Eumomota superciliosa

Geographic Range

Turquoise-browed motmots ( Eumomota superciliosa ) are commonly distributed throughout Central America from southern Mexico in the north, to northwest Costa Rica in the south. Along the Caribbean they are most prevalent in the Yucatan Peninsula and the mountain-rimmed valleys of northwest Guatemala and Honduras. Near the Pacific they frequent the Gulf of Nicoya in Costa Rica.

• Biogeographic Regions
• neotropical neotropical
  • native native

Habitat

Turquoise-browed motmots occupy the open semi-arid lowland regions of forest, scrub forest and grazing pasture land of their range. In the arid semi-desert section of the Motagua Valley in Guatemala they are exceedingly abundant, being one of the most numerous species of bird in the region. Turquoise-browed motmots are also present in the tropical regions, but less plentifully, where they inhabit the secondary-growth and less dense forests along with cleared areas. They are not common in the dense rainforest. Depending on their locality, they prefer to nest in the walls of terraces, crevices and caverns of porous rock, and along the sandy banks near rivers, where they dig long burrows. Their burrows range from 100 to 160 cm in length, but the longest was found to be 244 cm long.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• forest forest
• scrub forest scrub forest

Physical Description

Turquoise-browed motmots are monomorphic birds that have an average mass of 66.5 g, and are approximately 34 cm long. Males are slightly larger than females. They consist of mixture of green and red earth tones with turquoise accents. Starting with its distinctive broad turquoise band above each eye, they have a back bill and extending from its base a black line that surrounds the eye and progresses to the ear. Underneath this black band from the bill to the eye is a very thin strip of turquoise. Behind the eye lays a triangular patch of chestnut. On the throat is a short black bib, fringed with turquoise. The body is a blend of olive-green, with chestnut on the back and belly. Their wings are comprised of olive-green coverts, turquoise remiges, and a black band along the tips. They have a wingspan of 122 mm. The two central tail feathers makeup much of the motmots overall length. The shape of the two central feathers is unique in that the middle portion of barbs is missing, leaving a small disc-shape at the end. The feathers initially grow intact, but the middle barbs are weakly attached to the shaft. These barbs easily fall off during regular preening or daily activity. Both male and female motmots feature these distinctive tail feathers, however males' tails are longer. Turquoise-browed motmots are identified from other species of motmot in the area by the longer length of vaneless shaft on their tail. The young take around twenty-five days to reach coloration like the adults.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• male larger

Reproduction

Although turquoise-browed motmots are monomorphic, males' tail length aids in sexual selection. Males with longer tails have greater pairing and reproductive success. Adults show fidelity to one another during the breeding season and may pair off exclusively for a few years at a time, in which they will nest in the same area and possibly the same burrow.

• Mating System
• monogamous monogamous

Turquoise-browed motmots' mating season begins in March. By late March, burrows are being made and eggs may be laid from April to May. Mating pairs will dig their burrows close together except when space is ample, then they prefer to be further apart from others.

Both the male and female take part in excavating their burrow. Depending on the site, they commence digging in the exposed edge horizontally, and with their feet they excavate their burrow. The entrance has been recorded to be 9 cm in width by 7.5 to 10 cm in height, and over the course of several days the burrow can grow to become 100 to 160 cm in length and will be slightly curved to one side. On the inside end the burrow widens into a chamber. The longest a burrow has been recorded at is 244 cm. The incubation period is around 17 days.

They make a bed beneath the eggs by regurgitating the indigestible fragments of their past meals on to the floor of their burrows. Turquoise-browed motmots can raise two broods in a single season, usually with 3 to 4 eggs in each and rarely 5. Their eggs are white and range from 7.5 to 8.5 g.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Both male and female turquoise-browed motmots build the nest. The adults share in incubating and care taking of the eggs and young. To switch incubators, one individual calls out in a low voice while perched upon the burrows entrance, signaling to their mate that they will take over. The incubation period is around three weeks. From the first shell pip, it can take 1 to 3 days for the motmots to break through their shells. Upon hatching, birds are blind with pink skin and featherless. The nestlings remain in the burrow until they learn how to fly decently, which is takes from 25 days to 1 month. When they sense a disturbance by their burrow the adults approach with caution, never going directly in. They will first scan the area from a perch, then after ensuring it is safe they will return.

