Frogmouths 2011

This post is going to roll around a tad, covering the activities of the Tawny Frogmouths that have bred on this property for the last 3 years.  They have adopted a number of additional roosts this year: some are becoming the most used, and some of the ones used frequently last year have declined in popularity quite markedly.  

To summarise a note I put in the June edition of Canberra Bird Notes, one of the new roosts I found by chance.   I was following a mixed feeding flock of 30 Yellow-rumped thornbills, Acanthiza chrysorrhoea 20 Buff-rumped Thornbills Acanthiza reguloides, a White-eared Honeyeater Lichenostomus leucotis , and a Grey Shrike-thrush  Colluracina harmonica when they mobbed a pair of roosting Tawny Frogmouths Podargus striodes perched in a Red Box Eucalyptus polyanthemos.  I also noted that HANZAB v4 includes 2 species of Treecreeper in the diet of Tawny Frogmouths but while a White-throated Treecreeper Corombates leucophaeus was in the same tree as the frogmouths it was not a participant in the mobbing.  Kaplan 2007 does not include any bird species in her list of frogmouth food items.

Another new roost - the most recent which I have found - is in a Yellow Box tree adjacent to our vegetable garden.  On the second occasion I found them here (note: this may not be the same as the second time they have used it) I only spotted them when looking from the vegie garden at some noisy thornbills and honeyeaters.  Spot the froggies in this!

Last year the male had started brooding on September 2nd.  Presumably that means the first egg was laid the previous night.  This year, by that date they hadn't started refurbishing the nest.  By 7 September I had just about decided they were not going to breed this year.  Then on that day I could only find the female which I took to mean that the male was busy brooding on a nest in a different site. 

As the birds had taken to roosting on the Western edge of their usual haunts I thought I would start looking for the new nest there.  It took very little time for me to find  the nest with the male in situ.

The similarities to the old nest site are that it is

1. in a fork on a horizontal branch; and 
2. about 5m above the ground

Otherwise:

1. the tree is a Stringybark (Eucalyptus macrorhyncha) rather than a Yellow Box (E. meliodora); and
2. the branch is about half the thickness of that used to support the previous nest.

This screenshot shows the relationship between the two nest sites.  The new one is (according to Google Earth) 63m from the old one, and pretty much due West from there. 

This year the most commonly used roost sites were to the West of the house while in the past they have been to the East.  Of course, being contrary, on the day after laying the female turned up in a roost site about 40m East of the old nest site!  She has spent most of her daytimes in sites close to the old site: here she is hiding in what I used to term "Nearest tree".

On consulting last year's records for duration of incubation, my guess is that the first egg should hatch on 5 October.

On 15 September a major ruckus by the Gang of 5 resident Australian Magpies announced the presence of a female Brown Goshawk in the vicinity.  At one point it seemed to pass through the canopy of the new nest tree before being escorted, noisily, from the premises.  While this was going on the male Frogmouth stretched itself out with head pointing upwards.  I suspect it was going to show the Goshawk just how wide a Frogmouth's beak can open!