(DRAFT) - Taxonomy
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
TAXONOMY
NAME - WARBLER, KIRTLAND'S
OTHER COMMON NAMES - WARBLER, KIRTLAND'S;WARBLER, PINE and JACK
ELEMENT CODE -
CATEGORY - Birds
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - AVES,
ORDER AND SUBORDER - PASSERIFORMES,
FAMILY AND SUBFAMILY - EMBERIZIDAE,
GENUS AND SUBGENUS - DENDROICA,
SPECIES AND SSP - KIRTLANDII,
SCIENTIFIC NAME - DENDROICA KIRTLANDII
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Kirtland's Warbler
Dendroica kirtlandii (Baird, 1852)
KINGDOM: Animal GROUP: Bird
PHYLUM: Chordata CLASS: Aves
ORDER: Passeriformes FAMILY: Emberizidae
Dendroica kirtlandii (Baird, 1852) was first discovered in 1851
when a spring migrant was taken near Cleveland, OH. Five more spring
migrants (four in Ohio and one in southern Michigan) were collected
before the first wintering bird was collected on January 9, 1879, on
Andros Island, Bahamas. Between 1884 and 1897 there were 71 specimens
collected throughout the Bahamas (16).
The Kirtland's warbler is sexually dimorphic. The adult male has
upper parts of bluish slate gray, streaked with black, a black mask
and white eye ring, dull yellow underparts, sides streaked with black,
and fuscous wings without bars. The adult female has upper parts of
bluish gray with fuscous streaks, pale yellow underparts, and fuscous
speckling on the breast. It is one of the largest wood warblers,
14-15 cm long, 12.2 - 16.0 grams and has a short, stout bill (01,02).
The Kirtland's warbler has previously been called the Jack pine
warbler (01). Specimens are located in the Museum of Zoology, Univ.
Taxonomy - 1 (DRAFT) - Taxonomy
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
of Michigan (16). Color illustrations appear in (02,03,04).
Taxonomy - 2 (DRAFT) - Status
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
STATUS
Coded Status
E: Federal Endangered
Federal Migratory
Non-consumptive recreational
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Kirtland's warbler (Dendroica kirtlandii) 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
U.S.A. (principally Michigan), Canada, and the West Indies: Bahama
Islands.
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.
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
Status - 1 (DRAFT) - Status
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
management, protection, and conservation of Federally
listed species into the Forest Planning process
(36 CFR 219.19 and 219.20).
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: Michigan and Wisconsin
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: (MI) Department of Natural Resources;
(WI) Department of Natural Resources.
STATE STATUTE: (MI) Act 203 of Public Acts 1974 amended by Act
401 of Public Acts 1982;
(WI) Wisconsin Statutes, Sec. 23.09, 23.11,
29.02, 29.174, and 29.415.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
The Kirtland's warbler is listed in the IUCN Red Data Book as
Endangered and in Ontario, Canada it is protected by the Ontario
Endangered Species Act. The species is also protected by law in the
Bahamas and is listed by the Convention on Nature Protection and
Wildlife Preservation in the Western Hemisphere, 1970.
ECONOMIC STATUS:
The species has no negative values to man. A positive value is
the beauty of this small bird and its allure to bird-watchers and
nature observers.
67/03/11:32 FR 04001/ - Original listing
70/08/25:35 FR 13519/13520 - Proposed rule, addition of species
70/10/13:35 FR 16047/16048 - Final rule, addition of species
73/04/25:38 FR 10208/10234 - Migratory Bird Treaty Act
75/05/13:40 FR 21499/24500 - Notice to determine Critical Habitat
79/05/21:44 FR 29566/29577 - Five year review
85/07/22:50 FR 29901/29909 - Five year review
Status - 2 HABITAT ASSOCIATIONS
HABITAT - TERRESTRIAL
TERRESTRIAL
LAND USE -
Evergreen Forest Land
COMMENTS ON HABITAT ASSOCIATIONS -
The breeding habitat of the Kirtland's warbler is very
distinctive. Nearly all nests have been found in jack pine (Pinus
banksiana) stands 5-20 feet in height and 8-21 years of age which have
resulted from forest fire. Fire also maintains the low ground cover
that conceals the nest. Nearly all pines in the stand must be small
and a tract must be at least 80 acres to attract the species. Ideal
habitat consists of homogeneous thickets of small jack pine
interspersed with many small openings (02,06).
The species' nesting habitat is also limited to a specific soil
type. Almost all nests have been found on Grayling sand soil which is
extremely pervious to water. This may be important in preventing
flooding of nests in the soil (06). The counties in Michigan
(Crawford and Oscoda) that have the largest amounts of this soil type
also have the greatest number of nesting Kirtland's warblers (06,08).
