27 November 2011

African Finfoot and Whitebacked Night Heron Breeding in Umzumbe

A few weeks ago I received a phone call from a Richard Hulley to say that his son Brangan had found the nest of an African Finfoot on his farm dam in Umzumbe. The bird has been present on the dam for ten years that I know of and possibly a lot longer.
African Finfoot incubating
The two of us investigated and found the nest on an Island in the dam, and low and behold it had chosen the one island that has a bridge leading to it. We moved around the dam and crossed the bridge and saw the nest with one egg in it (normally the clutch is one or two eggs), virtually nothing is known about the breeding habits of these birds, so this would be a good chance to record and learn something. The nest is in the branches of the tree over-hanging the water, at a height of about 50cm above the water. This is done so that if there is any disturbance the female can quietly slip off the nest into the water and swim away to avoid giving the nest location away. We also found another nest in the tree about 1m above the water and with four white eggs in it, the adults of which had flown off when we arrived on the island. 

African Finfoot egg

Whitebacked Night Heron eggs
Ten days later I went to check the progress of the nests and walked across the bridge, which this time after the recent rain collapsed on me when I got close to the island, so there was me up to my chest in water, binocs around my neck (now totally submerged), camera in its bag with phone and keys for save keeping, also in the water. A quick swim to the island and everything got laid out to see what damage had been caused, luckily camera and phone were still relatively dry and the binocs are gas filled. However the birds on the nest quickly disappeared with all the commotion. I investigated the Finfoot nest first and found the egg still intact; I then checked the other nest and found three chicks and one egg. Now to sit patiently to see what would happen. Firstly the Finfoot came back and continued incubating allowing me to take a few pictures, then after what seemed forever one of the other birds flew back and I was able to identify it as a Whitebacked Night Heron, so we have a new breeding record of this most elusive and rarely seen birds. 

Whitebacked Night Heron chicks
The trouble came three days later when heavy rain fell at the dam with 75mm falling overnight on Friday. On Saturday I went to have a look without going onto the island as a good viewing site had been found looking straight at the African Finfoot nest, however the Whitebacked Night Heron nest is not visible. The water level in the dam had risen to the point of almost touching the Finfoot nest, the nest has been abandoned and was at an angle of 30deg off horizontal, the only hope now is that the egg hatched on the Wednesday or Thursday as being a water bird the chick is able to swim at two days of age. My plan was to borrow a small boat and conduct further investigations once the weather improved. 

African Finfoot nest after the rain
A week later the rain haf stopped so I went to the island after borrowing a small boat. I paddled to the island to avoid too much noise and was shocked at what awaited me, The Whitebacked Night Heron nest is also devastated and there were no sign’s of the chicks so we must assume that they have perished, Roberts 7 gives the nestling period at around 40 days, and records that the chicks can climb around the tree at about 21 days, these chicks are only 11 to 12 days old, and no sign could be seen.
Whitebacked Night Heron nest after the rain

1 comment:

  1. What a pity Andrew. It is sad that the little ones didn't survive and sad that you wont have the chance to study their breeding behaviour. I really hope they come back and try again and that you (and they) will have more success next time.

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