xviii Preface
decline of populations of many species of plants and animals is
driven by the uncontrolled expansion of human populations,
which have quadrupled in the past century. In 1950, 2.5 bil-
lion people inhabited the Earth; today there are about 7 billion
people, and a conservative estimate predicts that the human
population will grow to 9 billion by 2045.
Scientists, naturalists, and environmentalists believe exten-
sive eff orts are required to prevent further extinctions of plants
and animals. Th ey consider the Endangered Species Act (ESA),
passed in 1973 and signed by Republican Richard Nixon, the
best line of defense to prevent species extinctions and diversity
loss in the United States. Under the ESA, there has been steady
progress in species recovery as measured by prevention of ex-
tinctions and the large number of threatened and endangered
species recovering on the schedule set by the U.S. Fish and
Wildlife Service. Scientists know that recovery of endangered
species is a complicated process because at-risk species often
have very small populations and inhabit areas of limited habi-
tat. Recovery, therefore, can be a long process that may take
decades.
Th e ESA has critics who wish to weaken it. Some private
property owners, conservative politicians, the fossil fuel in-
dustry, developers, and representatives of commercial interests
claim the ESA is not working, and they resent the regulations
imposed by the act and claim too much interference by the
federal government in private property decisions. As measured
by the number of species declared recovered and delisted, they
deem the act ineff ective. Th ere is concern about eff ects on
property rights and the cost to industry and jobs.
Th e debate over the ESA and its eff ectiveness has been
brewing for a long time and may be reaching a climax. Envi-
ronmental skepticism is high in the Trump administration as
demonstrated by appointments to the cabinet of avowed cli-
mate change skeptics and a Congress consisting of the same
politicians who introduced dozens of amendments, bills, and
riders aimed at weakening and stripping away provisions of the
