Sunday, 24 March 2019

Striated Fieldwren

On the Bass Coast of Westernport Bay, I recently found a pair of Striated Fieldwrens (Calamanthus fuliginosus) by a tidal creek in Shrubby Glasswort (aka scrubby samphire - Tecticornia arbuscular), a dense shrub to about 2 metres in height.

Surrounding the Shrubby Glasswort was an open plain of a low growing (to about 300mm) glasswort species, also called samphire, which was subject to occasional tidal salt water inundation. Across the creek there was a dense White Mangrove forest. To complete this floristically simple habitat devoid of trees there was some Coast Saltbush (Atriplex cinerea) and some bare patches covered in a mat of bleached tide-washed seagrass.

The saltmarsh environment is ideal and typical habitat for this somewhat elusive Fieldwren. Also about twenty White-fronted Chats, another species that enjoys saltmarsh habitats, were foraging on the glasswort plain.

The male and female Striated Fieldwrens are similar however the male has a distinctive white supercilium (eyebrow) and chin (throat) whereas these parts are buffy yellow on the female.

Please click on photos to enlarge.

Note I have cropped the photos to a 3:5 ratio because I feel this reflects the flat very low relief habitat in which the Fieldwrens live.

At first the pair scurried about mouse-like on the ground between patches of glasswort.

This is the female – note the buffy eyebrow.
This is the male with tail typically cocked – both male and female hold their tails like this. Note the mat of bleached seagrass.

Even though this habitat is very simple, with possibly only three plant species present where the Fieldwrens live, there must be a rich enough supply of insects and seeds to sustain this sedentary species.

The male Striated Fieldwrens often move to the tops of low shrubs to view the surrounding area and will sing from these vantage points. The remaining photos are of the male perched on the tops of Shrubby Glasswort.

The tail is often wagged from side to side as seen in this photo.

Note the white tips on the tail feathers which are only visible from underneath.

I must confess to having a soft spot for Fieldwrens and Heathwrens – it is always a delight to find them and hear their beautiful songs which are quite loud for such small birds.