The species' habitat associations in its wintering grounds are
virtually unknown (05). An observation in the Bahamas describes a
bird in low, broad-leaved scrub (09).
Habitat Associations - 1 (DRAFT) - Food Habits
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
OMNIVORE
LIFESTAGE FOOD FOOD PART
General Forb Flowers/Fruit/Seed
General Tree-Sap
General Arthropods
General Worms
Food Habits - 1 (DRAFT) - Environment Associations
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
ENVIRONMENTAL ASSOCIATIONS
Environment Associations - 1 (DRAFT) - Life History
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
The Kirtland's warbler feeds on a variety of invertebrates.
These include; insect larvae, centipedes, worms, caterpillars, deer
and horse flies, grasshoppers, crickets, small beetles, cicadas, and
white and dusky millers (02,12). The insects are taken from the
ground, air, or pine foliage (01). The species also eats berries,
especially blueberries (01,02) and has been observed ingesting pine
pitch (12). Adults and juveniles show no differences in food types
taken. No information is available on the species feeding habits in
the wintering areas.
HOME RANGE/TERRITORY:
The Kirtland's warbler occurs in loose aggregations of "colonies"
averaging 11 males per colony (02). Males arrive in the breeding area
approximately three days prior to the females and establish
territories (02). The males defend territories ranging from 4.12 ha
to 8.48 ha (17) to as muchy as 12 ha (06,17). As the breeding
population in an area increases the territory size decreases.
Conversely as the breeding population size decreases in an area
territory size tends to increase (17). The birds sing from perches or
the ground in the early morning (01,02). No special or preferred
singing posts are used (02). The nest is usually located in the
center of a territory (02). Males almost always return to the same
territory in succeeding years although females settle in the same
territory less than 50% of the time (02). Males continue to defend
territories during incubation and brooding periods but vigor of
defense decreases (17).
PERIODICITY:
No special periodicity has been described for this species.
MIGRATION PATTERN:
The species is migratory and follows an almost direct route from
its breeding range in Michigan to the Bahamas (05). The birds leave
the breeding area in late August and early September (02). Fall
migration sightings occur mainly in Ontario, Ohio, and south Atlantic
states (02). The average spring arrival date is 12 May (02) in
central Michigan. Little detail is known about the migration rate and
stopover locations for this species, although they do pass through the
hurricane zone during hurricane season (05).
COVER/SHELTER REQUIREMENTS:
Cover and shelter requirements on the wintering grounds are
unknown.
REPRODUCTIVE SITE REQUIREMENTS:
The Kirtland's warbler requires young stands of jack pine with
small openings and ample ground cover (8 to 20 cm high) for breeding.
The peak utilization of jack pine stands occurs in stands between 11
and 17 years old in naturally burned stands, and 13 to 18 years old in
plantations. Abandonment of an area for breeding usually occurs after
Life History - 1 (DRAFT) - Life History
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
22 years in both cases (burn or plantation) (17). Blueberry and/or
grasses comprise the major ground cover around nests. The nest is
placed on the ground, often imbedded into it and near the base of a
tree (mean distance 39.4 cm) (01,02,11). The ground substrate is
almost always sand and the nest is built with dead leaves of sedges
and grasses and lined with fine vegetable fibers and sometimes deer
hair (01,02). The nest is concealed under low vegetation and is round
with an inside diameter of 50-60 mm (01).
REPRODUCTIVE CHARACTERISTICS:
The Kirtland's warbler reaches sexual maturity at about one year
(02,17). The breeding season is initiated shortly after arrival on
the breeding ground. Generally, only one nest is attempted, although
a second clutch may be produced if the first was lost to predation
(10,11,17). Second nesting attempts have been reported for older
females (two years or older) and may occur within 1 to 2 weeks after
the young have fledged from the first nest (17).
In general, the pair bond between male and female is strong
during the breeding season and only a few cases of polygamy have been
reported (17). The pair bond, however, is not often continued from
one breeding season to the next (10).
Nesting begins in late May (02) with the female responsible for
all nest building (02). A clutch of 4 or 5 (01,02) brown spotted,
whitish eggs is laid, one egg each on successive morning (02,17).
Variation in clutch size is 3 to 6 eggs (17). The female does all the
incubating although the male provides food for the female during this
time (02). The incubation period is 13-16 days and young hatch in
mid-June (01,02). Generally, all eggs hatch within 25 hours (17).
