Opinion for the Court filed by Circuit Judge RANDOLPH.
After winning a lawsuit against the Secretary of the Interior, Joyce M. Hill filed an application to recover her attorney’s fees and expenses under the Equal Access to Justice Act, 28 U.S.C. § 2412. The district court denied the application on the basis that the Secretary’s position at the *1005 merits stage was substantially justified. Hill appealed. We affirm.
I.
The mute swan, a bird indigenous to Eurasia, was introduced into the United States for ornamental purposes in the 19th and 20th centuries. Joyce Hill took up the cause of the mute swan in 1999. She sued nineteen federal, state and private defendants, complaining of numerous wrongs the mute swan species had allegedly suffered. Her principal claim was that the Secretary of the Interior improperly denied the species the protection of the Migratory Bird Treaty Act, 16 U.S.C. §§ 703-712. The Treaty Act limits
inter alia
the pursuit, hunting and killing of migratory birds covered by four treaties to which the United States is a party.
See Humane Society v. Glickman,
The district court held that the Secretary’s
List of Migratory Birds
rested on a permissible construction of the Treaty Act and granted the Secretary’s motion for summary judgment.
Hill v. Babbitt,
No. 99-CV-1926,
Hill’s winning claim turned on the meaning of a key statutory term — “migratory bird” — which the Treaty Act did not define at the time of Hill’s suit.
1
The Act stated only that its protections extend to “any migratory bird ... included in the terms of’ four bilateral treaties that the United States signed with Great Britain (on behalf of Canada), Mexico, Japan and the Soviet Union. 16 U.S.C. § 703(a). Each treaty defines the protected class of birds differently.
See Hill,
The
Hill
panel thought the relevant statutory and treaty language “strongly indicate[d]” that the mute swan is a protected migratory bird.
The court considered whether, despite the ostensibly plain text, the Secretary’s interpretation might be permissible. Id. at 105. The Secretary offered three main reasons for excluding the species: the mute swan is not native to the United States; the mute swan is harmful to other protected bird species and their environments; and extending protection to the mute swan might conflict with other statutory obligations. See id. As to the first two points, the court had “no idea whether these arguments are pertinent, and, if so, whether they are compelling” because the agency record was “barren” on those issues. Id. at 105. The court therefore held that the Secretary failed to justify her interpretation and vacated the list insofar as it excluded the mute swan. Id. at 107.
II.
With a merits victory secure, Hill petitioned the district court for an award of attorney’s fees pursuant to the Equal Access to Justice Act. The Act authorizes an award of fees to a party prevailing against the government unless the government establishes that its position was “substantially justified or ... special circumstances make an award unjust.” 28 U.S.C. § 2412(d)(1)(A). A position is substantially justified if the underlying agency action and the legal arguments in defense of the action had “a reasonable basis both in law and fact.”
Pierce v. Underwood,
The Secretary’s chief argument before the merits panel was that the Treaty Act did not apply to species of migratory birds that were not native to North America. The Secretary mustered ample evidence to support the factual assertion that the mute swan is an exotic species. According to the Secretary’s expert testimony and documentary evidence, all feral North American mute swans are descended from escaped and released members of ornamental groups introduced into the United States.
In support of her assertion that the Treaty Act does not apply to exotic species, the Secretary argued that the taxonomic listing of bird families in Article I of the Canada Treaty reveals a latent ambiguity in the otherwise unqualified term “migratory birds.” The treaty lists protected bird families, and each family name is followed by the common names of species and species groups in each family. See Canada Treaty, art. I, § 1(a); see also Protocol Amending the 1916 Convention for the Protection of Migratory Birds in Canada and the United States (“Canada Protocol”) art. I, § 1, U.S.-Can., Dec. 14, 1995, Sen. Treaty Doc. 104-28. According to the Secretary, each enumerated species and at least some members of each enumerated group were native to the signatory nations. By contrast, many nonnative species within each family were not listed. From that pattern, the Secretary argued, the Secretary reasonably understood the Canada Treaty to distinguish between na *1007 tive species and exotic species introduced to North America by man. The Secretary therefore believed it proper to limit the Treaty Act’s protections to swan species native to North America. 2
The Secretary further argued that reading the treaties to cover the mute swan would be a self-destructive interpretation. The mute swan is a beautiful bird but it can be nasty. The Secretary produced evidence that the species is a menace to other birds protected by federal law. A territorial aggressor and prolific procreator, the mute swan depletes native birds’ food sources and occupies their nesting grounds. The Acting Director of the U.S. Fish and Wildlife Service concluded that “mute swans pose a serious threat to the ecological integrity of many areas, including the National Wildlife Refuge System and other Federal Lands committed to the maintenance of natural wildlife diversity.”
The Secretary’s concern about the impact of destructive exotic species like the mute swan had some basis in three of the migratory bird treaties. Provisions in the treaty with Japan, the treaty with the former Soviet Union, and the Canada Protocol required the signatory countries to control the importation of live animals that may be harmful to migratory birds or their environments. See Convention for the Protection of Migratory Birds and Birds in Danger of Extinction, and Their Environment, art. VI, U.S.-Japan, Mar. 4, 1972, 25 U.S.T. 3331; Convention Concerning the Conservation of Migratory Birds and their Environment, art. IV § 2(b), U.S.U.S.S.R, Nov. 19, 1976, 29 U.S.T. 4649; Canada Protocol, art. IV. The Secretary also pointed out that some mute swans in North America were introduced only after the signing of the first migratory bird treaty in 1916. 3
Of course the Secretary’s position did not prevail. But the question is not whether the Secretary had the better arguments. It is enough that the Secretary’s interpretation and legal arguments had a reasonable basis in fact and in the text and purpose of the controlling statute and treaties. There was nothing unusual or unsound about the Secretary’s basic premise that an enactment’s context and underlying policies can cast doubt on “ ‘the most natural reading’ of a statutory phrase.”
Tataranowicz v. Sullivan,
That assessment is consistent with the merits panel’s reasoning.
See Taucher,
At the fee stage, however, an inadequate agency record is not necessarily fatal.
See F.J. Vollmer Co., Inc. v. Ma-gaw,
Nor can we fault the Secretary for thinking the court might accept counsel’s elaboration of the Secretary’s interpretation. At least until the Supreme Court’s decision in
United States v. Mead Corp.,
In sum, the thinness of the agency record at the merits stage does not alter our conclusion that the Secretary’s interpretation and arguments had a reasonable basis in fact and law. The district court did not abuse its discretion in so finding. 5
Affirmed.
Notes
. The
Hill
panel recounted the regulatory history.
See
. In response to this court’s decision in
Hill,
the Migratory Bird Treaty Reform Act amended the Migratory Bird Treaty Act to limit its scope “only to migratory bird species that are native to the United States or its territories.” Pub.L. No. 108-447, Div. E., Tide I, § 143(b), 118 Stat. 2809, 3071 (codified at 16 U.S.C. § 703(b)(1));
see also Fund for Animals v. Kempthorne,
. For example, the Secretary presented evidence that the entire mute swan population of the Chesapeake Bay — where Hill alleged aesthetic injury — descends from 5 ornamental swans that escaped from waterfront estates in 1962.
. The fee stage analysis focuses on the reasonableness of the government's position at the "time the government took this position.”
Trahan v. Brady,
. We also deny Hill’s request to increase her award of costs under Federal Rule of Civil Procedure 54(d) because she has not shown that the district court abused its discretion in calculating the costs.
