EPA's Vessel General Permit and Small Vessel General

Sturgeon. Sturgeon species are also likely to be adversely affected by ANS species. Introduced
predatory ANS would prey on the eggs and juveniles of sturgeon. Other ANS (e.g., Asian clams,
zebra mussels, blue and flathead catfish) are likely to deplete sturgeon prey and/or compete for
sturgeon resources (US EPA 2012b). Introduced ANS are likely to expose sturgeon species to
viruses enzootic to the west coast of the U.S., spread diseases to these naïve populations (US
EPA 2012b). Therefore, shipping-related introduction of ANS is likely to reduce the survival of
individual sturgeon through predation, competition, and disease transmission.
Cetaceans
Cetaceans would be primarily exposed to ANS associated with vessel discharges through
changes in the abundance and distribution of their prey (trophic exposure).
Southern Resident Killer Whale. Southern Resident killer whales prey primarily on fish; salmon
are clearly the preferred prey, especially Chinook salmon during late spring to fall (Hanson et al.
2005, Ford and Ellis 2006). These whales consume salmon in large amounts to support
individual growth to reach sexual maturity and reproduction, including lactation and successful
rearing of calves (71 FR 69054).
As described above, ANS invasions are likely to reduce the fitness of individual threatened and
endangered salmonids. Sanderson et al. (2009) report that the impact of a devastating ANS
invasion is likely to equal or exceed that of all previously identified threats to salmon (i.e.,
habitat alteration, harvest, hatcheries, and the hydrosystem). In essence, ANS is likely to reduce
the abundance of salmonids, and the loss of its salmonid prey base is likely to reduce the survival
and reproduction of individual southern resident killer whales. In this manner, ANS invasions
are likely to reduce the fitness of Southern Resident killer whales.
Beluga whale (Cook Inlet DPS). Cook Inlet beluga whales feed primarily on Pacific eulachon
and salmonids. Pacific eulachon have a high fat content that confers a significant source of
energy for beluga whales, including calving whales that occur in the upper inlet during the spring
spawning (Calkins 1989). Like eulachon, salmon are another source of lipid-rich prey for the
beluga whale and represent the greatest percent frequency of occurrence of the prey species
found in Cook Inlet beluga whale stomachs (Hobbs et al. 2008). As described above, ANS
invasions are likely to reduce the abundance of Pacific eulachon and salmonids, and the loss of
the prey base of Cook Inlet beluga whales is likely to reduce the survival and reproduction of
individuals. In this manner, ANS invasions are likely to reduce the fitness of Cook Inlet beluga
whales.
Baleen whales. Microorganisms may constitute a majority of the species found in ballast water
(USCG 2012). Phytoplankton, particularly diatoms and dinoflagellates, can be especially
abundant and may cause the harmful algal bloom known as “red tides” (Carlton and Geller 1993)
or produce toxic compounds. Ballast water discharge containing ANS has contributed to the
increase in the frequency, intensity, and duration of harmful algal blooms in waters of the United
States (Hallegraeff 1993). Harmful algal blooms can produce toxic compounds, including
brevetoxin, saxitoxin and microcystins. Toxins can bioaccumulate in high trophic level marine
animals (Bushaw-Newton and Sellner 1999), with adverse effects ranging from cell and tissue
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