SPECIES Here is a sampling of some crayfish species that are suitable for the aquarium and can be easily obtained.
Cambarellus patzcuarensis hails from Mexico
and can add color to a planted setup.
RED CLAW CRAYFISH CHERAX QUADRICARINATUS
Red claw crayfish Cherax quadricarinatus may be dark blue to
brown, with males bearing a distinctive red patch along the side
of each claw. This crayfish grows to 10 inches long. It is native to
north Australian lakes and streams, but a subspecies is believed
to occur in Thailand. It is best kept at temperatures between 59°
to 85°F. Most of the individuals available in the European and
American hobby are aquacultured in Australia and New Guinea.
America. Oddly, crayfish are not known to occur in much of Asia
or the Indian subcontinent, or in any part of Antarctica or Africa
(except for Madagascar).
Most crayfish are nocturnal, meaning they forage at night. They
are also typically solitary, not living in groups.
BLUE KNIGHT LOBSTER CHERAX SP.
The blue knight lobster Cherax sp. is a showy variety that
grows to a foot long and requires at least a 50-gallon or larger
aquarium. Provide a medium-size grain substrate for burrowing. It
is moderately aggressive, so use caution when stocking with other
animals. The blue knight lobster is native to New Guinean streams.
It is best kept at 68° to 75°F.
Known as shredders, crayfish usually tear apart and ingest
decomposing leafy and woody material. They don’t digest this
material but get sustenance from the bacteria, algae, and fungi
living on it. They include live plant matter in their diet as well, and
it is thought that this is where they obtain most of the pigments
used for their own coloration.
Studies indicate that most are opportunistic predators/scavengers
that depend upon a variety of live food items (e.g., daphnia,
insects, snails, and worms) and dead animal matter to fulfill their
nutritional needs. It appears that a varied and properly balanced diet
is a fundamental necessity for their long-term survival in captivity.
Their diet can be enriched cheaply and easily with supplements of
boiled carrots, corn, and beans.
These reticent animals appreciate cover provided by stones, wood,
and plants. When the appropriate materials are made available to
them, many crayfish will build chimney-like burrows that may be 4
to 6 inches in diameter and reach 18 inches in depth. Some (such
as Engaeus spp.) are capable of excavating huge, terrestrial hillside
burrows. Certain types (especially the wetland crayfishes) spend a
considerable amount of time in these structures.
To some hobbyists, these are creatures that will do nothing but
hide, only venturing out at nighttime to demolish the aquarist’s
latest aquascape work. Others perceive the creatures’ activities as
healthy and natural, finding the burrows to be a more beautiful
and interesting part of the aquascape than anything they could
BLACK SCORPION LOBSTER CHERAX SP.
The black scorpion lobster Cherax sp. also grows to a foot long
and requires a big aquarium. Provide a medium-grain substrate
for burrowing. This moderately aggressive crayfish is native to
northeast Australian streams and likes temperatures of 68° to 75°F.
The red claw crayfish Cherax quadricarinatus
features a conspicuous patch of color that
makes it highly recognizable.
TASMANIAN GIANT CRAYFISH ASTACOPSIS GOULDI
The Tasmanian giant crayfish Astacopsis gouldi, a true titan,
is the largest known freshwater invertebrate at 6 to 8 pounds. It
requires a 200-gallon aquarium at minimum. Despite its great
size, it is primarily a detritivore and presents few exacting dietary
demands in captivity. It is known to be slow growing, but may live
for over 30 years. Provide large sections of sunken wood for cover.
These monsters are native to slow-moving waters on the island of
Tasmania and do best at 59° to 75°F.
Unlike other crustaceans, crayfish do not have a larval stage.
Instead, the hatchlings (which are like miniature adults) stay with
the mother at the beginning of their lives. Juvenile crayfish are
nearly independent upon hatching; some varieties may possess the
ability to filter food items as minute as diatoms. Crayfish have been
successfully cultured on various scales for decades, and are as a rule
much simpler to rear in captivity than shrimps or crabs.
MEXICAN ORANGE DWARF CRAYFISH
A shy but handsome species, the Mexican orange dwarf crayfish
Cambarellus patzcuarensis grows only to 1½ inches long and can
be kept in tanks of 10 gallons or more. Provide extra hiding places
and a fine- to medium-grain substrate for burrowing. It is native to
Mexico and the southern United States, and prefers temperatures
of 68° to 85°F.
Tropical Fish Hobbyist www.tfhmagazine.com