Geographic Range
Bearded wood-partridges are found in the Neotropical region, in Mexico. They make
their home mainly along the coast of the Gulf of Mexico, in the Sierra Madre Oriental
mountain range and the Sierra Madre de Oaxaca pine-oak forests. There are significant
populations of bearded wood-partridges in Veracruz, as well as in Quetaro, Puebla,
Hidalgo, and San Luis Potosi.
- Biogeographic Regions
- neotropical
Habitat
Bearded wood-partridges make their homes in dense and humid pine-oak, cloud, and second-growth
forests that are often quite secluded. They have also been known to live in shade
coffee plantations and other agricultural habitats. These birds are riparian and will
often stay close to small rivers and streams.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- forest
- rainforest
- Other Habitat Features
- agricultural
- riparian
Physical Description
Bearded wood-partridges are one of the larger species of partridge. Overall, they
are a brownish reddish color with wings that are darker and mottled with black and
tan. They have a gray-blue head and neck, with a small, brown crest. They have other
gray streaks around the mantle and chest. The underside is a light brown, and they
have distinctive red legs, bill, and eye-ring. They are usually between 400 and 460
g in weight and 22 to 36 cm in length. The sexes are alike in appearance, but males
are larger.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
- male larger
Reproduction
Males use vocal calls in courtship. Although specific information on the mating system
for this species could not be found, close relatives of bearded wood-partridges are
monogamous. Once a male and female pair up, they behave aggressively towards other
males and females.
- Mating System
- monogamous
Little is currently known about the reproductive behavior of bearded wood-partridges.
Captive birds often have broods of 5 chicks, construct nests in shallow holes in the
ground and line them with palm leaves. Partridges in general usually have only one
brood per year. Bearded wood-partridges breed between April and June. Close relatives
of bearded wood-partridges incubate eggs for approximately 18 days. The chicks are
precocial, develop rapidly and are often capable of short flight within 7 to 14 days.
The nest is not reused. Time to independence is not known but individuals reach sexual
maturity between one and two years.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- oviparous
Bearded wood-partridges are generally monogamous and both parents play a role in taking
care of the offspring. The female does most of the incubating but occasionally the
male will help incubate the eggs. The young are precocial and begin foraging with
their parents soon after hatching. The mother and father work together to defend their
territory and to provide the chicks with food.
- Parental Investment
- precocial
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- male
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
Lifespan/Longevity
Nothing is known for certain about the life-span of bearded wood-partridges but partridges
in general have a life-span of between 1 and 5 years. Close relatives of bearded wood-partridges
have an average life-span of around 3 years.
Behavior
Bearded wood-partridges are a social species and form groups or "convoys." They spend
most of their time on the ground in thickets and roost in small trees or tall shrubs.
They are wary and are easily frightened; many locals hear the birds call but never
see them.
- Key Behaviors
- terricolous
- flies
- diurnal
- motile
- nomadic
- territorial
- social
Home Range
Because these birds are generally monogamous, once a bond pair forms, the two birds
defend a "mobile territory." This is a relatively small area that both the male and
female will defend from others. This territory moves with the birds as they travel.
Communication and Perception
Bearded wood-partridges are known locally for their chorus calls. These birds usually
call at dawn or dusk, and choruses last 15 to 20 minutes; it is considered a way for
the birds to announce their location to each other and to other flocks.
Calls of males are a series of loud, shrill whistles, often with three or four syllables;
females have a softer call with more syllables.
- Other Communication Modes
- choruses
Food Habits
Little is known about the feeding habits of bearded wood-partridges but, like their
close relatives, they eat fruits, nuts, berries, vegetation and small invertebrates.
They scratch the leaf litter and ground in search of food. Bearded wood-partridges
often eat crops such as beans and corn near their homes. In captivity bearded wood-partridges
have been observed to eat beans, corns, grapes, and bananas.
- Primary Diet
- omnivore
- Animal Foods
- insects
- Plant Foods
- seeds, grains, and nuts
- fruit
Predation
Bearded wood-partridges have been hunted by humans. Because they often live near or
even within agricultural fields or crops, the locals look at them as pests and thus
take measures against them.
No other specific natural predators are known, but it is likely that many small to
medium-sized predators, including
cat
species and
birds of prey
may take these partridges. Their cryptic coloration helps them to blend into the
undergrowth in habitats they occupy and their flocking behavior means that more eyes
are watching for predators at any given time.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
Bearded wood-partridges are mainly primary consumers, feeding on fruits, nuts and
seeds. As a result, they aid plants in reproduction by dispersing some plant seeds.
These birds also dig in the soil for invertebrates and other food, which helps to
break up the soil and allow more water and air to enter.
