- What are the most common shark species in Virginia waters?
- What is the conservation status of sharks?
- What is the focus of shark research at VIMS?
- Why are sharks important ecologically?
Sharks and People
- How common are shark bites?
- Where are shark encounters most common in the U.S.?
- Are shark bites becoming more common?
- How can one minimize the already low risk of a shark bite?
Shark populations were severely overfished by both recreational and commercial fisheries from the late 1970s to the early 1990s. Data from the VIMS Shark Survey show that sandbar sharks were reduced by 65%, and duskies by 80%. The implementation of shark management measures in Virginia in 1990, and by the Federal Government in 1993, have led to a slow but steady recovery in most mid-Atlantic shark stocks. Sharks are susceptible to over-fishing because they grow slowly, reach sexual maturity at an advanced age (6-21 years for most of the larger species), and produce only 8-10 pups every other year. The lower Chesapeake Bay and the lagoons along Virginia's Eastern Shore constitute the principal nursery grounds for sandbar sharks. This is the most abundant large shark species on the Atlantic Coast, and the most important in both recreational and commercial fisheries. [top]
The VIMS Shark Survey, established by Dr. Jack Musick, has been monitoring populations of adult sharks in the Chesapeake Bight using standardized, fishery-independent longline surveys since 1973. This long-term data set represents the longest running fishery-independent shark-monitoring program in the world. The Shark Survey is now part of VIMS broader Virginia Shark Monitoring and Assessment Program (VASMAP), which also includes a juvenile COASTSPAN survey and shark tagging studies. Scientists and students involved in these programs provide detailed analyses of habitat use, age, growth, reproduction, trophic dynamics, and demographics of commercially, recreationally, and ecologically important shark species in the mid-Atlantic region. Data from the VIMS Shark Survey figure prominently in the Federal stock assessments for sandbar and dusky sharks. [top]
Sharks sit atop the food chain as apex predators. As such, they play an important ecological role in keeping prey populations healthy by removing weak, old, and infirm individuals. When shark populations decline due to over-fishing and habitat loss, prey populations can increase unchecked, leading to an overall decline in ecosystem health. [top]
Encounters with sharks are extremely rare. An individual is three times more likely to be hit by lightning than to be bitten by a shark. There were an average of 70 shark bites a year between 2005-2014 in the entire world. Less than 10% of these were fatal. Visit the International Shark Attack File for a comparison of the relative risk of shark bite versus other potential hazards. [top]
In the U.S., most encounters with sharks occur in Florida. Incidents in Virginia are extremely rare and incidents in North Carolina are uncommon. There are only 5 unprovoked shark bites on record in Virginia, with only one fatal bite, in 2001. There have been 52 bites in North Carolina between 1990 and 2004, 4 of them fatal. For a comprehensive database of shark-attack statistics, trends, and analyses, visit the International Shark Attack File. [top]
Long-term trends in the prevalence of shark-human interactions are directly correlated to human population and interest in marine recreation. Because more humans are spending more time in the ocean, the number of shark-human interactions and other marine-related injuries is generally increasing. Increased media coverage and scientific interest has also led to an increase in the number of shark-human interactions that are recorded. Sharp declines in shark populations during recent decades in many areas of the world as a result of over-fishing and habitat loss reduce the potential for shark-human interactions. Local year-to-year variations in economic and social factors, weather, and ocean conditions significantly influence the abundance of sharks and humans in the water. As a result, short-term changes in the number of shark attacks—up or down—must be viewed with caution. Scientists prefer to view trends over longer periods of time (e.g., by decade) rather than trying to assign undue significance to year-to-year variability. (adapted from ISAF statment). [top]
Avoid being in the water when sharks are most likely to be present. Sharks generally feed around dawn and dusk and often move into shallow waters following prey such as menhaden and other small fish. When schools of bait fish are observed near the shoreline sharks and other predators may also be nearby. Along the coast of the U.S. sharks move north in the spring with warming temperatures, and south again in the fall as water temperatures cool.
To minimize the chance of a shark encounter, experts recommend the following precautions:
- Swim between the hours of 9 am and 5 pm
- Remove jewelry and other shiny accessories before entering the water
- Avoid murky or cloudy waters
- Refrain from swimming alone
- Remain relatively close to the shore and in an area monitored by a lifeguard
- Avoid swimming near fishing activities (e.g., fishing piers, surf casting, seine operations, etc.)
- Maintain an awareness of your surroundings