foreign not so long ago a record-breaking goldfish was caught in Champaign France an angler reeled in a 67-pound specimen from Blue Water Lakes the giant goldfish was released back into the wild 20 years ago and has since become one of the largest known specimens in the world it took the angler 25 minutes to reel the fish in after that he took some photos and released it back into its natural habitat well it wasn't exactly natural in our mind goldfish are Miniature creatures but their size depends on the environment they live in why grow big if
you live in an aquarium and eat scarce food a real body of water with lots of hearty food is a different story with conditions like that the fish will easily turn gigantic don't forget about the genetics of these fish they're incredibly tough creatures that can handle low temperatures and eat anything but removing your goldfish from the fish tanks hoping they'll be happier in the wild is a very bad idea or rather the fish might feel better but the life of all the other creatures in the pond will be at risk giant goldfish are a threat
to wildlife in some areas of the United States these large fish have features that make them especially dangerous and their activity can lead to devastating effects on aquatic ecosystems yes this is going to sound a little weird but goldfish are bold even impudent creatures they'll explore new areas of rivers and ponds eating anything they find along the way seriously goldfish are incredibly voracious they eat snails small insects fish eggs and fry that actually serve as food for Native species as a result native species are starving and may go extinct aside from threatening native fish goldfish
also inhibit algae growth by stirring Up Mud during feeding and increasing water cloudiness as a result less sunlight penetrates beneath the surface which affects the growth of aquatic plants which in turn produce oxygen and act as shelter well goldfish are also a health risk they carry parasites passing them to other fish and spreading them across bodies of water overall goldfish cause a lot of problems and things only get worse when humans start feeling like setting their pets free we also Finding Nemo and remember how the characters wanted to escape to the ocean but as is
often the case real life is not like the movies if you catch a fish in water and then release it back it's one thing but introducing new species into a different habitat can have disastrous consequences because these new species are quite capable of becoming invasive then they'll become a threat to local wildlife in the ecosystem as a whole the Exotic Animal trade is one of the main causes of biodiversity damage worldwide indeed many animal species in the United States are listed as endangered or threatened exactly because of invasive species one example of an invasive species
is the tigu lizards which have become so widespread in Florida that they now regularly raid the nests of endangered species such as the gopher tortoise and these tortoises are crucial because their Burrows are home to hundreds of other animals another example is the Burmese python these snakes became an invasive species in Florida around 2000 and it's these pythons that have been blamed for the decline in mammal diversity and then there's the red lionfish which is introduced into Florida waters in the late 1980s the red lionfish is an aggressive Predator that had a major impact on
Coral Reef ecosystems greatly reducing the numbers and diversity of their inhabitants well you probably already realize how exactly it works invasive exotic species can introduce diseases into the wild these diseases can quickly spread to native animals causing mass extinctions and threatening entire populations simply because the disease is a new one which means the animals can't cope with it the activity of non-native Predators can also affect the balance of the food chain in short there's nothing good about that at all some invasive species are so successful they can spread across the planet this is what happened
to the red-eared sliders these animals were popular as pets however when their owners realized these Turtles required large aquariums and expensive filtration systems and that they could live up to 50 years they began dumping them outside this caused a real explosion in Turtle population currently populations of feral red-eared sliders exist in Israel Guam Australia and the Caribbean islands yes that's how widespread they are in Japan red-eared sliders outnumber the native turtle species eight to one in a single region of the country they consume up to 320 tons of water weeds each week their larger body
size and in the wild the red-eared sliders can grow to 12 inches long and high breeding rate allow them to quickly dominate native species in literally every regard however it's not just about dominance red-eared sliders can also cause harmful algal blooms that can damage the environment or expose people to salmonella which they commonly carry for this reason red-eared sliders rank 98th on the list of the world's 100 worst invasive species in 2021 and moved up to 93rd position by 2023 and something about this trend doesn't sit well with me but what makes red-eared sliders so
successful besides size and breeding rate there are some pretty significant factors first of all these turtles have an amazing ability to survive in a difficult environment they can live for months without food slowing their metabolism down when resources are scarce and when food is prevalent red-eared sliders aren't too fussy and will eat pretty much anything they come across fish insects vegetation and even human snacks like potato chips they're sturdy carapaces and high speed in the water also provide reliable defenses from predators like raccoons and coyotes these features make red-eared sliders very tough creatures that can
