By: Dustin Wylde & Ryan Livingston IB 463 Itchology

Protcanthopterygii Esociformes – (2 families, 10 species) muskie, pike, mudminnows Osmeriformes – (13 families, 236 species) smelts Salmoniformes – (1 family, 66 species) trout, salmon, whitefish, graylings Overall characteristics lack spines Cycloid scales (smooth outer edges) Physotomous gas bladder

Esociformes Inhabit FW Median fins located relatively far back on body

Esociformes cont. Pike Ambush predators Elongate snout with teeth used to impale prey Quick acceleration in a straight line Northern Pike (Esox lucius) Widespread distribution Also predatorial

Northern Pike vs. Chain Pickerel Esox lucius Esox niger

Esociformes cont. Mudminnows Small (less than 20cm) Ability to survive in low O2 enviroments

Osmeriformes Very diverse group (marine, FW, diadromous) Small, silvery, elongate fish that swim H 2 O column Eggs with adhesive membrane

Barreleyes & Platytroctids Barreleyes Elongate tubular eyes Platytroctids Blue-green luminous liquid in papilla at end of lateral line people.whitman.edu

Osmeriformes cont. Lepidogalaxiid – salamanderfish Australia Lacks eye muscles, can turn head 90 degrees Pond dries out: bury in mud

Salmoniformes Very important fish, both commercially and ecolgically Adipose fin Three different families Coregonid whitefishes – zooplanktivours Thymallid graylings Salmonid salmons

Andromous Oceanic migrations of thousands of kilometers Morphological variation between males and females pond.dnr.cornell.edu

Salmon Life-History Born in FW, live in oceans, then return to birth- stream, spawn and die During migration the salmon do not eat Females clear a nest or redd in clean gravel, males will compete to spawn with multiple females Fry will spend several months growing and then migrate to open ocean

Coho/Sockeye Salmon Spawning ure=related ure=related

Salmon Fisheries Salmon very important commercial fish, eaten/harvested all over world Problem: sea lice are causing the decline of salmon populations Naturally sea lice occur in low percentages, however becoming more common Fisheries lack genetic diversity (RI)

Other Salmon Concerns Dams, barriers, weirs block migration In NA several species have been reduced due to introduction of predators, competitors and parasitic lampreys Getting eaten by Bear Grylls

Review Questions: 1) Describe life-history of an Atlantic Salmon. 2) What species of fish has the largest fresh water distribution? 3) What are some problems facing salmon populations today? 4) Describe the preditorial strategy of a Northern Pike? 5) List two things that are very unusual about the salamanderfish?

References Collette, Bruce B., Douglas E. Facey, and Gene S. Helfman. The Diversity of Fishes. Malden: Blackwell Publishing, Fuller Becky, and et al. IB 463 Protcanthopterygii slides Suarez, Andrew. IB 429 Lecture 15: Habitat Selection