1. Taste & Smell

2. Smell vs. Taste? Nose Sensors in the Olfactory Epithelium Many uses, including food location Nose Sensors in the Olfactory Epithelium Many uses, including food location Mouth, & many places Taste buds SCC Primarily for feeding Mouth, & many places Taste buds SCC Primarily for feeding

4. Water Flow Olfactory Epithelium

5. Flaps Flaps direct water through the nares and over the olfactory epithelium Water Flow

6. Relies Heavily On Smell Smell not important

9. Olfactory Epithelium Ciliated Cells Molecules Whooshing by in the Water Nerves to the brain

11. Every Odor Molecule is a Little Bit Different

12. Molecule “ keys” fit in olfactory cell “locks” and the fish perceives the smell of red squares, yellow circles, and purple triangles. This fish can’t smell or. Nerves to the brain

14. 050 0

15. Amino acids: The building blocks of protein. Some amino acids are more stimulatory than others. Steroids: Some fish are highly sensitive to hormones especially those related to reproductive activities –Prostaglandins: Hormones released by female fish upon ovulation.

16. Amino acids at concentrations of 1 part in 200,000,000,000 steroid hormones at 1 in 30,000,000,000,000

17. 1 in 200 billion = 6 mg/acre-ft 1 in 30 Trillion = 0.04mg/ acre ft 800,000,000,000,000 molecules/tsp 5,600,000,000 molecules/tsp

20. Taste Bud Nerve Dermis Epidermis Water

22. What Can They Taste ?

23. sweet, sour, bitter, salty, uma Amino acids Steroids: Sex hormones Organic acids and nucleotides: Carbon Dioxide: ?? Peptide toxins: Like marine puffer toxin

25. Solitary Chemoreceptor Cells: SCC Dispersed on external surface of fish as well as on gills and in the oral cavity. These cells are sensitive to amino acids in some species but not others. They are especially adept at detecting fish mucus and some organic acids.

26. Rockling 6 million SCC dorsal fin Prey detection

28. Dorsal fin -Mucus and bile -Predator avoidance

29. 100 per square millimeter on minnows and carp!

30. Smell in Action

31. Salmon Migration

36. 2,300 miles Yukon River

38. Snake River Headwaters Pacific

39. Life Cycles

40. Eggs: found in a redd Alevin: fry with yolk Parr: Fingerlings in fresh water, black bars Smolt: Fingerling ready for the sea, silver Adult: In the sea

41. Spawns and then dies Parr

42. Does not die, returns to the sea

43. Alevin

45. Parr

47. Smolt

51. Imprinting Theory Each stream has a unique chemical signature Young salmon learn the smell of their river Later as adults they home in on that smell and return home Each stream has a unique chemical signature Young salmon learn the smell of their river Later as adults they home in on that smell and return home

52. Imprinting

53. Pheromone Theory Young salmon live in the river for 2-5 years before migrating Young salmon are genetically similar to the adult salmon in the sea Young salmon release pheromones specific to their population Mature salmon smell the young and find the stream Young salmon live in the river for 2-5 years before migrating Young salmon are genetically similar to the adult salmon in the sea Young salmon release pheromones specific to their population Mature salmon smell the young and find the stream

54. Pheromone

55. Homing Theories Imprinting: Salmon smell the stream Pheromone: Salmon smell their kin Which is right?

56. Stream Odorant Experiments

57. Pheromone: Kin recognition

59. Adult Ranges of Pacific Salmon

64. S N

68. QUIZ Difference between taste and smell Lock and Key Functions of taste and smell Salmon life cycle (egg, alevin, parr, smolt adult) Salmon migration

69. Smell Nares and SSC Lock and key

70. Taste Barbles, lips, mouth, skin Mostly for food Also lock and key

71. Taste and Smell Safety –Fright Reaction –Toxin detection Feeding –Finding Food –Testing food Reproduction –Kin recognition –Homing –Reproductive Hormones

72. Eggs: found in a redd Alevin: fry with yolk Parr: Fingerlings in fresh water, black bars Smolt: Fingerling ready for the sea, silver Adult: In the sea