Lionfish Invasion: How a Voracious Predator Reshapes Ocean Ecosystems

[00:00:01][Music] [Music] da okay sure my [Music] come so we're here on a a a shipwreck uh diving site here off the coast of North Carolina and this is a site that we've been collecting a number of lion fish over the years these fish that we're bringing that the divers are bringing up today we're going to be using for research at our Laboratory [Music] for [Music] oh [Music] [Music] [Music] sh [Music] [Music] [Music] that massive that's a good haul that one big female here [Music] you got that down don't you yeah [Music] man we okay think [Music] fish about marking them in terms of uh knowing their genetic identity based and we might need to add new markers to so using the genetic tools and these molecular markers that we're seeing here these genetic polymorphisms one of the things that we're hoping to be able to tell is how many fish were originally introduced into the east coast of the United States so you know when you look at two fish and they look morphologically to be very similar you can't distinguish whether or not those fish came from the same parents or not and so using these genetic polymorphisms we can actually look at the amount of genetic diversity that's present in these invading populations and try to track back to see what's the minimum number of fish that were introduced into the United States initially genetics research shows that we have a a very few number of lion fish that were introduced into the Atlantic um probably fewer than 10 which was introduced into the United States likely from the aquarium trade it is a very popular aquarium species that is imported into the US from um Indonesia from the Philippines uh we know that many thousands of lion fish have been imported into the United States in the last decade [Music] the reason uh L fish were introduced is still not clear and we know that is a bad idea and there have there are many Outreach campaigns and efforts to try to inform the public about the impact acts of releasing your pets Into the Wild [Music] [Music] so there are many different aspects of lfish life history and their biology and ecology that have really allowed this um Invasion to progress um and for Lish to become one of the most aggressive Invaders on the planet [Applause] [Music] [Music] battle scar and Jason you don't have defa either no [Music] for [Music] [Music] [Music] I'm very worried about the future of marine ecosystems in the Bahamas because of the L Fish Invasion are we going to have reefs dominated by lots of lion fish with very few native species this can have impacts for commercial fisheries and recreational diving and of course just the Ecology of chy fish um where you're going to get dominance by one species [Music] oh for [Music] what ah here we have a fantastic strike of the lion fish lion fish are unique among fish predators in that they have incredibly protrusible Jaws uh they use suction to generate a suction pulse of water that draws the prey into the mouth the human eye sees at about 30 Hertz that means at about 0.33 milliseconds and you can see here by this time stamp that this behavior of striking at the prey is occurring in onethird of the time that the human eye can perceive and you'll see here that the jaw actually protrudes over 40% of almost 40% of its head length and when it m reaches his maximum jaw protrusion it expands its head from the side and it what basically like sucking through a strw it sucks in the [Music] [Music] prey when we think about kinematics of how the jaws and Fishes work you got to keep in mind that the skeleton of a fish or the skull of a fish rather the skull of a fish is actually made up of over 20 different bones so here we have a skeleton made by a colleague of mine Steve Husky and you can see how intricately aligned all the different bones are in the head of a lion fish [Music] now when we compare this lion fish to other predators that have been examined using this kind of kinematic analysis we see that it falls out about third place among all fishes in terms of the amount of jaw protrusion it can generate the uh all-time champion of course is a pulus insid known as the sling jaw Rass which is also common in the Red Sea um here we have a cichlid known as patin spendid it's a South American species that is in found in the freshwater Amazon region and then we have the lion fish among Marine fishes it's very very effective in terms of how U it can feed on its [Music] prey running the water and making it thin so like you can make a sheet of water in de gas the thinner you make the water the easier it is for that water to release the gas that's bound that's super saturated in it okay so this is a respirometer we have a a chamber with water passing um being pumped through the chamber and into a reservoir and we're measuring the dissolved oxygen content of the water as the water passes through the chamber as the lion fish is respiring and it's removing oxygen from the water as part of the respiration process and so if we're able to measure the