30.11.09
Dear Colin
Sorry for delay in reply; I normally reply fast.
Thank you. I feel very encouraged.
Lentolia Farm, Naivasha White-bellied Tit data not yet published, despite suggestion from Don Turner that it should be. I must get on with it. Without intense survey of my copious White-bellied records, the following may interest you: 6 tit boxes were used, 8 clutches were laid totalling 23 eggs, average clutch size 2.9. Of those 23 eggs, only 6 young resulted, 4 known to fledge and 2 probably did. Of the remaining 17 eggs, 3 were known to have been parasitized, probably by Greater Honeyguide and 8 were almost certainly spoiled by unknown smaller species of honeyguide as egg damage indicated entry of box through tit sized hole. One clutch of 2 eggs was deserted.
The Greater Honeyguide incident is fascinating. A honeyguide egg was found in a White-bellied nest of 3 eggs, and the honeyguide egg was damaged. It was removed and measurements showed Greater. The box entrance hole was suitable for tits, not Greater Honeyguides, so the egg must have been placed in the box by beak and maybe damaged at that time. However, had it hatched, it would never have been able to get out of the box! 7 days after it was found the tit eggs were fine, and a tit left the box 3 days after that. 8 days later the box contained only half a tit egg shell. Maybe a smaller honeyguide species had done that.
At Lentolia over 16 months, clutches in various stages of development were found on 28 April, 6 may (2), 30 May, 24 June, 9 July, 22 August, 3 September.
At Green Park there were 3 clutches (so far) in 1 year, all 3 eggs, clutches early October, 19 October and 11 January. Feathers on the January clutch almost certainly indicated the sitting bird was killed on the eggs. Lentolia is about 100 acres; my garden now about 4 ½.
There was one Lentolia woodpecker box of extraordinary interest. Nubian Woodpeckers moved in and had eggs. When the box was checked it contained one 64g baby Scaly-throated Honeyguide which was colour ringed and seen out and about with its foster parents much later. A month after ringing, the box contained 1 dead adult male Nubian, on its back, very dried out and long dead weighing only 46g. This was removed.
A month later the box contained a White-headed Barbet on 3 eggs, 1 of which seemed to be a Lesser Honeyguide. A week later the honeyguide egg had a large hatching hole, but appeared dead.
There were still 2 barbet eggs. The next day the barbet was sitting. 3 weeks later staff saw a barbet looking out and the next day the nest was checked and had nothing. The nest was spotless so it probably never had young. 9 days later the nest was still empty, then 13 days after that a female Nubian was looking out of the box and was found to have 4 eggs. All seemed to be woodpecker. After another 5 days she was still sitting on 4 eggs; 2 were dark, one was possibly dark and one was clear. All were the same size. 4 days later the male was looking out and the nest contained one baby, day old. The shell was removed and kept. 8 days later the young, a honeyguide was there but all 3 eggs were gone. 2 days after that the young which was scaly-throated was 39g and after another 6 days it was 60g and colour ringed a week later. The box was now unused for 5 ½ months when, on 17 June a female Nubian was looking out and 2 days later was sitting on 2 eggs. But after another 6 days the box was empty and new woodpecker holes had been made in the side and centre of front. These were Nubian sized holes. The box was ruined, very sad after such a dramatic and hectic career.
Grahame Dangerfield
Hon Director
The Grahame Dangerfield Wildlife Trust, UK