David Hayashi appeals his conviction of taking a marine mammal in violation of 16 U.S.C. Sec. 1372(a)(2)(A). We hold that the Marine Mammal Protection Act (MMPA) and the regulations implementing the act do not make it a crime to take reasonable steps to deter porpoises from eating fish or bait off a fisherman's line. Therefore, we conclude that insufficient evidence supported Hayashi's conviction, and we reverse.

* On the morning of January 24, 1991, Hayashi, a part-time commercial fisherman, and his son were fishing for Ahi off the coast of Waianae, Hawaii. A group of four porpoises began to eat the tuna off Hayashi's and his son's lines. Hoping the impact of the bullets hitting the water would scare the porpoises away from their catch, Hayashi fired two rifle shots into the water behind the porpoises. The shots did not hit the porpoises. When the Hayashis reeled in their lines, they discovered that a porpoise had in fact eaten a part of at least one of the tuna.

A state enforcement officer reported to the National Marine Fisheries Service (NMFS) that occupants of Hayashi's vessel had fired at dolphins. In February 1991, NMFS agents interviewed Hayashi and his son, taking written statements from each. An April 22, 1991 information charged Hayashi with knowingly taking a marine mammal in violation of the MMPA, 16 U.S.C. Sec. 1372(a)(2)(A).

The parties consented to proceed before a magistrate judge. In July 1991, after denying Hayashi's motion to dismiss the information for unconstitutional vagueness, the magistrate judge tried and convicted Hayashi on stipulated facts. The submitted facts consisted of the Hayashis' statements, and an NMFS agent's report and notes on the interviews of the father and son. Hayashi appealed to the district court, renewing his vagueness argument and raising a claim of insufficient evidence. In December 1991, without oral argument, the district court affirmed the conviction by written order. Hayashi appeals on grounds of unconstitutional vagueness and insufficiency of the evidence. We agree that his conviction must be reversed.1

The MMPA declares it unlawful for any person to "take" a marine mammal in United States waters. See 16 U.S.C. Sec. 1372(a)(2)(A). "The term 'take' means to harass, hunt, capture, or kill, or attempt to harass, hunt, capture, or kill any marine mammal." 16 U.S.C. Sec. 1362(13). The MMPA prescribes both civil and criminal penalties, but the latter apply only to persons who "knowingly" violate any provision of the act. See 16 U.S.C. Sec. 1375(b).

The government agrees that the only definition of "take" with possible application to Hayashi is "to harass" or "attempt to harass." The statute itself fails to define "harass." Various agencies of the federal government have promulgated regulations implementing the MMPA.2 The regulations applicable to porpoises, issued by the NMFS, do not define "harass" but further define "take" as including:The collection of dead animals, or parts thereof; the restraint or detention of a marine mammal, no matter how temporary; tagging a marine mammal; the negligent or intentional operation of an aircraft or vessel, or the doing of any other negligent or intentional act which results in disturbing or molesting a marine mammal; and feeding or attempting to feed a marine mammal in the wild.

50 C.F.R. Sec. 216.3.3 The "disturbing or molesting" example is the only regulatory definition potentially applicable to Hayashi's act of firing a rifle into the water behind a group of porpoises to scare them away from his fishing lines.4 We conclude that the regulation does not reach the conduct underlying Hayashi's conviction.

* Initially, we note that two substantial errors infected the proceedings before the magistrate judge and the district court. First, both parties, the magistrate judge, and the district court all employed the incorrect regulatory definition of the charged crime. Second, the district court's affirmance rested, in part, upon the erroneous belief that negligent acts are criminally punishable under the MMPA.

