Check out this spider! Thank God they're small! See other arachnids from Costa Rica.
Sharks have always been a fascination for beachgoers. From the movie Jaws to Shark Week on the Discovery Channel, people who have never even swam in the ocean have fears and enthrallment with these creatures of the sea. The aura of sharks and their behaviors is what make these creatures so incredible to humans. Sharks will be in the waters that we research in Florida and the Bahamas and it is important to understand the species of sharks in these waters, why this region has shark attacks, the myths about shark attacks and lastly how to prevent a shark attack.
There are many different types and sizes of sharks common in the waters off the coasts of Florida and the Bahamas. The most common shark in the area is the Blacktip shark, which can grow up to eight feet long. It got its name and is easily distinguishable because it has a black tip on most of all its fins except for the anal fin (http://edis.ifas.ufl.edu/BODY_SG062). They often times come along shoreline in groups while hunting their prey of choice, the Spanish mackerel. Since there are so many Blacktips off the coastline of Florida they are also popular in the commercial fishing industry due to its abundance and its marketable meat. Blacktips are also responsible for the majority of “hit and run” attacks that happen to swimmers in the region (http://edis.ifas.ufl.edu/BODY_SG062). The next most common shark is the Spinner shark which is commonly mistaken for a Blacktip shark, but the Spinner has a black tip on all fins including the anal fin. The Spinner shark is extremely fast swimmer and can grow up to six feet long. Another common shark is the Sandbar or Brown shark. They mostly grow to be six feet but can grow to eight feet and are normally found in waters that are 60 – 200 feet deep. They migrate to the Florida coast during the winter months in groups but some stay throughout the year, “where they feed on the bottom fish, such as shell fish (http://edis.ifas.ufl.edu/BODY_SG062)”. The Blacknose shark is a small shark growing to a maximum length of five feet. They are found in the bay, lagoon and coral regions of Florida and the Bahamas. They got their name because they have a black smudge on the ends of their snouts. The Blacknose feeds on small fish but is also a prey for larger sharks. It also shows little to no threat on humans swimming in the region. The Nurse shark is also relatively abundant in the waters of the Bahamas and Florida. They are easily recognizable because of the fleshy appendages called barbels that hang below the nose and help detect prey. They are commonly between six and nine feet long and are one of the only sharks that often lie on the bottom of the ocean floor. Lastly the Lemon shark is also prevalent in the waters of the coasts of Florida and the Bahamas. They are mostly found in Florida’s southern waters around ship wrecks and ledges. It also can and often times does enter into estuaries and fresh water regions. Other sharks can be found in the waters of Florida and the Bahamas but these are the most common. These are not big sharks like the Bull and Great White sharks which often times are much more dangerous to humans.
Although the sharks of the region are not known as huge risks to swimmers, there are attacks in these waters by sharks. Although shark attacks at the millennium were on a rise throughout the world up almost 40 attacks since the decade before, 79 in 2000, a record, compared to 37 in 1990, since 2000 shark attacks have been on a decline, with only 55 unprovoked attacks last year (http://www.flmnh.ufl.edu/fish/Sharks/statistics/2003attacksummary.htm). In 2003, North America once again led the world in shark attacks with 65% of the worlds attacks taken place there. Florida was once again the leading place to get attacked by sharks with 31 attacks compared to second place Australia’s six. Almost half the attacks in Florida, 14, took place on the East coast in Volusia County which is where Daytona Beach is. For this class it should be noted that only 6% of attacks were on divers and snorkelers and only 7% of attacks overall in 2003 were fatal, and there were no fatalities in Florida (http://www.flmnh.ufl.edu/fish/Sharks/statistics/2003attacksummary.htm). Shark attacks may not be up from a decade ago because the sharks are getting more aggressive but simply because aquatic sports, such as surfing are growing in popularity. Florida and the Bahamas are going to have more attacks then let’s say the Northeast because more people swim in this area then up north and sharks are more abundant then in other regions; it’s simply just a numbers game. Also though in some areas of the Bahamas such as diving resorts sharks are lured in with food in order to make sure that the tourists will get to see the sharks they are paying money to see. Then while the sharks are feeding close to the tourists they might mistake an arm or a leg for prey. Although Florida is the leading region in shark attacks, many of the attacking sharks are small and do not carry a fatal bite like the bigger sharks found in Australia and South Africa. It should also be noted though that the annual risk of death from lightning is 30 times greater than that from a shark attack, but you don’t see major articles and movies about deaths by lightning.
Although sharks are known to attack, there are many myths out there about sharks and how they attack. The first commonly mistaken fact about sharks is that all of them are harmful to humans and have the ability to eat humans. This is entirely untrue, of the more then 350 shark species, about 80% are unable to hurt people or rarely encounter people. Another fact that is untrue but commonly thought of is the fact that sharks will eat anything that they get their jaws on. Actually most sharks prefer to eat specific types of invertebrates, fish and other animals. Some sharks eat mainly fish, while some eat other sharks or marine mammals and some even eat plankton. Another common mistake made about sharks is that they cannot function or live in fresh water. This is untrue in cases and one example is the bull shark that can survive in both waters that have low or high salt content. This means the shark has the ability to swim up rivers that may be fresh water. There is even a lake in Nicaragua that is home to fresh water sharks (http://www.mauigateway.com/~lechler/Sharks.htm#SEARCH). Sharks also have relatively large brains, which goes against the myth that they are just dumb, man eating machines. Surprisingly enough sharks can even be trained and have a brain capacity that is equal to a rat or a pigeon.
Lastly there are precautions that swimmers can take to help prevent the unlikely event that there is an interaction with a shark. Most of the ways to prevent a shark attack are commonsense, but sometimes as we know, commonsense is overlooked. First of all, always swim with someone else, never alone. Also don’t swim where large amounts of sharks congregate, like near channels, in between sandbars and at the mouths of rivers. Also never swim in murky or muddy water where the shark’s eyesight won’t be as good. Never swim where people are fishing or near a sewage outfall. Lastly if a shark is sighted in the area in which you are swimming, leave as calmly and quickly as possible. Most of these ideas are commonsense but take the right steps could save a life.
Ever since the movie Jaws in the late 1970’s, there has been a fascination with sharks. While going to the beach and swimming in the ocean are one of the more popular pastimes in American society, it is important that beachgoers have an understanding of sharks and their tendencies. Humans and sharks can easily live in the same environment without problems. Lastly always remember sharks are not man hunters and it is more common to be struck by lightning, then attacked by a shark.
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