Geographic Range
Black-backed woodpeckers are non-migratory birds native to North America and the Nearctic
Region. The northern border of where they reside stretches from Alaska to Newfoundland
and Labrador. Their range extends south through southeastern British Columbia to central
California. Moving east from British Columbia their range extends to the northeast
coast of the United States. They occupy this range throughout the year but vagrants
sometimes wander south to Nebraska, Illinois and New Jersey.
Habitat
Black-backed woodpeckers inhabit boreal and montane forests of North America where
they are able to forage for insect larvae in the trunks of coniferous trees. Black-backed
woodpeckers are attracted to fire-prone habitats and prefer to be near or within recently
burned forests. They are found at elevations of approximately 750 m.
- Habitat Regions
- temperate
- terrestrial
Physical Description
Black-backed woodpeckers are medium-sized woodpeckers that have a glossy black back
with white underparts. The throat, breast, and belly are white. The white sides and
flanks are covered in black bars and the tail is mostly black, where only the outer
feathers are white. The wings are also black with narrow white bars on them and span
12.3 to 13.4 cm. The head is glossy black and has a white stripe extending from the
nasal tufts to the nape. Individuals weigh between 61 and 88 g and measure 21.5 to
24 cm in length. These woodpeckers are one of two woodpecker species that feature
3 toes instead of the usual 4. Along with
three-toed woodpeckers
, these birds have two toes facing forwards, but only one backwards. The most likely
other species to be mistaken as black-backed woodpeckers would be
three-toed woodpeckers
. Three-toed woodpeckers have white barring on the back along with a white stripe
of varying length behind the eye. Male black-backed woodpeckers and three-toed woodpeckers
have a yellow patch of feathers on their forehead or crown.
Sexual dimorphism is present in the coloration and size of black-backed woodpeckers.
Males have a yellow forehead crown patch which is the most distinguishable characteristic
among males and females. Males have been found to be approximately 6 to 7% larger
than females. The females however, are slightly lighter in color and have shorter
bills. Juveniles are duller and have reduced or absent yellow patches.
- Other Physical Features
- endothermic
- heterothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
- male more colorful
Reproduction
Black-backed woodpeckers are monogamous. They generally only breed once per breeding
season although they have been known to re-nest if their first fails. The males attract
mates by raising the distinctive yellow crest feathers. Pair formation in this species
is not well described, but it is believed that once a male and female form a pair
they remain together year round. It also seems that once they form a pair they will
rarely interact with other black-backed woodpeckers.
- Mating System
- monogamous
Black-backed woodpeckers have a breeding distribution that corresponds to the size
and range of the boreal and mountainous coniferous forests of North America. They
excavate nest cavities in trees on average 2.23 m from the ground averaging 30 cm
deep. They prepare the nest in the months of April and May, before fertilization occurs
in June. Clutch size ranges from 2 to 6 eggs which are incubated, primarily by the
female, for 12 to 14 days. The young are altricial at birth, and will not fledge
until they are 25 days old.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- oviparous
Both male and female black-backed woodpeckers are actively involved in the development
of their young. Before fertilization occurs, they both excavate the nest which is
made up of decayed wood chips that remain in the bottom of the tree cavity. A new
nest is constructed every year and even though both parents contribute, the male seems
to do most of the work.
Both parents, though mainly the female, participate in incubating the eggs for 11
days until they hatch. After the young hatch, the parents continue to take shifts
protecting the altricial young. This period lasts up to 24 days. Both parents retrieve
food for the young from the home range surrounding the nest. They bring back both
the larval and adult stages of different insects. Both parents also provide protection
and nest sanitation. They accomplish this by brooding within the nest and by removing
the fecal sacs from the nest cavity. Fledgelings remain with the parents for a period
of time to learn foraging skills. When the young reach independence, they no longer
associate with the parents.
- Parental Investment
- altricial
- male parental care
- female parental care
-
pre-fertilization
- provisioning
-
protecting
- male
- female
-
pre-hatching/birth
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
-
pre-independence
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
Lifespan/Longevity
The lifespan of black-backed woodpeckers is undetermined, but closely related
three-toed woodpeckers
have a life expectancy of at least 6 to 8 years.
Behavior
Black-backed woodpeckers are non-migratory, but are nomadic and will move to inhabit
optimal, recently burned forests. Black-backed woodpeckers are quite secluded from
other species and only interact with others in defense of their breeding territory.
Predators as well as other cavity nesting birds are often interested in black-backed
woodpeckers' nests, and black-backed woodpeckers will defend their territory through
intimidation displays including crest-raising displays, hunched-head swinging displays,
and wing and tail spreading.
Home Range
Black-backed woodpecker home territories are approximately 2 square km around their
nesting sites. If fire does not revisit the area to replenish food resources, the
territory size will increase to incorporate more foraging sites.
