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Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Caprimulgiformes — nightjars, poor-wills, and allies
Family: Podargidae — frogmouths
Genus: Podargus (Vieillot, 1818) — frogmouths
Species: Podargus strigoides (Latham, 1801) — Tawny Frogmouth
Subspecies: Podargus strigoides strigoides (Latham, 1801) — eastern Australia and Tasmania
Subspecies: Podargus strigoides brachypterus (Gould, 1841) — western and central Australia
Subspecies: Podargus strigoides phalaenoides (Gould, 1840) — northern Australia
Sources: Gill and Donsker (2019); ITIS (2019)
Synonyms
Podargus plumiferus (Gould 1840)
Caprimulgus strigoides (ITIS 2019)
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Body Weight
P. s. phalaenoides: 205-364 g (7.23-12.8 oz) (Holyoak 2019)
P. s. strigoides: 180-680 g (6.3-24 oz) (Holyoak 2019)
Note: At the species level, Kaplan (2018) reports a typical minimum weight of 300 to 350 g (10-12.3 oz; sexes combined) and a maximum weight of 750 g (26 oz) in a male. Geographical variation, sexual dimorphism, and seasonal weight loss/gain contribute to reported weight differences.
Body Length
34-53 cm (13-21 in) (Holyoak 2019)
P. s. phalaenoides and P. s. brachypterus smaller than P. s. strigoides (Holyoak 2019).
Tail Length
About 20 cm (8 in) (Kaplan 2018)
General Appearance
Medium-sized owl-like bird. Head large (Marchant and Higgins 1999). Wing tips rounded. Tail short (Holyoak 2019). Eyes large and oriented forward. Beak large; particularly wide in males. Pronounced feathers above beak (Kaplan 2018).
Coloration
Camouflage with tree limbs and trunk (Körtner and Geiser 1999a). Feather patterns vary by location, sex, and individual traits; may change with latitude (Holyoak 2019).
Adult: Upperparts typically grayish with wide streaks and fine barring. Underparts pale grayish with fine to wide streaks, reddish-brown hues, and variable white barring. Female often darker than male and more reddish (Holyoak 2019). Legs and feet gray. Inside of beak yellow to bright green (Marchant and Higgins 1999; Kaplan 2018).
Juvenile: Similar to adult. Less contrast in streaking (Holyoak 2019).
Nestling: Down transitions from white to gray with white flecking and barring, and a paler underside (Kaplan 2018; Holyoak 2019).
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Range
Australia, including Tasmania (Birdlife International 2016)
Habitat
Eucalyptus forest, woodlands, mallee and acacia shrublands. Trees/shrubs along rivers, coasts, roadways, parks, farmlands, large gardens, and urban parks. Need trees or shrubs for roosting and nesting. Use high perches while hunting (Marchant and Higgins 1999; Weaving et al. 2016; Holyoak 2019).
IUCN Status
Least Concern (2016 assessment) (Birdlife International 2016)
CITES Appendix
Not listed (UNEP 2019)
Other Designations
Protected as a native species of Australia under the Environment Protection and Biodiversity Conservation Act of 1999 (Department of the Environment 2019).
Populations in the Wild
No global population estimates. Considered common (del Hoyo et al. [1999] as cited by BirdLife International [2016]; Holyoak 2019). Population declines in local areas but not distribution-wide (Birdlife International 2016; Holyoak 2019).
Threats to Survival
Deforestation, where no trees remain. Loss of habitat, including loss of insect food.
Indirectly poisoned (especially near urban areas) by pesticides used to manage cockroach, snail, and rodent populations (Kaplan 2018).
Hit by motor vehicles while flying toward ground after prey (Rose and Eldridge 1997; Kaplan 2018).
Predators include feral cats and non-native fox (Kaplan 2018).
Also reported: loss of nests, shooting, collisions with wire fences (Marchant and Higgins 1999; Kaplan 2018; Holyoak 2019).
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Activity Cycle
Short alternating periods (about 2 hours) of sleep and wakefulness. Often labeled “nocturnal” because more active at night; more research needed (Kaplan 2018). Daytime roosting behavior includes sitting in a relaxed or camouflaged posture (if disturbed), presumably to avoid detection by daytime avian predators. Also preen, sleep, and care for young during the day (Marchant and Higgins 1999; Kaplan 2018). Commonly feed at twilight and at night (Kaplan 2018). During cold weather, use torpor (reduction of body temperature and metabolism) for short periods to conserve energy (Körtner et al. 2000; Körtner et al. 2001; Kaplan 2018).
Movements
Pair or family group holds a small territory year-round. Territory defended by adult male (Kaplan 2018; Holyoak 2019). Young disperse in summer of first year (Kaplan 2018).
Social Behavior
Strong bond between mates; roost near each other. Other interactions between potential mates, and between parents and their young (Kaplan 2018).
