NMFS Biological Opinion on U.S. Navy training ... - Govsupport.us

FINAL PROGRAMMATIC BIOLOGICAL OPINION ON U.S. NAVY ACTIVITIES IN THE HAWAII RANGE COMPLEX 2008-2013
Integration and Synthesis of Effects
In the Assessment Approach section of this <strong>Opinion</strong>, we stated that we measure risks to individuals of endangered or
threatened species using changes in the individuals’ “fitness” or the individual’s growth, survival, annual
reproductive success, and lifetime reproductive success. When we do not expect listed plants or animals exposed to
an action’s effects to experience reductions in fitness, we would not expect the action to have adverse consequences
on the viability of the populations those individuals represent or the species those populations comprise (Anderson
2000, Mills and Beatty 1979, Brandon 1978, Stearns 1977, 1992). As a result, if we conclude that listed plants or
animals are not likely to experience reductions in their fitness, we would conclude our assessment.
The following discussions summarize the probable risks the training exercises and other activities the U.S. Navy
plans to conduct in the Hawai'i Range Complex each year for the next five years pose to threatened and endangered
species that are likely to be exposed to those transmissions. These summaries integrate the results of the exposure
and response analyes we presented previously with background information from the Status of the Species section of
this <strong>Opinion</strong> to assess the potential risks the training is likely to pose to endangered and threatened individuals, the
population or populations those individuals represent, and the “species” that have been listed pursuant to the
Endangered Species Act of 1973, as amended.
BLUE WHALES. During future Rim of the Pacific Exercises, the first scenario (which assumed that animals would not
move) identified 140 instances in which blue whales might be exposed to mid-frequency active sonar at received
levels between 140 and 195 dB and no instances in which blue whales might be exposed at received levels between
195 and 215 dB. During the other anti-submarine exercises (USWEX, TRACKEX, and TORPEX) the U.S. Navy plans to
conduct in the Hawai’i Range Complex each year, the first scenario identified another 351 instances in which blue
whales might be exposed to mid-frequency active sonar transmissions at received levels between 140 and 195 dB.
No blue whales would be exposed to received levels greater than 195 dB associated with these other training
activities.
Of the 489 instances in which <strong>NMFS</strong>’ exposure models identified blue whales that might be exposed to midfrequency
active sonar at received levels between 140 and 195 dB, about 286 of those instances would involve
exposures at received levels between 140 and 150 dB. Another 136 of those instances would involve exposures at
received levels between 150 and 160 dB. The balance of the exposures would occur at received levels greater than
160 dB.
As discussed in the introduction to our Exposure Analyses, it is important to note that these estimates probably overestimate
the actual number of blue whales that might be exposed to one or more of the activities the U.S. Navy plans
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