2. Deep-seaDeep-sea lights Deep-sea fishesfishes

3. Hearing, touch, taste, etc.

4. water is 83x denser than air sound travels 4.5x faster in water - not rapidly attenuated; difficult to localize low frequencies propagate better, faster Sound transmission in water

5. water is 100x denser than air sound travels 4.5x faster in water - not rapidly attenuated; difficult to localize low frequencies propagate better, faster sound: small vibrations with particle displacement near source - “near field” (a few meters) sound pressure component – “far field” Sound transmission in water

6. Hearing and lateral line (acoustico-lateralis system) Lateral line – sound reception in far field - "distant touch" detects particle displacement Ears - sound reception in near field - acceleration, equilibrium detects pressure waves

7. Lateral line system superficial (free) neuromasts on body surface, or in shallow pits or grooves canal neuromasts in lateral line Perciformes, Centrarchidae: black crappie Perciformes, Moronidae: white perch

8. superficial neuromast

9. canal neuromasts

10. Lateral line system location and type of neuromasts optimized for particular prey, environment, etc. Cypriniformes, Cyprinidae: golden shiner

11. Science, 27 July 2012, p. 409

12. Ears equilibrium and balance: three semicircular canals detect roll, yaw, pitch also acceleration

13. Ears equilibrium and balance: three semicircular canals detect roll, yaw, pitch also acceleration semicircular canals utriculus (lapillus) pars superior (balance, acceleration)

14. Ears sound reception fish vibrates with sounds in water otoliths vibrate slower, impinge on sensory cilia semicircular canals utriculus (lapillus) lagena (astericus) sacculus (sagitta) pars superior (balance, acceleration) pars inferior (hearing)

15. Ears equilibrium and balance: three semicircular canals detect roll, yaw, pitch also acceleration sound reception fish vibrates with sounds in water otoliths vibrate slower, impinge on sensory cilia

16. Fig. 3. Schematic illustration of the relationship between the sensory epithelium and the overlying otolith

17. Ears Otoliths

18. Ears hearing sensitivity improved with 1. Weberian apparatus connects air bladder with ear labyrinth present in ostariophysan fishes (Cypriniformes, Characiformes, Siluriformes) gives wide range of hearing (20-7000 Hz)

19. Ears hearing sensitivity improved with 1. Weberian apparatus connects air bladder with ear labyrinth present in ostariophysan fishes gives wide range of hearing (20-7000 Hz) 2. direct connection of swim bladder and ear squirrelfishes (Holocentridae) herrings etc. (Clupeidae)

20. Ears hearing sensitivity improved with 1. Weberian apparatus connects air bladder with ear labyrinth present in ostariophysan fishes gives wide range of hearing (20-7000 Hz) 2. direct connection of swim bladder and ear 3. airbreathers maintain bubble in superbranchial cavity, near to ear 4. no connection - lower frequency range, lower response to high frequencies

21. Sound production homepage.univie.ac.at/friedrich.ladich/Topics.htm http://www.fishecology.org/soniferous/waquoitposter.htm

22. Sound production stridulation due to friction - grinding of teeth - movement of fin spine in socket, etc. (catfish, triggerfish, filefish, sticklebacks)

23. Sound production stridulation due to friction - grinding of teeth - movement of fin spine in socket, etc. (catfish, triggerfish, filefish, sticklebacks) via gas bladder - release of air

24. Sound production stridulation due to friction - grinding of teeth - movement of fin spine in socket, etc. (catfish, triggerfish, filefish, sticklebacks) via gas bladder - release of air - vibration of muscles (toadfishes, Batrachoididae; searobins, Triglidae; drum, Sciaenidae) Perciformes, Sciaenidae – freshwater drum)

25. Sound production stridulation due to friction - grinding of teeth - movement of fin spine in socket, etc. (catfish, triggerfish, filefish, sticklebacks) via gas bladder - release of air - vibration of muscles incidental to other behaviors - swimming and muscular motion - breaking surface and splashing - feeding, e.g., coral and crustacean-feeders - production of bubbles

26. Sound production Technology for detection is rapidly advancing Provides data on presence, distribution, (density), behavior Remote monitoring, nocturnal observations Problems associated with human sound production boat motors sonar dredging, construction naval activities