In opposing Hayashi's motion to dismiss, the government suggested using the definition of "harass" set forth in 50 C.F.R. Sec. 17.3, "an intentional or negligent act or omission which creates the likelihood of injury to wildlife by annoying it to such an extent as to significantly disrupt normal behavioral patterns which include ... breeding, feeding, or sheltering." At oral argument, the government did submit for the magistrate judge's consideration the regulatory definition in section 216.3. Nonetheless, in answering Hayashi's appeal to the district court, the government again argued that section 17.3 was the appropriately-controlling regulatory definition. Hayashi acquiesced in and promoted this view.5

As a result of the parties' briefing, both the magistrate judge at trial and the district court on appeal employed the regulatory definition in 50 C.F.R. Sec. 17.3, which does not define the crime with which Hayashi was charged.6 The regulation differs from the definition of "take" in 50 C.F.R. Sec. 216.3, particularly in the former's specific reference to disruption of "feeding." Section 17.3, issued by a different agency in a different federal department from the NMFS, implements an entirely separate statute, the Endangered Species Act.7 In effect, the district court entirely ignored the appropriate regulatory definition set out in section 216.3. Hayashi's conviction and its affirmance rest upon application of the wrong regulatory definition.8

Consistent with the MMPA criminal penalty scheme, the information charged Hayashi with "knowingly" taking a marine mammal. Under the MMPA, no criminal penalty can attach for negligent conduct. However, in referring the district court to the regulatory definition in section 17.3, which includes negligent acts, the parties failed to inform the court of this statutory requisite of "knowing" conduct for criminal liability to attach. Indeed, in briefing his appeal to the district court, Hayashi argued that the MMPA specifies no mens rea element. In answering Hayashi's brief, the government took no steps to draw the district court's attention to 16 U.S.C. Sec. 1375(b), and its explicit "knowledge" requirement.

Apparently unaware of this clear statutory command, the district court, relying upon 50 C.F.R. Sec. 17.3, concluded that a criminal violation of the MMPA could rest upon either negligent or intentional conduct.9 In addressing Hayashi's insufficiency claim, the district court held that, "[f]iring the rifle in waters containing porpoises was a negligent act that created a likelihood of injury to the porpoises." Although it went on to suggest that the evidence also showed an intentional attempt to stop the porpoises from eating, the district court's erroneous belief that negligence could support an MMPA criminal conviction tainted its consideration of Hayashi's appeal. Thus, Hayashi's conviction and its affirmance rested not only upon an incorrect regulatory definition, but also upon a misunderstanding of the required mens rea.

These errors affected the two most basic elements of every criminal proscription--the actus reus, or act itself, and the mens rea, or mental element required for criminal liability. The errors resulted not from a misunderstanding of obscure interpretive gloss, but from a basic misreading of clear statutory and regulatory commands. Although every lawyer involved was complicit in these errors, the responsibility for prosecuting the correct crime lies ultimately with the government.10

Under our precedent, if this case had been tried to a jury with instructions similarly incorrect as to both the definition of the crime and its mens rea, we would not hesitate to reverse. See, e.g., United States v. Washington, 819 F.2d 221, 226 (9th Cir.1987) ("ambiguous and equivocal" instructions on "basic issue" of level of intent is reversible error); United States v. Combs, 762 F.2d 1343, 1346 (9th Cir.1985) (instruction broadening possible basis for conviction "was so lacking in explanation of the offense charged and its elements that it was fundamentally erroneous and inadequate").11

Here, we need not determine whether a similar result should obtain in a case tried to a magistrate judge rather than to a jury. Hayashi was tried on stipulated facts; the magistrate judge was not required to resolve any factual disputes or to weigh the credibility of witnesses. We have a clear factual record from which to review Hayashi's conviction, and can do so without further perpetuating the fundamental errors described above. Therefore, cognizant of, but not hindered by, the elemental mistakes that pervaded Hayashi's trial and district court appeal, we consider whether there was sufficient evidence to convict Hayashi of the "knowing taking" of a marine mammal in violation of the MMPA.

As noted above, the government contends that Hayashi committed a criminal "taking" by "harassing" the porpoises; "harass" is left undefined by the statute. See 16 U.S.C. Sec. 1362(13). If we look to the administrative regulations, the only form of "taking" specified in 50 C.F.R. Sec. 216.3 that is potentially applicable to Hayashi's act of firing into the water behind the porpoises to divert them from his fishing lines is the prohibition of any "intentional act which results in disturbing or molesting a marine mammal." However, "disturb" and "molest" are not much more definitive than "harass." All three are very general terms, requiring us to resort to their context to ascertain their meaning.

