In an earlier post, Angie Ng described in detail how a male Scarlet-backed Flowerpecker (Dicaeum cruentatum) deposited a string of sticky seeds on her sui mei (Wrightia religiosa) plant thus:
“After comfortably positioning itself transversely across the branch, it turned its head… then it awkwardly stretched apart its legs, lowered its little body for a second or two and with a swagger, it moved a few steps to the left. With that quick swaggering action it wiped off a string of six gluey mistletoe seeds onto the branch of my sui mei.”
Now, Chan Yoke Meng has documented another behaviour by a female Scarlet-backed Flowerpecker excreting Macrosolen cochinchinensis seeds. These mistletoe seeds were excreted one at a time. Each seed was enclosed within a tough gummy substance that remained unchanged after passing through the bird’s alimentary canal. The seeds were excreted in a string – any one seed attached to the one before and the one after by this gummy substance.
The bird had no difficulty expelling the seeds from the its vent, that is, its posterior opening. The problem was to get rid of the seeds after they emerged. With all the gummy substances around, the seeds remained stuck to the bird. In Angie’s case, the bird rubbed its posterior end on the branch it was perching on.
Meng’s observations show the birds actively removing the sticky seeds with the help of its bill and feet (of course, not using both feet at the same time, ha ha). The action was rapid and he missed documenting the most interesting scenes. However, he managed to record the bird entangled with strands of gum stuck to its bill and feet (see panel above). Two seeds that the bird managed to remove remain stuck to the branch behind it. Note the translucent globs of gum still attached to the seeds.
Chan Yoke Meng