water coming oxygen levels of the water coming into the chamber and the oxygen levels of the water exiting the chamber so we've learned that that lion fish uh can consume as high as 6% of their body weight per day uh over time at some of the higher temperatures and when calculating that feeding rate uh we've learned that it can have quite an impact on the fish Community um in some cases lion fish can remove um a considerable biomass of small forage fish fishes um and can even deplete that biomass causing change to the to the reef fish Community including biodiversity and forage base that we know is really important for commercially important species like Snapper and grouper this something right there it may or may not be on his fins and his body yeah yep [Music] [Music] [Music] pretty much it was a good dive but a lot of line fish considering we just removed uh fish from this reath 3 months ago okay okay so the Gap height and width yep Roger that Cape height we got 5 cm okay Cape width is 4 cm a crab oh crab yep see the yep okay so we had a clinging [Music] crab yep in level three and again that volume was that volume was two M tell what we have in there I can see right now lime fish have colonized virtually every Marine habitat in the Bahamas from shallow water call reefs to Deep Water call reefs to M Groves to Sea grass areas to marinas to sandy beaches around artificial structures this makes local control efforts very difficult because we have to Target not one or two um habitat types but multiple habitat types over an entire [Music] [Music] archipelago for [Music] [Laughter] is [Music] [Music] give you a hint where do they live Coral beefs mangr near beaches warm areas everywhere yeah we have them everywhere in all sorts of habitats all on the the dorsal side here and how many dorsal spines do you think that lion fish has anybody know so there are 13 spines on the dorsal fin of uh these species of lion fish okay remember how Nicolas said there are many different species of lion fish but the one that we find here in the Bahamas has 13 dorsal spines and these are each independent they can move around and as you can see this skin right slides down very easily away from the spine okay so this means that I the tissue the venomous tissue is actually contained within this all right so if I touch it it's okay if I poke myself and Venom myself then that's where the problem is so even if this even though this fish has been dead for a few days even though um the spine is removed it still possibly contains Venom that can harm me so the the Venom glands when they are disrupted they release Venom into the victim and the Venom is a a neurological toxin that affects the nervous system it can cause extreme pain um in humans allowing for things to occur like paral is temporary paralysis um blistering extensive swelling um and and very extreme pain for for several hours it may be similar to a wasp sting an extreme wasp sting at first that will gradually get worse um there have been some cases some very rare cases in which people have died from lion fish and scorpion fish stings we're not aware of any in the US currently this is the spine itself here you can see the hard bony structure with the tip this is the spine these are the grooves of the spine here and then this is the Venom gland [Music] [Music] [Applause] [Music] in the Red Sea we see that the lion fish is in balance with the natural ecosystem the lion fish is a native predator of the Red Sea but it also has competitors uh what we see in the Red Sea is we see lots of grouper species that are about the same size and are also very effective Predators so when we see lots of groupers we see very few lion fishes and vice versa [Music] in the ocean of the southeast and tropical Caribbean Sea um there are really no natural predators that have been documented to actually be praying upon lion fish at a rate that can control their local densities [Music] [Applause] [Music] [Music] for um lion fish have a very robust and uh vigorous reproductive biology they are capable of reproducing every 3 to four days they the females can release over 2 million eggs per year uh then they can become sexually mature within a year so the first 6 months of data looks really exciting we found that if you remove lme fish once every 3 months or once every 6 months from coral reefs we are able to reduce lme fish numbers by 50% or more than if we done absolutely nothing at all what's even more exciting is the fact that removing lme fish only once every 6 months seems to have the same ecological impact as removing lion fish once every 3 months in terms of we're having the same number of lion fish uh densities at 3 versus 6 month removals this is exciting because this means that in terms of management we can get the same ecological effect for half the amount of effort so this looks really hopeful because it looks as if we will be able to control lime fish in small localized areas with not a lot of effort [Music] [Applause] [Music] no don't don't all right all right the heemans NES get uh into