The opinion of the court was delivered by: Colleen Kollar-kotelly United States District Judge
Plaintiff, WildEarth Guardians, has brought suit against Defendant, Ken Salazar, Secretary of the Interior (the "Secretary"),*fn1 challenging the denial of two petitions submitted by Plaintiff, each of which sought increased federal protection for the Utah prairie dog. Presently before the Court is Plaintiff's  Motion to Supplement the Administrative Record, which is opposed by Defendant. Although the parties indicate that they have successfully resolved most of Plaintiff's concerns regarding the administrative record without the need for Court intervention, a dispute remains as to one document: the Utah Division of Wildlife Resources' 1979 petition to remove the Utah prairie dog from the list of threatened and endangered species (hereinafter, the "1979 Petition"). After thoroughly reviewing the parties' submissions, including the attachments thereto, applicable case law, statutory authority, and the record of the case as a whole, the Court shall DENY Plaintiff's  Motion to Supplement the Administrative Record, for the reasons set forth below.
Although the merits of Plaintiff's challenge to the Secretary's decisions are not currently before the Court, it is helpful to understand the relevant statutory and regulatory background underlying Plaintiff's claims in this case in order to place the parties' arguments with respect to the pending Motion to Supplement in the proper context. Accordingly, the Court shall first briefly review the relevant provisions of the Endangered Species Act ("ESA"), 16 U.S.C. §§ 1531 et seq., and its enacting regulations, before then turning to the procedural and factual background of the case at hand.
A. Statutory and Regulatory Background
In 1973, Congress enacted the ESA "to provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved, [and] to provide a program for the conservation of such endangered species and threatened species."*fn2 16 U.S.C.§ 1531(b). In order to receive the Act's protections, a species must be "listed" as endangered or threatened by the Secretary of the Interior.*fn3 The determination of whether a given species should be listed as endangered or threatened under the ESA may be made either on the initiative of the Secretary via the "candidate process" or in response to a citizen's request via the "petition process." See id. §§ 1533(a)(1), 1533(b)(3). Once a species is listed, through either the candidate process or the petition process, the ESA provides that the Secretary "shall issue such regulations as he deems necessary and advisable to provide for the conservation of such species." Id. § 1533(d).
As is relevant to the instant case, any "interested person" may petition to have a species listed as threatened or endangered pursuant to the petition process referenced above. Id. § 1533(b)(3)(A). Once a petition is received, the Secretary is required to determine whether the petition presents "substantial scientific or commercial information" indicating that the petitioned action may be warranted. Id. By regulation, the term "substantial information" is defined as "that amount of information that would lead a reasonable person to believe that the measure proposed in the petition may be warranted." 50 C.F.R. § 424.14(b)(1). The ESA specifies that the Secretary is required to make that finding - known as the "90-day finding" - within 90 days after receiving the petition, "[t]o the maximum extent practicable." Id. The 90-day finding is published in the Federal Register. Id. § 1533(b)(3)(A). If the Secretary determines that the listing is not warranted, the listing process for that species is terminated. See id. However, if the Secretary determines that the petitioned action is warranted, the Act provides that the "Secretary shall promptly commence a review of the status of the species concerned." Id. Within 12 months of the receipt of the petition, the Secretary is required to make a finding-known as the "12-month finding"-stating whether the petitioned action is (a) warranted; (b) not warranted; or (c) warranted but precluded by other listing activity. Id. § 1533(b)(3)(B).
B. Procedural and Factual Background
As discussed above, Plaintiff's lawsuit challenges two separate 90-day findings issued by the Secretary denying petitions submitted by Plaintiff. Only one of those negative 90-day findings, however, is currently at issue in Plaintiff's Motion to Supplement. Specifically, Plaintiff's motion seeks supplementation of the administrative record submitted by the Secretary with respect to the negative 90-day finding issued on February 21, 2007, in which the Secretary denied Plaintiff's February 3, 2003 petition requesting the Utah prairie dog be uplisted from threatened to endangered (hereinafter, "2003 Petition"). See Pl.'s Mem. in Support of its Mot. to Supplement, Docket No. [23-2], hereinafter ("Pl.'s Mem."), at 3, n. 3; see also Am. Compl., ¶¶ 34, 38. Accordingly, in reviewing the relevant factual and procedural background, the Court focuses exclusively on the 2003 Petition.
