Physiology of Migration and Behaviour in Fish.pptx

Fish migration is vital for ecosystems and human activities like fishing. Understanding its physiology and behavior is crucial for effective management and conservation. Factors like light, temperature, and water currents influence migration patterns. Exploitation by fisheries relies on predictability, but management must consider ecological importance. Tagging advancements offer insights into movements and behavior. Further research and technology will aid conservation. Fish migration involves various disciplines and highlights the interconnectedness of aquatic ecosystems, emphasizing the need to preserve natural behaviors for environmental health.

1. College of Fisheries Science - Veraval Kamdhenu University Sub: Fish and Shellfish Physiology and Endocrinology (AQC 604) Submitted By Rajesh V. Chudasama, Reg. No. 231303002, Ph.D. (AQC), 1 st Sem. COF-VRL, KU. Submitted To Dr. A. S. Kotiya, Assistant Professor , Fisheries Research and Training Center, Mahuva. Department of Aquaculture 1

2. 2 c Physiology of Migration and Behaviour in Fish

3. Definition: Movement of individuals or groups of animals from one place to another, typically with a regular pattern, such as annually or during specific life stages. Examples: Birds flying long distances between breeding and wintering grounds, insects moving in large numbers without returning to their starting point. c Migration

4. Definition: Movement of fish from one area to another along the horizontal axis, rather than vertical movement within the water column. Characteristics: Fish may move between different habitats, such as from spawning grounds to feeding areas, or in response to environmental factors like temperature or food availability. Importance: Horizontal migrations of fish impact fishing practices and ecosystem dynamics. Contrast with Vertical Movements: While fish also exhibit vertical movements (e.g., swimming deeper during the day and closer to the surface at night), horizontal migrations focus on lateral movements within the water. c Horizontal Migration in Fish

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6. Fish migration refers to the seasonal movement of fish from one place to another. Importance: Helps in predicting future fish populations. Assists in formulating regulations for sustainable fishing practices. Research Areas: Whole group migration studies. Individual fish navigation and sensory mechanisms. Predictive modeling of fish populations. Applications: Fishing industry: Helps fishermen locate fish. Conservation efforts: Guides management strategies. Scientific research: Provides insights into animal behavior. Challenges: Complexity of migration patterns. Relevance of research to practical fishing. Ethical considerations in studying animal behavior. c

7. A. Short-Distance Movement: Definition: Fish species that travel relatively short distances, typically within a few kilometers. Examples: Blennies moving between inshore and offshore areas depending on the season. Importance to Fisheries: Limited impact on fishing practices due to localized movement patterns. c Scales of Movement in Fish

8. B. Moderate-Distance Movement: Definition: Fish species that travel moderate distances, ranging from tens to hundreds of kilometers. Examples: Herring, mackerel, cod, and plaice journeying hundreds of kilometers in temperate waters. Importance to Fisheries: Significant impact on fishing, as movement may require fishermen to adapt their fishing locations. c

9. Long-Distance Movement: Definition: Fish species that undertake extensive migrations, covering thousands of kilometers. Examples: Salmon, eels, tuna, billfishes, and large sharks traveling long distances. Importance to Fisheries: Major influence on fishing practices, as fishermen may need to follow migratory routes to catch these species. c

10. Optimizing Habitat Selection Fish engage in migration to locate optimal habitats for feeding, growth, and reproduction. Varied environmental factors such as water depth, temperature, salinity, and prey availability influence habitat suitability. Migration allows fish to adapt to changing environmental conditions and select habitats that best fulfill their biological requirements. c Way Do Fish Migrate ?

11. Resource Acquisition Movement facilitates access to essential resources like food and shelter. Fish explore different areas to exploit abundant food sources and minimize predation risk. Reproductive Strategies Migration often correlates with reproductive activities, with fish migrating to specific locations for spawning. Spawning grounds provide optimal conditions for egg fertilization, larval development, and offspring survival. c

12. Population Dynamics and Survival Migration helps regulate population density and distribution, reducing competition for resources and minimizing overcrowding. Dispersal to different habitats enhances survival rates and promotes genetic diversity within fish populations. By diversifying their habitat use, fish increase their resilience to environmental fluctuations and anthropogenic impacts. c

13. Physical Factors Temperature Light intensity Photoperiod Water current Turbidity Depth c Factors That Influence Migration Chemical Factors pH Salinity Odour Taste of water Biological Factors Food Memory Maturity Predators Hormones

14. c Fish Migration

15. c Fish Migration

16. Migrate within salt water only Influence of Water Currents: Fish movements, especially during early life stages, are significantly influenced by water currents. Ocean currents, primarily driven by planetary wind systems, play a crucial role in the distribution and migrations of fish stocks. Ocean Currents v/s Tidal Currents: In the open sea, two main current regimes exist: ocean currents and tidal currents. Ocean currents dominate in high seas, while tidal currents are more significant on continental shelves. c Oceanodromous Fish

