1. How might climate change and ocean acidification affect shark populations and their prey?

Climate change and ocean acidification can have several impacts on shark populations and their prey:

• Prey species: Changes in ocean temperature and chemistry can alter the distribution, abundance, and behavior of shark prey species, such as fish, squid, and crustaceans. For example:
  • Warmer waters can lead to changes in the distribution of fish species, making it difficult for sharks to find their preferred prey.
  • Ocean acidification can affect the growth rates and survival of some fish species, potentially reducing the availability of prey for sharks.
• Shark populations: Climate change can directly impact shark populations through:
  • Changes in water temperature and chemistry: Some shark species may be sensitive to changes in ocean conditions, which can affect their physiological processes, such as metabolism, growth, and reproduction.
  • Shifts in habitat: As water temperatures change, sharks may need to move to different areas to find suitable habitats, which can lead to changes in their distribution and abundance.
  • Increased mortality: Climate-related events like coral bleaching, ocean warming, or acidification can increase mortality rates among sharks, particularly in vulnerable species.

2. What are the potential impacts of rising sea temperatures on the distribution of shark species?

Rising sea temperatures can lead to changes in the distribution of shark species:

• Range shifts: As water temperatures warm, some shark species may move poleward (toward the poles) or upward (to deeper waters) to find cooler temperatures.
• Changes in migration patterns: Climate-driven changes in ocean currents and temperature gradients may alter the migration patterns of sharks, potentially leading to changes in their distribution and abundance.
• Local extirpations: As temperatures increase, some shark species may become locally extinct in areas that were previously suitable for them, leading to range contractions.
• Invasive species: Changes in temperature and other environmental conditions can facilitate the spread of invasive shark species into new areas.

Some specific examples of how climate change is affecting shark distributions include:

• Great white sharks (Carcharodon carcharias) are shifting their range northward in response to warming waters.
• Tiger sharks (Galeocerdo cuvier) are moving poleward into Australian waters as a result of climate-driven changes in their prey distribution.
• Hammerhead sharks (Sphyrna spp.) are experiencing local extirpations in some regions due to warming waters.