Document ID: ./input/supremecourt_opinions/opinions/18pdf/17-71_omjp.pdf
Page Number: 1.0

(Slip Opinion) 

OCTOBER  TERM,  2018 

1 

Syllabus 

NOTE:  Where  it  is  feasible,  a  syllabus  (headnote)  will  be  released,  as  is
being  done  in  connection  with  this  case,  at  the  time  the  opinion  is  issued.
The  syllabus  constitutes  no  part  of  the  opinion  of  the  Court  but  has  been
prepared  by  the  Reporter  of  Decisions  for  the  convenience  of  the  reader. 
See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337. 

SUPREME COURT OF THE UNITED STATES 

Syllabus 

WEYERHAEUSER CO. v. UNITED STATES FISH AND 
WILDLIFE SERVICE ET AL. 

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR 
THE FIFTH CIRCUIT 

No. 17–71.  Argued October 1, 2018—Decided November 27, 2018 

The Fish and Wildlife Service administers the Endangered Species Act
of  1973  on  behalf  of  the  Secretary  of  the Interior.    In  2001,  the  Ser-
vice  listed  the  dusky  gopher  frog  as  an  endangered  species.    See  16 
U. S. C. §1533(a)(1).  That required the Service to designate “critical 
habitat”  for  the  frog.  The  Service  proposed  designating  as  part  of
that critical habitat a site in St. Tammany Parish, Louisiana, which
the Service dubbed “Unit 1.”  The frog had once lived in Unit 1, but
the land had long been used as a commercial timber plantation, and
no  frogs  had  been  spotted  there  for  decades.    The  Service  concluded 
that Unit 1 met the statutory definition of unoccupied critical habitat 
because its rare, high-quality breeding ponds and distance from exist-
ing  frog  populations  made  it  essential  for  the  species’  conservation. 
§1532(5)(A)(ii).  The Service then commissioned a report on the prob-
able  economic  impact  of  its  proposed  critical-habitat  designation.
§1533(b)(2).  With regard to Unit 1, the report found that designation
might bar future development of the site, depriving the owners of up
to  $33.9  million.    The  Service  nonetheless  concluded  that  the  poten-
tial  costs  were  not  disproportionate  to  the  conservation  benefits  and 
proceeded to designate Unit 1 as critical habitat for the dusky gopher
frog.

Unit 1 is owned by petitioner Weyerhaeuser and a group of family
landowners.  The owners of Unit 1 sued, contending that the closed-
canopy  timber  plantation  on  Unit  1  could  not  be  critical  habitat  for
the  dusky gopher  frog,  which  lives in  open-canopy  forests.    The  Dis-
trict Court upheld the designation.  The landowners also challenged 
the  Service’s  decision  not  to  exclude  Unit  1  from  the  frog’s  critical
habitat, arguing that the Service had failed to adequately weigh the