17. Large-scale flows of water driven by wind patterns and the Earth's rotation. Examples: Major ocean currents like the Gulf Stream and the North Atlantic Drift transport fish larvae from spawning areas to coastal waters where they grow into adults. c Ocean Currents

18. Definition: Caused by the gravitational pull of the moon and the sun, leading to the rise and fall of tides. Role: In shallow shelf seas, tidal currents shape water movements, influencing the drift of fish larvae and aiding mature fish in navigating within their habitats. c Tidal Currents

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20. Bluefin Tuna Extensive migrations in the North Atlantic, with complex patterns challenging previous assumptions about stock mixing. c Case Studies - Oceanodromous Fish

21. North Sea Plaice Migration: Seasonal migration influenced by age and sex, utilizing selective tidal stream transport to reduce energy costs. Modeling: Computer models based on migration behavior inform management strategies and predict seasonal movements. c Case Studies - Oceanodromous Fish

22. Diadromous fish migrate between freshwater and the sea. They constitute a significant portion of the world's commercial fish catch. c Diadromous Fish “Migratory Wonders of the Aquatic World”

23. Definition: Species migrating from sea to freshwater to spawn. Examples: Salmon, lampreys, sturgeons. Life Cycle: Spawning in headwater streams or rivers, young spend time in freshwater before migrating to sea. c Anadromous Fish

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25. Definition: Species migrating from freshwater to sea to spawn. Examples: Eels, mullets, barramundi. Life Cycle: Spawn in sea, larvae drift in ocean currents, mature in freshwater rivers, migrate back to sea to spawn. c Catadromous Fish

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27. Definition: Species spawning in freshwater, offspring move to sea before returning to freshwater to mature and spawn. Examples: Galaxiidae , Clupeidae . Geographic Distribution: Common in regions with varying sea and freshwater productivity. c Amphidromous Fish

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29. c Techniques for Understanding Fish Migration Enhancing Conservation and Management Efforts

30. Historical background: Tagging methods used since the 17 th century. Purpose: Tracking fish movements, understanding migration patterns, and stock identity. c Traditional Techniques: Tagging

31. Advancements in understanding fish movements. Types: Radio and acoustic tags. Data retrieval: Radio or satellite transmission. Simultaneous monitoring of multiple fish over entire migrations. c Advanced Techniques: Electronic Tags

32. Concentration in Specific Areas: Migrating fish follow well-established routes at specific times, making them more concentrated in certain areas. This concentration makes them easier targets for fisheries. Targeting Diadromous Fish: Diadromous fish, which migrate between freshwater and marine environments, are often targeted by fisheries as they pass through narrow points like river mouths. Economic Value of Small Migratory Fish: Small migratory fish, such as some amphidromous species, have economic value mainly during their migration due to their concentration in time and space. c Migration and Exploitation

33. Examples of Targeted Species: Goby Larvae: Fisheries target migrating larvae of various goby species in regions like the Philippines, Tahiti, and the Caribbean. Galaxiids: Fisheries target galaxiids in locations such as Australia, New Zealand, and Chile during migration. Glass-Eels: Catadromous fish like glass-eels are harvested when concentrated, often at river mouths or estuaries. For example, the elver fishery in the River Severn, England, targets these juvenile stages. Significance: Understanding the migration patterns of fish is essential for fisheries management and sustainable exploitation of fish stocks. c

34. Fish migration is vital for ecosystems and human activities like fishing. Understanding its physiology and behavior is crucial for effective management and conservation. Factors like light, temperature, and water currents influence migration patterns. Exploitation by fisheries relies on predictability, but management must consider ecological importance. Tagging advancements offer insights into movements and behavior. Further research and technology will aid conservation. Fish migration involves various disciplines and highlights the interconnectedness of aquatic ecosystems, emphasizing the need to preserve natural behaviors for environmental health. c Conclusion

35. Ballantyne, J. S., & Robinson, J. W. (2011). Physiological Specializations of Different Fish Groups (Chondrichthyes): Physiology of Sharks.  Skates and Rays Elsevier Inc. of Guelph Canada ,  8 , 7-1818. Sullivan, M. G. (2004). Handbook of Fish Biology and Fisheries. Volume 1: Fish Biology. Volume 2: Fisheries. Ueda, H. (2011). Physiological mechanism of homing migration in Pacific salmon from behavioral to molecular biological approaches.  General and Comparative Endocrinology ,  170 (2), 222-232. Ueda, H., & Tsukamoto, K. (Eds.). (2013).  Physiology and ecology of fish migration . CRC Press. c References

36. c Thank You !!