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Historical baselines for large sharks in Cape Cod, Massachusetts (USA): Putting recent observed increases into context Elizabeth McCormack & Loren McClenachan, Environmental Studies Program, Colby College (Contact: [email protected]) Abstract: Over the last decade, observations of sharks in the waters around Cape Cod have increased, suggesting population increases. Historical data can help to put these recent increases into a long-term context. Using newspaper articles, photographs, and other observations, we compiled historical data on sharks in the waters around Cape Cod from approximately a 100 year period, from 1830 to 1940 to compare to modern observations. As well, we document trends in commercial and cultural value of sharks in New England in the early 19th century. Such historical baselines are essential to put recent observations into a long-term context, as well as to begin to understand ecosystem dynamics and the relationship between people and conservation-dependent marine animals over longer time scales. Results To examine recent trends, we searched the Cape Cod Times online database for articles referencing local observations of sharks in the waters around Cape Cod, Massachusetts. To examine historical trends we searched five historical archives on Cape Cod and in Boston for local observations of sharks from 1830-1940. Recent Trends: There was an increase in articles on sharks in the Cape Cod Times over the past 16 years, with 34 articles in the five period from 2001-2005 and 257 in the five year period from 2009-2013. Recent articles describe shark sightings, predation on seals, and the perception that populations are increasing. The focus of these articles is on the globally Endangered white shark (Caracharodon carcharias) and may reflect overall cultural interest in large, pelagic sharks. 100 3500 Articles in the Cape Cod Times from 1997 to 2013 3000 2500 80 2000 60 1500 40 1000 20 500 2013 2009 2010 2011 2012 2005 2006 2007 2008 0 1997 1998 1999 2000 0 2001 2002 2003 2004 Number of articles about sharks (bars) 120 Total number of articles in database (line) Methods Year Shark caught in gill net, photo taken at the Plymouth Town Pier in 1938. Photo credit: Skip DeBrusk. Targeted catch: Articles describing sharks caught in 1918, Sturgis Library of Barnstable . Man with sharks in family photo album in 1936, Provincetown History Preservation Project. Year Examples of Recent Shark Observations Location 1997 Injured seal pup on shore, probable shark attack. Report of big shark prompts coast alert: patrolling after white shark attacks a 20-foot charter boat. Seal population explosion possible explanation for increasing shark observations. Cape kayakers report shark vs. seal attack: kayakers witness shark attack seal between Chatham and Monomoy Island. Great whites return to Cape in force: three sightings between Chatham and Truro and one possible sighting near Nantucket. Man apparently bitten by shark off Truro: at Ballston Beach. Shark sighting closes Chatham beach: 20-foot female shark was tagged and receiver buoys indicate more sharks near Chatham. Unreported 2001 2004 2009 2009 2012 2012 Chatham, MA Chatham, MA Chatham, MA Multiple Truro, MA Chatham, MA Historical Trends We found 54 newspaper articles & photographs on Cape Cod from1830 to 1940, which included descriptions of: Year Examples of Historical Shark Observations Location 1830 A whale followed by several sharks near the Bass River.1 South Yarmouth, MA 1858 Unreported Abundance: Throughout our historical time period, sharks were described as abundant, with large groups observed from shore. For example, a 1830 article described a whale followed by several sharks near the mouth of a local river, and a 1921 describes ‘schools of sharks’ seen from shore in Nantucket. 1878 1884 1916 1918 Large shark tangled in fisherman's nets, 9-10 feet 800 pounds.1 Describes sharks as man eating, boat followers that will eat anything thrown overboard.1 16-foot shark caught near central wharf.1 Call from the Marine Commissioner to "make war" on sharks because they deplete "food fish" and consume more "food fish" than men.1 Federal legislation from the Fish and Game Commission to exterminate sharks; steel nets around beaches proposed. 2 300 sharks landed at R.R docks- gas boats Effie L. and Helen. 3 1920 Gas Boat One Boy lands 200 sharks on R.R dock. 1 Unreported 1921 Schools of sharks seen off shore. 1 The Ocean Leather Company (Newark, NJ) applied for a permit to operate a shark industry on Railroad Wharf, Hyannis.3 Shark attack kills local boy in Buzzards Bay.2 12' and 17' sharks killed by fishing crews. 2 Nantucket, MA Cultural value: Sharks were described harmful to public safety and local fish stocks. An article from 1878 describes sharks as ‘man-eating, boat followers that will eat anything thrown overboard.’ Extermination: Due to their perceived abundance and competition for fish, federally sponsored culling of sharks was implemented. In 1916 the Fish and Game Commission passed federal legislation to exterminated sharks in North Atlantic coastal waters. 1915 1924 1936 1936 1 Barnstable Patriot 2 Boston Globe 3 New England New England Unreported Hyannis, MA Mattapoisett, MA Unknown Hyannis Patriot Discussion Targeted catch: Following this legislation, large numbers of sharks were reported as landed on Cape Cod. We found articles describing seven shark fishing trips between1918 and1920, which landed between 13 and 300 sharks each with a total reported catch of 761 sharks. In this same time period, the Ocean Leather Company applied for a permit to operate a shark processing plant in Hyannis. Incidental catch: During the whole period, sharks were caught incidentally. For example, articles describe a 16-foot shark caught in Wellfleet, MA in 1915 and 12 and 17 foot sharks caught in 1936. Reports of incidental catch more frequently Acknowledgements: We would thank the Colby College Dean include species information thanlike dotoreports of targeted catch. of Faculty’s Office for funding this project. Chatham, MA Wellfleet, MA Incidental catch: White shark (‘man-eater’) speared from shore in 1860, Provincetown Hist. Pres. Project. • While modern observations suggest that shark populations are increasing on Cape Cod, historical documents indicate that they were abundant in the past, with hundreds killed as part of extermination program in early 20th century. • Reports of incidental catch often include descriptions that allow identification of species, but we are largely unable to differentiate species caught in large numbers as part of the targeted fishery. • Comparing the two sets of newspaper articles documents a shift in cultural value of sharks, from pests to species with ecological and intrinsic value.