Fish Spawn Issue

In the Oceans, the fish spawn rarely in some spots then later, lots of them spawn then dissapear after a few minutes. I dont know why this is happening. This happends with Salmon and at times, Cod. This isn't a big issue, but it annoys me when I see them spawn before I go to bed, and when I wake up, they are all gone.
I noticed that it started around the Buzzy Bees Update.