A mooring system was designed and constructed to make possible
the installation and the recovery of racks of sample panels for
a study of deep-ocean wood-boring molluscs. Racks containing
pine, fir, oak, and cedar boards were exposed to borer attack at
six stations with depths of 50, 100, 150, 200, 500 and 1000 meters,
all west of Depoe Bay, Oregon.
Two wood-boring molluscs, a pholad, Xylophaga washingtona
Bartsch, and a teredinid, Bankia setacea (Tyron), were recovered
from exposed wood materials. Xylophaga washingtona was the
dominant form and was found at all three deep stations. Bankia
setacea was found only at the 200-meter site and in very low numbers.
This reports the deepest known teredinid actively settling
and boring into a test board.
Borer attack increased in intensity with time, and in general,
decreased with increasing depth. Initial attack appeared to
commence right above the line where sample panels were in contact
with the sediment. Attack was heaviest in this zone and decreased
with increasing distance upward from the sea-sediment interface,
approaching zero in about 20 centimeters.
In general cedar was the most heavily attacked wood type
followed in turn by pine, fir, and then oak, which proved the most
resistant to xylophagan borers, The degree of maximum borer
penetration into any wood type correlated nicely with the density
of the wood, higher density wood being correspondingly most resistant
to borer attack. Degree of maximum borer penetration increased
with time and decreased with increasing depth.
The mooring system is fully described along with a summary
of field installation and recovery methods. Future research problems
are suggested. / Graduation date: 1968
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/28262 |
| Date | 03 May 1968 |
| Creators | Tipper, R. C. |
| Contributors | McCauley, James E. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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