The Rainbow Smelt (Osmerus mordax) enjoys a widespread dispersal across the North American watersheds, including the tributaries of the Atlantic, Pacific and even Arctic oceans. While native to Maine, including one of the few landlocked populations, the prolific smelt has through the years expanded, by the hand of man, into non-native areas, such as the Great Lakes.
Maine smelt can grow to a median size of 6-8 inches in length, depending on the presence of optimal environmental factors, including abundant food, clean water, absence of prey species and decreased competition from other fish species. Rainbow smelt in some northern Maine lakes have been known to grow to an impressive 14 inches and live for over seven years!
The rainbow smelt’s name comes from the iridescent purple, pink, and blue reflections on the fish’s sides. While this oddly bright coloration may appear to poorly camouflage the smelt from predators, scientist predict that since the rainbow smelt is a “schooling” species, the shimmering pattern acts to confuse prey, allowing the school to more easily escape predation.
Though relative small in size, rainbow smelt posses strong jaws lined with pointed teeth. Though juveniles feed mostly on plankton, adults aggressively feed on worms, insects and even small fish. In turn rainbow smelt are heavily preyed upon by almost all Maine fish species, making them an all time favorite bait for anglers.
Shortly after ice out, the lower sections of streams can sometimes be black with thousands of rainbow smelt as they prepare to spawn. The female smelt release eggs that instantly attach to the streams gravel, sand or even submerged vegetation. The male smelt then haphazardly release milt (sperm) that fertilizes the eggs. Both males and females then leave the eggs unattended and the eggs hatch 1–4 weeks later, depending on water temperature.
Wildlife Quiz Questions:
1. What is the distribution of the rainbow smelt?
2. Do landlocked populations of rainbow smelt exist?
3. What is the median size of a Maine rainbow smelt?
4. How long can a rainbow smelt grow?
5. How long can a rainbow smelt live?
6. Do rainbow smelt school?
7. What do rainbow smelt eat?
8. How long does it take for fertilized rainbow smelt eggs to hatch?
Wildlife Quiz Answers:
1. The rainbow smelt inhabits the tributaries of the Atlantic, Pacific and Arctic oceans.
2. Yes, Maine has been documented as having one of the few identified populations of landlocked rainbow smelt.
3. Maine rainbow smelt can grow to 6-8 inches in length.
4. A rainbow smelt can grow up to 14 inches.
5. A rainbow smelt can live up to 7 years.
6. Yes, smelt gather together in schools.
7. Rainbow smelt eat worms, insects and even small fish.
8. Rainbow smelt eggs hatch in 1-4 weeks, depending on water temperature.