eating them some of Na get eating them and um before before when it came first um everybody thought that the meat was pricing because they understood that the lion fish had a poison Venom but people are now growing out of that fear and beginning to eat them eat the meat [Music] [Music] wait till you start suiting up in okay clear for [Music] [Music] [Music] [Music] [Music] there you we going to sit you right here [Music] still ling fish down there oh they're not going to go away hey Cecilia how you doing man y just come back off a tripic yes all right all right how it been all right all right it went well youall caught a lot of fish caught some all right you didn't happen to see any lion fishing um yeah on this trip yeah all right all right A lot of them all right yeah we saw plenty of them all right cuz you know there's there's a big problem since there's invasive species yeah what they doing they killing out all the fish yeah in 2009 we decided to do something about it we developed the national lion fish response plan the plan serves to maintain a marine ecosystem as well as to control lion fish populations and amend Fisheries regulations uh the lion fish problem is such a huge problem that one study actually shows that it has reduced prey species down to about 65% so what are we going to do about it we're going to eat them to beat them my but when you do have it on your menu a lot of people are so excited to have it because they can't really have it any other place so all in all it's a win-win situation you save the environment and you have a good um tasting product on your menu [Music] out [Music] that's what I'm talking [Music] about some 50 L Fish I didn't even got them I just so you got there and the wood steps sit back hands to the side down to the center [Music] [Music] [Music] [Music] you you should try to get this I think he might get a fish here H he might get a fish here he's pinned them all up against the side yeah oh there's a big one by that Corel oh yeah there it is they like it's hunting there's all the little juvenile fish there huh yeah going to get one that's a big one sees the one at once look at it that's a good size fish this one seems more to be just tunning not even minding us being here yeah and there's a big specimen nice lion fish here it's all on its own you might notice there's not really any fish around it and it looks pretty swollen stomach so pretty much eats everything around it and then moves to another spot so car yes on a normal sub dive yeah when you're kind of cing down to 1,000 ft how many lion fish do you think you see on a th000 foot dive maybe 10 but you see them I've seen them as deep as 800 ft but mostly you see them you see the most between two 2 and 400 ft okay so they even go down to 800 ft but most of them around 2 300 ft 2 to 400 so finding one here at 500 ft isn't abnormal but they're mostly abundant higher up yeah they're if we drive along at 300 ft we'll see just constantly are we heading up or what I'm going to got to look at it by the squirrel [Music] [Music] [Music] [Music] [Music] [Music] Shark Feeding has been controversial for a long time and also obviously Shark Feeding with lion fish because it can change the um behavior of the sharks in their natural um environment now yes it is true that it does everything that we do on the water it will affect their behavior um introducing the lion fish to the Sharks which is an new organism that they never seen before especially in the Caribbean has helped because we only did a couple of times probably two or 3 months of it and then after that we haven't even fed the sharks with them and it seems that they have recognized the lon fish as a food source without us feeding them to them so yes it does has an effect with sharks but I think in a you know in a bigger picture we have helped the reef and we hope we help it for a future permanent [Music] future I would say that I am not optimistic about the um future of lion fish I see the lion fish Invasion progressing uh continuing to expand in both its distribution we now have lion fish in the Southeastern Caribbean we will likely see them continue to invade along the uh coast of South America perhaps as far south as the northern coast of Argentina lime fish do not survive when the me winter bottom water temperatures go below 15° C so this 15° Mark appears to be a threshold where above that lion fish survive and thrive but below that you just don't even really find them at all but they likely distribution is is probably going to extend all the way from from Cape hatas North Carolina in the north All the Way South to the northern coast of Argentina or we're not thinking that it's likely that lion fish will disperse through the panwa canal probably for a couple of reasons the water's kind of cold in the Pacific so there's a big temperature difference between the Pacific and the Atlantic as well as there being freshwater lakes that could be also be a barrier to dispersal however we really don't know for sure whether they can um disperse through the Panama Canal [Music]