Seeking the truth About the
Feared Piranha
ARTICLE AND *PHOTOGRAPHS BY
PAUL A. ZAHL, Ph.D.
SENIOR NATURAL SCIENTIST
(*) Unless otherwise noted
I STOOD AT THE EDGE of a shrunken lagoon in southern
Paraguay. It was the peak of the dry season, and the water was low and mirror
still, save for an expanding circle here and there caused by the touch of a
dragonfly or the surfacing of a small fish.
Opening my fishing kit, I tied a steel leader to the end of a 20-pound-test
line, then a hook. My knife sliced a cube of bait from a hunk of sinewy local
beef. My rod was a branch trimmed from a nearby thicket.
Unseen in these sullen waters swam piranhas – hungry, as are all fish, but
allegedly a hundred more times more rapacious, attracted to anything fleshy, I
had read, like iron filings drawn to a magnet.
I had heard of the proverbial horror stories: the canoeist suddenly minus a
finger; the cow skeletonized while fording a stream; the swimmer disemboweled by
sudden attack. Nineteenth-century naturalist Alexander Von Humboldt referred to
the piranha as one of South America’s greatest scourges. The words of eminent
ichthyologist Dr. George S. Myers also came to mind: "teeth so sharp and
jaws so strong that it can chop out a piece of flesh from a man or an alligator
as neatly as a razor, or clip off a finger or toe, bone and all, with the
dispatch of a meat cleaver."
Rapacious
killers or creatures much maligned? In an attempt to separate fact from
fancy, the author journeyed across South America studying piranhas, including
Serrasalmus nattereri, considered the most dangerous. These Brazilian
specimens have red undersides
while a Paraquayan example inspected by Dr. Zahl (PHOTO LEFT), has a yellow
belly. (Due to copyright I have substituted an image of the same colored species
now placed as Pygocentrus nattereri).
On the other hand, during repeated visits to, South American
hinterlands, I had also watched Indian children splashing carefree and unharmed
in piranha-inhabited waters (pages 720-21), their mothers waist-deep nearby
rinsing laundry. Brazilian anthropologist Harald Schultz, after spending more
than two decades in piranha country, could write, "In all these years I
have never had a harmful experience with these greatly feared piranhas."
Unspectacular – Except for Its Teeth
Mindful of both sides of the story, I stitched the juicy bait onto my hook and
swung the line out over the lagoon. In a few seconds I felt a tug. I braced and
whipped up the pole. It was disappointingly easy. Onto the bank flew a silvery
fish scarcely larger than my hand?a little creature no more impressive than the
trout of my boyhood days in the Sierra Nevada. But the comparisons stopped when
I caught sight of jaws snapping wildly in their effort to dislodge the hook. Had
my leader not been steel, it could have been severed instantly. "Don’t
touch him!" warned my companion, Senior Juan Pio Rivaldi Blanco, chief of
Paraguay’s Fish and Game, and Fish Breeding Division. His boot came down,
pinning the flapping piranha to the ground. Cautiously he removed the hook,
seized the fish behind the gills, and held it up. Latinized as Serrasalmus
nattereri, this struggling specimen had silvery sides and a yellow belly–
quite unspectacular, except for that mouthful of fiendish teeth. Each was a
razor-keen triangle set so that when its cutting edges met those of opposing
teeth, the shearing power would be all but irresistible (pages 722-3). About a
score of piranha species, differing in head shape, coloration, size, and
temperament, but nearly all possessing that incisive bite, claim a habitat
covering some four million square miles of tropical South America. They are
found wherever fresh water flows or stands– from the lower eastern slopes of
the Andes through Colombia, Venezuela, and the Guianas; south and eastward
across the immense Amazon Basin; into Bolivia, parts of Peru, Paraguay, Uruguay,
and northeastern Argentina (map, page 719). Known as perai in parts of the
Guianas and caribes in several other lands, they take their more common name
from dialects of the Tupi linguistic group, in which, pira means
"fish" and ranha "tooth." Virtually all piranhas belong to
the genus Serrasalmus of the family Characidae, which also includes many
a good-tempered aquarium fish. One of the smaller piranhas, Serrasalmus spilopleura, reaches only
about half the length of the big dark Serrasalmus niger, which
may grow as long as 18 inches and weigh as much as five pounds. In my
experience, the little one was not dangerous; I had encountered it everywhere in
Paraguay, even in the smallest streams. Serrasalmus niger was another
matter; while some of my informants declared it to be among the most harmless,
others gave it a dangerous label. All my experts agreed as to the peril of
dealing with Serrasalmus nattereri, the species that is probably most
responsible for the piranha’s fearsome reputation. Some species have a
tendency to gather in schools, while others are loners, except when lured into a
group by the smell or taste of blood or raw flesh. Some are said to prefer deep
habitats; others seem to frequent the shallows, either turbid or clear. Certain
species appear to seek quiet waters, others the more rapid currents. Some seem
savage; others are only moderately aggressive. Some seem to be omnivorous, but
most are basically flesh eaters with cannibal tendencies.
Opinion Changes in a Split Second
To observe and photograph piranhas in their natural habitats, I planned trips
that would sample the group’s entire geographical range. I would begin along
the Paraguay-Argentina border, then move northward into Brazil, proceeding
eventually into the heartland and the delta islands of the Amazon, and as far
north as Surinam. My finding Serrasalmus spilopleura – the small
innocent one– abundant in Paraguay, I was lulled in my estimate of the piranha
potential. I had often picked this fellow from a net by hand, finding him no
more hostile than a goldfish. Then one day an eyewitness experience changed my
outlook. Driving through Paraguay’s picturesque cattle country a hundred miles
south of the capital city of Asuncion, Senior Rivaldi and I drew up to an
isolated and brooding lagoon. Six or seven fishermen, hip-deep in the water,
were setting a long seine. I approached the net’s onshore anchor man, clad
like the others only in shorts and straw hat.
Click here to
go Page 2