Communication and Perception
Black-backed woodpeckers are quite vocal and have a very sharp and distinctively fast
call. The call is a single sharp note described as a 'kyik' sound. This call is between
mates and is used for either territorial defense or feeding young. They also use
a very unique scream-rattle-snarl call that sounds like 'wet-et-ddd-eee-yaaa' to communicate
inter- and intra-specifically. Variations occur by incorporating fast or slow drumming
in long, even rolls. This call is used in encounters with others and is associated
with a hunched-head swinging display. Young black-backed woodpeckers make a 'gurgling'
call that indicates to the parents that they are in need of food. The parents also
make this call when communicating to the young that they are about to feed them.
A visual form of communication occurs when the male raises its crest. Here he fully
erects his bright yellow crest in order to attract female mates or threaten animals
who are too close to the nest. Like all birds, black-backed woodpeckers perceive their
environment through visual, tactile, auditory and chemical stimuli.
Food Habits
Black-backed woodpeckers are insectivores that rely on the insect communities of burned
coniferous forests. They are an irruptive species that thrives in response to increased
insect populations following fire. These woodpeckers prefer to forage by peeling away
tree bark in order to find larvae and insects. As with most woodpeckers, this species
has adapted some techniques and structural features that allow for greater foraging
efficiency. They use a specific stance in order to create a greater distance between
the tree trunk and their body. This allows them to accelerate a greater mass over
a longer distance which produces a more forceful blow. Two structural adaptations
are the loss of the hallux as well as the shortening of the distal leg bones. These
give the woodpecker the ability to deliver more forceful blows, and therefore making
them more efficient at foraging for food.
Some different species of larvae that black-backed woodpeckers feed upon are:
white-spotted sawyers
, jewel or metallic wood-boring beetles (
Buprestidae
family), longhorned beetles (
Cerambycidae
family), bark-boring beetles (
Scolytidae
family), and
mountain pine beetles
. In addition to larvae, black-backed woodpeckers have also been found to eat some
plant material. They eat bark, seeds, and some fruit when there are no larvae available.
This can occur after inhabiting an area for 2 to 3 years after it has been burned.
- Primary Diet
- carnivore
- Animal Foods
- insects
- terrestrial non-insect arthropods
- Plant Foods
- wood, bark, or stems
- seeds, grains, and nuts
- fruit
Predation
Black-backed woodpeckers do not have a large number of predators as they are common
to burned forests, which are undesirable habitats to most other species. They do,
however, have certain anti-predator adaptations to better their chance of survival.
The yellow crown-patch on males serves to intimidate and ward off intruders to protect
themselves, their mates or young. Their predominately black coloration camouflages
them well within their preferred burned habitats.
Predators have been known to prey upon both nests and adult black-backed woodpeckers.
Black bears
attempt to gain access to the nest by gnawing at the entrance hole which causes the
inhabitants to scramble out towards the waiting bear. Other predators of adult woodpeckers
include birds of prey such as
Cooper's hawks
. Other predators that prey on the eggs and nestlings include
flying squirrels
and
Douglas squirrels
.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
Black-backed woodpeckers prefer to reside in recently burned forests, which are inhospitable
for many other species. These birds readily respond to increases in wood-boring beetle
populations and thrive when this food source is abundant. Black-backed woodpeckers
likely play a significant role in controlling populations of the insects they feed
upon. Black-backed woodpeckers do excavate new nest cavities each breeding season,
and thus they aid species that rely on others to create nesting sites.
- Ecosystem Impact
- creates habitat
Economic Importance for Humans: Positive
There are no known positive effects of black-backed woodpeckers on humans.
Economic Importance for Humans: Negative
There are no known adverse effects of black-backed woodpeckers on humans.
Conservation Status
The conservation of black-backed woodpeckers is not of high priority. These birds
have a large range and are estimated to have a large population size, thus the IUCN,
the United States Migratory Bird Act, United States Federal list and CITES all consider
them to be of least concern. They were also not found on COSEWIC (Committee on the
Status of Endangered Wildlife in Canada).
In the state of Michigan, black-backed woodpeckers are listed as a species of special
concern. Here they are seen as an S2 and G5 species. S2 refers to state rank of them
being vulnerable to extirpation from the state of Michigan because of rarity and other
factors which are not specified. The G5 status is the global rank where they are secure
globally but that they may becoming more rare at the perimeters of their range. Since
they are only of special concern they are just being monitored and no legal protection
is provided. However, if numbers continue to decline they would be recommended for
Threatened or Endangered Status.
Other studies have found that they can be vulnerable to local extinction because of
post-fire salvage logging as well as fire suppression as they have a specialized foraging
behavior and diet. Many efforts have been made to suppress fire in recent decades
even though it is a natural element of many ecosystems. As these birds only occupy
an area 2 to 3 years after fire, they are very vulnerable to habitat loss due to fire
suppression.
