Posts by KatFish:
Flamingo Tongue Flood
March 14th, 2010
I know I make a big deal about knowing what you see “down there,” studying books, knowing what fish are where, hang out with who, are in what abundance normally. And I’m hoping that all I’m doing is collecting baseline data by counting fish when I do REEF surveys, that I’m not actually going to find a lionfish, or that I’m not actually going to see something that makes me pause and say “well, that can’t be right…” But every once in a while, something like that happens.
I’ve been doing some traveling, had the fantastic opportunity to travel and dive from St. Thomas all the way up through to Miami. Dove some beautiful places that not many other people can claim to have dove – Cay Lobos for one (if you ever have the chance…GO!) and saw a huge range of species, lionfish included unfortunately, but only from Puerto Rico north (though I hear they’ve been sighted in the BVIs!). Another thing I noticed is pictured to the left. Which, as I said, made me pause.
Flamingo Tongues (Cyphoma gibbosum) are gorgeous, people can’t really argue with that. It’s pretty interesting how little we know about them. We know that they are a gastropod, or a snail of a sort; we have a good idea that they like to feed on soft corals like the gorgonian pictured above and the sea fan below; the spotted pattern you see is not the shell, but the soft mantle of the organism living in the shell; personally, I think that octopus like to snack on them as I often see the shells scattered about the openings of known octopus dens in Saba. Other than that I can find very little on what else eats them.
Technically speaking, flamingo tongues can be categorized as parasites, munching on soft corals and giving nothing in return, though not necessarily killing the entire colonial soft coral. But then again, it depends on your definition of the soft coral. If you see the soft coral as one organism unto itself, the flamingo tongue is a parasite. However, if you see the soft coral as a collection of individual tiny organisms called polyps (which it also is), then the flamingo tongue becomes a predator, killing its prey as it goes.
But that’s a debate for another time. My concern is the over-abundance of them on certain dive sites around the Caribbean. I first saw this kind of “infestation” in St. Eustatius (Statia), in the Netherlands Antilles – otherwise known the island next door to me. It was on a weekend dive trip last July (2009) and according to the dive shop it had just started a few months back. When we had visited the previous June (2008) we saw nothing like this at the exact same dive sites. I’m currently waiting on some photos for documentation and additional details.
Like I said, I spent 3 weeks diving over 1000 miles of ocean, USVIs, BVIs, Hogsty Reef, Turks and Caicos, all up the Bahamas, and no where did I see any of this – except Mona Island off Puerto Rico. From the what I’d heard from others who’d dove there more often than me, it was isolated to two dive sites (the names escape me – but 40-60 ft / 12-18m depth on the south side). These sites are where the posted pictures came from. And on doing some research, I’ve discovered they’re also having some concerns in Bonaire, enough that they’re asking divers to do volunteer surveys to track the problem.
According to an article posted on the CEII Research station in Bonaire, the problem may be traceable back to either a) loss of predators due to overfishing that caused a chain reaction and a decrease in predators OF flamingo tongues (doesn’t mention what those predators are…), or b) run off or otherwise addition of chemicals such as nitrogen and phosphorous which act as fuels for algae and “disease-bearing pathogens such as the fungus Aspergillosis sydowii” which has been known to cause Caribbean sea fan mortality. Why the flamingo tongues are more apt to predate on sick sea fans I’m not sure – its not likely that the sick sea fans are less likely to be able to run from the snails. More importantly, the flamingo tongues can also help spread the Aspergillosis.
My question to the diving world is: where else is this happening? Does anyone have any information on flamingo tongue predators? What do you know?
Popularity: 3% [?]
The Great Lionfish Debate
January 2nd, 2010
Lionfish photo taken 2006 in Bimini, Bahamas
For those divers who spend most of our bottom time in the Caribbean, Bahamas, and Southeast coast of the US, the word Lionfish might make you cringe a little. Seeing them underwater tears you apart – half of you wants to run over and stab it to death, while the other half whips out a camera to take a picture of those elegant fins.
I’ve spent about a year and a half listening to people rave about this problem – from experts in the field to passionate divers – and I’m going to try to set the record straight about how the problem started, what’s being done to try to curb the invasion, and if we have any hope for the future. And I’m open to arguments – I’m no expert, just a good listener.
I forget that some people have no idea what I’m talking about, so let me start over. In the early 1990s a handful of sightings of Pacific Lionfish were reported off the coast of Florida. No one thought much of it, aquarium releases, ballast water, they’ll just go away. Until they didn’t.
I spent from 2003-2006 diving daily in Bimini, Bahamas and didn’t see one – out of sights out of mind. In May of 2006 I was DM’ing on a liveaboard in Nassau and my divers came up talking about this crazy fish they saw and showed me a picture. From that day on it seemed like they were everywhere. Bahamas, Florida, even down to the Turks and Caicos. But it’s just a fish, right? No big deal.
In the last two years I’ve learned differently. I’ve spoken extensively with officials at Reef.org, corresponded with some folks at NOAA, and done some of my own research and the truth is scary. According to research and DNA testing, most of the Lionfish that are found all over the Caribbean now can be traced back to about 9 individuals, probably released in the early 1990s (possibly destroyed personal aquariums from Hurricane Andrew in ‘92). The first few years, they’d been reproducing quietly, amassing an army.Then as the years went by they began to appear in greater numbers, firmly establishing themselves on the other side of the world from where they belong. Nothing on this side of the world knows to eat them, and they have quite an appetite – a recipe for disaster in the delicate balance of the marine food chain.
