This year, I am amazed at how much barnacles and growth I have on the bottom of my boat. I'm located on the Sassafras River, Upper Chesapeake, MD. (Fresh water river) Could this be due to global warming? Is the river water warmer than in the past? Any marine biologists on this forum able to chime in? I hauled out in the spring for some light maintenance and the yard power washed the bottom. There was plenty of anti fouling ablative on the bottom when it went back in. Anyone?
MARINE GROWTH
- Thread starter twodzusfittings
- Start date
Some bottom paints lose efficacy when dried out. As you were hauled for a period for maintenance, that’s a likely cause.
As is lack of use - a stationary object tends to accumulate growth.
As the average temp change over the last 100 years hovers around 1degreeC, you can draw your own conclusions as to the effect that has.
As is lack of use - a stationary object tends to accumulate growth.
As the average temp change over the last 100 years hovers around 1degreeC, you can draw your own conclusions as to the effect that has.
Population blooms, if that is what you are seeing an effect of, are usually correlated with increased food supply. For barnacles, which are filter feeders, that would be plankton, mostly phytoplankton but including bacterioplankton and detritus (bits and pieces of degraded algae). Phytoplankton blooms follow an increased supply of nutrients coupled with abundant sunlight. The most important nutrients for phytoplankton growth are nitrite, nitrate and ammonium. Most of this comes from in situ (in the local place) nutrient recycling via bacterial decomposition of detritus and dead organisms plus reduction (fixing) of atmospheric (diatomic) nitrogen (N2) to ammonium (NH4+), which leads to production of nitrite and nitrate. The nutrient limiting nitrogen fixing (done by blue-green algae) is typically iron. The more iron in the water potentially the more the production of ammonium leading to more nitrite and nitrate; so the more phytoplankton, the more food for barnacles; thus more barnacles, up to a point.
It’s true that warmer conditions will speed up most chemical reactions, including metabolic and growth rates of “cold blooded” fauna but their food must be there first. Population blooms come and go in the marine/aquatic habitat, as elsewhere, both regularly and episodically. They are natural events, but they likely do include some anthropogenic factors in some instances, etc. However, I doubt your issue could be traced to “global warming.”
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Sure it could be temperature… Climate is not a sudden change agent. It takes decades of weather changes to show a sudden change in the environment. From the way you described the issue, it sounds like this is a more sudden (24 months) type of change to your boats bottom. If it is a concern I would look towards upstream development that might be causing an impact on the stream. You could start with stream temps. Do the local jurisdictions manage water sensors on the river? In addition to temperature you should look at chemical run off. Fertilizers from housing developments. I note that google shows a major solar panel farm in the Sassafras River water shed near the Square Dog Ranch. They have denuded the fields to install the panels. Not sure if they used herbicides.
The river appears to be a popular area with housing development along the river. All of these sites generate stormwater runoff. Where does the runoff end up? Is it treated to remove the fertilizers and other contaminates or is it dumped into the river.
It would be wonderful if we could name one thing that is a cause, then we all could get focused on that culprit. In reality it is often many things that together create a cumulative change to what we call the “norm”.
The river appears to be a popular area with housing development along the river. All of these sites generate stormwater runoff. Where does the runoff end up? Is it treated to remove the fertilizers and other contaminates or is it dumped into the river.
It would be wonderful if we could name one thing that is a cause, then we all could get focused on that culprit. In reality it is often many things that together create a cumulative change to what we call the “norm”.
My guess is that it wasn’t the temperature but rather the dry weather, especially early in the season, that allowed them to take hold. Up here in the northern bay the water is usually fresh, but May and June were so dry that salt water made its way all the way up the bay. Dolphins were sighted as far north as Elk River by @dLj and others; in other recent years I haven’t heard of them being much north of the Patapsco. I haven’t seen any barnacle growth in the Susquehanna, but you’re just a little south of me and maybe it was just salty enough to be over their threshold.
Based on my less than zero knowledge of marine biology, I would say that 
sometimes happens. Normally my underside has little to nothing to offer and looks like this after not moving all winter
Then in 2018, it decided to look like this for no reason whatsoever
Different type growth moved into the neighbourhood that year although they still didn't like the ablative on the hull.
Wait until next year and see if there's a difference before you get into anything like weekly bottom scraping.
sometimes happens. Normally my underside has little to nothing to offer and looks like this after not moving all winterThen in 2018, it decided to look like this for no reason whatsoever
Different type growth moved into the neighbourhood that year although they still didn't like the ablative on the hull.
Wait until next year and see if there's a difference before you get into anything like weekly bottom scraping.
Generalities are always wrong sometimes.
Some ablatives are supposed to be limited to 30 days dry-out. Others require buffing to remove oxidation prior to launch if kept out too long.
West Marine PCA Gold. (large amount of copper in %) Boat was hauled in the AM and splashed in the PM.
I am impressed with the answers posted. I now understand how and I can see how local farming, housing developments and the weather all have their affects in the ecology of the water. Thanks for all the responses. One more season in the water then haul out again!
I am impressed with the answers posted. I now understand how and I can see how local farming, housing developments and the weather all have their affects in the ecology of the water. Thanks for all the responses. One more season in the water then haul out again!
I am unaware of any ablative paint that cannot withstand prolonged exposure to air. And neither are you, apparently.
micron CSC ablative among others. glad to helpI am unaware of any ablative paint that cannot withstand prolonged exposure to air. And neither are you, apparently.
That you say a thing doesn't make it true. To wit, Micron CSC is formulated so that it can be hauled for the winter and relaunched the next season, without the need for recoating. Further, new CSC has no maximum dry time before splashing. All of this information is readily available on the Interlux web site. However there is no mention of a "30 days dry-out."
I challenge you to provide some documentation backing up your claim.
From the horse's mouth:
Hello Matt,
Micron CSC is an ablative so 3 to 5 months is ok, but if you are out long term like half a year or years, then you may have to do something prior to relaunching.
Best regards,
Joe Hernandez
Technical Support Representative - Yacht
Marine, Protective and Yacht
International Paint LLC.
6001 Antoine drive
Houston TX,77091
:Hello Matt,
Micron CSC is an ablative so 3 to 5 months is ok, but if you are out long term like half a year or years, then you may have to do something prior to relaunching.
Best regards,
Joe Hernandez
Technical Support Representative - Yacht
Marine, Protective and Yacht
International Paint LLC.
6001 Antoine drive
Houston TX,77091
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One source says no maximum dry time before launching. Another source says that if it's longer than half a year before launching, you better get out there and "do something." Do what ? Do where ? When ? / Why ?
Good Lord man, which is it ?