[Code of Federal Regulations]
[Title 50, Volume 7]
[Revised as of January 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 50CFR424.17]

[Page 857-858]
 
                    TITLE 50--WILDLIFE AND FISHERIES
 
CHAPTER IV--JOINT REGULATIONS (UNITED STATES FISH AND WILDLIFE SERVICE, 
 
PART 424_LISTING ENDANGERED AND THREATENED SPECIES AND DESIGNATING
 
                     Subpart B_Revision of the Lists
 
Sec. 424.17  Time limits and required actions.

    (a) General. (1) Within 1 year of the publication of a rule 
proposing to determine whether a species is an endangered or threatened 
species, or to designate or revise critical habitat, the Secretary shall 
publish one of the following in the Federal Register:
    (i) A final rule to implement such determination or revision,
    (ii) A finding that such revision should not be made,
    (iii) A notice withdrawing the proposed rule upon a finding that 
available evidence does not justify the action proposed by the rule, or
    (iv) A notice extending such 1-year period by an additional period 
of not more than 6 months because there is substantial disagreement 
among scientists knowledgeable about the species concerned regarding the 
sufficiency or accuracy of the available

[[Page 858]]

data relevant to the determination or revision concerned.
    (2) If an extension is made under paragraph (a)(1)(iv) of this 
section, the Secretary shall, within the extended period, take one of 
the actions described in paragraphs (a)(1) (i), (ii), or (iii) of this 
section.
    (3) If a proposed rule is withdrawn under paragraph (a)(1)(iii) of 
this section, the notice of withdrawal shall set forth the basis upon 
which the proposed rule has been found not to be supported by available 
evidence. The Secretary shall not again propose a rule withdrawn under 
such provision except on the basis of sufficient new information that 
warrants a reproposal.
    (b) Critical habitat designations. A final rule designating critical 
habitat of an endangered or a threatened species shall to the extent 
permissible under Sec. 424.12 be published concurrently with the final 
rule listing such species, unless the Secretary deems that--
    (1) It is essential to the conservation of such species that it be 
listed promptly; or
    (2) Critical habitat of such species is not then determinable,

in which case, the Secretary, with respect to the proposed regulation to 
designate such habitat, may extend the 1-year period specified in 
paragraph (a) of this section by not more than one additional year. Not 
later than the close of such additional year the Secretary must publish 
a final regulation, based on such data as may be available at that time, 
designating, to the maximum extent prudent, such habitat.