We allowed plants to take over our water reservoir (former swimming pool) hoping that they would slow down the evaporation. Whether water plants do this is probably debatable but they did enable the African clawed frogs (Xenopus laevis) to multiply really well.
As the frogs are happy to stay in this small “wetland”, the population reached large numbers and, although they devoured all the guppies placed there for mosquito control, the population has not yet crashed. They are also tolerated as they are rather quiet, unlike other visitors we have had in past years.
Luckily, attracted by the “fast food” on offer at least one (I am not good in identifying individual birds yet…) hammerkop[1] became a frequent customer. It walks around the pool stalking the frogs that it catches them often. It is nice to have these birds in the garden and we hope that some of them will eventually come and nest here as there are a few trees that would be able to hold one of their humongous nests.
On a Sunday in January last, before we went for lunch to a nearby place, a hammerkop arrived. It was late morning and it perched by the pool’s edge with its sights fixed on the water plants, undoubtedly waiting for its prey. We watched it for a while but it did not move so we left it to find its food while we found ours.
After a nice lunch we returned home (for a siesta…) and found the hammerkop still there. It had caught a frog larger than anything I had seen before. It was already dead and the bird was busy “hammering” it against the floor. It seemed that the technique was to break its bones to be able to swallow it and it was really going for it!
We watched the bird “tenderizing” the frog for about one hour until it was totally limp. At that stage the hammerkop attempted to swallow it a couple of times and failed so it decided to wet it and try again but it was still a “mouth full” and it was not able to gobble it up completely so, after swallowing about half, it was forced to expel it out or it would have choked!
Eventually, after wetting it again, the bird had another swallowing attempt that nearly succeed but clearly the frog was larger than its throat so it came back out again. This time the bird, probably fed-up (my interpretation!), just dropped it in the water and left!
I thought that this was a real waste of a meal and, to avoid the toad rotting inside the pool, I fished it out to dispose of it. While getting it I noticed that despite all the hammering the carcass received, the skin was not broken anywhere, an indication that the rather large beak of the hammerkop is not used for piercing and also that it was “all or nothing”!
[1] Scopus umbretta
A Bushsnob in Africa 