• Parental Investment
• altricial altricial
• male parental care male parental care
• female parental care female parental care
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female

Lifespan/Longevity

Currently no information is known regarding the lifespans of turquoise-browed motmots.

Behavior

Turquoise-browed motmots are social birds that exhibit colonial nesting. They are active during the day, and are non-migratory. Turquoise-browed motmots spend much of their time perched motionlessly and silently among tree branches. This time in the trees is spent surveying the area for food. Occasionally their head turns from one side to another at intervals and their tail swings slowly back and forth. They usually fly brief distances but in a rapid or wavy motion. Mated adults will perch along side of one another.

In the presence of predators both the male and female will move their tail side-to-side several times in a row, then will pause momentarily and begin again. They will do so the entire length of time the predator is present. The tail commonly rises above the head before each “wag” and in the upward and downward motion the tail makes a letter “Z” pattern. A clucking sound is often made in predator-induced wag-displays. There is evidence to support these displays serve to intimidate and deter predators.

• Key Behaviors
• arboreal arboreal
• flies
• diurnal diurnal
• motile motile
• sedentary sedentary
• social social

Home Range

Territory size for turquoise-browed motmots is currently unknown.

Communication and Perception

Turquoise-browed motmots are generally quiet, with exception to the mating season. During this time, using a loud, deep, and gruff voice the adults regularly give a drawn-out cawaalk , or a cawak cawak , in succession. In dismay they may give off low throaty sounds. The adults have also been heard giving off a wha wha sound, while the other adult feeds the young. Nestlings make a weak, hoarse peeping sound in response to their parents and when disturbed. As they grow older it turns into a more throaty noise that mimics that of their parents.

The nestlings will make a cheep sound when begging for food, which will last until they are 12 to 15 days old. Another begging call is snore , this replaces the cheep , it is also used during aggressive interactions with nest mates and they use it until after they are fledged. Once the birds are at least 22 days old they began to call K’wa-rr , which is louder than the other calls and not used while begging. This is thought to be an immature version of the fledgling call k’wahoo .

There have been 5 distinct post-fledgling vocalizations recorded. Chirr is a contact note, and may serve as a locator to the parents. A loud K’wahoo is given by chicks 30 to 45 days old when hungry. It could also function as a location call to parents. Kawukawuk is a loud call given commonly in the early morning and late evening, and intermittently throughout the day, that occurred at 40 days old. Once started, the other birds would join in calling it, indicating that it may be an alarm signal. Honk is a common mild alarm note indicating when there is a disturbance near the nest. It begins at around 38 days and continues into adulthood. Wuk , tok , and tok-ta-wuk were given as a strong alarm.

During aggressive interactions it is common for turquoise-browed motmots to flatten down their crown feathers and spread and display their turquoise brow feathers, in extreme circumstances the brow feathers may reach across the top of their head. Turquoise-browed motmots also utilize a tail-wagging maneuver in the presence of predators that likely aims to intimidate and scare away the intruder.

Visual communication is likely an important aspect of sexual selection for turquoise-browed motmots. It is hypothesized that tail feather length in males corresponds to fitness and influences mate selection by females.

Like all birds, turquoise-browed motmots perceive their environment through visual, auditory, tactile and chemical stimuli.

