BOOKS: Tracking the vanishing frogs

From ANIMAL PEOPLE, November 1995:

Tracking the vanishing frogs
by Kathryn Phillips
Penguin Books USA Inc. (375 Hudson
St., New York, NY 10014), 1994. 244
pages, paperback. $11.95.

Stanford University, of Palo Alto,
California, in late September gave up hope
of completing on schedule a new graduate
student housing complex near Lake
Lagunita, a usually dry mudflat where football
rallies were held almost every fall from
1897 to 1992. The student spirit committee
moved the rallies when someone found
California tiger salamanders, supposedly
extirpated from the region, trekking to the
remnants of the lake across a busy highway.
Stanford has now rescheduled construction
to avoid building the parking lot during the
three-month salamander migration season.

Stanford’s concern for amphibians
is rather unique––so much so that nearly half
the world’s known amphibian species,
including frogs, toads, newts, and salamanders,
went extinct or entered serious decline
during the 1980s before anyone recognized a
global pattern to the losses. Unique regional
circumstances often contributed. A cleared
tract of rainforest, cattle trampling a stream
bank, a vogue for eating frogs’ legs, or the
introduction of trout to a mountain lake all
have wiped out amphibian species overnight.
In the 1980s, however, many
amphibians were lost without any such obvious
direct threats. The golden frogs of Costa
Rica vanished from the middle of protected
habitat in 1987 without a previous sign that
they were in trouble. Trying to find out why,
researcher Martha Crump learned other
amphibian biologists around the world were
also mystified by inexplicable extinctions.
In 1990, at last, they joined together to
sound the alarm. Individually, most
amphibian species are ecologically unimportant.
Their loss hurts the food chain for
some predators, but other species generally
take over their habitat. Collectively, however,
the abrupt loss of so many members of
one of the oldest orders of life is a warning
of major ecological change.
Tracking The Vanishing Frogs,
focusing on California frogologists Mark
Jennings and Mark Hayes, is a nonfiction
murder mystery. Kathryn Phillips builds
suspense, drops clues, and gradually
reveals the killer much as it was revealed,
bit by bit, by science. Amphibians, it
seems, have low resistance to a particular
form of ultraviolet radiation. Thinning of
the ozone layer due to pollution has resulted
in more of this radiation striking the earth,
especially at higher elevations. Sitting in the
sunlight to warm themselves enough to
move away from danger, amphibians ironically
absorb deadly doses.
As Tracking The Vanishing Frogs
went to press, marine biologists discovered
that increased ultraviolet radiation is apparently
also responsible for drastic drops in the
amount of krill and plankton in the seas off
Antarctica and California. This in turn hurts
fish, sea birds, and marine mammals, especially
baleen whales. Nature often quickly
fills ecological voids, and oceans are exceptionally
stable ecosystems, so perhaps
strains of krill and plankton with more resistance
to ultraviolet radiation will soon
emerge––but soon, in evolutionary time,
may be too long for whales already on the
brink of extinction.