Agonistic Behavior and Defense
Camouflage themselves by stretching head and body into straight line, tightening feathers against body, closing eyes, and freezing in place; resemble a tree branch. When detected, raise head feathers and open beak to deter other birds from approaching; streaks on feathers may present a “spiky” appearance, when raised. If cornered, raise body feathers to appear larger, duck head, stare, snap bill, and growl. Sometimes extend wings. Open colored mouth wide as threat display (Marchant and Higgins 1999; Kaplan 2018). Spray strong-smelling feces, possibly to deter or confuse reptilian predators (Kaplan 2018).
Communication
Call frequently (oom-oom-oom), especially during breeding season when males and females perform duets. Vocalizations soft and low pitched (Kaplan 2018; Holyoak 2019). Threat calls include grunts (Marchant and Higgins 1999). Distress and warning calls loud and high pitched (Kaplan 2018). Young make croak-like calls when begging for food (Marchant and Higgins 1999).
Visual displays include raising feathers (on back, around face) and dilating pupils (Kaplan 2018).
Diet
Commonly large insects (cockroaches, beetles, moths), scorpions, spiders, centipedes, frogs. Feed on both terrestrial and flying insects (Rose and Eldridge 1997; Kaplan 2018; Holyoak 2019).
Occasionally earthworms, snails, slugs, crustaceans, millipedes, lizards, small birds, small mammals (Rose and Eldridge 1997; Holyoak 2019).
Feeding
“Sit and wait” predator but versatile hunters—catch insects mid-air, glean prey from branches, and forage on the ground. Take large prey to tree perch for consumption. Beak efficient at crushing and pulping prey. Use only beak, not feet, for manipulating prey (Marchant and Higgins 1999; Kaplan 2018).
Predators
Adults: feral cats, foxes, dogs, pythons (Kaplan 2018)
Eggs and nestlings: many birds (e.g., ravens, currawongs, owls, goshawks), rodents (particularly bush rats), tree-climbing snakes (particularly pythons), lace monitor lizards (Kaplan 2018)
Locomotion
Mostly sit and fly. On the ground, walk only a few steps before flying to another habitat patch. Snatch flying insects mid-air (Kaplan 2018).
Relationship with Humans
Often nest in backyards. Helpful to humans in reducing “pest” populations (feed on cockroaches, scorpions, centipedes, snails, small rodents, etc.). Nestlings hand-raised by wildlife rehabilitators, if orphaned after falling from nest. Common in zoos (Kaplan 2018; ZIMS 2019).
Also see Threats to Survival.
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Breeding and Parental Care
Breeding season August to January, with peak laying from September to October. Solitary pair defends breeding territory; thought to form strong lifelong pair bond. Behaviors that reinforce pair bond: grooming (mainly by the male), mouth gaping, leaning against each other, and roosting near each other (especially during breeding). Courtship behaviors not well known. Nest comprised of loose sticks and twigs, with a shallow depression lined with leaves, grass, or other soft materials. Often placed at the fork of a tree, about 3 to 10 m (10 to 33 ft) above the ground. Built by male and female. Nest position often precarious; egg and young sometimes fall from nest. Daytime incubation by male; nighttime thought to be by female. After eggs hatch, parents take turns brooding and feeding young. Low nestling survivorship (Marchant and Higgins 1999; Kaplan 2018; Holyoak 2019).
Sexual Maturity
Less than 12 months of age (Kaplan 2018)
Incubation Period
28 to 32 days (Körtner and Geiser 1999b; Holyoak 2019)
Clutch Size
Typically 1 to 3 eggs (2 most common) (Körtner and Geiser 1999b; Rae 2017; Kaplan 2018; Holyoak 2019)
Interbirth Interval
One clutch per year. Rarely, replacement clutch laid, if first is lost (Marchant and Higgins 1999; Holyoak 2019). Double brooding usually unsuccessful, based on limited observations (e.g., Weaving et al. 2016).
Weight at Hatching
Approximately 17 to 19 g (0.60 oz) (Körtner and Geiser 1999b; Kaplan 2018)
Video: Tawny Frogmouth chick’s first month at St. Louis Zoo
Fledging
Young leave nest at 27 to 32 days. Because young hatch and develop asynchronously, younger, less well-developed nestlings often fall to ground and eaten by predators. Surviving fledglings fed by parents for an additional 2 to 6 weeks. May remain with parents for several more months (Körtner and Geiser 1999b; Marchant and Higgins 1999; Kaplan 2018; Holyoak 2019).
Typical Life Expectancy
Wild populations: not well known (Kaplan 2018)
Managed care: median life expectancy of about 21 years for males and 15 years for females (AZA 2023).
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(Kaplan 2018)
- Cope with temperature extremes very well
- Feathers are waterproof—can be rained on and remain dry
- Able to open beak very wide
- Lower bill lightweight: skin supported by a bony frame (like a pelican’s)
- Beat large or tough prey against perch before swallowing
- During hatching, egg shell splits lengthwise (unusual among birds)
- Can keep one eye at least partially open while asleep to respond to potential predators
- Can move eyes apart and closer together as well as in opposite directions
- An iconic bird in Australia
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