A person is more likely to be struck by lightning than to be attacked by a shark. However, it is still important to be wary when in the ocean and know how to reduce the risk of a shark attack. Sharks do not sleep the same way people do, as they have to keep swimming in order to move oxygen-rich water through their gills to survive. So when are sharks most active, and can sharks stop swimming? Sharks have active periods and resting periods that still allow them to swim constantly.
Shark feeding times are mainly at dusk and dawn. How often do sharks eat? Research suggests sharks will consume roughly one or two meals per week. With this in mind, it is smart to avoid going into the ocean at dawn and dusk to minimize the risk of a run-in with a shark. Also, it is imperative not to swim in an area with schools of fish or where someone is fishing.
The fish attract sharks to the area and increase the risk of coming across one. It is especially important to avoid areas of sewage, runoff or possible concentrations of baitfish, as these areas may be feeding spots for the sharks. Shark feeding time is generally at dusk and dawn, but there are other factors that may attract a shark your way. They will seek out prey that is isolated more quickly than those that are not. Swimming in the ocean at night can pose a greater risk than swimming during daylight hours, especially for inexperienced swimmers.
This is due to the loss of vision in the darkness, the lack of people nearby, and the nocturnal behavior of ocean predators. Water pollution at the beach can cause many sicknesses, keeping you out of the water and potentially creating long-term health issues. Illnesses associated with polluted beachwater include stomach flu, skin rashes, pinkeye, respiratory infections, meningitis, and hepatitis.
Begin typing your search term above and press enter to search. Mighall was one of roughly 83 people around the world to be attacked unprovoked by sharks in It is a figure that has remained around the same level over the past decade.
The average number of unprovoked attacks between , for example, was But recent research indicates that shark attacks in some parts of the world appear to be on the rise. The eastern US and southern Australia have seen shark attack rates almost double in the past 20 years , while Hawaii has also seen a sharp increase. But why? This seems like an obvious point, but when you look closer at where attacks are taking place there are some clues as to what might be going on.
The large human populations along the southern coast of Australia and the eastern coast of the US mean large numbers of people enjoying the water. But southern Australia has also seen rising numbers of fur seals along its coastline, the favourite prey of great white sharks in the region. The resurgence in seal populations on Cape Cod on the east coast of the US has led to rising numbers of great white sharks in areas popular with people Credit: Getty Images.
This has led to increased numbers of great whites in the area too during the warm summer months as they look to feast on the seals that pull themselves out to bask on the beaches. Sadly, last autumn, Massachusetts suffered its first fatal shark attack in 82 years and growing numbers of shark sightings have led to a string of beach closures.
But there is no real evidence that sharks are actively hunting humans, according to the scientists who study them. Great whites in the North Atlantic, for example, show seasonal movement patterns, migrating thousands of miles to warmer waters further south during the winter months. Some mature adults will venture out into the open ocean for months at a time , covering tens of thousands of miles and diving to depths of 1,m as they seek prey.
But despite being potentially such an easy meal, sharks are really not that interested in hunting humans. I think if people knew how frequently they were in water with sharks, they would probably be surprised.
However, Naylor believes that the official statistics on shark attacks are probably an underestimate. Most reports come from highly developed countries with large populations and highly active news media.
Attacks on remote islands or in less developed communities probably go unreported. Looking at the statistics for the number of shark attacks last year can reveal some fascinating trends. Just four of these were fatal according to the International Shark Attack File, although another database of shark attacks records seven deaths. So far in , there have been four fatal shark attacks. Tiger sharks are one of the three main species responsible for attacks on humans but much of the time they ignore people in the ocean Credit: Getty Images.
The reason for the fall — which bucks the overall trend of growing numbers of attacks — has been attributed to a sharp decline in the number of black-tipped sharks. These sharks account for many of the bites around the south-eastern US, migrating down the coast of Florida due to rising sea temperatures that have led their prey to become more dispersed.
The findings highlight one of the key challenges in understanding why sharks bite humans. There are dozens of different species responsible for bites , each with their own unique behaviour, hunting strategies, prey and preferred habitat — although in many cases the species can be misidentified or not identified at all.
The majority of unprovoked attacks on humans where a species is identified involve three large culprits: the great white, tiger and bull sharks. Great white sharks are considered to be the most dangerous species in the oceans today, but we still know very little about their life cycle and behaviour Credit: Getty Images. Bull sharks, for example, tend to hunt in shallow, murky water that will require them to rely less on vision and more upon their sense of smell and electroreception, which allows them to detect minute electrical fields produced by their prey.
There is also some evidence that shark teeth may also function as mechanosensory structures — similar to touch — to help the animals learn more about what they are biting. Chapman believes there may be a complex set of reasons for why unprovoked attacks on humans appear to have risen in recent decades.
In , for example, there was a sudden spate of shark bites off the coast of Recife, Brazil — an area that had no unprovoked attacks for the entire previous decade.
Winton and Skomal said the study was a first step in what they hoped would be the conclusion of a number of studies underway that could fill in pieces of the shark behavior study and contribute to public safety. Woods Hole Sea Grant has funded research that will merge existing data from over tagged sharks with satellite temperature and water clarity data to determine the conditions under which they prefer to hunt, in terms of the balance between their visual ability to see prey but not be seen.
Another study done in collaboration with the Center for Coastal Studies will continue this summer. While the recently published research paper speaks to white sharks spending a lot of time in shallow water, this study will look at what they do there by using a grid of acoustic receivers set up off Head of the Meadow Beach in Truro and one off Nauset Beach in Orleans to determine exact depth and position, along with specialized tags that measure acceleration and body position as the shark hunts seals.
Extensive mapping of the bottom at these locations will tell researchers how the sharks use bottom features such as channels and sandbars to travel and hunt, which will help inform the public about places where sharks are more likely to be hunting seals.
Winton said researchers were getting close to completing data analysis on a long-awaited, five-year population study.
The group advocates for more study and funding leading to solutions and technologies that provide greater safety for those who use the ocean. Papadonis uses a shark deterrent system on his own surfboard that aggravates the white sharks' electronic navigation and prey-detection organs.
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