Nature is anything but predictable. She constantly surprises us with new discoveries, strange anomalies, and baffling enigmas. We strive to understand her, but just when we think we have her figured out, we are presented with yet another mystery.

One such mystery can be found in the many cases of animals that turn up in places they have no business being in. It is not always completely clear how these animals have become so unexpectedly dislocated from their natural habitats, but one thing that is certain is that these cases are almost always perplexing.

Among the many reports of out of place land animals, one can find others that describe aquatic creatures, some quite large and dangerous, showing up in the strangest of places. The prospect of coming across a creature totally unexpected in the depths of a lake or river holds a certain peculiar fascination. In such locales we think we can fish and have an idea of what we’ll catch, that we can swim and be totally safe. We seem to have a sort of false sense of familiarity with such places, so when something totally new rises up from the water, we are truly reminded of how unpredictable nature can be.

Let us take a look at some of these head scratching cases of aquatic beasts that, for whatever reason, have wound up in some of the most bizarre places.

To most people, sharks are shadowy creatures that lurk within the depths of the ocean. These often frightening denizens of the deep are what we might expect to find along coasts, out at sea, or perhaps in our nightmares, but certainly not at a golf course. Right?

Welcome to the Carbrook Golf Club, in Brisbane, Australia, a place that gives the term “water hazard” a whole new dimension. The course boasts beautiful scenery, a full 18 holes of golf, and a lake full of sharks. The small lake, which is located in the center of the golf course, harbors at least six full grown bull sharks measuring from 8 to 10 feet long, whose dark shapes and fins slicing the surface of the water have become a common sight.

The sharks are believed to have become stranded in the small lake during flooding in 1996, when the Logan and Albert rivers broke their banks and spilled onto the course. Since then, the sharks have not only survived in their new habitat, but are thriving and are even said to be breeding, giving the lake its new name “Shark Lake.” Many golfers sit by the side of the lake watching the beasts swim through the water just feet away, and golfers often pause during games in hopes of catching a glimpse of the sharks before continuing on to the next tee.

Bull sharks are large sharks that prefer shallow water and are known to be generally aggressive. A great many shark attacks have been attributed to this species. They are perhaps most well known for their unique and somewhat disconcerting ability to survive in fresh water. In fact, bull sharks can thrive in freshwater habitats, and have been known to venture hundreds of miles up rivers. Bull sharks are often found in many rivers throughout the world, and have been seen as far up the Mississippi as Illinois. They are even known to pop up in lakes, such as Lake Nicaragua, a large freshwater lake in Nicaragua that is known to have a breeding population of bull sharks.

However, Carbrook Golf Club is thought to be the world’s first shark infested golf course, and as such has attracted considerable publicity with its unusual guests. The sharks have become popular for corporate events, and some people have wedding ceremonies at the lakeside, where fins can sometimes be seen cruising through the water in the background as the couples exchange vows. There is also a tournament held at the course called the “Shark Lake Challenge.”

The sharks might be frightening, but so far people have had mostly a positive attitude towards them. Some even go as far as to throw pieces of meat to the sharks, even though the lake is well stocked with fish. Whether people want the sharks there or not, when visiting Carbrook Golf Club, it may be a good idea not to dive in for a lost ball.

While the presence of bull sharks in lakes or rivers may be alarming, at least they are known to frequent fresh water. What of even larger sharks with no such propensity?

Although rarer, there have been a fair number of accounts of great white sharks lurking in fresh water. Perhaps the most infamous and deadly account is the Matawan Creek incident of July 15, 1916.

The incident occurred at the height of a series of gruesome shark attacks along the New Jersey shoreline from July 1 to July 12, 1916. In total, 5 people were viciously attacked by what is believed by many to have been possibly a great white shark. What is curious about this case is that during this string of horrifying attacks, three separate attacks also happened in a small freshwater creek 15 miles from the ocean.

Matawan Creek lies in New Jersey and is a partial tidal inlet of Raritan Bay. On July 15, 1916, 12-year-old Lester Stillwell was killed while swimming in the creek. During the grisly attack, 24-year old Watson “Stanley” Fisher jumped in in an attempt to rescue the boy, whereupon the shark turned its attention on the would be rescuer and killed him as well before disappearing into the bloodied murk. Later that same day, a shark ferociously attacked and severely injured 14-year-old Joseph Dunn in the very same creek.

The attacks in a calm freshwater creek so far from the ocean stunned people and created widespread panic. The attacks are so notorious that they are believed to be one of the inspirations for the novel and subsequent film “Jaws.” While the true culprit of these attacks remains unknown, some believe it to have been the work of a great white shark. That a large great white was captured in Raritan Bay two days after the attacks suddenly ceased seems to somewhat support this theory.

There is the chance that these attacks may have indeed been carried out by the more freshwater inclined bull sharks, but still other accounts in freshwater clearly describe a great white.

A fisherman at Tuggerah Lake, a small freshwater lagoon about 90km north of Sydney which is connected to the ocean by a small tidal channel, claimed to have captured a large great white shark in his net. The man described the shark as being bigger than his 18 foot long boat, and claimed it was around 21 feet in length.

