In early September, a Golden-tailed Woodpecker began work on a nest hole in a dead snag of the tall Anthocleista grandiflora tree in our front garden. Great news, I thought, as I’d finally be able to follow the breeding cycle a woodpecker here at home. Within a few days, however, the woodpecker had been noticed by a family group of Black-collared Barbets and they soon forced it off, took over the site and finished the hole.
By late September, the barbets were in full residence and the alpha female is thought to have laid. These barbets are co-operative breeders, with two or three offspring from the previous clutch typically remaining with their parents to assist in raising the next brood. Quite why they have evolved this strategy was to become abundantly clear in the weeks ahead.
In early October, a Scaly-throated Honeyguide flew over my head to land in a small tree in our garden. It was reluctant to fly when I approached it and I thought that to be rather odd. But the next day, there was an outbreak of hissing, rasping and chattering at the barbet nest hole and I saw what was presumably the same honeyguide (or its mate) being viciously set upon by the barbets.
Like cuckoos, honeygudes are brood-parasites, laying their own eggs in the nest of another bird and leaving them to raise the resultant ‘orphan’ as foster parents. For honeyguides, their hosts are barbets, bee-eaters, woodpeckers and other cavity nesters. So, the Scaly-throated Honeyguide was trying to lay in the nest of the barbets, but with one barbet in the nest and three others on patrol, it was no easy task. For the next couple of weeks, I became accustomed to the regular pursuits and angry vocalisations around the nest hole.
Then, at about 15h00 on 21 October, I was observing the nest hole when something very surprising happened. A Scaly-throated Honeyguide appeared and was immediately set upon and subjected to a tirade of abuse from the barbets. Its white outer tail feathers flashed past me as it dived for safety. The likely strategy is that the male honeyguide shows itself to the barbets, lets them come after it, and thus provides its mate with a chance to sneak in and drop an egg. But there was still one barbet (I suspect the alpha female) at the nest entrance. A second honeyguide did appear and this prompted the hole-bound barbet to go on attack. Now the hole was completely unguarded and – to my amazement – a Lesser Honeyguide appeared from nowhere, entered the hole and was out and gone before I could say “it’s laid an egg’! Seconds later, the barbet was back at the hole seemingly oblivious as what had just happened.
Had the smaller Lesser Honeyguide been watching the whole situation, waiting for such an opportunity, or had it -along with the Scaly-throateds – been harassing the barbets all along? I’ll never know.
The next day, 22 October, brought high drama. I’m working away at my desk, with the front windows wide open to keep the studio ventilated. I hear the usual wild screeching outside (barbet chasing honeyguide) when a little brown bird bursts into my studio, followed by one angry barbet! Both hit the big window on the opposite side with an awful thud . . and then crash to the floor. But what proved to be a Lesser Honeyguide was up quickly then flew onto a windowsill where I was able to grab it. Now, with the honeyguide clasped firmly in one hand I went down to look at the barbet which seemed to by dying with a broken neck. I quickly photographed the honeyguide (not too easy with one hand!) before releasing it. It flew off strongly. I then went down and picked up the limp barbet and put it in a shoe box – it seemed to have some mobility in its neck but was clearly concussed. I put the lid on the box (birds calm down in small dark places) then left it alone for about 15 minutes. I then carried the box out into our tree house (right near the nest hole) and lifted the lid. The bewildered barbet looked at me groggily but was now able to fully rotate its neck. Five minutes later it was up and off, joining its clan in the ongoing war with the honeguides.
But here’s the thing:the barbets do not know that they are no longer defending their own offspring. There is a baby honeyguide soon to hatch and to be fed as if it were their own.
Turaco Wood, Nelspruit, South Africa. October 2012