Expectations: 1. Listen carefully 2. Work hard 3. Be responsible Life Cycle: Lesson 11The Fish
Review: We learned the butterfly is another animal that undergoes a complete metamorphosis. There are four stages in a butterfly's life cycle; egg, caterpillar, chrysalis, and adult. We learned that butterflies have scaly wings and can taste with their feet!
Make Predictions: We learned about the needs of fish and the special ways they meet those needs. Now we want to know about their life cycle. What can you guess or predict based on other animals we have looked at. Do you think this animal will go through a metamorphosis like the butterfly?
Observe: http://youtu.be/EqmGSexPaEk Salmon life cycle: What did we learn?
Salmon life cycle: Egg, fry fish, fingerling, adult, spawning. Salmon live in freshwater at first then their body changes to live in salt water. They lay the eggs in the same place that they hatched. Do all fish have the same life cycle?
Observe: the guppy http://youtu.be/WBZy7y-FZp8
Fish Live their whole lives in water. They have gills, like amphibians, but fish never develop lungs. Some fish lay eggs, other fish are born live. When fish have babies or lay eggs it is called spawning.
Basic Fish Life Cycle: Larval fish- live off a yolk sac attached to them until the yolk sac is fully absorbed Egg-the fertilized egg develops into a fish either inside the female fish or outside in the water. Fry- have fully absorbed their yolk and now eat on their own Adult-when fish are able to reproduce or spawn. Juvenile- time spent developing from fry into adults
Salmon Life Cycle: A Closer Look Parr-fry fish are camouflaged and leave the nest to find food. Females lay thousands of eggs in a nest dug in stream bed gravel. Alevin-newly hatched salmon have food sac attached and stay in the nest. Adult- salmon grow and mature in the ocean. When they are mature they return to their birth place to spawn. Smolt- Silver colored fish swim downstream and their body changes (smoltification) to let them survive in the ocean.
Guppy Life Cycle: A Closer Look Fry- the mother gives birth to a live baby, the yolk is still attached but is fully absorbed within a few hours. Egg-develops inside the mother for around 28 days. Adult- when they've reached full size they now have the ability to reproduce. Juvenile- grows and develops until it reaches adulthood, about 3 months for females, 6 weeks for males.
What have we learned? Each fish species reproduces in a unique way to best fit their habitat for spawning and their babies. Some fish hatch from eggs, others are born live from their mothers. We learned a fry is a baby fish that has used up its yolk sac. We learned that when fish reproduce it is called spawning.
Assignment: Draw each stage of the salmon life cycle and write one sentence describing it. http://www.tfsd.k12.id.us/ol/O%27Leary%20Web%20Tech%20Fishtopia/lifecycle.html Go to: http://sea.sheddaquarium.org/sea/buildafish/flash.html Build a fish and see if you can keep it alive by eating the right foods and steering clear of predators.
I had fun learning and working with you today! Keep your eyes open, scientist! I will see you next lesson.