- Ecosystem Impact
- disperses seeds
- soil aeration
Economic Importance for Humans: Positive
Humans hunt bearded wood-partridges for sport and for food, but these birds are not
otherwise of great economic importance to humans.
- Positive Impacts
- food
Economic Importance for Humans: Negative
Because humans have moved into much of the habitat of the bearded wood-partridges,
these birds often forage for food on agricultural land, and are therefore considered
crop pests in some places.
- Negative Impacts
- crop pest
Conservation Status
Due to habitat destruction (housing and agricultural development) and hunting, these birds are now considered locally extinct in some areas of Mexico and are listed as a species in high risk of extinction in the wild. Bearded wood-partridges are currently classified as "vulnerable" on the IUCN red list. They were first listed on the IUCN Red List of Threatened Species in 1988, and were reassessed by BirdLife International in 2005. It is estimated that there are fewer than 5,400 individuals in the world. Though recent studies suggest there are more individuals than estimated, populations continue to decline.
Few measures have been taken to help increase the bearded wood-partridge population,
but several conservation awareness programs targeted towards villages near partridge
habitat have been proposed. This species was successfully reintroduced to Xalapa in
2005. Ongoing research if focused on learning more about these birds so that they
can be better protected.
Additional Links
Contributors
Tanya Dewey (editor), Animal Diversity Web.
Madoka McAllister (author), Kalamazoo College, Ann Fraser (editor, instructor), Kalamazoo College.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- rainforest
-
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
- agricultural
-
living in landscapes dominated by human agriculture.
- riparian
-
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
- 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.
- young precocial
-
young are relatively well-developed when born
- 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.
- 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
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- choruses
-
to jointly display, usually with sounds, at the same time as two or more other individuals of the same or different species
- 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.
- soil aeration
-
digs and breaks up soil so air and water can get in
- food
-
A substance that provides both nutrients and energy to a living thing.
- threatened
-
The term is used in the 1994 IUCN Red List of Threatened Animals to refer collectively to species categorized as Endangered (E), Vulnerable (V), Rare (R), Indeterminate (I), or Insufficiently Known (K) and in the 1996 IUCN Red List of Threatened Animals to refer collectively to species categorized as Critically Endangered (CR), Endangered (EN), or Vulnerable (VU).
- omnivore
-
an animal that mainly eats all kinds of things, including plants and animals
- 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.
- 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.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Aguilar, S. 2006. "The Reintroduction of Bearded Wood-Partridge in Xalapa Has Been Successful" (On-line). Mexico eBird. Accessed October 14, 2006 at http://www.ebird.org/aVerAves/news/chivizcoyo_en_Macuiltepetl.html .
Butler, R. 2006. "Dendrortyx barbatus" (On-line). BETA: Biodiversity Education Through Action. Accessed October 14, 2006 at http://biodiversity.mongabay.com/animals/d/Dendrortyx_barbatus.html .
Edwards, E. 1972. A Field Guide to the Birds of Mexico . Sweet Briar: Ernest P. Edwards.
Edwards, E. 1998. A Field Guide to the Birds of Mexico and Adjacent Areas . Austin: University of Texas Press.
Eitniear, J., S. Aguilar-Rodriguez, J. Baccus, J. Carroll. 2001. Response Rates of Bearded Wood-Partridges to Playback of a Recorded Call. Vida Silvestre Neotropical , 10: 1-2. Accessed October 14, 2006 at http://www.icomvis.una.ac.cr/revista/pdf/Eitniear_2001.pdf .
Elphick, C., J. Dunning, Jr., D. Sibley. 2001. The Sibley Guide to Bird Life and Behavior . New York: Chanticleer Press, Inc..
Gale, T. 2005. "Bearded Wood-Partridge Information" (On-line). Grzimek's Animal Life Encyclopedia. Accessed October 14, 2006 at http://www.answers.com/topic/dendrortyx-barbatus .
Stiles, F., A. Skutch. 1989. A Guide to the Birds of Costa Rica . Ithaca, New York: Comstock Publishing Associates.
2006. "BirdLife Species Factsheet" (On-line). BirdLife International. Accessed October 14, 2006 at http://www.birdlife.org/datazone/search/species_search.html?action=SpcHTMDetails.asp&sid=312&m=0 .
2006. "Grey Partridge" (On-line). The Royal Society for the Protection of Birds. Accessed November 13, 2006 at http://www.rspb.org.uk/birds/guide/g/greypartridge/index.asp .
2006. "ITIS Standard Report Page: Dendrortyx barbatus" (On-line). ITIS Report. Accessed October 14, 2006 at http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=175920 .