Following the "familiar principle of statutory construction that words grouped in a list should be given related meaning," we look to the other statutory and regulatory examples of "taking." Third Nat'l Bank in Nashville v. Impac Ltd., 432 U.S. 312, 322, 97 S. Ct. 2307, 2313, 53 L. Ed. 2d 368 (1977). The statute groups "harass" with "hunt," "capture," and "kill" as forms of prohibited "taking." The latter three each involve direct, sustained, and significant intrusions upon the normal, life-sustaining activities of a marine mammal; killing is a direct and permanent intrusion, while hunting and capturing cause significant disruptions of a marine mammal's natural state. Consistent with these other terms, "harassment," to constitute a "taking" under the MMPA, must entail a similar level of direct and sustained intrusion.

Interpreting "harassment" under the MMPA to involve a sustained, direct, and significant intrusion also comports with a common understanding of the term "take," of which "harass" is simply one form. To "take" a marine mammal strongly suggests a serious and sustained diversion of the mammal from its natural routine. Congressional concern in passing the MMPA about marine mammals "in danger of extinction or depletion as a result of man's activities" supports this conception of "take." MMPA Sec. 2(1), Pub.L. No. 92-522, 86 Stat. 1027 (1972) (findings and declaration of policy).12 Killing, capturing, and hunting fit the common understanding of the term. "Harassment" under the MMPA, to constitute a "taking," must entail a similarly significant level of intrusiveness.

The NMFS regulatory definition of "take," as applied to porpoises, also supports this interpretation. See 50 C.F.R. Sec. 216.3. The detention and the tagging of a porpoise are each direct and significant intrusions upon the mammal's ordinary activities. The collection of dead mammals also involves an extended and direct intrusion upon the porpoise in the wild; "collection" suggests sustained activity to locate--or even to facilitate the demise of--deceased or dying marine mammals. The basic purpose of the "collection" prohibition is undoubtedly to deter difficult-to-detect killings of mammals by prohibiting possession of dead mammal by-products. In the context of these other examples, "molesting or disturbing" in 50 C.F.R. Sec. 216.3 must refer to sustained and severe disruptions of a porpoise's natural behavior.

The case for our interpretation is even stronger if we refer to 50 C.F.R. Sec. 17.3, the regulatory definition of "harass" urged by the government and upon which the district court exclusively relied. As discussed above, section 17.3, issued under the Endangered Species Act, is not the controlling regulatory definition and is an improper starting point for any MMPA prosecution; it is nonetheless analogous authority that is of considerable assistance in interpreting 50 C.F.R. Sec. 216.3.13 Section 17.3 specifically requires significant disruption of "normal" behavioral patterns. Deterrence of abnormal marine mammal activity is not proscribed.

This emphasis upon protecting natural animal behavior comports with the MMPA emphasis upon marine mammals as essential components of the natural marine ecosystem. See MMPA Sec. 2(2), Pub.L. 92-522, 86 Stat. 1027 (1972) (marine mammals "should not be permitted to diminish beyond the point at which they cease to be a significant functioning element in the ecosystem of which they are a part"). The concern that underlies the prohibition against disturbing mammals was for mammals as a part of nature, not for mammals acting in ways that endanger human life or property.

