not
listed by CITES, however, this species is listed by the Convention on
Nature Protection and Wildlife Preservation in the Western
Hemisphere, 1970.
ECONOMIC STATUSES:
This species is one of the rare birds sought on Hawai'i by bird
watchers.
67/03/11:32 FR 04001/ - Original listing
69/03/08:34 FR 05034/05035 - Republished list
70/08/25:35 FR 13519/13520 - Proposed relisting
70/10/13:35 FR 16047/16048 - Final ruling on previous list
85/07/22:50 FR 29901/29909 - Five year review
85/04/05:50 FR 13707/13722 - Revised list of Migratory Birds
Status - 2 HABITAT ASSOCIATIONS
HABITAT - TERRESTRIAL
TERRESTRIAL
LAND USE -
Cropland and Pasture
Orchards, Groves, Vineyards, Nurseries,
Mixed Rangeland
Evergreen Forest Land
COMMENTS ON HABITAT ASSOCIATIONS -
The species utilizes a wide array of both exotic and native
habitats, including: closed 'ohi'a rainforest, mixed open forests
with 'ohi'a and koa, open koa forests with and without mamane, open
mamane-naio forest with subalpine shrubs, open and closed guava
forests, eucalyptus stands, Casurina stands, papaya and macademia nut
orchards, and pastureland with scattered tall 'ohi'a and/or koa trees
(01).
Of 28 hawk nest sites found in 1980-1981, 15 were in 'ohi'a or
'ohi'a/koa forests, 5 were in pasturelands with scattered large
'ohi'a/koa trees, and 8 were in areas dominated with exotic vegetation
(01).
Hawks show a remarkable ability to utilize highly modified
habitats such as pastureland and some agricultural areas which have
trees for nesting and perching. Replacement of some forest by exotic
trees or agricultural crops such as macademia nuts or papayas has
produced habitat with a prey base (i.e., rats) perhaps even larger
than pristine forests. However, many of these modified habitats
probably do not contain adequate perching and nesting sites (22).
Habitat Associations - 1 (DRAFT) - Food Habits
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
LIFESTAGE FOOD FOOD PART
General Arthropods
General Crustaceans
General Amphibia
General Carrion
General Aves
General Mammalia
Food Habits - 1 (DRAFT) - Environment Associations
Species HAWK, HAWAIIAN
Species Id ESIS101007
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 HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
Because the hoary bat (Lasiurus cinereus) was the only land
mammal native to Hawai'i, birds were probably the primary prey
available to Hawaiian hawks when they colonized the archipelago.
Absence of native land reptiles, amphibians, and freshwater fish
further restricted the potential diet of hawks. However, with the
arrival of Polynesian and European man, many other potential hawk prey
were introduced. Today, hawks utilize a wide variety of introduced
and native prey items, and they are very versatile and adaptable in
their feeding habits (01).
The known diet of the hawk includes 23 species of birds, 6
species of mammals, 7 species of insects/spiders, 1 species of
crustacean, and 1 species of amphibian (01).
The composition of the diet varied much between habitat types
where hawks nested. At low elevation nests located in forested and
agricultural areas, avian prey comprised a larger proportion of the
diet (measured as number of prey items delivered; mean=64%) than did
mammal prey. Mammals comprised a larger proportion at mid-elevation
nests (mean=84%) located in pasturelands. These differences in
proportions of avian and mammalian prey among nests may reflect the
relatively higher densities of mammals (especially mice) in
pastureland habitats at mid-elevations (01).
There were also differences between type of prey brought by male
and female hawks at low elevation nests in forested and agricultural
areas. Males at these nests consistently delivered a higher
proportion of avian prey than females. However, no differences in
selection of prey type were found between sexes at mid-elevation
pastureland nests where both sexes preyed primarily on rodents (01).
HOME RANGE/TERRITORY:
Hawks have strong territory and mate fidelity. Most occupy the
same territories and pair with the same mates in subsequent years.
Hawks exhibit both inter- and intra-specific agonistic behavior and
nest defense. Intruders are chased from territories by resident
hawks, and breeding birds are very aggressive towards humans near
their nests. Home ranges of hawks averaged 447 ha, ranging from 48 to
642 ha. Average home range sizes were similar in open (459 ha) and
closed (526 ha) 'ohi'a forests and pasturelands (484 ha). In
contrast, the range size of a male hawk in an agricultural area of
papaya and guava orchards was only 48 ha. Range sizes of juvenile
hawks gradually increased during the months after fledging. None
moved further than 0.63 km from nests during the first 2 months after
fledging. Juveniles moved out of their parents' home ranges in the
6th month after fledging (01).
