If I told you that
mangrove kingfishers fly into trees at full speed to make a nesting
hole, you would not believe me, so watch the video.
This mangrove
kingfisher (Todiramphus chloris) is nesting in a dead
Sonneratia tree deep within a tall stilt mangrove swamp. At
intervals of approximately one minute, the kingfisher flew into the
tree with a run up of approximately 10 m. The bird was in a frenzy
to make the nest hollow as quickly as possible. A female was watching. Mangrove kingfishers
are quite large at about half the size of a kookaburra, so it is
quite surprising that they can survive such an impact, let
alone repeat it. In the video, the kingfisher passes through the field of view in a single video frame. I saw about six hard runs at the tree. Between runs, the kingfisher flew around the tree, landing on stilt roots, calling and displaying to the female.
The tree that the kingfisher was chiseling away at also has a story. It belongs to a species that only colonises the seaward edge of mangrove swamps. However as the mangroves prograded, it became stranded and then overshadowed by stilt mangroves (Rhizophora spp.) and died. Beetles drilled into the tree and spread fungal spores which grow into the white fungal coating that the beetle larval eat. Tasty beetle larvae attract striped possums and this tree was cratered with striped possum pits when I first recorded the tree in June 2017 for the striped possum post. From my experience in locating fig parrot nests, I know that there is a window of time between when the tree becomes soft enough for a bird to make a hollow and the tree developing vertical cracks which pipe water down inside the timber or the tree simply falling over. This window probably lasts for several months only. Mangrove trees also tend to be quite thin and it is would be hard to find one with sufficient diameter for a nest. Sometimes a kingfisher will hollow out a tree that is too small and will drill clean through the tree or create cracks that allow chunks of wood to fall away. Looking at the hole, I suspect the female will reject it. The mouth of hollow is just too wide and it appears that part of the roof of the hollow has fallen away.
The tree that the kingfisher was chiseling away at also has a story. It belongs to a species that only colonises the seaward edge of mangrove swamps. However as the mangroves prograded, it became stranded and then overshadowed by stilt mangroves (Rhizophora spp.) and died. Beetles drilled into the tree and spread fungal spores which grow into the white fungal coating that the beetle larval eat. Tasty beetle larvae attract striped possums and this tree was cratered with striped possum pits when I first recorded the tree in June 2017 for the striped possum post. From my experience in locating fig parrot nests, I know that there is a window of time between when the tree becomes soft enough for a bird to make a hollow and the tree developing vertical cracks which pipe water down inside the timber or the tree simply falling over. This window probably lasts for several months only. Mangrove trees also tend to be quite thin and it is would be hard to find one with sufficient diameter for a nest. Sometimes a kingfisher will hollow out a tree that is too small and will drill clean through the tree or create cracks that allow chunks of wood to fall away. Looking at the hole, I suspect the female will reject it. The mouth of hollow is just too wide and it appears that part of the roof of the hollow has fallen away.
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| The kingfisher hollow, photo taken at night when kingfisher was away. |
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