Interpreting the act and regulations otherwise, as prohibiting isolated interference with abnormal marine mammal activity, would lead to absurdity. Under such a broad interpretation, anyone who acted to prevent or in any way interfered with any marine mammal activity would face potential criminal prosecution. Nothing could legally be done to save a modern-day Jonah from the devouring whale, or to deter a rampaging polar bear from mauling a child. Neither could a porpoise intent on swimming into severely contaminated waters, or into the propellers of a motorized boat, be diverted by the selfless actions of a good Samaritan. These are but examples of what the unreasonably broad interpretation advocated by the government would lead us to. Our conclusion that only sustained and serious disruptions of normal mammal behavior fall under the term "harass" comports with a more reasonable understanding of the extent and scope of the MMPA.14

Applying our interpretation to the act for which Hayashi was convicted, we conclude that there was insufficient evidence to find a criminal "taking" by "harassment." The stipulated facts, consisting almost entirely of Hayashi's and his son's statements to the NMFS investigator, show that Hayashi did not fire at the porpoises, nor did he hit them. He simply fired two successive shots behind and outside the area of the porpoises to discourage them from eating bait and hooked tuna from his fishing lines--an act that is not a part of the porpoise's normal eating habits. Even if the shots succeeded in scaring away the porpoises--and the stipulated facts do not tell us whether the porpoises were aware of, or reacted to, the shots--any diversion from eating off the fisherman's lines is not of the significance or sustained effect required for a "taking" under the MMPA. Hayashi's conduct was not the kind of direct, sustained disruption of a porpoise's customary pursuits required to find a criminal "taking." Reasonable acts to deter porpoises from eating fish or bait off a fisherman's line are not criminal under the MMPA.15

Our conclusion that the MMPA and the regulations implementing the act do not reach Hayashi's act finds further and more specific support in the most recent NMFS amendment of the regulatory definition of "take." Effective April 19, 1991, the NMFS added "feeding or attempting to feed" to section 216.3 as an example of "harassment" under the MMPA. See 56 Fed.Reg. 11,693 (1991) (final rule); 55 Fed.Reg. 35, 328 (1990) (proposed rule) ("feeding activities may alter the behavior of marine mammals in such a way that they constitute harassment"). One concern motivating the regulatory amendment was the belief that human feeding of marine mammals, primarily dolphins and porpoises, led to potentially dangerous modification of normal feeding behavior. See 56 Fed.Reg. at 11,696 ("feeding ... is harmful because it disrupts their natural behavior and normal feeding patterns").

In this regard, the NMFS specifically noted that "the dead fish offered to the animals might condition them to seek other dead fish such as those found on baited hooks or in fish nets." Id. The Marine Mammal Commission, in commenting favorably upon the proposed rule, noted that feeding may condition animals to approach watercraft "where there is an increased likelihood that they will become entangled in fishing gear, be struck by vessels, or be shot, poisoned, or fed foreign objects." Id. at 11,695.

Thus, the regulatory amendment proscribing "feeding" was intended, in the long run, to deter precisely the kind of porpoise behavior that Hayashi witnessed and attempted himself to deter, in the short run, by firing the rifle into the water. It would make little sense for the MMPA to prohibit reasonable private measures to discourage the type of animal behavior that the NMFS has specifically identified as detrimental to marine mammals. The most recent NMFS modification of the regulatory definition of "take" supports our interpretation of the MMPA as not reaching Hayashi's conduct.

Finally, we note the quandary potentially created for one in Hayashi's position were we not to hold that the MMPA allows reasonable steps--those not resulting in sustained and severe disruption of the mammal's life activities--to deter porpoises from feeding on bait and hooked fish. Allowing porpoises to feed on bait might well run afoul of the "feeding" prohibition in section 216.3 and bring the fisherman to the attention of the vigilant enforcers of our criminal laws.16 If reasonable steps to divert porpoises from a fishing line were prohibited, the fisherman would face an impossible conundrum. Guilty of "harassment" by "feeding" if he did nothing, and guilty of "harassment" by "disturbing" if he took steps to prevent the feeding, our hypothetical Hayashi would face possible criminal prosecution under the MMPA no matter which course he chose. We do not believe that Congress or the NMFS intended to create such a "fisherman's dilemma."

We hold that reasonable actions--those not resulting in severe, sustained disruption of the mammal's normal routine--to deter porpoises from eating fish or bait off a fishing line are not rendered criminal by the MMPA or its regulations. Because the evidence shows that Hayashi's action was reasonable, we conclude that insufficient evidence supported his conviction. We reverse.