easily adapt to any environment no matter how hostile or unpredictable it may be red-eared sliders could even be found in Morningside pond in Midtown Manhattan not far from the famous Central Park and there are actually a lot of them there and you won't even see most of them because they're hidden underwater however we know that almost all of these Turtles were once pets people no longer wanted or couldn't care for many of these released animals are now overweight as evidenced by their unusually thick legs and necks well when there's food and no Predators around even
a turtle can get chubby this Pond used to be home to eight other turtle species but competition with red-eared sliders for food and a place to get warm in the sun has significantly reduced the local population well our next animals believe it or not are dogs this may sound very weird it would seem you would never take dogs for an invasive species that takes over habitats and ruins biodiversity but first things first a couple of years ago biologist Gallo zapaterios placed camera traps over 772 square miles across the Andes intending to film hognose skunks Mountain
Cody's and other wild animals but in the end all he saw on his cameras were dogs there were so many pictures of dogs that eventually the biologists decided to change the topic of his research this is really important because domestic dogs have become a serious threat to Wildlife not just in the Andes but all over the world dogs rank third after cats and rodents as the most dangerous invasive Predators among mammals actually it's pretty clear how dogs end up in the wild humans clearly had something to do with that turns out that the increase in
domestic dog population has become a serious threat to Wildlife around the world approximately 200 animal species are threatened by the growing dog population as the number of pharaoh and free-ranging dogs keeps Rising conservationists are concerned that things will get way worse dogs affect wildlife in five main ways first and foremost it's interbreeding with closely related species this can't be avoided no matter how different dogs are from say coyotes researchers in Europe fear that dogs are interbreeding with wolves and if things go on as they do wolf jeans will lose their purity second the threat comes
from competition with wild animals for prey dogs need something to eat too then comes transmission of dog diseases to wild animals disruption of the ecosystem and finally predation the typically omnivorous diet of dogs means they have a strong potential to affect the diversity of species a New Caledonia for example dogs have killed at least 19 endangered kagu in just 14 weeks that's very fast humans have domesticated dogs and over 15 000 years of our relationship dogs have become so accustomed to us they can understand us without words and even stray dogs that have never lived
with humans are still able to recognize and correctly interpret human gestures in one experiment a group of untrained dogs was offered two closed Bowls one with raw chicken and the other was empty with just the scent of food the experimenter standing next to the dogs pointed a finger at one of the bowls in most cases the dogs approach the bowl to which the experimenter pointed indicating that they understood his gesture and they understood it without any training this ability has probably become innate over Millennia and even traumatic experience with humans has not influenced it in
any way and stray dogs definitely have some bad experience with humans what if I told you that cats can also undermine biodiversity and be an invasive species that's right cats Steve can you imagine that say my name cat you're goddamn right cats are the ultimate killing machines they're agile and stealthy enough to get close to their prey they also have sharp claws and teeth that help them quickly Massacre their prey they may be cute fluffy and Goofy but we shouldn't forget about their dark side if we want to protect wildlife of course the area around
the town of Waldorf in Germany is home to the crested Lark it's an endangered species so the authorities ordered the owners to lock their cats indoors over the summer otherwise they face a significant find the figures look impressive indeed 500 euros if the cat is caught outside and 50 000 Euros if it kills a poor Lark that's just trying to go about its business this policy makes it clear how serious an issue cats can be according to statistics cats can kill billions of birds and mammals each year in the United States in the United Kingdom
cats kill 160 to 270 million animals each year a quarter of them Birds although the figure may be higher because of the evergrown population of domestic cats in addition researchers have estimated that cats can have four to ten times the impact on Wildlife as wild Predators all thanks to their hunting skills this fact secured cat's 38th Place on the list of world's worst invasive alien species to be honest it's very weird to realize that this horrible invasive species is now peacefully sleeping on my sofa and all of this points to a pretty obvious conclusion cats
could be the cause of Extinction of some species I admit this may come off as an unexpected thought however the thing is cats are among the main reasons for the extinction of certain species of birds and other animals the most famous example is lyelles ran a small flightless bird that once lived on Stevens Island in New Zealand when Europeans arrived on the island in the late 1800s they brought cats with them and the Lyles ran apparently disappeared within a year it just wasn't ready for Predators like these cats have been known to be the reason
for The Disappearance of a wide variety of animals such as amphibians reptiles and mammals many birds were wiped out by them including parrots and Shorebirds in some areas where cats have been introduced into the ecosystem they've caused so much Devastation that entire habitats have been destroyed fortunately there are ways to solve this issue before it's too late for some species of animals and plants one way is to keep cats indoors when they're not under the supervision of their owners this will keep pets from preying on wildlife and protect them from being run over by cars