Even in their larval stage, nothing eats these guys. Most fish spawn close to the reef, spewing their gametes a few feet up in the water column, easy meals for egg-eating predators. Lionfish actually spawn almost at the surface of the water, far from where these think to look for tasty treats like fertilized eggs. Females produce 2,000-30,000 eggs in a set of mucus-sealed sacs which guarantee high fertilization rates, and of those fertilized eggs about 80% survive due to low predation of the eggs at the surface.
Post-larval, there are anecdotal reports of specimens found in the stomachs of a handful of Nassau and Tiger groupers, and rumored Lemon sharks, but compared to the Lionfish’s insatiable appetite, that’s not keeping up. In the Pacific there is the species diversity and abundance to support their voracious appetite, but not in the Atlantic. To boot, the Lionfish are quite fond of the taste of our own reef predators in juvenile form: the same groupers and snappers that could potentially prey on the Lionfish later in life.
Their range is quite astounding. Since 1994 Lionfish have been reported as far north as Rhode Island and only a few months ago there were first-time sightings in Bonaire, Curacao and St. Croix. In the Bahamas there are reefs where you’re seeing dozens of lionfish in one small area – and little else in the way of other fish! According to this map from REEF and NOAA there’s not a whole lot of Lionfish-free Caribbean left.
Ok, great, so they’re taking over. Now what? We can’t undo what’s been done; eradicating this species from the Atlantic is at this point impossible. But can we get the invasion under control? Maybe.
1) Report all Lionfish sightings. At REEF.org or NOAA or both. If collection is possible in the area you’re diving, make it happen.
2) Support legislation limiting the import of non-native species to your environment. US residents see HR 669
3) Spread the word. Lots of divers know nothing about this and the more you talk about it the bigger the response will be.
4) I’ve heard one suggestion that exploits the irony of the human-environment interaction and makes me giggle. We’re pretty good at driving species to extinction, right? So why not use that ability to our advantage for once. Promote Lionfish as a delicacy in restaurants, make up some story that the venomous spines enhance fertility (once the venom is removed of course…), something that will encourage the overfishing of Lionfish. Of course this is dependent on finding an efficient fishing method that only catches Lionfish.
For more information, visit REEF.org, read this article by Hare and Whitfield, or use your google-fu.
Resources:
Hare and Whitfield 2003. An integrated assessment of the introduction of lionfish (Pterois volitans/miles complex) to the western Atlantic Ocean. NOAA Technical Memorandum NOS NCCOS 2. 21 pp.
Smithsonian Marine Station at Fort Pierce: http://www.sms.si.edu/IRLSpec/Pterois_volitans.htm
NCCOS/NOAA
REEF.org Lionfish Invasion Program
Popularity: 14% [?]
SCUBA: It’s not just a recreational sport…
October 29th, 2009
I recently had the opportunity to meet an expert in underwater camouflage during part a month long educational seminar on Saba (see www.seaandlearn.org for more information).
I had lunch with one of them and just chatted about his research on camouflage techniques. Somehow frogfish came up and I asked him if he knew why it took them so long to change their colors to camouflage themselves, versus groupers and octopus and so many other species of fish that can switch in a flash. He looked at me dumbfounded and said he never realized they could change color, to which I replied “We have one here on Saba that’s changing from yellow to green as we speak…!”
He shook his head and started praising us – the recreational divers. We are the ones that see so much more than the scientists do. We gather more information, we see the changes, we see the interactions, we watch the oceans transform. We are the world’s ambassadors to the oceans.
It got me thinking: just because we’re “recreational divers” doesn’t mean that we don’t pay attention. But I think we do need to make a conscious effort to be more involved in each of our dives.
The majority of divers are vacation divers – they leave their grueling office job to go somewhere warm where they can shut their brains off and play with the fish. But our brains aren’t really turned off. And with a little engagement we can take a normal every day dive and turn it into a rich learning experience that could possibly help save an ecosystem.
But first you need to build a knowledge base. Knowing that the little black and white striped fish like to chase off divers and leave little hickeys on their legs if they get too close isn’t useful. Knowing that those fish are a type of damselfish called a Sergeant Major and that those big purple patches they are swimming around are egg beds that they are protecting – that’s better information. When you started diving one of the first things you probably learned about were cleaning stations. First someone pointed out those funny-looking purple shrimp to you and told you they were Pederson cleaner shrimp.
Now we had a name for a face. And when we floated nearby for a while we noticed that all kinds of fish would come to these shrimp and let them crawl around in their mouths and gills. The more we watched, the more we learned. Now when you see a parrotfish stop and angle its head up you look for the little tiny shrimp or cleaner fish nearby because you know that posture is a signal to the cleaning station saying “I’m not going to eat you, I just have an itch.” And we know that instead of posturing, Groupers will darken their colors to black as the approach, as if sending the same signal in a different language.
Just a few weeks ago I was astounded to see a Peacock Flounder displaying the most electric shade of turquoise on its spots that I had ever seen. I followed it for a few feet because I was absolutely mesmerized by the color. And right before my eyes the flounder sailed into a cleaning station and the Pederson Shrimp started crawling all over it. Now that was a pretty clear signal!
When we know what we are seeing underwater we can then understand what is supposed to be there – what species, what behaviors are normal.
When a sudden change happens we are the first to see it and recognize its value, from a rebound in the local grouper population to an invasive species showing up in our backyard. So pay more attention on your next dive – whether it is your 2059th dive or your 4th – and make a point to learn something. Find a fish you don’t know the name for and look it up, or stake out a cleaning station and watch all the different species that pay a visit. The more we learn, the more we ask questions, and the more we want to know.
Popularity: 1% [?]
