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Life HistorySharks belong to the class Chondrichthyes (cartilaginous fish) that also includes rays, skates and deepwater chimaeras (ratfishes). Relative to other marine fish, sharks produce few young in their lifetime. The low reproductive rate is due to slow growth, late sexual maturity, one to two-year reproductive cycles, a small number of young per brood and specific requirements for nursery areas. These biological factors leave many species of sharks vulnerable to overfishing. Some sharks bear live young (pups) and some species lay eggs. Females produce a small number (2 to 25) of large pups, which have an increased chance of survival due to their size. Adults usually gather in specific areas to mate and females travel to specific nursery areas to pup. These nursery areas are discrete geographic areas, usually in waters shallower than those inhabited by the adults. Frequently, the nursery areas are in highly productive coastal or estuarine waters where small fish and crustaceans (shrimp and crabs) are abundant to provide food for the growing pups. These shallow areas have fewer large predators than deeper waters, thus enhancing the chances of survival of the young sharks. Sharks are a vital part of the ocean all over the world. Scientists consider them to be a keystone species because they generally reside at the top of the food chain having, a strong impact on other species either directly or indirectly. Removing or reducing shark populations in an area can cause an imbalance in the food chain and produce far reaching negative impacts within the ocean environments. Because of this, the condition of sharks is often an accurate indicator of the overall health of areas in the ocean. FisheriesThe commercial shark fishery, including smooth dogfish, is generally concentrated in the Southeastern United States and Gulf of Mexico. The Atlantic fishery targets both large coastal shark and small coastal shark species with bottom longline as the primary commercial gear, followed by gill nets. An Atlantic bottom longline is 3.4 miles in length on average and contains about 300 hooks. Skates, other sharks, or various finfish are used as bait. The gear typically consists of a heavy monofilament main line with lighter weight monofilament gangions, or branch lines, coming off the main line. The Southeast shark gill net fishery typically uses nets ranging from 1,459 to 7,480 feet long and 20 to 758 feet deep, with about 5.2 inches of stretched mesh. Commercial coastal shark landings in North Carolina have fluctuated in the past 10 years (Figure 1) while smooth dogfish landings have declined (Figure 2). Coastal shark landings in 2016 reached the second highest in the time series. The recreational fishery for Atlantic sharks occurs in federal and state waters from New England to the Gulf of Mexico and Caribbean Sea. Once called "the poor man's marlin," recreational shark fishing is now a popular sport at all social and economic levels, largely due to accessibility to the resource. Sharks can be caught by rod and reel virtually anywhere in saltwater, with even large sharks available to surf anglers or small boaters in the nearshore area. Most recreational fishing takes place from small to medium size vessels. Small coastal shark species such as Atlantic sharpnose, bonnethead and finetooth comprise most of the recreational harvest (Figure 3). Large coastal shark recreational harvest has not fluctuated significantly, but releases have, with a peak in 2015 (Figure 4). Popular recreationally caught open water (pelagic) sharks include the shortfin mako and common thresher and are generally accessible only to those aboard ocean-going vessels. No recreational harvest of pelagic sharks was recorded in 2016 but releases were the highest in the time series. Smooth dogfish are the only species from the smoothhound shark complex occurring in the Atlantic Ocean. Smooth dogfish comprise most of the recreational live releases.
ManagementIn the early 1990s, the National Marine Fisheries Service implemented a Fishery Management Plan for Sharks of the Atlantic Ocean to rebuild depleted stocks and keep the rate sharks are removed from populations in check. In 2008, the Atlantic States Marine Fisheries Commission adopted an Interstate Fishery Management Plan for Atlantic Coastal Sharks (and later Addenda I-IV to the plan) to complement federal management actions and provide protection of pregnant females and juveniles in inshore nursery areas. The plan regulates 40 different species of coastal sharks found on the Atlantic coast. Addendum I (2009) modified recreational possession limits for the smoothhound shark complex and other species, allowed at-sea processing of smooth dogfish from March to June, and removed the two-hour net check requirements. Addenda II and III (2013) addressed changes in the federal management of coastal sharks. Addendum II allocated state-shares of the smoothhound shark complex coastwide quota and modified the maximum fin to carcass ratio, consistent with the Shark Conservation Act of 2010. Addendum III created two new species groups (Hammerhead and Blacknose) and increased the recreational size limit for hammerheads. Addendum IV allowed smooth dogfish carcasses to be landed with their corresponding fins removed from the carcass as long as the total retained catch, by weight, is composed of at least 25 percent smooth dogfish, consistent with federal management measures. Stock Status OverviewStock status is determined by species group or by species complex if there is not enough data for an individual assessment by various federal agencies (Table 1). Fourteen species have been assessed in the United States, three species have been reviewed internationally, and the rest (28 species) have not yet been evaluated. Most of the species require a stock assessment or an updated stock assessment due to new data, changing information on stocks and improved assessment methods. Research NeedsData and research needs for coastal shark species currently assessed include updating age, growth, and reproductive studies and determining gear specific post release mortality estimates. For coastal shark species not assessed, data and research needs include determining life history information for data poor species and using genetic, conventional, and electronic tags to determine appropriate management units. Additionally, research needs for all coastal shark species managed include developing monitoring programs to collect appropriate length and age samples from the catches in the commercial sector by gear type, from catches in the recreational sector, and from catches taken in the research surveys to provide reliable length and age compositions for stock assessment.
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