PERIODICITY:
The species is diurnal (01).
MIGRATION PATTERNS:
The Hawaiian hawk is non-migratory (01).
Life History - 1 (DRAFT) - Life History
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
COVER/SHELTER REQUIREMENTS:
The species utilizes a wide variety of both exotic and native
habitats. However, the extensive clearing of forests for sugarcane
production, pasture, and other agricultural uses has undoubtedly
decreased hawk nesting habitat. Thus, the continued existence or
improvement of forest ecosystems, including native upper montane
forests and native and exotic lowland forests, seems important for the
maintenance of the hawk population (22).
REPRODUCTIVE SITE REQUIREMENTS:
Hawks nest in a wide variety of habitats, ranging from lowland
agricultural areas and exotic forests to mid-elevation pasturelands
and native rain forests. Nests are found at elevations of 30 m above
sea level to over 1700 m. Of 28 nest sites, 15 were in 'ohi'a or
'ohi'a/koa forests, 5 were in pasturelands, and 8 were in areas
dominated by exotic vegetation. There is a wide variety of understory
types associated with these nests sites. Twenty-eight hawk nests were
found in 6 different tree species. Nests are in short (10 m) and tall
(24 m) trees and are constructed anywhere from 3.5 to 18 m from the
ground. Although nest trees were fairly large (mean dbh=50.3 cm),
hawks selected trees as small as 10.2 cm dbh. Of 24 nests, 9 (32%)
were on top of birds'-nest ferns (Asplenium nidus), 5 in trunk
crotches, 3 each on large and medium-sized branches, and 4 on small
branches at their juncture with the trunk (01).
REPRODUCTIVE CHARACTERISTICS:
Hawks are monogamous. Courtship and territorial display flights
by hawks consist of mutual soaring, diving, and foot-touching;
undulating displays; and "pot-hooks". The entire breeding season (egg
laying to fledging) spans about 154 days with the peaks of laying in
late April and early May, of hatching from late May to late June, and
of fledging in mid August. Hawks have a regular breeding season
despite great differences in annual rainfall and much variability in
rainfall between island localities. All hawk pairs do not breed every
year, and there is a tendency for pairs which successfully bred in 1
year to skip breeding the next year. Although the reported clutch
size for hawks is 2-3 eggs, clutch size was 1 at 10 nests where clutch
size was accurately determined. Furthermore, in 30 nesting attempts
during 3 nesting seasons never was there any indication that more than
1 egg was laid. Incubation lasted approximately 38 days. The
nestling period extended for 59 to 63 days. Adult hawks delivered
prey to juveniles for 25-37 weeks after fledging (mean=30.2 weeks)
(01).
PARENTAL CARE:
Hawks exhibit both inter- and intra-specific agonistic behavior
and nest defense. Intruders are chased from territories by resident
hawks, and breeding birds are very aggressive towards humans near
their nests. Nest building occurs long before egg laying and
continues into the nestling period. Prior to hatching, both sexes
bring material to nests with females and males making 64% and 36% of
trips, respectively. Nest building occurs throughout the day with
peak activity between 0700 and 1100 hours. Hawks line nest cups with
Life History - 2 (DRAFT) - Life History
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
greenery. Male hawks assist females with incubation, and they provide
much of the food at nests through week 4 of the nestling period.
Females do all the feeding and brooding of young, and by week 5
females begin leaving young unattended for increasingly longer
periods. By fledging (week 9), nest attendance by females is very
short. Incubation lasted approximately 38 days. The nestling period
extended for 59 to 63 days. Adult hawks delivered prey to juveniles
25-37 weeks after fledging (mean=30.2 weeks) (01).
POPULATION BIOLOGY:
The average hatching success for the species was 88%, average
nestling success was 68%. No differences in hawk nest success
occurred in habitats dominated by native vegetation (77%) versus those
with exotic (65%). However, extensive modification of native
Hawaiian forests has undoubtedly reduced the quantity of hawk nesting
habitat. Avian malaria was not affecting chick survival and nest
success at low elevations (< 1,500 m) where mosquitoes were abundant,
versus mid-elevation nest sites where mosquito numbers were low.
Given the insular range of this endemic species, the hawk population
will always be relatively small. However, considering the current
size and distribution of the hawk population, the species' high
breeding success, the relatively low levels of predation and the
absence of environmental contaminants overtly affecting the hawk, the
population appears to be in a more secure condition than previously
thought. This information indicates that reclassification to
threatened status may be warranted. However, continued monitoring and
the implementation of other conservation recommendations previously
outlined must be pursued before complete delisting should be
considered (01).
