Lionfish

[00:00:00] Alex Re: Hello, welcome to On Wildlife. I'm your host Alex Re. On this podcast, we bring the wild to you. We take you on a journey into the life of a different animal every month, and I guarantee you, you're gonna come out of here knowing more about your favorite animal than you did before on today's episode.

[00:00:19] We'll be talking about a sea creature that's found in a lot of places where it's not supposed to be. They share part of their name with a beloved animal, but they don't get the same love. They've got huge spines and will eat almost anything. So join me as we swim around the coral reefs. To talk about lion fish.

[00:00:55] Lion fish are native to the South Pacific and Indian oceans. They prefer to live in warmer tropical waters, and they're usually found at depths of around 20 meters. They live among coral reefs and mangrove forests. They can only live in saltwater, and as some of you may already know, they're also abundant in areas that they're not native to.

[00:01:19] They've been found along the northeast coast of the United States all the way to South America. We're not exactly sure how they were introduced into the Atlantic Ocean. But some believe that they were released by people who had them as pets or by aquariums around the 1980s. And some genetic research indicates that every lionfish in the Atlantic Ocean descended from just 10 females.

[00:01:46] This has had major impacts on their non-native ecosystems, which we'll get into a little bit later. The two species that are known to be invasive in the Atlantic are the Red Lion fish and the common Lion fish. But in total, there are 12 recognized species and they all fall under the genus terras, which means feathered or winged.

[00:02:07] In Greek, it's easy to see why they were given this name. When you take a look at their physical characteristics, all lionfish have 18 spines on their body that kind of give the appearance of bird feathers. But when you're looking at these fish head on the spines kind of look like a lion's mane, which is why they have the name Lion Fish.

[00:02:29] Most lionfish species have brown or red stripes that run the length of their body and are on their spines as well. Red lionfish are one of the largest species they can grow to be just under 19 inches long, which is about as long as the height of four soda cans stacked on top of each other. Males are usually larger than females, and lionfish can live for about 15 to 20 years in the wild.

[00:02:56] Just like an actual Lion Lionfish are predators. They eat almost any animal that's small enough to fit into their mouth. They've been known to eat over 70 different species. They're even able to dislocate their jaws in order to take in larger prey. And they do have a lot of tiny teeth in their mouths, but these are mostly used for grabbing and holding on to prey rather than for chewing like our teeth.

[00:03:24] They'll eat fish, shrimp, crustaceans, and more. So their carnivorous studies have shown that one lion fish can eat over 450,000 fish in a year. They're mostly nocturnal hunters catching most of their prey at night, and they're described as ambush predators to catch their prey. They often lay still on the ocean floor until an unlucky animal comes along for them to quickly attack and they swallow their prey hole.

[00:03:55] Oh, they're also extremely fast and agile, thanks to a few characteristics such as a specialized swim bladder and cycloid scales. Cycloid scales are scales that are rounded and overlap each other. This allows for a lot of flexibility and agility, aside from ambushing. Another method that they use to catch their prey is to back it into a corner using their large fins.

[00:04:21] They're also able to blow out jets of water, which can disorient their prey in their natural habitats. Lionfish aren't necessarily the top predators. Some animals that eat them are sharks, groupers, and eels. They can use their agility to escape these predators, but they have a more powerful form of protection, and we'll talk about it right after the break.

[00:04:55] Today, I wanna give a shout out to Ellie and Bee from California. Ellie's favorite animal is a cheetah and bee's favorite animal is a wolf. Did you know that cheetahs use their tails as rudders to help them turn when they're chasing down their prey and wolves can hear each other's howls from 10 miles away.

[00:05:16] Remember, if you wanna shout out, send an email to on Wildlife dot podcast. At gmail.com and tell us your name, where you're from, and your favorite animal.

[00:05:34] Now let's get back to the episode. Let's talk about the main form of protection for lionfish. Remember those long spines that I was talking about earlier? They're actually venomous. The spines are covered by a sheath made of their skin, but when they're touched, the sheath is pushed down, which triggers their venom to be released.

[00:05:55] This venom isn't usually deadly to other animals, but it can cause a lot of pain for multiple days. If you're stung. And they can sting you even after they're dead. Don't worry, they won't go out of their way to sting you as long as you keep your distance from them. And one of the reasons why they may have stripes is to advertise to other animals that they're dangerous and not to go near them.

[00:06:19] This is similar to why poisoned dart frogs are really colorful. The science word for this is a antisemitism. Some studies even suggest that lionfish produce sounds with their spines, which could be another way to warn predators that they're dangerous. You wouldn't think that communicating with sound would be that effective underwater, but a lot of aquatic animals use sound as a form of communication.

[00:06:44] Scientists have found that lionfish are able to produce other low frequency sounds from the muscles in their swim bladder. They may even be able to change the length and size of their swim bladder in order to change the pitch of the sound that they're making. So sound may play a large role in helping lionfish survive in the wild.

[00:07:05] They also rely on their eyesight, sense of touch and chemical sensors in order to navigate through their environment. One other awesome thing about them is that they can change colors, and they do this for two main reasons. Reason one is to avoid predators. They use color change to blend into their environments.

[00:07:25] When they feel threatened, they can make themselves appear darker or lighter, depending on where in their environment they're hiding. Reason number two is for communication with other lionfish. They can let other individuals know if they're stressed or if they're trying to be aggressive. Most lionfish species are solitary until it's time to mate.

