Biological Invasions of Cold-Water Coastal Ecosystems - Aquatic ...

Chapt 3. Biological Characteristics of Ballast Water, page 3- 15
Figure 3.6. Monthly densities of organisms in ballast water arriving to Port Valdez from domestic source
ports. The estimated mean densities (#/m³ and standard errors) are shown for all organisms, except chain-forming
diatoms, by month. The data for all domestic source ports are included in each month (sample size shown above
bars).
DENSITY (thousands/m³)
80
60
40
20
0
11
10
17 15 11 11
10
10 11 11 13 20
Jan Mar May Jul Sep Nov
SEASON
The seasonal pattern in total density varied among arrivals from the 3 major domestic
ports (Fig. 3.7). Arrivals from San Francisco Bay exhibited a strong spring peak in total
plankton density, whereas the peak appeared later in arrivals from Puget Sound. In contrast, the
density of organisms arriving from Long Beach was relatively stable throughout the year.
Figure 3.7. Monthly densities of organisms in ballast water arriving to Port Valdez by domestic source ports.
For each of the three major domestic source ports, the estimated mean densities (#/m³ and standard errors) are
shown for all organisms, except chain-forming diatoms, by month. Sample size for each source port as follows,
from left to right: Long Beach – 3,4,4,4,5,4,2,2,3,4,6,5; San Francisco –2,3,3,5,6,5,2,4,4,4,5,7; Puget Sound –
5,3,3,2,5,6,5,4,4,3,2,6.
DENSITY
(thousands/m³)
60
40
20
0
LONG BEACH
Jan Mar May Jul Sep Nov
DENSITY
(thousands/m³)
60
40
20
0
98.9
SAN FRANCISCO
Jan Mar May Jul Sep Nov
DENSITY
(thousands/m³)
60
40
20
0
PUGET SOUND
Jan Mar May Jul Sep Nov
SEASON