A few weeks ago while paddling with a friend at Falls Lake, he noticed what appeared to be tree goo stuck to the branches of many of the partially submerged trees that line the lake. Having never noticed this before, we guessed that maybe it was some sort of fish eggs or possibly sap running out of the branches. It was quite solid to the touch, almost like an extra thick version of ballistics gel like you might see on Mythbusters, so the egg sack theory didn’t make too much sense and since it was on a variety of trees(and I’ve never seen it before) the sap theory didn’t make much sense either.
After seeing this for a few weeks and wondering what it was, I finally got around to googling it and it appears that what we were seeing is a type of bryozoan bloom of a species called Pectinatella magnifica. Bryozoan’s are a very small aquatic filter feeder and this particular specieis of fresh water bryozoan is commonly found in waters East of the Mississippi, but has been cropping up in a number of non-native places, such as Washington.
Scientists are unsure of what impact these might have in areas where they do not normally appear and they can only survive in water that is around 60 degrees Fahrenheit, so as we see temperatures increase due to global warming, they are likely to appear in places that they would otherwise not survive. They are filter feeders, so keep the water clean, which can be a good thing, but also has an impact on other species that live in the water.
It is possible these have always been here and I just never noticed them before, although I feel like it is a somewhat new occurrence and they are EVERYWHERE around Falls Lake!
Some Pictures: