Poster abstracts and manuscripts from the Third International ...

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difficulties associated with identification encountered by those
unfamiliar with beach trash and errors associated with our own
counts.
This result of only one such experiment does not necessarily
extend to the volunteer counts in general nor is it meant to
detract from the immense service done by the National Beach
Cleanups and their volunteers. The use of trained volunteers is
being considered in a nationwide effort to measure trends in
beach debris and it is hoped this study will contribute to that
effort.
Amos, Anthony F.
Marine Debris on a Texas Beach: Has MARPOL Made a Difference?
University of Texas Marine Sciences Institute, Port Aransas,
Texas, USA
The quantity of marine debris on Texas Gulf beaches has long been
a problem affecting several aspects of the beach environment:
aesthetics, tourism, public health, local economies and marine
animals. MARPOL Annex V, ratified by the U.S. in December 1987,
prohibits the disposal at sea of plastics and restricts the
disposal of other man-made debris. This regulation, and 'its
enforcement, promised to reduce beach litter and improve the
quality of the beach environment. This research sought to
quantify and categorize marine debris on a Texas beach both
before, and two years after, MARPOL Annex V went into effect.
Various categories of debris were counted along a 11.8 kilometer
(7.3 mile) stretch of Mustang Island Gulf beach, south of the
city of Port Aransas. Counts were made at eight-day intervals
from 1987 through 1989 and 1991 and 1992. Targeted item counts
have been made bi-daily from 1987 through the present. Items too
small to count were collected at three sites for one year in
1987/88 and 18 months in 1991/92. Dubbed "micro-trash," man-made
items were classified and weighed, as were associated natural
debris items. In an attempt to determine marine debris sources,
all containers found in a 0.25 kilometer stretch of neighboring
San Jose Island were collected monthly and classified by
material, container size, content, country of origin, weight and
volume..
Results show that many man-made items of marine debris have
diminished in quantity on the study beach in the post-MARPOL era.,
These include plastic sheeting, cardboard cartons, light bulbs,
milk jugs, egg cartons, glass bottles, Styrofoam pieces, 6-pack
yokes, cups and lids and 5-gallon pails. Remaining steady, or
increasing, were beverage cans, paper products, miscellaneousplastic
pieces and bleach bottles from Mexico. Circumstantially,