Name That Fish : Identify living things using an existing classification key, and explain the rationale used.

Transcription

1 Outcome: : Identify living things using an existing classification key, and explain the rationale used. Materials: writing utensil Teacher Instructions: 1. Make a class set of pages Instruct students to clear their desks of everything except a pen or pencil. 3. Hand out pages 2-4. Page 2 contains pictures of Manitoba fish species labeled from - L. Students will use the Key to Manitoba Fish Species on page 3 to identify these fish and write down the correct names in the spaces provided on page Students will also provide rationales for their choices in the spaces provided on page 4. For example, next to Sturgeon they should write Tail fin; upper lobe larger as the Key indicates for sturgeon. They should notice that in the picture of the sturgeon, it does in fact have a tail fin with a larger upper lobe rather than symmetrical lobes. n answer key is provided on page 5. Teacher Background Information: Using the Key to Manitoba Fish Species If you observe the Key to Manitoba Fish Species you will notice that the lake sturgeon is the only fish species with a heterocercal tail (the upper lobe larger than the lower lobe - like a shark s tail). This separates it from all other Manitoba fish species. The next main branches of the fish family tree are based on whether a species has an adipose fin or not. gain, this is an obvious visual clue for classifying fish. Barbels and spines are then used to subdivide branches, then teeth or no teeth, scales or no scales, etc. Notice that the further you are along the branching process, the more specific the clues must be to determine the species. For example, it is not just whether the fish has spines, it is where those spines are located. The colour of a fish is usually the last thing used to identify a species. Colours can be misleading because they can change slightly depending on the habitat the fish is found in, what they are eating, the time of year (e.g. spawning/breeding colours are usually brighter than colours at other times of the year), etc. For this reason, only obvious colouration features that are fairly reliable (e.g. white fin edges, spots, stripes) are used in the key. 1 of 5

2 B C D E F G H I J K L 2 of 5

3 Lake Trout Key to Manitoba Fish Species Tail deeply forked Dorsal fin near tail Light spots on dark body Northern Pike White edge on lower fins Red spots with blue circles on sides Brook Trout Light body and spots if present are dark Muskellunge Tail square or slightly notched Pink, yellow or white spots on side rctic Char Front of dorsal fin ahead of anal fin Mooneye Pale red spots and slightly notched tail Splake Teeth Dorsal fin behind front of anal fin Goldeye Teeth No white edge on fins Body light or silver colour Kokanee Pink flash on side and small black spots Rainbow Trout Dorsal fin centered No teeth Single stiff spine on dorsal and anal fin Carp Body dark colour Large dark spots on yellow-brown background Brown Trout Scales No spines on fins Sucker Large dorsal fin rctic Grayling No scales Burbot Tail fin. Upper lobe larger Sturgeon No teeth No Barbels dipose fin long and thin an d connected to tail fin Normal dorsal fin Stonecat Mouth above end of snout Mouth below end of snout Tullibee Whitefish No spines in anal fin Strong sharp teeth Spiny dorsal fin a series of black spots Spiny dorsal fin solid light colour, dark spot at rear base Sauger Walleye S T R T Tail fin. Even or symmetrical dipose fin Barbels dipose fin small and distinctive Tail fin deeply forked Tail fin square Channel Catfish Bullhead Soft dorsal fin Teeth not as pronounced and dark vertical bars Dorsal fins separate and body light in colour Dark lateral lines No lines Perch White Bass Freshwater Drum No adipose fin Spines in anal fin Mouth extends to eye Smallmouth Bass Spiny dorsal fin Dorsal fins connected and body dark in colour Notch in dorsal fin Mouth extends past eye Largemouth Bass Eye red Rock Bass Continuous dorsal fin Eye yellow Black Crappie 3 of 5

4 B C D E F G H I J K L Name of Fish Student Name: Rationale 4 of 5

5 B C D E F G H I J K L Name of Fish Northern Pike Brook Trout Bullhead Goldeye Perch Rock Bass Sturgeon Rainbow Trout Carp Walleye Sucker Catfish Rationale dorsal fin near tail, light spots dark body symmetrical tail, adipose fin, no barbels, teeth, white edge on fins, square tail, red spots with blue circles on side symmetrical tail, adipose fin, barbels, tail fin square dorsal fin in centre, teeth, dorsal fin behind front of anal fin symmetrical tail, no adipose fin, spiny dorsal fin, no spines in anal fin, teeth not as noticeable and dark vertical bars symmetrical tail, no adipose fin, spiny dorsal fin, spines in anal fin, dorsal fins connected, continuous dorsal fin, eyes red tail fin, upper lobe larger symmetrical tail, adipose fin, no barbels, teeth, no white edge on fins, body dark, pink flash and small black spots dorsal fin in centre, no teeth, single stiff spine on dorsal and anal fin symmetrical tail, no adipose fin, spiny dorsal fin, no spines in anal fin, strong sharp teeth, dark spot at base of dorsal fin dorsal fin in centre, no teeth, no spines on fins symmetrical tail, adipose fin, barbels, tail fin deeply forked Teacher nswer Key 5 of 5