The startled fisherman said he cut the net in a panic and watched the shark sink back into the depths of the lake. Tuggerah Lake had never had any reports of sharks in its waters before, and the find was said to be so incredibly odd that some experts have doubted the veracity of the story.

Another great white shark measuring 16 feet and weighing 3500 pounds was haunting marshlands and shallow, brackish water bordering on freshwater deep within St. Helena Sound in South Carolina in 2013. The tagged shark made its way much further inland than any previously observed great white and experts said it was highly unusual behavior for this species.

Great whites are not known to inhabit such habitats, nor are they known to have any tolerance for or ability to adapt to freshwater, yet there various other reports and sightings of great whites spooking people in freshwater lakes, rivers, and estuaries. There have even been sporadic and unconfirmed sightings of the beasts in America’s own Great Lakes.

If there were great whites in the Great Lakes, they would certainly not be the only toothy out of place resident there. The Great Lakes have produced quite a few accounts of pirahnas in their waters as well. The deadly piranha, popularized in Hollywood for swarming upon animals to strip them to the bone in seconds, are world renowned for their razor-sharp teeth and vicious bites. They are also native to the Amazon River Basin in South America, which makes the Great Lakes pretty far from home.

One piranha was caught at a popular swimming hole called Sandy Bottom, in Dollar Bay, Michigan, which lies along the shores of Lake Superior. The man who caught the piranha wasn’t quite sure what he had reeled in at first, and brought it to a bait shop where it was identified as a red-bellied piranha. Perhaps unsurprisingly, the unusual catch stirred up quite a bit of panic among swimmers in the area, with many people refusing to go into the water.

Experts asserted that this was an isolated incident and an individual fish, whereas piranha attacks usually are carried out by schools of them. Nevertheless, people weren’t rushing back to the beach.

In another case, fisherman Bill Locket was jigging for perch in a place called “warmwater bay” at the Monroe Power Plant at Monroe, Mich when he hooked into an exotic fish with a mouth full of sharp teeth. The fish, which measured 15 inches and weighed 1.79 pounds, was later identified as a red bellied piranha.

Another fisherman, a mister Toby Davison, was fishing for bluegill when he pulled a huge 18-inch, 4.5 pound piranha out of Lake St. Clair, which is part of the Great Lakes system and connects Lake Huron with Lake Eerie.

Piranha have turned up in all of the Great Lakes, and are thought to be the result of aquarium owners dumping exotic pets when they get too big to care for properly. It is not thought that the tropical piranha would be able to survive the cold weather of winters in the Great Lakes region, but they could possibly survive near the warm water discharge from power plants.

Either people keep releasing them or they are somehow surviving by huddling near the warm water of power plants, because whether the piranha can survive the cold or not, the somewhat sobering fact remains that they are sporadically reported in the region year after year.

If it seems odd for piranha to be caught in the Great lakes, there is also the peculiar case of a red bellied piranha caught in England. The 1lb, 4 oz fish was pulled in by angler Derek Plum, 46, at a small pond in Radnor Park in Folkestone, Kent. It was an extraordinary find, as reports of such tropical fish, so far from home in the wild in Britain are practically unheard of.

When fishing in England, as bizarre a catch as it may seem, piranha are still not the strangest thing that has been caught in British waterways. That distinction would probably have to go to the 196 pound swordfish caught by fisherman Brian Hynd in a Scottish river where no swordfish should ever have been found.

Hynd was out for a day of fishing with his nephew on the River Forth when he made the amazing catch far up river, 20 miles from sea. Swordfish are typically found in tropical and temperate waters. They are not known to venture as far north as Scotland and are never seen in rivers, which made the surprise catch quite a mind-boggling experience. Nothing of the sort had ever been seen in the River Forth before.

Yet the story gets even stranger. The swordfish, nowhere near its natural habitat, was not even caught on a hook and line. Hynd is a lobster fisherman. He had not really expected to catch any lobster in the river, as it was freshwater and lobster aren’t found that far inland, yet nevertheless he had set the pots out as sort of an experiment after hearing wild rumors of lobster being caught fairly far upriver.

Hynd was out collecting the lobster pots, which were totally empty as expected, when he found the swordfish thrashing about in the water, tangled in the lines of one of the pots. He described catching such a large swordfish so far up river as the shock of his life. Experts were also very surprised at the find.

There are a variety of reasons for why aquatic out of place animals might end up in such odd places. Sometimes it is due to climate change, which disperses populations outside of their historic ranges. Other times it is released or escaped pets, or animals introduced by humans in other ways, either intentionally or not. Maybe it is the result of a shortage of resources in their usual habitat which causes them to venture out in search of food, or a disaster of some sort uprooting an animal and whisking it away far from its home. Maybe the animal is just plain lost.

Whatever the reasons may be, one thing is for certain. When you are at your favorite swimming or fishing hole, or even enjoying a game of golf, and you come across a creature you never expected to see there in this place you thought you knew so well, it is easy to gain an appreciation for just how weird and unpredictable nature can be.