Crossing the Causeway over the Sand River on our way back to camp, we noticed something unusual.
There is an island of trees in the middle channel of the river here where many birds build their nests. There are Grey Herons, Thick-Billed Weavers, Lesser Masked and Village Weavers and eve the occasional Black-Crowned Night Heron.
On this particular morning, sitting at the main weaver colony was a troop of vervet monkeys.
One by one we noticed the weavers mobbing and actually hitting the vervet monkeys on the head. We thought it was quite strange until we saw one of the monkeys stick its whole hand into a nest.
Given how much effort a nest takes to make, this in itself was sad to see…
The male village weaver will build around three to five nests, using strips of grass or reed blades, he replaces any nests that have turned brown or ones the female rips apart that she does not approve of.
They will regularly build their nests above the water to help protect them from land predators. The building of a nest can on average take up to 15 hours, so it must have been horrific for the weavers to sit and watch this take place.
The monkeys weren’t just ripping up the nests though, they were going after the chicks!
As the monkeys were methodically checking each nest the weavers were dropping on them, pecking at their heads, hoping in vain to deter them. Some of the monkeys got lucky and pulled out a chick and stored the meat in their cheek pouches.
Although we generally see vervet monkeys foraging on the flowers of a sausage tree or on the fruit of a fig, they are actually omnivores, meaning they eat both plant and animal food sources. They are also very opportunistic and thus it is not too surprising that they were looking through the nests for any chicks or eggs for a high protein meal. It’s just something I’ve never seen before.
During this time of year there is an abundance of chicks and eggs around, and birds are having a tough time protecting their offspring from all types of predators from snakes to monkeys.
Some species they have really camouflaged nests like the Chinspot Batises that James Tyrrell posted about a few weeks ago, or they have built them in inaccessible areas.
Unfortunately for the weavers in this particular sighting, whilst building nests out over the water may have protected them from some predators, it wasn’t enough to stop the incredibly agile and dexterous monkeys.