Have to agree with the last couple posts...that being said, we have saw what you are seeing in our pond before, but never really associated it with breeding. The "leftovers" when there is a breeding frenzy going on is usually very white, like the pics above. Can't say we have ever had anything golf ball size, but it is definately more solid white, not so transparent. We usually find globs stuck on plants or prefilters on the pumps. Are there bite marks on the female? Maybe it's some slim coat from him chewing on her?