PARENTAL CARE:
The altricial young hatch in mid-June and are fed by both adults
(02). Young weigh about 1.2 to 1.8 grams each. Brooding decreases
throughout the nestling period except the female (and occasionally the
male) may periodically brood the nestling in cold or rainy weather
regardless of nestling age (17). Females search for food within 91 m
to 122 m of the nest (17). Adults feed on insects which are brought
back to the nestlings. During the early nestling period, when the
female is primarily brooding, the male provides food for the nestlings
and sometimes provides food for the mate. As the nestlings become
older feeding is shared more by both sexes. In the absence of the
male, females will chase away other small birds (sparrows and
chickadees) or neighboring male warblers that come near the nest. The
female will attempt to distract larger birds (blue jays) or mammals
(ground squirrels) away from the nest when they approach within one
meter (17). Young leave the nest at 9 days usually by flight. At
this time each parent takes a portion of the brood and cares for it
exclusively (02). At 23-29 days of age the young undergo their first
post-juvenile molt (02). However, fledglings are fed by parents until
they are about 35 days old (range 26 to 41 days) (17). Females that
renest after a successful first nest have the major responsibility for
the second nest while the males care for the fledglings at the first
nest (17).
Life History - 2 (DRAFT) - Life History
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
POPULATION BIOLOGY:
The Kirtland's warbler has a life expectancy of about 2 years
(02) to 4 years (17) which is longer than many songbirds (07). The
oldest individual known was nine years (10). The survival rate for
the first year is 60% with a 50% survival rate needed to maintain a
stable population (02).
One major limiting factor to the population, cowbird parasitism,
has been controlled. This has increased the fledgling rate from 1.9
to 3.2 in recent years (11). However, the breeding population has not
increased during periods of this control (13). This suggests that
other factors of the species biology are limiting its population
(e.g., habitat availability on breeding and wintering grounds,
post-fledging mortality, and yearling dispersal) (14).
SPECIES INTERRELATIONSHIPS:
The brown-headed cowbird (Molothrus ater) parasitizes the nests
of the Kirtland's warbler (02). The cowbird lays eggs in the
warbler's nest and often removes the warbler's eggs. Cowbird young
hatch before young warblers, making the cowbird a very succesful
parasite (15). Known predators of Kirtland's warbler nestlings
include: blue jays, thirteen-lined ground squirrels and garter
snakes. Other possible predators include: skunks, raccoons and crows
(17). The extent of predation is unknown.
OTHER LIFE HISTORY DESCRIPTORS:
None.
Life History - 3 (DRAFT) - Management Practices
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Suppressing wildfire
Beneficial Prescribed/controlled burning of habitat
Beneficial Selective Thinning
Beneficial Timber Harvesting
Beneficial Controlling/Restricting Off-Road Vehicles
Beneficial Restricting/regulating human disturbance of populations
Beneficial Land Acquisition
Beneficial Reforestation
Beneficial Maintaining Early Stages of Succession
Beneficial Controlling/Removing Native Vegetation
Beneficial Stocking captive-reared wild-strain animals
Beneficial Transplanting wild animals
Beneficial Transplanting Wild Eggs/Wild Seeds
Beneficial Controlling/Removing Invertebrates
Beneficial Controlling/Removing Native Vertebrates
Adverse Low Gene Pool
Existing Low Gene Pool
Adverse Parasites
Existing Parasites
Adverse Competition
Existing Competition
Adverse Vegetation Composition Changes
Existing Vegetation Composition Changes
Adverse Suppressing wildfire
Existing Suppressing wildfire
Adverse Forest Alteration
Existing Forest Alteration
COMMENTS ON MANAGEMENT PRACTICES -
The major causes of this species' precarious position are its
small population size (05), restricted geographic range, and extremely
narrow habitat requirements (01). Prevention of fire in modern times
has greatly reduced the total acreage burned and also the size of
individual burns. This, along with forest management practices that
encourage conversion of jack pine to red pine or hardwoods, has been
detrimental to the Kirtland's warbler populations (06). Only 4000 to
5000 acres are presently suitable for breeding compared to 10,000 to
15,000 acres available in the 1950's and 1960's (06).
Another limiting factor is nest parasitism of the brown-headed
cowbird (Molothrus ater). Apparently the Kirtland's warbler has not
developed defenses against this nest parasite as other songbirds have
(07).
Another possible limiting factor, yet unidentified, may occur on
the wintering grounds or during migration (06). Whether the species
has high migration mortalities or whether habitat or food is limited
on the wintering grounds has not been addressed (05).
Management Practices - 1 (DRAFT) - Management Practices
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1985. Revised Kirtland's Warbler
Recovery Plan. U.S. Fish and Wildlife Service, Twin Cities, MN.
45 pp.
The primary objective of the Recovery Plan is to reestablish a
self-sustaining wild Kirtland's warbler population throughout its
known former range at a minimum level of 1000 pairs. This will be
accomplished by:
1. Maintain and develop suitable nesting habitat for the Kirtland's
warbler throughout its former range. Utilize fire control, prescribed
burning, insect and disease control, habitat rehabilitation, hand and
mechanical planting of jack pine (Pinus banksiana) logging (commercial
and non-commercial) and land acquisition.
