Marine Mammal Populations and Ocean Noise Determining When Noise Causes Biologically Significant Effects (2005) / Chapter Skim
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4 Rational Management with Incomplete Data
4 Rational Management with Incomplete Data
Pages 69-86
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From page 69... ...
The three acts of Congress most relevant to regulating exposure of marine mammals to noise are the National Environmental Policy Act of 1969 (NEPA) , the Marine Mammal Protection Act of 1972 (MMPA)
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From page 70... ...
Extensive modeling and sensitivity analysis confirmed that the selected parameter values ensured, with high probability, that the population impacts would be within the prescribed bounds. Anyone who feels that the allowed removals are set either too low or too high can present new data and interpretation in peer-reviewed publications that NOAA Fisheries uses in stock assessments and establishment of PBR.
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From page 71... ...
POTENTIAL BIOLOGICAL REMOVAL The 1994 reauthorization of the MMPA introduced a new regime to determine when the number of animals killed or seriously injured by commercial fisheries poses a risk to marine mammal stocks. It involves estimating the number of animals that could be "removed" from a marine mammal stock without stopping the stock from reaching or maintaining its optimal sustainable population (16 U.S.C.
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From page 72... ...
· There is a mechanism for demonstrating that decisions based on the model meet the MMPA management goals. Before 1994, the MMPA prohibited any kills of marine mammals in stocks that were below an optimal sustainable population (OSP)
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From page 73... ...
· Populations at high risk will not be delayed in reaching OSP numbers by more than 10% beyond the predicted time that is based on an absence of human-induced mortality. Biologists at NOAA Fisheries tested various values for the input parameters to decide on the values most likely to meet management goals.
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From page 74... ...
There may be additional uncounted lethal takes from a variety of sources, including exposure to intense noise. The potential for such takes of Cuvier's beaked whales in association with naval sonar was reflected in the NOAA Fisheries 2002 stock assessment for Cuvier's beaked whales in the western North Atlantic.
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From page 75... ...
However, as currently implemented, the PBR mechanism cannot adequately protect marine mammals from all sources of human-induced mortality until all such mortality is included in a revised and expanded PBR regime. RECOMMENDATION 7: Improvements to PBR are needed to reflect total mortality losses and other cumulative impacts more accurately: · NOAA Fisheries should devise a revised PBR regime in which all sources of mortality and serious injury can be authorized, monitored, regulated, and reported in much the same manner as is currently done by commercial fisheries under Section 118 of the MMPA.
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From page 76... ...
To address Recommendation 7, NOAA Fisheries could convene an expert panel of veterinarians to assign injury severity scores for those and other symptoms. For example, it seems likely that the first category might score 0.3, the second category 0.1, and the third category 0.01.
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From page 77... ...
cal time or in a critical place when a specific activity must occur (for example, it disrupts a critical feeding trip of a phocid seal or disturbs a breeding site during a short season) , the severity score will be higher.
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From page 78... ...
Table 4-1 illustrates the expectation that the higher the severity score, the fewer animals expected to be impacted, but in addition it illustrates how leaving out the cumulative effects of injury and harassment may underestimate cumulative impacts. In this hypothetical example, with an unrealistic assumed density of 1 animal/ 3.14 m2, there is 1 lethal take, the equivalent of 1 lethal take in 10 injuries, and the equivalent of 1 lethal take in 100 cases of behavioral harassment.
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From page 79... ...
Prior sections of this report have emphasized the long time-line for acquiring the data and understanding necessary for a full implementation of the PCAD model. Compliance with the current regulatory interpretations of the NEPA, the MMPA, and the ESA is fraught with uncertainty regarding the use of sound sources in the marine environment and as the 2000 National Research Council report noted, regulations are more effective when they target critical disturbances.
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From page 80... ...
require a permit or may be considered exempt from permitting. Essentially, such a process would allow regulators to establish de minimis standards that identify activities that have a low probability of causing changes in marine mammal behavior that would lead to significant population effects.
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From page 81... ...
The initial stage in evaluating whether potential effects of a sound source cross the de minimis threshold would use the NOAA Fisheries acoustic criteria described in Chapter 3. For each species in the area, the exposure to sound from the planned sources is evaluated in terms of the criterion threshold for sound pressure level or energy level for the functional hearing group to which the species belongs.
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From page 82... ...
For example, female marine mammals can be divided into capital breeders, which postpone reproduction until they have stored enough energy to carry infants through to weaning, and income breeders, which continue to make foraging trips during lactation (Costa, 1993)
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From page 83... ...
For behavioral changes that alter the response to predators, very low thresholds are recommended if there is the chance that the disruption will increase the vulnerability of an animal to predation. Many marine mammals depend on social defenses from predation (Mann et al., 2000)
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From page 84... ...
Such a system, if applied to all activities, would provide rich opportunities for epidemiological analyses of the data to identify hot spots and linkages between human activities and marine mammal mortality or morbidity. Any cases of lethal take or serious injury should be reported immediately and should be added to the take that is compared with the PBR.
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From page 85... ...
The PCAD model and proposed revisions to the PBR will take years to implement. In the interim, those who introduce sound into the marine environment and those who have responsibility for regulating takes resulting from such activities need a system whereby reasonable criteria can be set to determine which sounds will have a nonsignificant impact on marine mammal populations.
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