Regent Bowerbird Sericulus chrysocephalus Scientific name definitions

24·5 cm; male 76–110 g, female 91–138 g. Male has forehead, crown, nape and upper mantle brilliant deep yellow, often washed darker flame-scarlet on fore­crown; forehead and crown feathers short, dense, plush-like; remaining upperparts and entire underside jet-black, including narrow arching line over eye; two outermost primaries and all upperwing-coverts matt black, remainder of primaries largely golden-yellow with broad to narrow black tips and leading edges, secondaries (lacking black leading edges) with black tipping becoming smaller towards innermost feathers, latter and most tertials entirely yellow; rectrices black, some individuals with fine central yellow terminal tips, others with yellow on outer edges of inner webs of some rectrices; iris bright yellow; bill orange-yellow ; legs blackish-brown. Female is on average larger than male in weight and body, but not in bill length; plumage differs radically, variable dull dirty off-white to drab grey on head, which finely streaked, mottled and smudged and with contrasting dull sooty-black crown patch, upperparts variably olive-brown, mantle spotted off-white, dirty off-white to creamish below, broad central line of dull sooty-black feathers down throat, underparts broadly barred blackish-brown; old females may have darker forehead, and may show some plumage characters of adult male; iris dark brown, bill blackish. Newly fledged juvenile has well-developed wing feathers and down persisting on crown, nape and mantle, this then replaced by soft and loosely textured plumage resembling immature of both sexes, one-month-old juvenile has striking crown and nape pattern, dark brown iris, blackish bill, light grey legs; immature male like female, acquires adult plumage, iris and bill coloration gradually (mostly during fourth and fifth years); subadult male (by sixth year) variable, like immature male with few feathers of adult plumage intruding to like adult male with few feathers of immature plumage remaining, and with almost completely yellow eye and orange bill, full adult plumage gained in seventh year; female in first post-juvenile plumage more densely/heavily scalloped and barred ventrally than adult, black crown bordered around nape with narrow line of dark grey, retains typical brown plumage and dark bare parts and iris to third year, but by end of fourth year iris may be yellow with brown mottling.

• Regent x Satin Bowerbird (hybrid) Sericulus chrysocephalus x Ptilonorhynchus violaceus

Coastal zone of CE Australia from E Queensland (Connors and Clarke Ranges, on Eungella Plateau) S, with distributional gap about Fitzroy R Valley inland of Rockhampton, to E New South Wales (to area immediately N of Sydney).

Subtropical rainforest, associated sclerophyll woodland, and more open habitats, including cultivated country and urban gardens; sea-level to 900 m, altitudinal limits varying across range. Traditional bower sites dispersed through appropriate ridgetop habitat; tend to be within rainforest on flat or less sloping ground, with immediate liana-thicket cover providing concealment and protection.

Resident. Localized movement to lower altitudes may occur during winter months; individuals in female-like plumage said to make such movements 3–4 weeks earlier than adult males. Of 22 marked individuals recaptured, longest distance travelled was 4 km.

Mostly fruits , also flowers (buds, petals, nectar), seeds , leaves, and arthropods (mostly insects); most leaf-eating during Jul–Oct non-breeding season. Nestling diet fruits and insects; insects include cicadas (Cicadidae), caterpillars, katydids (Tettigoniidae) and beetles (Coleoptera), cicadas representing significant dietary component. Forages mostly in upper levels of trees. Catches arthropods primarily by gleaning and hawking. Often forages alongside other bowerbirds and other fruit-eating bird species, actively displaces other species from fruiting trees; females dominate males at feeding trees; sometimes forms mixed-species foraging flocks with Ptilonorhynchus violaceus and Pied Currawongs (Strepera graculina).

Away from bowers the least vocal member of family; in courtship gives typical harsh grating notes and continuous subsong of avian mimicry.

Season Sept–Feb, peak in egg-laying Nov–Dec, fledging late Feb to early Mar, nesting cycle c. 3–4 months; display season Sept–Jan on Sarabah Range, earlier at some other localities. Polygynous, promiscuous male building and decorating small avenue bower; female builds and attends nest alone. Non-territorial, except for defence of bower site by male, which may attend same site for at least three seasons; for 24 traditional bower sites in Sarabah Range (Queensland), mean nearest-neighbour distance 195 m. Bower a sparse, frail avenue of sticks (sticks touching each other often become fused by whitish fungus), mean dimensions of 33 bowers (Sarabah Range) 23 cm long and 20 cm wide externally, avenue 8 cm wide and 18 cm high, average deviation of 44 avenues from N-S compass orientation 38°; male spends only c. 3% of daylight time at bower site; bower decorations (up to c. 30) include green leaves, pale flowers and petals, seeds, fruits, snail shells, cicada nymph ectoskeletons, and human-made blue items; "painting" of bower and theft of decorations occur; bower structure often short-lived (ten days or less), as regularly destroyed by rival males, or by owner when a rival known to have found it, new bower takes c. 3–4 hours to build (beneath different thicket within same site). Male attracts females in upper forest canopy by means of his bright plumage (rather than, as with other bowerbirds, vocalizations), then leads females to bower site; male courtship consists of three display elements, Initial Bower Display at avenue entrance to bower, Peripheral Bower Display around bower, and Central Bower Display within bower avenue; display postures include wing-flicking, gaping, Nape-presentation postures, and male also charges at female and makes brief vertical "flights", all presenting/enhancing plumage coloration. Nest a frail shallow saucer of loosely placed sticks, egg-cup lining of finer twigs and occasionally a few leaves, cryptically sited 2–31 m above ground in dense foliage of clump of vines, mistletoes (Loranthaceae) or other plant; mean distance of four active nests from nearest active bower was 266 m (closest 20 m). Clutch 1–3 eggs, mostly 2, in captivity laid on alternate days; in captivity, replacement clutch laid in new nest after failure; incubation c. 17–21 days, nestling period 17 days. Overall success of seven nests in Sarabah Range 43 %. Female may first breed in third year, more often in fourth year. Maximum recorded longevity of male at least 23 years.

Not globally threatened. Restricted range species: present in Eastern Australia EBA. Locally common or moderately common in larger forest "islands"; uncommon in small remnants. Numbers have diminished in several areas as a result of habitat loss and degradation. Once common about Sydney, but S limit of range now Gosford/Hawksbury R area of New South Wales. Break in distribution in N of range from near Casino to Woolgoolga, with small isolated populations at Iluka and Washpool; absent from Guy Fawkes R valley, where former presence may have linked populations; absence from Comboyne Plateau and Hunter Valley (New South Wales) probably result from clearing of rainforest. Adult males were once hunted for mounting as household novelties, and common in cabinets of mixed birds. Most populations appear fairly stable today.