"There is a small window of opportunity," said aquarist and marine biologist 
Evonne Mochon Collura, who took over responsibility for the Coastal 
Waters gallery this year.  "You need to let the parents care for the eggs to a 
certain point, but if you wait too long, the emerging larvae disappear due to predation." 
 
Evonne Mochon Collura, also responsible for the care and incubation of a 
highly endangered Vietnamese Leaf Turtle here last year, is becoming known
as the "Aquarium Midwife" for her ability to anticipate and recognize subtle
changes in animal behavior that indicate reproduction is about to occur. "In 
previous years we missed the hatch," said Collura. "Wolf-eel eggs normally hatch between week 13 and 16. One egg mass was consumed, and
another hatched earlier than expected. Because we could never perfectly 
mimic the maternal care, we don’t want to pull the eggs too soon, either, so
we waited as long as possible to pull the mass." 

Collura estimated the mass contains up to 10,000 eggs. 
 
Wolf-eels are not a wolf, not a true eel and they’re not really dangerous 
unless provoked. In spite of their ferocious appearance, wolf-eels are very 
shy and docile. At the Oregon Coast Aquarium you can often see their heads
poking out of a hole in the reef of the Aquarium displays. Wolf-eels are very 
involved parents. The male and female take turns coiling and oxygenating the eggs, while the other guards. 
 
Collura noticed a change in behavior and suspected the presence of
eggs when the female stopped leaving her den to feed. Removing the eggs can
be tricky, too; wolf-eels have very sharp teeth and a powerful bite suited to 
crushing prey. However, Collura said the wolf-eels on exhibit prefer squid 
and are used to being hand-fed. "These wolf-eels are quite tame and will take food from my hand, but I always keep my eye on their teeth!" 

She stuffed the squid mantle with other food, since squid isn’t highly nutritious. She lured them out of the den with squid, but ran out of food before removing the egg mass. Ultimately, she reached into the den, put her hands behind the male’s pectoral fins and gently pulled him out. She did the same thing to the female who immediately wrapped her tail around the egg mass. 

"That helped me get the mass out; I just pulled the female forward and 
captured the egg mass at the same time. After I took the eggs out, I stayed 
with the pair for a while and played with their tails and fins," said Collura. "I
hate to anthropomorphize, but I felt I needed to make amends with them -
they’re very smart!" 

By all appearances the eels were back to normal after a short time. Collura said the female looked for the eggs briefly, but quickly returned to normal 
behavior with her mate. Wolf-eels tend to pair with one mate. "But 
sometimes, there’s a soap opera and two females will compete for one male," according to Collura.
 
The hatchlings resembled tiny tadpoles at first but are now looking more and
more like small wolf-eels, measuring about 1-2 inches in length. They will 
reach 12 – 18 inches in length by the first year; will begin pairing at about four
years old and laying eggs by age seven. Wolf-eels live about 20 years and 
reach lengths of 6 – 8 feet long at maturity. Some of the baby wolf-eels will 
eventually be shipped to other Aquariums, some will stay here at the Oregon 
Coast Aquarium and the Aquarium will look into releasing some into the 
appropriate habitat off the coast of Oregon. 
 
The Oregon Coast Aquarium is a 501(c)(3) not-for-profit educational 
attraction dedicated to the highest quality aquatic and marine science 
programs for recreation and education so the public better understands,
cherishes, and conserves the world’s natural marine and coastal 
resources.      
 
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Photo Caption:  An adult wolf-eel with inset photo of hatchlings at the Oregon Coast Aquarium

The above text and photos were supplied by the Oregon Coast Aquarium