REVERSED.

JAMES R. BROWNING, Circuit Judge, dissenting.

The majority unjustifiably restricts the breadth of the Marine Mammal Protection Act to avoid subjecting Hayashi to a criminal prosecution the majority regards as unreasonable. The gloss imposed by the majority to limit the scope of "taking," a key jurisdictional term in the Act, has no source in the language, structure or legislative history of the Act and derives little support from the various circumstances collected to sustain it. It ignores the structure and purpose of the Act and substantially weakens it as an instrument for effectuating the public policy determined by Congress.

* Much more is at stake in defining the statutory term "taking" than Hayashi's freedom to fire his rifle at dolphins to protect a tuna caught by his son. The meaning assigned to this term defines the authority of the Secretary of Interior and the Secretary of Commerce to regulate private and public activities affecting marine mammals.1 The authority granted the Secretary by the Act to prohibit acts harmful to marine mammals and to develop and encourage means of ensuring their survival is keyed directly or indirectly to the concept of "taking." A cramped construction of the term "taking" will therefore restrict most aspects of the scheme envisioned by Congress for the protection of marine mammals, from the monitoring of marine mammal populations to research into more humane fishing techniques.

The references in the Act to the term "taking" confirm its importance. The substantive provisions of the Act open with a moratorium on the "taking and importation of marine mammals and marine mammal products." 16 U.S.C. Sec. 1371(a). The Secretary is authorized to allow exceptions to the moratorium by issuing permits "for taking and importation" of marine mammals, as detailed in the Act. 16 U.S.C. Secs. 1371, 1374. What is prohibited and what is permitted are stated in terms of "taking" and will be fixed by the definition of that term. 16 U.S.C. Secs. 1372, 1375, 1376. The Secretary's regulatory judgments are to be based upon the past and projected impact of "taking" upon the well-being of the species or stocks and the purposes and policies of the Act. 16 U.S.C. Sec. 1373(a). The Act requires the Secretary to fund research into methods of fishing that minimize the incidental "taking" of marine mammals. 16 U.S.C. Secs. 1380, 1381. Vessels receiving exemptions are required to report incidental "taking" of marine mammals, to provide information useful in the study of the effect of certain fishing techniques on marine mammal populations. 16 U.S.C. Sec. 1383a(c), (g). The Act establishes a Marine Mammal Commission, one of whose duties is to conduct a "continuing review ... of humane means of taking marine mammals." 16 U.S.C. Sec. 1402(a)(2).

The scheme of the Act is to define "taking" broadly, thus giving ample scope to the regulatory scheme, and at the same time, to introduce the flexibility that is essential to the effective administration of the Act by authorizing the Secretary to approve particular conduct that would otherwise be prohibited although consistent with the purposes of the Act and required by changing circumstances. The statutory language, the legislative history, the Secretary's regulations, and the type of conduct approved by the Secretary in the past all point to an interpretation of the jurisdictional term "taking" sufficiently broad to encompass Hayashi's act of deliberately firing his rifle near feeding dolphins to frighten them off.

" 'Take' is defined broadly by the Act...." H.Rep. No. 707, 92nd Cong., 1st Sess. (1971), reprinted in 1972 U.S.C.C.A.N. 4144, 4155; see also 118 Cong.Rec. 34,639 (Oct. 10, 1972) (comments of Representative Dingell, Committee Chairman and floor manager of the bill). The Act defines "take" as meaning "to harass, hunt, capture, or kill," or attempt to do so. See 16 U.S.C. Sec. 1362(13). Congress did not limit the coverage of the statute to the physical destruction or injury of marine mammals. Rather, it sought to regulate a wide variety of human activity potentially harmful to such animals, progressing in severity from "harass" to "hunt," "capture," and finally "kill." 1972 U.S.C.C.A.N. at 4147-48.