SPECIES INTERRELATIONSHIPS:
None.
OTHER LIFE HISTORY DESCRIPTORS:
None.
Life History - 3 (DRAFT) - Management Practices
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Restricting/regulating human use of habitats
Beneficial Land Acquisition
Beneficial Controlling/Restricting Pesticide Use
Beneficial Controlling/Restricting Agricultural Practice
Beneficial Reforestation
Beneficial Restricting Timber Harvest
Beneficial Rehabilitating Individuals
Beneficial Restricting Poaching
Adverse Harassment/Vandalism/Indiscriminate Killing
Existing Harassment/Vandalism/Indiscriminate Killing
Adverse Grazing
Existing Grazing
Adverse
Existing
Adverse Forest Alteration
Existing Forest Alteration
Adverse Harvesting
Existing Harvesting
COMMENTS ON MANAGEMENT PRACTICES -
Hawai'i's forests have been drastically reduced, and most lowland
forests were already modified before European contact (21). Today,
most lowland forests have been converted to agriculture, grazing or
urban uses, and introduced plants now dominate much of the island
below 800 m elevation. Whereas habitat destruction and alteration
have probably been the most significant factors affecting the hawk
population, it is difficult to assess the extent and degree of their
effect because of the scarcity of historical information on the
population size of the species. Assessment is further complicated
because hawks use many of the highly modified habitats (01). Shooting
and harassment of nesting birds by man may be the most significant
factors directly affecting the species today; however, the current
extent of losses from these human-related factors is unknown (01).
The hawk does not appear to be very vulnerable to the introduced
diseases of avian malaria and avian pox (01). Neither native nor
introduced predators appear to pose a major threat to the species
(01).
Future threats to the species include: continuing conversion of
mid-elevation forests to pasture, and urban development, particularly
in forested regions around Hilo. While organochlorine compounds and
rodenticides do not appear to be strong factors affecting the hawk
population, changes in pesticide use in the future need to be
evaluated (01).
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1984. The Hawaiian Hawk Recovery
Management Practices - 1 (DRAFT) - Management Practices
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
Plan. U.S. Fish and Wildlife Service, Portland, OR. 48 pp.
The 'io, Hawaiian hawk, survives in good numbers in suitable
habitat over its entire range on the Island of Hawai'i. This species
has resisted the many threats (particularly disease and predation)
that have decimated other native birds. Though the recovery plan
proposes numerous actions to improve the status of the hawk, the plan
emphasizes that dramatic increases over the present population are not
expected. Rather, the plan proposes to prevent a down-turn in the
hawk's status in the face of expanding economic development and
related human disturbance. Stated recovery actions include:
1. Surveys of 'io population size and distribution.
2. Extensive studies of life history parameters and population
ecology of the 'io.
3. Population monitoring.
4. Studies of human impact on the 'io population.
5. Protect nest sites primarily by controlling the use and
development (i.e., agricultural uses and practices) of
nesting areas (e.g., vegetational buffer zones should be
delineated around 'io nests, zoning laws enforced, etc.) and
by educating landowners of 'io habitats.
6. Minimizing identified detrimental factors, by promoting
conservation of forest habitat, revegetation of pasturelands
where feasible, law enforcement against taking of 'io, and
development of a public information program.
7. Evaluation of all changes in type and use of pesticides
should be conducted.
The plan proposes that the 'io may be down-listed to threatened status
once a stable population of 2,000 birds is attained.
Ongoing or completed recovery actions include:
1. Surveys of 'io population size and distribution conducted by
the U.S. Fish and Wildlife Service (USFWS) (completed).
2. Intensive field studies of 'io biology by the Missouri
Cooperative Wildlife Research Unit (completed).
3. Securing of 'io habitat through forest preservation
(ongoing).
Though no habitat has been secured solely for the 'io, the
following projects will protect segments of the 'io population:
1. Ongoing acquisition of Hakalau National Wildlife Refuge by
the USFWS.
2. Proposed expansion of the Hawaii Volcanoes National Park.
3. Designation of six Natural Reserve Areas by the State of
Hawai'i, totalling roughly 78,000 acres. The Pohakuloa
Endangered Species Propagation Facility treats and
rehabilitates injured 'io.
Management Practices - 2 (DRAFT) - References
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Griffin, C.R. 1985. Biology of the Hawaiian hawk (Buteo
solitarius). Ph.D. diss., Univ. of Missouri. 225 pp.
02 Medway, D.G. 1981. The contribution of Cook's third voyage to the
ornithology of the Hawaiian Islands. Pacific Sci. 33:105-175.