• Communication Channels
• visual visual
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Turquoise-browed motmots have a broad diet, consuming an assortment of insects including caterpillars, butterflies, and beetles along with worms, spiders, and lizards. Their curved bill, along with their keen sense of sight allows them to plunge down and snatch their prey abruptly, either from the vegetation or out of mid air. Along the outer third of their beak both mandibles are equipped with finely serrated edges, giving them a better grip on their prey. They stay perched motionlessly on tree branches until they see a prey item, then they strike. Without landing, they swiftly catch their prey then take it directly back to their original perching site or burrow, where it is knocked senseless before it is consumed. When feeding their young lizards, the adults will often peck off the head in order for the soft innards to be pushed through the neck.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• reptiles
• insects
• terrestrial worms

• Plant Foods
• seeds, grains, and nuts
• fruit

Predation

Feral cats and dogs, white-nose coati (Nasua narica), gray foxes ( Urocyon cinereoargenteu ), coatimundis ( Nasua narica ), snakes, and birds of prey are predators of turquoise-browed motmots.

Ecosystem Roles

Turquoise-browed motmots are secondary and tertiary consumers, omnivorous and fairly common, therefore they may help control insect species. They aid in seed dispersion of the rose woodson ( Stemmadenia donnell-smithii ), holywood ( Guaiacum sanctum ), and other fruit bearing trees in their diet. They provide sustenance to the white-nose coati ( Nasua narica ), gray foxes ( Urocyon cinereoargenteus ), and a variety of birds of prey. After the motmots are through using their burrows, rough-winged swallows ( Stelgidopteryx serripennis ) may build their nests in them.

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

The unique tail feathers and coloration of this species have intrigued many, and are sought out by birders, naturalists, photographers, cinematographers, and other visitors, providing eco-tourism revenue. Turquoise-browed motmots are the national bird of El Salvador and Nicaragua.

• Positive Impacts
• ecotourism ecotourism

Economic Importance for Humans: Negative

Turquoise-browed motmots have no known negative effects on humans.

Conservation Status

According to the IUCN turquoise-browed motmots are of least concern due to their extensive geographic range and stable population size. They are fairly common and not considered threatened.

Additional Links

Encyclopedia of Life

Contributors

Constance Johnson (author), Northern Michigan University, Alec Lindsay (editor), Northern Michigan University, Rachelle Sterling (editor), Special Projects.

References

Eckelberry, D. 1959. The Turquoise-Browed Motmot. The Condor , Vol. 61, No. 1: 3.

IUCN, 2010. "Birdlife International" (On-line). IUCN Red List of Threatened Species. Accessed March 30, 2010 at http://www.iucnredlist.org/apps/redlist/details/142102/0 .

Martin, R., M. Martin. 1980. Observations on the Breeding of Turquoise-Browed Motmots in Yucatan. The Condor , Vol. 82, No. 1: 109.

Martin, R., P. Scott, M. Martin. 1989. Mate Fidelity and Breeding-Site Specificity of the Turquoise-Browed Motmot. The Condor , Vol. 91. No. 1: 217-219.

Murphy, T. 2008. Lack of Assortative Mating For Tail, Body Size, or Condition in the Elaborate Monomorphic Turquoise-Browed Motmot (Eumomta superciliosa). The Auk , Vol. 125, No 1.: 11-19.

Murphy, T. 2007. Lack of Melanized keratin and barbs that fall off: How the Racketed Tail of the Turquoise-Browed Motmot Eumomota supercilliosa is formed. Avian Biology , Vol. 38: 139-143.

Murphy, T. 2006. Predator-Elicited Visual Signal: Why the Turquoise-Browed Motmot Wag-Displays its Racketed Tail. Behavioral Ecology , Vol. 17, No. 4: 547-553.

Remsen, J., M. Hyde, A. Chapman. 1993. The Diets of Neotropical Trogons, Motmots, Barbets and Toucans. The Condor , Vol. 95, No. 1: 178-192.

Scott, P., R. Martin. 1986. Clutch Size and Fledging Success in the Turquoise-Browed Motmot. The Auk , Vol. 103, No. 1: 8-13.

Skutch, A. 1947. Life History of the Turquoise-Browed Motmot. The Auk , Vol. 64, No. 2: 201-217.

Smith, S. 1976. Predatory Behaviour of Young Turquoise-Browed Motmots, Eumomota superciliosa. Behaviour , Vol. 56, No. 3-4: 309-320.