Congress found these activities had threatened the survival of marine mammals, although in ways not fully known. As the Committee on Merchant Marine and Fisheries concluded, in these circumstances,it seems elementary common sense to the Committee that legislation should be adopted to require that we act conservatively--that no steps should be taken regarding these animals that might prove to be adverse or even irreversible in their effects until more is known. As far as could be done, we have endeavored to build such a conservative bias into the legislation here presented.

Id. at 4148. Congress's goal was nothing less than "the optimum protection of the marine mammals affected by the bill." Id. (emphasis added).

The term "harass" performs the specific function of broadening the definition of "taking" and therefore the Act itself. The House Report highlights the role of "harass" in enlarging the scope of the Act: "The definition of taking ... includes the concept of harassment, and it is intended that this term be construed sufficiently broadly to allow the regulation of excessive or wanton use of ... chemical compounds, as well as the operation of powerboats." Id. at 4150. See also id. at 4155; 118 Cong.Rec. 34,639 (Oct. 10, 1972). The Commerce Department objected that the proposed definition of "taking" was overly broad and proposed an alternative that omitted the term "harassment."2 Congress rejected the proposal. 1972 U.S.C.C.A.N. at 4166-67, 4170. When the Act was amended in 1988, Congress again emphasized that "[t]aking of marine mammals, as defined in the Act, is not limited to capturing or killing them, but includes harassment of the mammals as well."3 H.Rep. No. 970, 100th Cong., 2nd Sess. (1988), reprinted in 1988 U.S.C.C.A.N. 6154, 6158.

Examples of "taking" identified in the legislative history and regulations support a sufficiently broad reading of the term to encompass Hayashi's conduct. Congress identified the "intentional pursuit [of marine mammals] or use of acoustic deterrence devices" as examples of harassment falling within the Act's prohibition. 1988 U.S.C.C.A.N. at 6164. The regulatory explanation of "taking" identifies conduct that is only moderately intrusive and includes the significant catch-all "any other negligent or intentional act which results in disturbing or molesting a marine mammal." See 50 C.F.R. Sec. 216.3.4

The broad scope of "taking" is also reflected in permits routinely issued to authorize conduct no more intrusive than Hayashi's conduct, which in the view of the agency and the applicant nonetheless constitutes "harassment" prohibited under the Act. Permits have been issued identifying as "harassment" but nonetheless authorizing "vessel approach, helicopter photogrammetry and photographic identification," 58 Fed.Reg. 41458 (Aug. 4, 1993); see also 58 Fed.Reg. 37716 (July 13, 1993); 58 Fed.Reg. 27270 (May 7, 1993); the broadcast of "underwater acoustic recordings," 57 Fed.Reg. 26649 (June 15, 1992); see also 58 Fed.Reg. 7548 (Feb. 8, 1993); and the incidental effects of intrusive studies of marine mammals, 58 Fed.Reg. 29199 (May 19, 1993); see also 58 Fed.Reg. 14202 (Mar. 16, 1993).

The examples listed in 50 C.F.R. Sec. 216.3 argue against rather than in favor of the majority's limitation of "taking" to "direct, sustained and significant intrusions upon the natural, life-sustaining activities of a marine mammal." (Opinion p. 1282) Under the regulation, a "restraint or detention," "no matter how temporary," qualifies as a "taking," but the majority's proposed standard requires a "sustained intrusion." "Collection of dead animals" does not support the majority's requirement of "sustained intrusion on life-sustaining activities." "Tagging a marine mammal" cannot be considered a "significant intrusion on the normal, life-sustaining activities of a marine mammal"; it is a humane means of tracking animals for research, requiring only a minimal intrusion on their activities, life-sustaining or otherwise.5

The majority concludes that only disruptions of "normal mammal behavior" are contemplated by the term "harass" and characterizes the porpoises' behavior in this case as "unnatural" or "abnormal marine mammal activity." (Opinion p. 1283) This addition to the definition of the scope of the Act will require courts and regulators to develop a workable system of rules around the elusive concept of "normal marine mammal behavior," a term not mentioned in the Act or its legislative history. Moreover, the porpoises who stole the fish from Hayashi's line were not behaving unnaturally or abnormally. They were merely competing with Hayashi for the same catch. By excluding such behavior from the protection of the Act, the majority frustrates one of the primary purposes of the Act--the protection of marine mammals from harm arising out of human fishing activity.6 See 1972 U.S.C.C.A.N. at 4148 (discussing the harm caused to porpoises by commercial tuna fishing techniques).

