I didn't notice it till you mentioned it but I think it might be a bat or bird flying just above the water maybe getting mosquitos or other insects would be my guess.

Yes! It´s so fast! I dont know what´s it...

Did anyone see something "swimming/darting" through water at first of video?

I think it´s a Baboon too!

Hi,

I have listened to this a few times and I think it might be a Baboon call.

I listened to this twice we can rule out bush buck as we never see them at nk it could be either a leopard behaving territorialy or a male baboon that is my gues