or attacked by other wild Predators such as coyotes or foxes well if you do have to let your cats Outdoors experts advise imposing a curfew that is taking your cats for walks at a time when there's a minimal chance of encountering wild animals for those who think the curfew sounds too cruel there's another solution a birds be safe feline collar cover I'm not promoting anything it's just this thing looks really funny the cover is very bright which means it's much easier for birds to spot the cat they'll be able to fly away faster than the
domesticated Predator will pounce at them covers come in different sizes and colors to fit different cat breeds they're made of lightweight materials so they won't bother your pet except that they might offend its sense of style the effectiveness of the birds be safe collar cover has been proven in several scientific studies conducted in different countries in 2015 a field study conducted in the U.S showed an 87 percent reduction in the number of birds caught by cats wearing brightly colored collars compared to cats without collars subsequent studies in Europe and North America showed more than a
60 percent reduction all right so we found out dogs and cats can be invasive species or even Turtles who's next on our list goats I'm not kidding domestic goats are looking down at cats and Turtles from the 17th Place on the list of the world's worst invasive alien species normally domestic goats are bred for meat milk and wool however due to human negligence these animals can become pests in many areas it doesn't really matter whether goats run away on their own or are deliberately released into the wild they adapt quickly to their new environment anyway
there are so many feral goats in Australia people talk about the goat plague and not just because goats like any other invasive species can spread diseases goats first arrived in Australia in 1788 but some of them escaped soon well or they were released on purpose whatever the case the goats didn't die but became Pharaoh when multiplied actually they aren't too different from domestic goats except that they have bigger horns nowadays at least 2.6 million feral goats are found in 28 percent of Australia and there's nothing good about that feral goats can become real pests because
they're appetite and grazing habits inflict severe damage on the vegetation and upset the balance of plant species feral goats have been known to completely strip the leaves and bark from shrubs leaving valuable grazing plant species unable to recover this leads to the permanent replacement of these plants by annual and less valuable perennial species over grazing by Pharaoh goats can also lead to widespread soil erosion goat sharp Hooves expose the soil to further erosion by wind and rain which could result in landslides also goats compete with local animals and livestock for shelter water and food sources
which results in shrinking resources for other species moreover feral goats can serve as a reservoir for infections such as foot and mouth disease rabies and cattle plague which I've already mentioned diseases can spread rapidly among domestic animals as well as among humans in Australia alone feral goats are responsible for the loss of 25 million dollars per year yes we're only talking about Australia but there are goats in other countries as well and they misbehave there too the lockdown of 2020 had many unexpected consequences one of which was the Bold behavior of goats and landidno in
the United Kingdom while the city remained deserted due to coveted restrictions goats took the opportunity to explore the empty streets they were spotted in parking lots obstructing the passage of cars chewing on Hedges and running through the streets at night the goats even slept at bus stops and fought each other during the day over public places their behavior became so disturbing that City officials even set up a task force to control the goats and keep them away from people unfortunately the task force failed to sort out some issues due to the restrictions during this period
vets didn't give the goats contraception injections as usual and that led to a baby boom among goats all over the town now imagine the following scene a field about 70 Acres large all covered with craters like after a meteor shower The Roots below a huge oak tree have been dug out and exposed the grass is trampled not even a tractor could drive through this terrain but what happened here it's the Wild Hogs Wild Hogs are common in many parts of the world but it hasn't always been this way Hogs Wilder otherwise are not native to
the United States Christopher Columbus introduced them to the Caribbean and then another Navigator Hernando de Soto brought them to a place which is now known as Florida the early settlers of Texas allowed pigs to roam freely until needed and that let's just say it led to certain consequences during Wars or economic downturns many settlers abandoned their farms and the pigs weren't left to fend for themselves in the 1930s Eurasian wild boars were brought into Texas and released for hunting they bred with free-ranging pets and escapees that had adapted to the wild but that was only
the beginning Hunters were almost never after wild boars considering them challenging prey game ranchers set out feed to attract deer but wild boars pilferred it becoming more widespread finally improvements in animal husbandry reduced disease among domestic pigs as well as in Wild fours let's not forget that wild boars are very intelligent mammals they avoid any attempt to be caught or killed and if any of them do encounter Hunters these animals get even smarter in addition wild boars have no natural Predators which means a population can be maintained without any interference sows start breeding early and
do so quickly so even the population that's been reduced by 70 percent returns to full strength within two to three years wild boars eat almost everything they destroy entire fields and sometimes eat livestock especially Lambs goats and calves boars can also eat wild animals such as deer and quail and eat sea turtle eggs this makes wild boars an incredibly dangerous invasive species they can cause serious damage to both ecosystems and the economy not even the soil is safe from them wild boar populations eroded pollute streams and other water sources which can lead to fish dying
