Baby spiders.

[Tim Abbott]

I don't know what these are.  I was kayaking 1000 islands in Cocoa Beach today saw this web in the mangroves & thought they were egg sacks, in a blink of the eye they dispersed all over the web.  The area is still pretty devoid of birds since the fishkill last spring, saw a couple ibis, 2 osprey & a belted kingfisher.

[Ira Runyan]

I guess that you got the attention of the baby spiders! They must have felt vibrations of the web that alerted them that you were in the area. 

[frank]

Neat shots!! You must have been in one of the mangrove tunnels to be that close.

[Tim Abbott]

Hi Frank, I do that every time I go there, saw a little snake earlier in one. The water looked pretty clear, mangroves looked healthy I could see my paddle end down about 2 feet. I never thought of that, Ira, but I was holding on to a branch & probably jiggled them severely.