27. Graham A L, Cooke S J. 2008 The effects of noise disturbance from various recreational boating activities common to inland waters on the cardiac physiology of a freshwater fish, the largemouth bass (Micropterus salmoides) Aquatic Conservation - Marine And Freshwater Ecosystems 18: 1315-1324 1.organism-level cardiovascular disturbance associated with different recreational boating activities using largemouth bass (Micropterus salmoides). 2.Cardiac output (heart rate and stroke volume) monitored in real time as fish responses to canoe paddling, trolling motor, and combustion engine (9.9 hp)) for 60s. 3.Exposure to each of the treatments resulted in dramatic increase in heart rate and a slight decrease in stroke volume canoe < trolling motor < combustion engine Time to recover: canoe ~15 min, trolling motor ~ 25 min, combustion engine ~ 40 min 4.Fish experienced sublethal physiological disturbances in response to the noise from recreational boating activities. Boating activities can have ecological and environmental consequences; their use may not be compatible with aquatic protected areas.

28. Olfaction (= chemoreception at "long" range/gradients) more sensitive than taste used for: food finding migration, e.g., salmon intra, interspecific communication

29. Olfaction (= chemoreception at "long" range/gradients) more sensitive than taste used for: food finding migration, e.g., salmon intra, interspecific communication “Schreckstoff” alarm pheromones (Ostariophysi) originate in specialized ‘club’ cells in skin, released whenfish is damaged - effect is to alert other conspecifics potent highly specific (generally species-specific) pass through gut of northern pike

30. Taste (= chemoreception at close range) taste organs can reside on exterior surfaces: barbels of bottom-dwelling fishes lips of suckers over much of body of ictalurids

31. use of taste and smell: communication individual recognition, especially of mates species recognition, esp. schooling species offspring recognition (cichlids) scent mark territories (gobies) dominant-subordinate relationships aggression-inhibiting pheromone produced by bullheads living in groups

32. Other cutaneous senses temperature teleost cutaneous temp. sensitivity to 0.03  C change can distinguish rise from a fall in temperature elasmobranchs detect temperature change with ampullae of Lorenzini

33. Other cutaneous senses touch few detectors – shark fins; head, barbels of bullheads mating behaviors (use of breeding tubercules) parent-young communication in catfish, cichlids, damselfishes

34. Electrogeneration and electroreception

36. chum source electrodes

37. Production of electricity muscular contractions generate electrical signal ‘stack’ specialized cells (electrocytes) to amplify signal (in series) with insulating material around them

38. Production of electricity Types of electricity produced: strong current - for stunning prey or escaping predators 10 to several hundred volts in ‘volleys’ of discharges

39. Production of electricity Types of electricity produced: strong current - for stunning prey or escaping predators weak current - for electrolocation - conspecifics in school, - prey emit continuous signal; objects entering field are detected by distortion of field discharge 200 - 1600 cycles/sec

40. Production of electricity used by most elasmobranches, some teleosts Osteoglossiformes (Mormyridae) - African electric fishes Rajiiformes (Rajiidae) – electric skates Gymnotiformes (Gymnotidae) – electric eels Siluriformes (Malapteruridae) - electric catfish Perciformes (Uranoscopidae) - stargazers Torpediniformes (4 families) – electric rays (Gymnarchidae) strong-electric fishes weak-electric fishes

41. Production of electricity electricity-producing fishes tend to be slow-moving, sedentary active at night, or in murky water w. low visibility have thick skin: good insulator emhance signal-to-noise ratio with stiffened body

42. Electroreception types of signals received movement through earth’s magnetic field current from muscular activity of other fish (prey) signals produced by conspecifics frequency shifts identify individuals

43. Electroreception detection via external pit organs ampullae of Lorenzini in elasmobranches open to surrounding water via canals, filled w. conductive gel sensitive to temperature change mechanical and weak electrical stimuli changes in salinity

44. Electroreception detection via external pit organs saltwater teleosts, elasmobranches – long, ~ 5- 160 mm skin has low resistance tissues have high resistance, relative to salt water thus organs must penetrate skin to get voltage drop in freshwater teleosts - quite short, ~300 microns tissues are good conductors relative to water skin is highly resistive - so high voltage drop across skin, detected w. shallow organ