Transcript Historical Baselines for Large Sharks in Cape Cod, Massachusetts

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.