And Sargassum Takes Over Another Area

[Eric Sedletzky]

I think many of the scientists at CDF&W mostly understand the problems but my belief is they are hog-tied by the bureaucracy, rules & regs and lack of funding.

The lack of funding part would be easy yo overcome in many ways. The first would be to allow volunteerism without a lot of red tape and bureacratic regulations. There is no reason why the people in charge couldn't set up a call to certified divers to help pull weeds on selected weekends, just like coastal clean up days. Maybe an hour long seminar/ briefing on what they will be doing, sign a waiver, and get to work.
Instead the "officials" claim they will handle it and it never happens.
What do they do to you if you decide to go pick sargussum on your own?

 

[drrich2]

Is there any role similar to that of lion fish hunting, where reducing the invasive 'load' in limited areas might offer a reservation for native species to gain some population protection?

With lion fish, we know they're in the Caribbean permanently, and can't be eliminated, but #'s can be radically set back from frequently dove areas.

Would targeted sargassum elimination help maintain some kelp populations, and those species that rely on kelp?

Richard.

 

[Eric Sedletzky]

Is there any role similar to that of lion fish hunting, where reducing the invasive 'load' in limited areas might offer a reservation for native species to gain some population protection?

With lion fish, we know they're in the Caribbean permanently, and can't be eliminated, but #'s can be radically set back from frequently dove areas.

Would targeted sargassum elimination help maintain some kelp populations, and those species that rely on kelp?

Richard.

I'm not trained in invasive marine organisms, but since they are hand pulling these weeds and claiming success in their transects then it would seem to me to be a viable method to slow down the invasion and maybe keep in it check.
Part of the problem is the water is unusually warm right now because of El Nino, and until water temps drop into to mid 50's the kelp won't grow. The colder water will also slow or stop the sargassum growth.
Up here in Norcal we don't have any sargassum but we also don't have any kelp right now due to warm water. We have Bull kelp which is different from giant kelp found in Socal. The water needs to get back down to the 40's and low 50's in order for bull kelp to be happy. But at least it's still too cold up here for sargassum. The poor abalone are not happy right now.

 

[drbill]

What do they do to you if you decide to go pick sargussum on your own?

I think they may waterboard ya.

Seriously, nothing so far as many of us pull it but the density is so thick some years that I doubt we could even remove it from just our dive park (a Marine Protected Area).

 

[drbill]

Part of the problem is the water is unusually warm right now because of El Nino, and until water temps drop into to mid 50's the kelp won't grow. The colder water will also slow or stop the sargassum growth.

You're right that the cold water (and generally south-flowing currents) along the central and northern California coasts will limit the spread of Sargassum in that direction. However, it actually is a cool water alga. In Japan they are having problems because the warmer water (apparently from elevated ocean temperatures) is causing it to thin out and die there where it is an important commercial crop. Here we see dense Sargassum following very warm summers, but I think that is primarily because there is no giant kelp canopy to overshade it.

 

[Eric Sedletzky]

You're right that the cold water (and generally south-flowing currents) along the central and northern California coasts will limit the spread of Sargassum in that direction. However, it actually is a cool water alga. In Japan they are having problems because the warmer water (apparently from elevated ocean temperatures) is causing it to thin out and die there where it is an important commercial crop. Here we see dense Sargassum following very warm summers, but I think that is primarily because there is no giant kelp canopy to overshade it.

So it's opposite from my understanding about cold/warm water and sargassum growth. If there is a commercial market maybe that's something to think about?
If Japan is running low maybe there could be an export opportunity?
It seems that whenever there is a commercial industry with certain sea foods/products there is an automatic crash in the targeted organism. In this case maybe that's a good thing?
You know how it is with commercial fishermen and making money, they'll find every frickin' strand!

 

[drbill]

I had the same interpretation early on.The Sargassum does dominate during periods of warm water but apparently it is because giant kelp canopy is usually greatly reduced, allowing more light to penetrate the water (we're even seeing it down to 100 fsw here). It is an annual with peak growth during the cooler late fall, winter and early spring.

I've worked with two groups of scientists from Japan and tried to get them interested in harvesting ours to transport to Asia, but I think the economics wouldn't work. Perhaps if the domestic market here could be developed we might have a chance. Over there it is used as food, fertilizer and for biofuel production.

 

[geoff w]

I think they may waterboard ya.

Seriously, nothing so far as many of us pull it but the density is so thick some years that I doubt we could even remove it from just our dive park (a Marine Protected Area).

If we pull it up but don't get it all out of the water, will that cause it to spread further? Or pulling it out and letting it float around in the water has no bad effects? Last weekend I was so tempted to just rip it out (even if it was in an MPA) but thought better of it because of possible unintended negative consequences

 

[drbill]

Geoff... the situation on the mainland may be quite different from here. If you pull it out while it is reproductive, it might drift to another location and establish there. Here on the island it is everywhere on the leeward coast (and windward side from what I've been told). When we rip it out, it does drift at the surface. I wonder how long it drifts... hopefully not long enough to cross the Channel. I'd like it if it sank to the bottom of the San Pedro Channel to 3,500 fsw and died a terrible death under extreme pressure!

 

[islanddream]

What's really sad here in SE Florida is we can't find any Sargassum! I volunteer at the Loggerhead Marinelife Center and we have baby sea turtles that were born last nesting season that got washed back to our beaches because of the crazy weather this winter. We are not allowed to release the baby turtles anywhere except on the Sargassum weed line (baby sea turtles live on the weed line for many years as it's rich in food and helps camouflage the turtles) so we are keeping them in tanks at our facility. Since nesting season has started in SE Florida (we already have 40+ Leatherback nests and 4 Loggerhead nests.....had over 16,000 sea turtle nests last season on the 9.5 miles of beach we monitor) we are concerned that when the nests hatch out the new sea turtles won't have a weed line to get to. I know Playa del Carman and other parts of the Maya Rivera had a huge problem last year with tons of Sargassum on their beaches. So much that people were checking out of hotels because they couldn't swim or sunbathe. So for us, Sargassum is critical. Please send it our way!