Nest re-cycling

The male Tawny Frogmouth Podargus strigoides sits on the edge of the chough nest

Tawny frogmouths usually build their own nest, a simple platform of twigs and sprigs of greenery, although about one in forty nest records from my study of these birds in Canberra have been in old White-winged Chough Corcorax melanorhamphos nests. These are large, clay nests, which resemble bronze-age beakers set half-way along horizontal branches. In this case about fifteen metres up a Scribbly Gum tree. Frogmouth nests are often flimsy constructions, so perhaps they find these old firm structures as good bases for their nest. They add a few sprigs inside the cup, but don't fill it.

The female sits with the chicks - she has more red on her wings than the male

I have been monitoring the incubation, brooding and feeding rates of frogmouths over the years, studying differences in habitat and weather conditions. Some of this can be done by watching, but it is at times easier and less time-consuming to do this remotely with wildlife-monitoring cameras. So, with the help of Laura Rayner, who did the climbing to this nest, we set this one up, which was about fifteen metres up a gum tree. Once the camera was set and tested, we left the birds for the night and collected the camera the next night. I only approach these birds at night as I do not like to disturb them during the day when they can be vulnerable to predation. They behave so confidently at night, and these birds were feeding their chicks as we were setting up the camera a few metres away.

The chicks, at about two and a half weeks old, were beginning to fill the egg-cup nest

In this case, the adults fed the chicks seventy times overnight, so that was perhaps thirty-five feeds per chick, if they received equal shares. I don't know as I can't identify each chick in all the shots. About half the feeds were in the first two hours after dark, then the feeding rate decreased as the night progressed. And each adult only brooded the chicks for one period of about ten minutes, most of the time the chicks were alone in the nest.

Then as dawn approached the male came in to cover the chicks for the whole of the next day, for it is the male who guards the chicks all day, while the female roosts in a nearby tree. To watch some footage from the camera click here.

A chick peers over the lip of the clay nest

Tawny Frogmouths feeding two-week old chicks

The tawny Frogmouths which were featured in the previous film, now have three chicks over two weeks old. And they take a lot of feeding.

Here the female, the smaller and less boldly -marked bird, offers a small prey item to the chicks.

The oldest frogmouth chick is now eighteen days old, the other two one and two days less as they do not all hatch in one day. In the attached film, they can be seen to be very hungry at the beginning of the night when the female first brings in some food. They call very quietly in a hoarse whisper, and they compete for the food she brings by stretching up to her bill. In the early part of the night, when still lively, the chicks spend much of the time wriggling and shuffling, wing flapping and stretching. And during the first part of the night the adults were mostly away from the nest, although perhaps close by, but they never brooded the chicks during the main feeding period. 

All the food items were the same, unidentified, but long, thin and with tiny legs - centipedes?

The adult birds were totally silent all night. The background sounds are magpies and currawongs calling at dusk, then several species of frog calling during the night.

When the male first left the nest after his day-long stint, he brought in a sprig of vegetation to add to the nest, the chicks dismissed that as no use for food.

There were 129 food items brought in over the whole night, about 43 for each chick. Most were brought in during the first three hours at a rate of one every two minutes on average, but at times the birds brought in prey three times in a minute. Eventually, about one-o-clock, the chicks began to look sleepy and feebly lifted their heads for food. Then the female shuffled over and brooded them. From then on, the birds only brought six or seven items per hour, and they brooded the chicks for longer sessions as dawn approached. 

Click here to watch the film

(approx. 4 minutes and 10Mb)

The female settles to brood the chicks after a long three hours 

of almost continual supply of food to the chicks.

First Frogmouths have hatched

The female frogmouth comes in to the nest

The first tawny Frogmouths hatched over the 26-27th September, taking less than forty hours from the first fidgeting of the incubating adult to seeing the two chicks in the nest. All this was recorded using a remote camera, set to record on registering movement in the field of view. There is very little sound on the recording as all took place in silence: the birds did not call to one another, the chicks did not even cheep when begging for food, and the birds' flight is almost silent. This is all in defense against predators hearing them, especially powerful owls, even though there are none near the nest?. They are considerable predators in parts of the Tawny Frogmouth's range.

To see more, click on the link to a YouTube video below, it is 3m 20sec long and 7Mb.

Tawny Frogmouths feeding newly-hatched chicks

The video opens with the male sitting on the nest, as he had done for the whole previous day. The female then comes to relieve him of his duties, but brings no food for the chicks as she would not have known there were chicks in the nest - they had hatched since her last vigil on the previous night. 

The male is recognizable as the larger bird, with a broad, well striped head, bold necklace markings and stronger markings on his wing and tail feathers. She is smaller and has less markings.

He then comes in with the first food for the newly-hatched chicks. The prey they both bring in is small, linear, legless and wingless - earthworms? The chicks were fed thirteen times during the night, seven by the male and six by the female, each taking it thier turn.

The male delicately feeds the chicks with their first meal

The camera used was a Bushnell Trophycam HD, with black flash.