Congress included a system of exceptions and exemptions in the Act to enable the Secretary to administer effectively the Act's broad prohibition of activity that might prove harmful to marine mammals. These provisions grant the Secretary the necessary authority to achieve the overall objective of protecting marine mammals while affording reasonable protection to other interests. The statutory structure and the manner in which the Secretary has administered it offer additional, significant support for a broad reading of the jurisdictional term "taking," and specifically for application of the Act to the conduct involved in this case.

The Act bars all taking of marine mammals with specified exceptions. 16 U.S.C. Sec. 1371(a). Among other exceptions, "[m]arine mammals may be taken incidentally in the course of commercial fishing operations" under permits issued by the Secretary and subject to conditions specified in the statute.7 16 U.S.C. Sec. 1371(a)(2). The Secretary is authorized to waive the general bar against "taking" of marine mammals, and adopt "suitable regulations, issue permits, and make determinations" governing "taking" that are "in accord with sound principles of resource protection and conservation." 16 U.S.C. Sec. 1371(a)(3)(A). See also 16 U.S.C. Sec. 1374(a) (authorizing the Secretary to "issue permits which authorize the taking or importation of any marine mammal" subject to specific conditions and in accordance with stipulated procedures).8

In the exercise of these powers, the Secretary has from time to time issued regulations dealing with the general problem presented by the facts of this case. A regulation issued in 1980 authorized commercial fishermen in specified categories to "take such steps as are necessary to protect [their] catch" from marine mammals. 50 C.F.R. Sec. 216.24(d)(5)(ii). In 1988, Congress added an exemption to the Act under which commercial fishermen in certain fisheries who registered with the Secretary would be exempt from the statutory prohibition against incidental taking of marine mammals until October 1, 1993. See 16 U.S.C. Sec. 1383a. The Secretary adopted regulations pursuant to the 1988 exemption permitting such fishermen to "intentionally take marine mammals to protect catch, gear, or person during the course of commercial fishing operations," upon securing an exemption certificate or complying with reporting requirements.9 50 C.F.R. Secs. 229.4(a), 229.6(c)(5), 229.7(d) (emphasis added).

The record indicates that Hayashi was a commercial fisherman and held the necessary certificate, and that the conduct underlying his conviction occurred during the period to which the regulations enforcing the 1988 exemption applied. Hayashi did not claim his activities fell within the exemption, however, and the record does not permit a determination of that question. Nonetheless, the existence and substance of the statutory and regulatory exception are significant.

The regulations enforcing the 1988 exemption contradict the majority's conclusion that the Act prohibits only direct and sustained intrusions on a marine mammal's life-sustaining activities. The authorization to "take" marine mammals to protect a fisherman's catch is expressly limited to conduct "not expected to cause death or injury to a marine mammal."10 50 C.F.R. Secs. 229.6(c)(5), 229.7(d). This limitation makes it clear conduct necessary to protect a catch and not expected to threaten the life of a porpoise was nonetheless included within the statute's prohibition against "taking."

Equally important, the 1988 exemption illustrates an essential element of the structure of the Act which the majority ignores--the use of the Secretary's power to authorize controlled exceptions in appropriate circumstances and under proper conditions to the statute's broad prohibition of conduct potentially harmful to marine mammals, without irreversibly limiting the application of the Act to such conduct in other circumstances and under other conditions. With its approval of Hayashi's conduct, the majority not only limits the scope of the Act, but also the ability of the Secretary to protect marine mammals while accommodating the needs of commercial fishermen.