2. Protect the species on its wintering grounds and along the
migration route.
3. Reduce key factors adversely affecting reproduction and survival
of the species, which includes limiting human access, restricting
off-road vehicle use, and controlling avian predators and parasites
such as cowbirds and blue jays.
4. Monitor breeding populations of the species to evaluate responses
to management practices and environmental changes.
5. Reintroduce Kirtland's warbler into areas in the upper peninsula
of Michigan or in other states in an attempt to establish independent,
self-sufficient populations. Utilize wild or captive bred individuals
or eggs.
Management Practices - 2 (DRAFT) - References
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 National Fish and Wildlife Laboratory. 1980. Selected vertebrate
endangered species of the seacoast of the United
States - Kirtland's warbler. FWS/OBS-80/01.21.
02 Mayfield, H.F. 1960. The Kirtland's Warbler. Cranbrook Inst.
Sci., Bloomfield Hills, MI.
03 Peterson, R.C. 1980. A Field Guide to the Birds East of the
Rockies, 4th ed. Houghton Mifflin, Boston.
04 Robbins, S.C., B. Brunn, and H.S. Zim. 1966. A Guide to Field
Identification: Birds of North America. Golden Press, New York.
05 Mayfield, H.F. 1975. The numbers of Kirtland's warblers.
Jack-pine Warbler 53:39-66.
06 U.S. Fish and Wildlife Service. 1976. Kirtland's Warbler Recovery
Plan. U.S. Fish and Wildlife Service.
07 Walkinshaw, L.H. 1972. Kirtland's warbler endangered. Amer.
Birds 26:3-9.
08 Zimmerman, D.A. 1956. Jack pine association in the lower
peninsula of Michigan: Its structure and composition. Ph.D.
Diss., Univ. Mich.
09 Radabaugh, B.E. 1974. Kirtland's warbler and its Bahama wintering
grounds. Wilson Bull. 75:208-215.
10 Berger, A.J. and B.E. Radabough. 1968. Returns of Kirtland's
warbler to the breeding grounds. Bird-banding 39:161-186.
11 Orr, C.D. 1975. 1974 breeding success of the Kirtland's warbler.
Jack-pine Warbler 53:59=66.
12 Leopold, N.F., Jr. 1924. The Kirtland's warbler in its summer
home. Auk 16:44-58.
13 Ryel, L.A. 1982. The Kirtland's warbler in 1982. Mich. Dept.
Nat. Resour, Wildlife Div. Rept. No.2921.
14 Ryel, L.A. 1982. Population change in the Kirtland's warbler.
Jack-pine Warbler 59:76-91.
15 Kelly, S.T. and M.E. DeCapita. 1981. Cowbird control and its
effect on Kirtland's warbler reproductive success. Wilson Bull.
94:363-365.
16 U.S. Forest Service and Michigan Dept. of Natural Resources. 1979.
Management Plan fot the Kirtland's Warbler Habitat. Vol. I and II.
17 Walkinshaw, L.H. 1983. Kirtland's Warbler: The Natural History
of an Endangered Species. Cranbrook Inst. of Sci., Bloomfield
Hills, MI. 207 pp.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Ryel, L.A. 1982. The Kirtland's warbler in 1982. Mich. Dept.
Nat. Resour, Wildlife Div. Rept. No.2921.
02 Mayfield, H.F. 1975. The numbers of Kirtland's warblers.
Jack-pine Warbler 53:39-66.
03 Radabaugh, B.E. 1974. Kirtland's warbler and its Bahama wintering
grounds. Wilson Bull. 75:208-215.
04 Mayfield, H.F. 1960. The Kirtland's Warbler. Cranbrook Inst.
References - 1 (DRAFT) - References
Species WARBLER, KIRTLAND'S
Species Id ESIS103001
Date 14 MAR 96
Sci., Bloomfield Hills, MI.
05 U.S. Forest Service and Michigan Dept. of Natural Resources. 1979.
Management Plan fot the Kirtland's Warbler Habitat. Vol. I and II.
06 Walkinshaw, L.H. 1983. Kirtland's Warbler: The Natural History
of an Endangered Species. Cranbrook Inst. of Sci., Bloomfield
Hills, MI. 207 pp.
07 U.S. Fish and Wildlife Service. 1985. Kirtland's warbler midyear
research progress report. Office of Endangered Species,
Washington, D.C.
08 Aird, P. 1985. Personal communication. Faculty of Forestry,
Univ. of Toronto, Toronto, Ontario. M5 S 1A1.
09 Ryel, L.A. 1983. Status of the Kirtland's warbler. Mich. Dept.
of Nat. Res., Wildlife Division. Rept. No. 2951.
10 U.S. Fish and Wildlife Service. 1986. Regional Briefs.
Endangered Species Technical Bulletin 11(3).
References - 2