Trout in the Classroom

This is one of many programs that are part of the Y’s Bonni’s Garden initiative to help students understand the natural world, live healthy lives, and be good stewards of our environment. Trout in the Classroom allows our students to receive eyed-eggs from hatcheries. Our students support and witness the amazing transformation of eggs, alevin, and fingerlings. Students learn about the nitrogen cycle and water chemistry and care for trout until they are ready to be released. We keep just a few trophy trout in our large tank. The students currently have two trophy trout, M2 and Boots. The largest is approximately 14 inches in length. Rainbow Trout are extremely temperamental to their environment, any change in temperature or pollutants in the water can affect the fish. The water temperature of the tank is set at 53 degrees! Rainbow Trout live in cold water in the streams and rivers of Idaho.

Taxonomy

Fish in the Pacific Salmon (Oncorhynchus) Genus
Kingdom: Animalia
Phylum: Craniata
Class: Actinopterygii
Order: Salmoniformes
Family: Salmonidae
Species: Oncorhynchus mykiss

The Rainbow Trout Life cycle is simple. The female digs a redd (nest) and deposits her eggs. The male fertilises them with milt (sperm). Eggs take 20–100 days to hatch, depending on water temperature. Once hatched the alevins (fry with yolk sacs attached) stay in the gravel for two to three weeks and feed off their yolk sacs. When the yolks are nearly used up, the young trout emerge as free-swimming fry. When a fry grows to 2-5 inches, it becomes a fingerling. When it develops large dark markings, it then becomes a parr. When the Rainbow Trout swims back to its original spawning area it is an adult.

Adult freshwater stream Rainbow Trout average between 1 and 5 pounds (0.5 and 2.3 kg), while lake-dwelling and anadromous (sea-run) forms may reach 20 pounds (9 kg). Coloration varies based on subspecies, forms and habitat. Adult fish are distinguished by a broad reddish stripe along the lateral line, from gills to the tail, which is most vivid in breeding males.

Wild-caught and hatchery-reared forms of the species have been transplanted and introduced for food or sport in at least 45 countries and every continent except Antarctica. Some Rainbow Trout populations have been introduced outside their native range in the United States, Southern Europe, Australia, New Zealand and South America. Introduced populations may affect native species by preying on them, out-competing them, transmitting contagious diseases, or hybridizing with closely related species and subspecies.

How can I participate? Students in the Y’s After School Club, Nature Explorer Camp, and other programs all participate in Bonni’s Garden Activities, including Trout in the Classroom.