Poster abstracts and manuscripts from the Third International ...

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SESSION I POSTER MANUSCRIPTS
Amounts, Types and Distribution of Marine Debris
Baba, Norihisa and Masashi Kiyota
Distribution and Characteristics of Marine Debris in the North
Pacific Ocean, 1989-1990
National Research Institute of Far Seas Fisheries, Fisheries
Agency, Shimizu, Japan
Abstract
Distribution and characteristics of marine debris in the North
Pacific and in the Bering Sea were studied using sighting data
collected at 77 daily transect lines from June to August in 1989
and 1990. Total distance surveyed was 17,125 km and the sighting
area was a total of 6,850 km 2 . Petrochemical products (e.g.,
nylon, Styrofoam, vinyl, polyethylene goods etc.), composed 76.2%
of the total of 3,440 pieces of debris sighted. Other debris
consisted of glass (3.2%), metal (1.3%), wood (10.7%) and natural
log (8.6%). Fishing debris accounted for 18.3% of the total
petrochemical debris; gillnet floats alone accounted for 15.0% of
the total petrochemical debris. 'Fishing net fragments were minor
components of the total of marine debris observed. They were
observed mainly in the central North Pacific. Density
(number/km 2 ) of marine debris was high in the coastal areas off
northern Japan and off North America, and low in the Bering. Sea,
offshore areas off Alaska, Kamchatka, and Kurile Islands. The
highest densities of marine debris occurred in the central North
Pacific northeast of the Hawaiian Islands. These data, suggest
that marine debris in the North Pacific may be concentrated in
the northeastern area off Hawaii by a large gyre current.
Introduction
Convenient goods, such as plastic, vinyl, Styrofoam etc., have
been created as human life developed, and these manmade products,
have been accumulating in the ocean. Many surveys and education
programs on marine debris have been conducted and their results
were reported at the 1st and 2nd Marine Debris Conferences held
in Hawaii in 1984 and 1989, respectively. Mio et al. conducted a
sighting survey of marine debris in the North Pacific and
reported that density of marine debris was high in the coastal
area of land and in the area between 25°N-30°N and 170°W-13O°W.
Furthermore, Day et al. reported that highest density of marine
debris generally occurred in the Japan Sea and near shore Japan
Water, Transitional Water, and Subtropical Water. Matsumura et
al. estimated that floating debris may gather in the eastern and
western regions of the mid-Pacific, though nobody surveyed those
places. Objectives of this study were to study the distribution
and characteristics of marine debris in the North Pacific and
Bering Sea, and to confirm whether or not marine debris in the
North Pacific gathers in the northeastern area off Hawaii.