As set forth in Plaintiff's Amended Complaint, the Utah prairie dog was originally listed as an endangered species in 1973. Id. ¶ 30. On November 5, 1979, the Utah Division of Wildlife Resources submitted the above-referenced 1979 Petition requesting the Secretary delist the Utah prairie dog. Id. The 1979 Petition triggered a lengthy administrative review process that culminated in the Secretary's decision on May 29, 1984, to downlist the Utah prairie dog to a threatened species. Id. Plaintiff's 2003 Petition requested the Secretary return the Utah prairie dog to the endangered category. Id. ¶ 34. On February 21, 2007, the Secretary issued a negative 90-day finding denying the 2003 Petition and concluding that the petition did not provide substantial scientific or commercial information indicating that reclassification of the Utah prairie dog from threatened to endangered status might be warranted. Id. ¶ 38.
Plaintiff filed the instant lawsuit on September 16, 2008, challenging, inter alia, the Secretary's negative 90-day finding with respect to the 2003 Petition. See Compl., Docket No. . Pursuant to the Court's  Scheduling and Procedures Order, the Secretary subsequently filed the administrative record with respect to the 2003 Petition and the Secretary's February 21, 2007 negative 90-day finding (hereinafter, the "Administrative Record"). See Not. of Lodging of Admin. Record, Docket No. ; Admin. Record, Docket No. . Ms. Laura Romin, Assistant Field Supervisor of the Utah Ecological Services Field Office within FWS, certified that she had compiled the documents and index that make up the relevant Administrative Record and that the documents provided therein "comprise the full and complete administrative record for the U.S. Fish and Wildlife Service's decision on the plaintiff's petition to uplist the Utah prairie dog from threatened to endangered status under the Endangered Species Act." See Not. of Lodging of Admin. Record, Ex. 1 (Declaration of Laura Romin Certifying Administrative Record).
The parties subsequently met and conferred regarding Plaintiff's concerns with the Administrative Record. See Pl.'s Mem. 2-3. Although the parties were able to resolve most of Plaintiff's concerns, a dispute remains as to whether the 1979 Petition is properly considered a part of the Administrative Record. See id. Unable to resolve this issue, Plaintiff filed the now-pending  Motion to Supplement the Administrative Record, in which Plaintiff contends that the Administrative Record filed by the Secretary is incomplete due to the omission of the 1979 Petition. Plaintiff therefore seeks an order requiring the Secretary to supplement the Administrative Record with that petition. See generally Pl.'s Mot.; Pl.'s Reply, Docket No. . The Secretary opposes Plaintiff's request, arguing that he did not consider, either directly or indirectly, the 1979 Petition in evaluating the 2003 Petition, such that the petition should not be included in the Administrative Record. See Def.'s Opp'n, Docket No. . As the briefing on Plaintiff's Motion to Supplement is now complete, the issue is ripe for the Court's resolution and review.
Judicial review of agency action under the ESA is governed by the APA, which requires in relevant part that a court set aside agency action that is "arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law." Cabinet Mountains Wilderness v. Peterson, 685 F.2d 678, 685 (D.C. Cir. 1982) ("Since the ESA does not specify a standard of review, judicial review is governed by section 706 of the Administrative Procedure Act."); see also 5 U.S.C. § 706(2)(A). In undertaking its review of the agency decision, the APA directs a court to "review the whole record or those parts of it cited by a party." 5. U.S.C. § 706. This requires the Court to review "the full administrative record that was before the Secretary at the time he made his decision." Citizens to Preserve Overton Park v. Volpe, 401 U.S. 402, 420 (1971), abrogated on other grounds by Califano v. Sanders, 430 U.S. 99 (1977). Courts in this Circuit have "interpreted the 'whole record' to include 'all documents and materials that the agency 'directly or indirectly considered' . . . [and nothing] more nor less.'" Pac. Shores Subdivision, Cal. Water Dist. v. U.S. ...