Secretarybird Infographic 4 Displays
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SECRETARYBIRD BEHAVIOURDISPLAY TERRITORIAL DISPLAYS Secretarybirds will defend their nest and undertake territorial displays. SOARING PENDULUM FLIGHT Flying in thermals Performing undulating high above the nest. manoeuvers in the air close to the nest. OPEN-WING DISPLAY Secretarybirds will pursue any intruder with an open-wing display along the ground with wings held above its back. If the intruder is overtaken, the bird will jump above it, striking downward with its feet. After the intruder withdraws, the pair will walk around each other with crests raised. MATING DISPLAYS SOARING PENDULUM FLIGHT DIVING AND Flying in thermals Performing undulating CLAW PRESENTING high above the nest. manoeuvers in the air giving croaking calls, close to the nest. During pendulum flight, one bird sometimes rising 500m or more dives at the other with its feet outstretched, in thermals while the second bird turns and present its claws. GREETING DISPLAYS While performing the display, the bird’s lower jaw vibrates making a repeated guttural croaking sound like a sawmill. UP-DOWN BOWING DISPLAY The up-down bowing display is performed by a bird at the nest on seeing its mate at a distance or on arrival. The Secretarybird’s body is tipped forward, head repeatedly raised and lowered while it’s breast feathers are erect, tail fanned and held almost vertical. It will peck at the nest lining during the display. Find out more on the BirdLife South Africa website at https://www.birdlife.org.za/what-we-do/environmental-education/bird-of-the-year-2019/ or visit the Facebook page @BirdLifeSouthAfrica Design and Illustrations: Chrissie Cloete @ChrissieCanDraw SOURCES: Dean, WRJ, Ryan PG (eds) Roberts - Birds of Southern Africa (VIIth Ed) Cape Town: The Trustees of the John Voelcker Bird Book Fund. I Hofmeyr SD, Symes CT, Underhill LG (2014) Secretarybird Sagittarius serpentarius Population Trends and Ecology: Insights from South African Citizen Science Data. PLoS ONE 9(5): e96772. doi:10.1371/- jour- nal.pone.0096772 I Sherman, P. 2007. Sagittarius serpentarius (On-line), Animal Diversity Web. Accessed December 29, 2018 at https://animaldiversity.org/accounts/Sagittarius_- serpentar- ius/ I Whitecross, M.A., Retief, E.F. and Smit-Robinson, H.A., 2019. Dispersal dynamics of juvenile Secretarybirds Sagittarius serpentarius in southern Africa. Ostrich, 90(2): 97-110. Lorem ipsum Roosting: Mewing calls when roosting. Territorial Displays: Secretarybirds will defend their nest and show territorial displays like soaring and pendulum flight displays and wing-open displays. They will pursue any intruders with an open-wing display along the ground with wings held above its back. If the intruder is overtaken, the bird will jump above it, striking downward with its feet. After the intruder withdraws, the pair will walk around each other with crests raised. Wings-open display: used in greeting. Soaring and Pendulum flight displays: Used during courtship. The birds fly high, soaring together near the nest sight, giving croaking calls, rising 500m or more in thermals, then performing undu- lating displays. One bird sometimes dives at the other with its feet outstretched, while the second bird might turn and present its claws. Up-down bowing display: Performed at the nest on seeing its mate at a distance or on arrival. While performing the display, the bird’s lower jaw vibrates making a repeated guttural croaking sound like a sawing mill. Up-down bowing displays are performed at different intensities: - High Intensity – The bird’s body is tipped forward, head repeatedly raised and lowered to full extent, breast feathers erect, tail held almost vertical, fanned to show grey, black and white pattern, elongated central rectrices, and white undercoverts. It will peck at nest lining during display. - Lower intensity – When the pair is together on the nest, they only make bows, with their bodies horizontal and their tails depressed below horizontal..