[00:07:48] Males will usually mate with multiple females and they'll actually use their spines in a courtship display in order to attract the females. Males have also been known to be more aggressive than females and are territorial towards other lionfish males. Female lionfish can produce 30,000 eggs each mating cycle.

[00:08:10] The average mating cycle lasts around four days, so she can produce around 2 million eggs per year. And in past episodes we talked about animals that do this, like the octopus or jellyfish. The majority of these eggs won't produce an individual that will make it to adulthood, which is why they make so many of them less than two days after they're fertilized, the eggs will hatch into larva, which will only be as small as a penny.

[00:08:39] After about 30 days of growing, they become juveniles and they reach adulthood when they're around a year old. This means that they reproduce really quickly. Now, it's important to talk about lionfish as invasive species because they're wreaking havoc on a lot of ecosystems that they've been introduced into.

[00:09:01] If you think about all the things that we've talked about so far, them being introduced into new habitats is a recipe for disaster. First of all, like I just said, they reproduce very often and very quickly. Also, they eat a large amount of fish and they aren't picky about what they eat. It's believed that in some ecosystems, lionfish have decreased their prey population by 90%.

[00:09:29] And lastly, they have really good defense mechanisms to avoid potential predators. In areas where they're invasive. None of the animals have evolved alongside the lionfish, which means that there are not a lot of animals that have them on the menu. There isn't a lot of great information about how many non-native lion fish are in our oceans right now.

[00:09:51] But a study done way back in 2015 estimated that in the Belize Barrier Reef, which is in Central America, there were close to 750,000 lion fish, which are invasive to the region. So imagine what it could be like 10 years later. An example of the harm that they've caused in their non-native ecosystems can be seen in The Bahamas between 2003 and 2009.

[00:10:18] During this time, they depleted the population of parrot fish, which eat algae in their juvenile stage. Because of this, there was an algal bloom. The algal bloom basically suffocated the coral reefs causing the coral reef coverage to decrease by 88% in some areas. Some organizations have been trying different strategies in order to reduce the lionfish populations in non-native areas.

[00:10:44] Let's take our last quick break and then we'll talk more about how some of these strategies work.

[00:11:01] Time for today's trivia question. What is the only bear species that's found in the Southern hemisphere?

[00:11:17] The answer is the Spectacle Bear. They live in South America and are known to be shy and reclusive.

[00:11:36] Now back to the episode, one of the most interesting strategies for decreasing invasive lionfish populations. Comes from Honduras where they're trying to train native sharks to eat the lionfish. When people catch lionfish, they feed them to the sharks to give them an appetite for them. And this has actually had some success as sharks in the area were seen eating lionfish.

[00:12:00] After the strategy was put in place, one company has created a robot that travels around the ocean where lionfish are invasive and zaps them. But this might not be the most humane thing. People have also been encouraged to start eating lionfish. They're safe to eat after the venomous spines have been removed.

[00:12:20] This can solve multiple problems at once because the more we rely on these invasive species for food, the less we need to rely on native species that will keep the ecosystems thriving. Plus, with the world's ever-growing human population, it's great to be able to introduce a sustainable food source. Not only that, but there are also lionfish derbies, which are competitions to remove as many lionfish as they can in one day.

[00:12:48] I. In the Florida Keys One Derby was able to remove over 1600 lionfish in a single day. It may not seem to be the most ethical thing, but this could potentially save countless amounts of native species. I also wanna point out that it's not the fault of the lionfish that they're invasive. They were introduced to non-native habitats by humans, and they have no idea that they're not supposed to be there.

[00:13:15] This is where the ethical dilemma comes in. Should lionfish have to pay for the mistakes that humans made? But we also need to think about protecting our native habitats. So it's really important not to think of lionfish as just an invasive species because they're important in their own ecosystems.

[00:13:34] They help to keep other populations in check and are a part of their native food web. Although their populations aren't currently decreasing, the habitats that they live in could definitely use our help. They're native to areas with huge amounts of biodiversity, like the Great Barrier Reef, which is suffering from a lot of human made problems.

[00:13:56] For example, because of climate change, the oceans are warming, which is causing the coral reefs to die off. And overfishing is depleting the food sources of lionfish and other animals. Not to mention our own food sources too. If we keep taking with not much to control us, soon enough there won't be anything left to eat and all of these habitats could be gone.

[00:14:18] I. We are kind of like lionfish when they're in their non-native habitats. We have no natural predators and kind of an insatiable appetite. The big difference is that we actually have a choice to change what we're doing for the better. So it's crucial that we support organizations that are protecting these ecosystems.

[00:14:38] You should go check out the Great Barrier Reef Foundation, Atlantic Marine Conservation Society, and the Coral Reef Alliance, who are making sure our oceans stay healthy so that animals can thrive in their natural habitats. I. Thank you so much for coming on this adventure with me as we explored the world of Lionfish.

[00:14:59] You can find the sources that we use for this podcast and links to organizations that we reference@onwildlife.org. You can also email us with any questions at On Wildlife dot podcast@gmail.com, and you can follow us on Instagram at On Wildlife. Or on TikTok at On Wildlife. And don't forget to tune in next month for another awesome episode, and that's on Wildlife

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