This paper reviews current aquatic farm production in the USA and estimates
an annual financial exposure of US$350 million in the marine and coastal e
nvironments made up of sales, standing crop value and capital investment. I
n addition, nationwide aquatic fanning creates almost 200,000 jobs and, wit
h secondary and downstream activities combined, contributes about US$5600 m
illion to the GNP. The paper then reviews the increasing risk that elements
of the coastal aquaculture industry in the Pacific Northwest face from int
eractions with populations of marine mammals. These are particularly Califo
rnia sea lions and seals, which have greatly increased in the last 20 years
from California to British Columbia. Specifically: (i) shellfish from trad
itional beds have been contaminated by fecal coliforms from seals and made
unfit for human consumption, and have been experiencing increasing losses t
o river otters and sea otters; (ii) culture-based salmon fisheries, includi
ng endangered salmon stocks, have been exposed to heavy predation by sea li
ons and seals, resulting in both direct losses and reduced market value of
wounded survivors; (iii) net-pen farms have been exposed to the same heavy
losses from predatory sea lions and seals attacking fish in the pens, toget
her with added financial burdens for anti-predator nets, increased maintena
nce and labor; and (iv) workers in aquaculture and fisheries, and other wat
erborne industries, have been observing less fear of humans by sea lions an
d seals, and more direct damage to servicing facilities. The four issues ar
e discussed both technically and economically, and a number of solutions pr
oposed for managing and controlling these increasing risks. (C) 2000 Publis
hed by Elsevier Science B.V.