Diversity of Wisconsin Fishes reproduction habitats Reproduction strategies

1. Diversity of Wisconsin Fishes reproduction habitats Reproduction strategies Early life history- terms Ecology of early life history Lab – Wisconsin fishes part 2 Today Schedule

2. Non-gaurding , Pelagic Alewife - inshore waters, eggs settle High fecundity High early stage mortality Gizzard shad - Often move up rivers, eggs drift down

3. Non-gaurding , Pelagic Freshwater drum eggs float on surface until hatch Paddlefish eggs are sticky when fertilized, adhere to the first thing they touch

4. Non-gaurding , Benthic – fine substrate Spottail shiners spawn on gravel and silt substrates

5. Non-gaurding , Benthic - Crevice Spotfin shiners use rock crevices to hold eggs

6. Non-gaurding , Benthic –vegetation Northern pike prefer flooded vegetation in backwaters

7. Non-gaurding , Benthic –vegetation Banded killifish spawn gets entangled in aquatic vegetation

8. Non-gaurding , Benthic – coarse bottom Lake trout and lake whitefish spawn over large broken coble areas

9. Non-gaurding , Benthic – stream Pacific salmon and brown trout dig redds – clean gravel where stream water upwells

10. Non-gaurding , Benthic – stream Brook trout exclusively use groundwater upwelling areas in lakes and streams

11. Guarding , Nests – nests of plants Guarding means higher survival Sticklebacks make nests of algae and macrophytes and then lay eggs inside the nests

12. Gaurding , Benthic – Underside of rocks Both round gobies and Johnny darters spawn under rocks, attaching the eggs to the underside of the rocks Aggressive defense can incur high costs to parents or death

13. Gaurding , Nests – gravel Common in centrachids also lamprey, nests are often fanned to increase water flow and remove sediments American brook lamprey Smallmouth bass

14. Gaurding , Nests – Holes and burrows Catfish and bullheads make burrows or use existing holes Noodling Time: http://www.youtube.com/watch?v=zOjA8Puh1BM

15. Gaurding , Nest – fine sediment Crappie nests associated with vertical vegetation in fine sediments

16. Livebearers , (none native) Mosquitofish 60 -100 progeny per brood, born live, male has modified anal fin to impregnate female Why bear live young?

17. Life history strategies Multiple strategies: Bluegill – parental care or Cuckolder Female mimic http://publish.uwo.ca/~bneff/research_beea.htm

18. Life history strategies Multiple strategies: Pacific salmon ‘Jack’ – 2 year old male Normal 5-6 year old male Female mimic

19. Spawning variants How often: Semelparous = once, Iteroparous = more then once

20. Fish evolve to spawn in different locations Temiscamie – strain Tributary spawner Little Tupper strain Shoal spawner Assinica- strain Outlet spawner Why...think about the emerged fry!

21. Early life history

22. Same basic pattern Eggs Larvae (alevin) Juvenile Adult Snook Salmon

23. Diverse Larvae

24. Majority of mortality occurs in early life Most fish are r selected – lots of offspring, little care, few make it Verhulstequation Small changes in survival at any stage = big difference in year class strength

25. Year class strength Measure or index at some point when fish can be easily caught. Long term data is critical since each year is only one data point What could influence year class strength? At what stages?

26. Factors that influence early life survival Match/Mismatch Hypothesis Conditions match what is needed Temperature-How quickly adult fish mature and spawn-How quickly eggs hatch-Growth rate of larvae and YOY Food availability-Is the right food available once yolk sac is used up?-As they grow does the food out grow them? Water level-Eggs can be left high and dry or smothered? Predation-Do larvae face a predator gauntlet?

27. Year class strength: egg stage gravel size influences survival from egg to larvae

28. Year class strength: YOY – young of year River flow influences survival of young of year

29. Year class strength: temperature

30. Food Abundance Fluctuations

31. Predation What about larval lake trout? Must fill swim bladder at surface (physoclistous ) Great lakes LT spawning reefs Lake trout eat alewives…right?

32. Match/Mismatch Yellow perch hatch Eat small copepods, then switch to Daphnia Yellow perch hatch Eat small copepods but Daphnia show up too late

33. Wisconsin Fishes part 2

34. Esocidae (Pikes) Grass pickerel Muskellunge Northern pike

35. ID’ing esocids PoresPickerel – 4Pike – 5Muskie – 6-9 Northern pike Branchial. RaysPickerel – 12Pike – 14-16Muskie – 16-19 Muskellunge Identify with pores and or branchiostegal rays

36. Umbridae (Mudminnows) Central mudminnow Fin placement Homocercal tail

37. Lottidae (Burbot) Homocercal tail Long continuous anal and dorsal fins Single chin barbel

38. Aphredoderidae (Pirate perch) Big dorsal Starts here Ends here "Migrating anus"

39. Percopsidae (Trout-perch) Trout-perch Big head, big eye, big mouth Adipose fin

40. Centrarchidae – 4 genera, 8 species Ambloplites Micropterus Pomoxis Lepomis

41. Micropterus Largemouth bass Maxilla beyond eye Maxilla to middle of eye Smallmouth bass

42. Lepomis Green Sunfish Pumpkinseed Bluegill

43. Ambloplites – rock bass Solid, no light margin Rounded pectoral

44. Percidae – 5 genera, 8 species Sander Perca Percina Crystallaria Etheostoma

45. Sander Walleye White tip Sauger No-White tip More mottled

46. Darters Rainbow darter Johnny darter Fantail darter Crystal darter

47. Moronidae (Temperate Basses) Broken and offset Yellow bass Not offset White bass

48. Sciaenidae (Freshwater Drum) Elongated ray on pelvic fin

49. Gobiidae (Gobies) Distinct head shape differences Round goby Tubenose goby

50. Gasterosteidae (Sticklebacks) Ninespine stickleback Uh…count the spines Brook stickleback