determination of OSP as it can. Its proposed definition is as follows: "Optimum sustainable population" is The outer limits of the range described in this definition thus appear to be the familiar MSY level and a hypothetical unexploited population level. While such a definition would clearly permit the maintenance of marine mammal populations at levels above MSY, it would also allow their maintenance at MSY levels. In light of the ample legislative history that Congress thought it was directing the abandonment of the MSY management standard, the proposed definition seems subject to question.57/ The skirmishes over how the administering agencies choose to define OSP will probably be less important in 56/ 571 41 Fed. Reg. 44049 (Oct. 6, 1976). The best explication of the legislative history of the development of the OSP standard can be found in Gaines & Schmidt, supra note 9 at 50103-08. The Marine Mammal Commission apparently endorses the proposed definition of the National Marine Fisheries Service as an interim definition pending the development of further information which would permit the narrowing of the range. See Marine Mammal Commission, supra note 53 at 7. However, the Commission emphasizes the difficulty of establishing precisely both actual existing population levels and MSY levels, and therefore suggests that a safety factor be included in estimates of such levels. Id. at 8-9. the long run than the question of how much justification the courts will require to support its application in any particular instance. To date, it is at least clear from Committee for Humane Legislation, Inc. v. Richardson that the courts will not permit such agencies to ignore the requirement to determine OSP for particular species or stocks.58/ Moreover, District Judge Charles Richey's emphasis in that case that "[t]he interests of the marine mammals come first" suggests that when determinations of OSP are in fact made, they should be supported by reliable and clearly demonstrable evidence.59/ b. Depletion No less puzzling than the Act's standard of optimum sustainable population is its provision for the determination of certain species or population stocks as "depleted." Nevertheless, such a determination has significant operational consequences. For example, public display permits may not be issued for any marine mammal determined to be depleted. Otherwise exempt taking by Alaskan natives may be regulated when a determination of depletion is made. Most significantly, 58/ 59/ 540 F.2d 1141 (D.C. Cir.), aff'g 414 F. Supp. 297 (D.D.C. The point made here is illustrated by Judge Richey's deci- for reasons to be discussed, the moratorium against taking cannot be waived while any marine mammal is depleted. Under the terms of the Act, a determination of depletion may be made if: the number of individuals within (B) has otherwise declined and (C) is below the optimum carrying capacity for the species or stock within its environment.60/ The ambiguity in the foregoing derives from the fact that the various criteria are stated in the disjunctive. That is, a species or population stock can be determined to be depleted if it meets any one of the three stated criteria. Thus, under criterion (C), a determination of depletion may be made if the number of individuals within a species or population stock is below the optimum carrying capacity of its environment. This criterion would be less ambiguous if its reference to optimum carrying capacity read "optimum sustainable population" instead. However, for the reasons previously described, it is submitted that the two terms mean the same thing, and therefore that a species or population must be determined to be depleted if its numbers are found to be below its OSP level.61/ 60/ 16 U.S.C. $1362 (1) (Supp. IV 1974). 61/ See text accompanying notes 46-51 supra. The criterion for depletion under discussion here was added by the Conference Committee without any explanation in its report. Even more vaguely worded is criterion (A), because the Act nowhere defines what constitutes a "significant" decline or over what period of years it is to be measured. Moreover, since each of the criteria for depletion is apparently independent of the others, it is possible to construe this criterion so as to allow a species to be declared depleted even if is numbers are above the optimum carrying capacity of its environment, so long as those numbers had declined significantly over a period of years. 62/ That interpretation, however, would be difficult to reconcile with the rest of the Act. Accordingly, a more plausible interpretation of this criterion would make it applicable where it is known that a given species or population stock has declined in numbers over a period of years, but the optimum carrying capacity of its habitat is not known. Criterion (B) likewise engenders major interpretational difficulties. When the Marine Mammal Protection Act was passed, the Endangered Species Act of 1973 did not yet exist. Accordingly, the original reference in criterion (B) was to the Endangered Species Conservation Act of 1969. That Act, however, provided protection only for those species that were "threatened with worldwide extinction."63/ Thus, what the Marine Mammal Protection Act did in 1972 was to create a category of species or populations which, though not yet in danger of extinction, might become so in the future. That was precisely the function of the category of 62/ There is no inherent contradiction in this hypothetical situation if one assumes that the relevant environment has deteriorated over time. 63/ See Chapter Twelve infra at text accompanying notes 19-23. "threatened" wildlife created a year later in the 1973 Act.64/ When the Endangered Species Act of 1973 was passed, its provision for protection of "threatened" species as well as "endangered" species would seem to have eliminated any need for retaining criterion (B). However, rather than eliminating that criterion, the 1973 Act merely replaced its reference to the 1969 Act with a reference to the 1973 Act. By virtue of that amendment, the Marine Mammal Protection Act now regards as "depleted" those species or population stocks which are neither endangered or threatened, but which might become so in the future. The anomaly of this scheme is that the protections afforded to "depleted" marine mammals are in certain respects even more stringent than the protections afforded to endangered species by the Endangered Species Act.65/ For example, whereas the latter Act authorizes the issuance of permits for taking endangered wildlife both for sci 64/ 65/ Id. at text accompanying notes 62-64. The legislative Where a species is determined to be both depleted and endan- See |