Additional Links
Contributors
Lucas Hudec (author), University of Alberta, Augustana Campus, Doris Audet (editor), University of Alberta, Augustana Campus, Rachelle Sterling (editor), Special Projects, Catherine Kent (editor), Special Projects.
- Nearctic
-
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- taiga
-
Coniferous or boreal forest, located in a band across northern North America, Europe, and Asia. This terrestrial biome also occurs at high elevations. Long, cold winters and short, wet summers. Few species of trees are present; these are primarily conifers that grow in dense stands with little undergrowth. Some deciduous trees also may be present.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- heterothermic
-
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- monogamous
-
Having one mate at a time.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- male parental care
-
parental care is carried out by males
- female parental care
-
parental care is carried out by females
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- diurnal
-
- active during the day, 2. lasting for one day.
- motile
-
having the capacity to move from one place to another.
- nomadic
-
generally wanders from place to place, usually within a well-defined range.
- sedentary
-
remains in the same area
- solitary
-
lives alone
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- cryptic
-
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
References
American Ornithologists' Union, 1983. Check-list of North American Birds . Kansas: The American Ornithologists' Union.
Bonnot, T., M. Rumble, J. Millspaugh. 2008. Nest Success of Black-backed Woodpeckers in Forests with Mountain Pine Beetle Outbreaks in the Black Hills, South Dakota. CONDOR , 110(3): 450-457.
Corace III, R., N. Lapinski, S. Sjogren. 2001. Conservation Assesment for Black-backed Woodpecker (Picoides articus). USDA Forest Service, Eastern Region: 1-21. Accessed October 11, 2010 at http://www.fs.fed.us/r1/clearwater/terra_org/wildlife_07/sensitive_species/black_backed_woodpecker/conservation_assessment.pdf .
Cornell Lab of Ornithology, 2009. "Black-backed Woodpecker" (On-line). The Cornell Lab of Ornithology All About Birds. Accessed September 20, 2010 at http://www.allaboutbirds.org/guide/Black-backed_Woodpecker/id .
Dixon, R., V. Saab. 2010. "Black-backed Woodpecker (Picoides arcticus)" (On-line). The Birds of North America Online. Accessed October 05, 2010 at http://bna.birds.cornell.edu/bna/species/509/articles/introduction .
Dudley, J., V. Saab. 2007. Home-range Size of Black-Backed Woodpeckers in Burned Forests of Southwestern Idaho. Western North American Naturalist , 67(4): 593-600.
Dunn, J., J. Alderfer, P. Lehman. 1999. Field Guide to the Birds of North America . Washington, D.C.: National Geographic Society.
Godfrey, W. 1986. The Birds of Canada . Ottawa, Ontario: National Museums of Canada.
Government of Canada, 2010. "COSEWIC (Committee on the Status of Endangered Wildlife in Canada)" (On-line). Accessed November 11, 2010 at http://www.cosewic.gc.ca/eng/sct3/index_e.cfm .
Murphy, E., W. Lehnhausen. 1998. Density and Foraging Ecology of Woodpeckers Following a Stand-Replacement Fire. The Journal of Wildlife Management , 62(4): 1359-1372.
Nappi, A., P. Drapeau. 2009. Reproductive success of the black-backed woodpecker (Picoides arcticus) in burned boreal forests: Are burns source habitats?. Biological Conservation , 142: 1381-1391.
Pierson, J., F. Allendorf, V. Saab, P. Drapeau, M. Schwartz. 2010. Do male and female black-backed woodpeckers respond differently to gaps in habitat?. EVOLUTIONARY APPLICATIONS , 3(3): 263-278.
Setterington, M., I. Thompson, W. Montevecchi. 2000. Woodpecker abundance and habitat use in mature balsam fir forests in Newfoundland. JOURNAL OF WILDLIFE MANAGEMENT , 64(2): 335-345.
Short, L. 1979. Burdens of the picid hole-excavating habitat. The Wilson Bulletin , 91(1): 16-28.
Short, L., D. Finch, P. Lehman, J. Remsen Jr.. 1983. The Audubon Society Master Guide to Birding: Gulls to Dippers . New York, NY: Alfred A. Knopf, Inc..
Spring, L. 1965. Climbing and Pecking Adaptations in Some North American Woodpeckers. The Condor , 67(6): 457-488.
Tremblay, J., J. Ibarzabal, C. Dussault, J. Savard. 2009. Habitat requirements of breeding Black-backed Woodpeckers (Picoides articus) in managed, unburned boreal forest.. Avian Conservation and Ecology , 4(1): 51-66.
Villard, P. 1994. Foraging Behaviour of Black-backed and 3-Toed Woodpeckers during spring and summer in Canadian Boreal Forest. CANADIAN JOURNAL OF ZOOLOGY , 72(11): 1957-1959.
Walters, E., E. Miller. 2001. Predation on Nesting Woodpeckers in British Columbia. Canadian Field-Naturalist , 115(3): 413-419.