03 Peale, T.R. 1848. Mammalia and ornithology. In: U.S. Exploring
Expedition during the years 1838, 1839, 1840, 1841, 1842. Vol.
VIII. C. Sherman, Philadelphia, PA.
04 Cassin, J. 1858. United States Exploring Expedition, 1838-1842.
Mammalia and Ornithology. Vol. 8. 17-338 pp. C. Sherman,
Philadelphia, PA.
05 Baird, S.F., T.M. Brewer, and R. Ridgway. 1874. History of North
American land birds, Vol. 3. 255 pp.
06 Gurney, J.H. 1876. XXI - Notes on a "Catalogue of the Accipitres
in the British Museum" by R. Bowler Sharpe (1874). Ibis
6(3):230-243.
07 Gurney, J.H. 1891. Note on buteo (Onychotes) solitatius. Ibis
3(6):21-24.
08 Ridgway, R. 1875. Notice of a very rare hawk. Rod and Gun
6(5):79.
09 Ridgway, R. 1885. On Onychotes gruberi. Proc. U.S. Nat. Mus.
1885:36-38.
10 Henshaw, H.W. 1901. Birds of prey as ocean waifs. Auk
18(2):162-165.
11 Henshaw, H.W. 1902. Buteo solitarius off the coast of Hawaii.
Auk 19(2):197-198.
12 Henshaw, H.w. 1902. Birds of the Hawaiian Islands, being a
complete list of the birds of the Hawaiian possessions with notes
on their habits. Thos. G. Thrum, Honolulu. 146 pp.
13 Henshaw, H.W. 1902. On the various plumages of Buteo solitarius.
Ibis 2(25):386-392.
14 Perkins, R.C.L. 1903. Vertebrata (aves). Pages 368-465. IN:
Fauna Hawaiiensis, Vol. 1, Part 6. D. Sharp, ed. The University
Press, Cambridge.
15 Munro, G.C. 1944. Birds of Hawaii. Tongg Publ. Co., Honolulu.
192 pp.
16 Peterson, R.T. 1969. A field guide to western birds. Houghton
Mifflin Co., Boston. 366 pp.
17 Berger, A.J. 1981. Hawaiian birdlife. Univ. Press of Hawaii,
Honolulu. 26 pp.
18 Shallenberger, R.J. 1981. Hawaii's birds. Hawaii Audubon Soc.,
Honolulu, HI. 96 pp.
19 Brown, L.H. and D. Amadon. 1968. Eagles, hawks and falcons of the
world. Contry Life Books, London. 945 pp.
20 Banko, W.E. 1979. History of endemic Hawaiian birds. Specimens
in museum collections. CPSU/UH Avain History Report 2. (Dept. of
Botany, Univ. of Hawai'i). 80 pp.
21 Kirch, P.V. 1982. The impact of prehistoric Polynesians on the
Hawaiian ecosystem. Pac. Sci. 36(1):1-14.
22 U.S. Fish and Wildlife Service. 1984. Hawaiian Hawk Recovery
References - 1 (DRAFT) - References
Species HAWK, HAWAIIAN
Species Id ESIS101007
Date 14 MAR 96
Plan. U.S. Fish and Wildlife Service, Honolulu. 48 pp.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Griffin, C.R. 1985. Biology of the Hawaiian hawk (Buteo
solitarius). Ph.D. diss., Univ. of Missouri. 225 pp.
02 Scott, J.M., S. Mountainspring, F.L. Ramsey, and C.B. Kepler.
1986. Forest bird communities in the Hawaiian Islands: Their
dynamics, ecology and conservation. Studies in Avain Biol. 9.
03 Banko, W.E. 1980. History of endemic Hawaiian birds. Part I.
Population histories -- species accounts. Forest birds: Hawaiian
hawk ('io). CPSU/UH Avain History Report 6A. (Dept. of Botany,
Univ. of Hawai'i).
04 Scott, J.M. 1985. Unpublished data. U.S. Fish and Wildlife
Service, Condor Recovery Project, 2291-A Portola Rd., Ventura, CA
93003.
05 Shallenberger, R.J. 1977. Bird and mammal survey of Army lands in
Hawaii, Part III (13 sites). Ahuimanu Productions (Oahu).
06 Griffin, C.R. 1985. Unpublished data. Univ. of Massachusetts,
Dept. of Forestry and Wildlife Management, Holdsworth Hall,
Amherst, MA 01003.
07 Morrison, G.T. 1969. Hawaiian hawk. 'Elepaio 29(9):75-89.
References - 2