My guess at a first glance would have been a branch in which had a disease called "Wetwood Slime" with a rather rapid growth due to have been floating in the water, but after seeing pictures of Bryzoan Colonies, that explanation seems the most plausible.

No its not. The op said that is a stick he put through them to hold them up, not a spine.

I think it looks like some fish or frog eggs. They are attached to what looks like a piece of rope, I found stuff like that on the bottom of my grandpa's boat.

dude its a freaking egg lol i have seen some in a museum.

probably sand haha
i dunno..
probably was once alive
it must be an out of water animal right?