these animals are also potential disease carriers because of their susceptibility to parasites and infections that can be transmitted to humans through contact with contaminated water or food sources and even in cities you can't escape wild boars if they suddenly want to pay you a visit wild boars ruin golf courses athletic fields Gardens and even kill pets by the way they rank 91st on the list of the world's worst invasive alien species they aren't as bad as goats but I still have something to surprise you with and that is chickens wild chickens in Hawaii have taken
over downtown Honolulu and residents are seeing these birds everywhere I mean literally everywhere feral chickens crow it any time of the day and night but this is just the tip of the iceberg these birds damage crops spread weeds threaten native plants pose a road hazard and can be quite aggressive often chasing people they also disrupt businesses by leaving stinky droppings near restaurants and bothering customers with their loud crowing there's only one question where the hell did these feral chickens come from and in such numbers according to researchers several factors led to such a proliferation of
birds first the 1992 hurricanes that destroyed chicken coops and fences allowed the birds to escape and breed uncontrollably ever since second a 2015 study traced the Genome of feral chickens living in Hawaii today to the DNA from a chicken introduced to Hawaii by ancient Polynesians centuries ago third perhaps the chicken problem is actually caused by people who release domesticated Birds into the wild for entertainment and of course tourists play their part it's believed that they feed the wild chickens garbage and cat food which encourages the birds to stay close to people all the time fighting
feral Hawaiian chickens is hard because they can be quite fast when they need to take off and they fly to places that would be very difficult for humans to reach well you're not going to climb a power line to get a chicken although chickens sitting on power lines is quite a sight to behold it's typically a pigeon spot by the way pigeons can serve as a great example of how careful people should be with their pets to see what I mean let's look at history there are more than 400 million pigeons around the world most
of them living in cities but it hasn't always been that way the city pigeons that we know today actually descended from a wild ancestor called The Rock Dove about ten thousand years ago people started to tame and breed these birds for food but over time they realized that rock doves could be used for other purposes so these birds became Messengers that carried letters and navigational assistants helping Sailors then they evolved into decorative pets but all this had a side effect the birds flew away and began to breed freely in the cities and not just freely
but at a mind-blowing rate so it's people's fault that pigeons live all over the world today we've also created a favorable environment for them and if there was something pigeons didn't like they simply adapted to it there's a reason that pigeons are called rats with wings these days there really are a lot of them and they also carry diseases including ornithosis salinosis tularemia also pigeons can carry on themselves certain parasites such as fleas by the way it was fleas living on rats that once caused a plague epidemic in Europe pigeons of course are not known
to cause anything like that but still I'd recommend avoiding contact with them okay let's talk about something nicer than rats pigeons and plague-carrying fleas for example horses no I'm not going to tell you they're invasive species but the thing is in nature there are no Wild Horses I mean not at all not a single one mankind got too carried away with their domestication for years shawaski's horse was thought to be the only remaining species of wild horse on our planet but a new study conducted by scientists from the universities of Cambridge Durham and Edinburgh show
that this is actually not true jawski's horse's family tree was analyzed to determine its ancestry the results showed that it didn't descend from actual feral horses as previously thought but rather from domesticated horses that later returned to the wild you get it right there are no wild horses in the biological sense at least not these days the research team believes that about 5 500 years ago humans first began to domesticate horses for food and transportation over time some of these animals escaped captivity and turned into feral herds that eventually became what we now call shawalski's
horse but they're not wild from an evolutionary point of view such horses are like feral dogs the ones that still understand human gestures I hope horses won't be offended by this comparison it explains why you can't just let a domestic course go and consider it wild from now on moreover even the grandchildren and great-grandchildren of this horse won't be considered Wild this is what biologists claim but that's only if the horse can produce Offspring in the first place I've already said it in other videos and I'll say it again even wild animals whose ancestors were
all wild can't be released into the wild if they were raised next to humans this isn't about invasive species or taking over someone else's habitat in most cases these animals don't have the necessary skills and knowledge to survive releasing such a creature back into the wild will most likely get it killed due to competition and even if it adapts it won't be afraid of humans and it will die because of some hunter or scared tourist when an animal raised in captivity gets too close to him okay let's say the animals learned how to get food
hide and stay away from people but there's another important factor breeding animals have to leave Offspring it's their main goal in life and when you've spent your whole conscious life around people and have no idea how to hit on girls of your species well your chances don't look great but that's another story for another time see you later