Composite Training Unit Exercises and Joint Task ... - Govsupport.us

COMPTUEX/JTFEX EA/OEA Final Chapter 4of the sound exposure, and the context in which the sound is presented. However, to provide a tractableapproach to predicting acoustic effects that is relevant to the terms of behavioral disruption described inthe MMPA, it is assumed here that the severities of behavioral effects also decrease with decreasingsound exposure and/or increasing distance from the sound source.4.3.1.7.6 MMPA Level A and Level B HarassmentCategorizing potential effects as either physiological or behavioral effects allows them to be related to theharassment definitions. For military readiness activities, Level A harassment includes any act that injuresor has the significant potential to injure a marine mammal or marine mammal stock in the wild. Injurydefined in previous rulings (National Oceanic and Atmospheric Administration [NOAA], 2001; 2002), isthe destruction or loss of biological tissue. The destruction or loss of biological tissue will result in analteration of physiological function that exceeds the normal daily physiological variation of the intacttissue. For example, increased localized histamine production, edema, production of scar tissue,activation of clotting factors, white blood cell response, etc., may be expected following injury.Therefore, this EA/OEA assumes that all injury is qualified as a physiological effect and, to be consistentwith prior actions and rulings (NOAA, 2001), all injuries (slight to severe) are considered Level Aharassment.Public Law 108-136 (2004) amended the definition of Level B harassment for military readinessactivities, which applies to this action. For military readiness activities, Level B harassment is defined as“any act that disturbs or is likely to disturb a marine mammal or marine mammal stock by causingdisruption of natural behavioral patterns including, but not limited to, migration, surfacing, nursing,breeding, feeding, or sheltering to a point where such behaviors are abandoned or significantly altered.”Unlike Level A harassment, which is solely associated with physiological effects, both physiological andbehavioral effects may cause Level B harassment.MMPA Harassment ZonesThe volumes of ocean in which Level A and Level B harassment are predicted to occur are described asharassment zones. All marine mammals predicted to be in a zone are considered exposed to harassmentwithin the applicable harassment category. Figure 4.3-1 illustrates harassment zones extending from ahypothetical, directional sound source. (This figure is for illustrative purposes only and does not representthe sizes or shapes of the actual harassment zones).The Level A harassment zone extends from the source out to the distance and exposure at which theslightest amount of injury is predicted to occur. The acoustic exposure that produces the slightest degreeof injury is therefore the threshold value defining the outermost limit of the Level A harassment zone.Use of the threshold associated with the onset of slight injury as the most distant point and least injuriousexposure takes account of all more serious injuries by inclusion within the Level A harassment zone.4-21 February 2007