Tawny Frogmouth

## Description

The tawny frogmouth (Podargus strigoides ) is a species of frogmouth native to the Australian mainland and Tasmania and found throughout. It is a big-headed, stocky bird, often mistaken for an owl, due to its nocturnal habits and similar colouring, and sometimes, at least archaically, referred to as mopoke or mopawk, a name also used for the Australian boobook, the call of which is often confused with that of the tawny frogmouth.

## Appearance

Tawny frogmouths are large, big-headed birds native to Australia that are often mistaken for an owl due to their nocturnal habits and similar coloring. They are sometimes incorrectly referred to as "mopoke", a common name for the Australian boobook, whose call is often confused with Tawny frogmouths'. These are stocky and compact birds with rounded wings and short legs. They have wide, heavy, olive-grey to blackish bills that are hooked at the tip and topped with distinctive tufts of bristles. Their eyes are large and yellow in color. Tawny frogmouths have three distinct color morphs, grey being the most common in both sexes. Males of this morph have silver-grey upperparts with black streaks and slightly paler underparts with white barring and brown to rufous mottling. Females of this morph are often darker with more rufous mottling. Females of the populations in Eastern and South-Eastern Australia have a chestnut morph and females from Northern Australia have a rufous morph.

## Distribution

Tawny frogmouths are found throughout most of the Australian mainland except in far western Queensland, the central Northern Territory, and most of the Nullabor Plain. In Tasmania, they are common throughout the northern and eastern parts of the state. These birds can be found in almost any habitat type, including forests and woodlands, scrub and heathland vegetation, and savannahs. However, they are rarely seen in heavy rainforests and treeless deserts. They are common in areas populated with many river gums and casuarinas and can be found along river courses if these areas are timbered. Tawny frogmouths are also common in suburbs, having adapted to human presence and may nest in parks and gardens with trees.

## Behavior

Tawny frogmouths live in pairs. During the day, they generally perch in the tree and do not actively look for food, though they may sit with their mouths open, snapping them shut when an insect enters. As dusk approaches, they begin actively searching for food. Tawny frogmouths feed mainly by pouncing from a tree or other elevated perch to take large insects or small vertebrates from the ground using their beaks with great precision. Some smaller prey, such as moths, can be caught in flight. Foraging flights consist of short, snatching flights to foliage, branches, or into the air. Due to a cryptic plumage Tawny frogmouths can be well camouflaged as part of the tree when they perch low on tree branches during the day. Their plumage allows them to freeze into the form of a broken tree branch and become practically invisible in broad daylight. Often, a pair sits together and points their heads upwards, only breaking cover if approached closely to take flight or warn off predators. When threatened, adults make an alarm call that signals to chicks to remain silent and immobile, ensuring that the natural camouflage provided by the plumage is not broken. Tawny frogmouths have a wide range of vocalizations; they generally use low-frequency sounds to communicate, though some of their warning screams can be heard for miles. Nestlings make a number of unique calls expressing distress, hunger, and fear. When disturbed during rest, frogmouths can emit a soft warning buzz that sounds similar to a bee, and when threatened, they can make a loud hissing noise and produce clacking sounds with their beaks. At night, these birds emit a deep and continuous "oom-oom-oom" grunting and a soft, breathy "whoo-whoo-whoo" call.

## Diet

Tawny frogmouths are carnivores and feed mainly on large nocturnal insects, such as moths, as well as spiders, worms, slugs, and snails but also a variety of bugs, beetles, wasps, ants, centipedes, millipedes, and scorpions. They also consume large numbers of invertebrates, small mammals, reptiles, frogs, and birds.

## Reproduction

Tawny frogmouths are monogamous and mate for life. During the breeding season, pairs roost closely together on the same branch, often with their bodies touching. The male carries out grooming by gently stroking through the plumage of the female with his beak in sessions that can last for 10 minutes or more. The breeding season lasts from August to December, but populations in arid areas may breed in response to heavy rains. Males and females both share in the building of nests by collecting twigs and mouthfuls of leaves and dropping them into position. Nests are usually placed on horizontal, forked tree branches and can reach up to 30 cm in diameter. Loose sticks are piled together, and leaf litter and grass stems are placed to soften the center. The nests are very fragile and can disintegrate easily. The female lays a clutch of one to three eggs which are incubated within 28-32 days. Both parents share incubation of the eggs during the night, whilst during the day, males incubate the eggs. Once hatched, both parents feed and tend the altricial (helpless) chicks. The young fledge 25-35 days after hatching and become independent.

## Population

### Population threats

Tawny frogmouths face a number of threats from human activities and pets. They are often killed or injured on rural roads during feeding, as they fly in front of cars when chasing insects illuminated in the beam of the headlights. Large-scale land clearing of eucalypt trees and intense bushfires are serious threats to their populations, as they tend not to move to other areas if their homes are destroyed. House cats are the most significant introduced predator of the Tawny frogmouth, but dogs and foxes are known to also occasionally kill the birds. When Tawny frogmouths pounce to catch prey on the ground, they are slow to return to flight and vulnerable to attack from these predators. As these birds have adapted to live in close proximity to human populations, they are at high risk of exposure to pesticides. Continued widespread use of insecticides and rodent poisons are hazardous as they remain in the system of the target animal and can be fatal to a Tawny frogmouth that eats them.

### Population number

The IUCN Red List and other sources don’t provide the number of the Tawny frogmouth total population size. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.

### Ecological niche

Tawny frogmouths are considered to be among Australia's most effective pest-control birds, as their diet consists largely of species regarded as vermin or pests in houses, farms, and gardens.

## Fun Facts for Kids

The Tawny frogmouth was first described in 1801 by English naturalist John Latham. Its scientific name 'strigoides' comes from the Latin 'strix' meaning "owl" and 'oides' meaning "form".

Although related to owls, the closest relatives of Tawny frogmouths are the oilbirds, potoos, owlet-nightjars, and true nightjars.

In 2019, Australian readers of The Guardian online voted the Tawny frogmouth as the second most popular bird in the Australian Bird of the Year poll.

Before and during the breeding season, male and female Tawny frogmouths perform duets consisting of call sequences that either alternate between partners or are performed simultaneously. They also make distinctive drumming noises during the breeding season.

The wide distribution range of the Tawny frogmouth includes areas of the Australian continent where winter nights are cold and warm summers can have extremes above 40°C. The high temperatures in summer and low temperatures in winter provide a thermoregulatory challenge for Tawny frogmouths that roost all day out in the open. During summer, they tend to choose positions on branches that do not have all-day exposure to sunlight. Faced with further heat stress, Tawny frogmouths engorge the blood vessels in the mouth and produce mucus that helps to cool air as it is inhaled, and hence cool the body.

During winter, Tawny frogmouths choose branches that are more exposed to sunlight to increase body heat. Pairs often roost and huddle to share body warmth. During daylight, Tawny frogmouths sometimes perch on the ground to sunbathe, remaining motionless up to 5 minutes. During this time, the birds open their beaks wide, close their eyes, and move their heads to the side to allow sunrays to penetrate beneath the thick layer of feathers.

In order to survive during winter, when the food supply shrinks drastically Tawny frogmouths spend much of their days and nights in torpor. Torpor is different from hibernation; it only lasts for relatively short periods of time, usually a few hours.