Why Are Shark Populations Declining?

The objective of my project is to research why shark populations are declining around the world
Michael Wilding
Grade 5

Problem

PROBLEM

 

I really like sharks and other ocean animals.  There are so many species of sharks like: great white sharks, hammerheads, bull sharks, tiger sharks, basking sharks and whale sharks.  There are over 500 species of sharks on Earth but their populations have been decreasing over the years.  There are even sharks that are extinct (ex. Megaladon and Helicoprion) or are in danger of becoming extinct. Is it because of climate change, less food, pollution, battling for territory or hunting/fishing? I would like to research why shark populations are decreasing so that I can find the answer and help protect the sharks.

Method

OBJECTIVE, MATERIALS & METHODOLOGY

Objective: To understand the main reasons behind the decreasing populations of sharks, focusing on the top five endangered species

Materials:

  • Internet access for research
  • Logbook and MS Word for recording information
  • Printer to print information
  • Markers, paper, and trifold for presenting data
  • World map to highlight regions with endangered shark species
  • Scientific books, papers and websites (e.g., National Oceanic and Atmospheric Administration (NOAA), IUCN Red List, Shark Trust, Department of Fisheries and Oceans Canada, National Geographic)
  • A list of the top five endangered shark species (Scalloped Hammerhead, Oceanic Whitetip Shark, Mako Shark, Angelshark, and Sand Tiger Shark)

Methodology

  • Created a list of the top 5 endangered sharks
  • Researched the causes of why they are endangered
  • Charted the causes for each shark
  • Compared causes and created conclusion

Research

WHY ARE SHARK POPULATIONS DECREASING?

HYPOTHESIS

 

If shark populations are decreasing, then it is because of overfishing and hunting because there are many places in the world where sharks are harvested for their food or because of fear of sharks.

I took the top 5 endangered sharks, according to the IUCN, and used the status reports of the IUCN Red List to find out the top reason the species of shark is endangered. The IUCN takes all the research done all around the world by scientists and other researchers and then puts it together in a report about what all the different research has shown for causes of shark populations.  It is the organization that politicians, scientists, decision makers and other organizations use to get information about many different plants and animal species on Earth.  

Then I put all the information into a chart to see what the common top reson for sharks going endangered would be.  

Data

ANALYSIS

 

THREAT TO SHARK POPULATION

 

SHARK SPECIES

Overhunting/ Fishing

Pollution

Climate Change

Habitat Loss

Recreation Activities

SHORTFIN MAKO

(Isurus oxyrinchus)

 

X

 

 

 

 

OCEANIC WHITE TIP SHARK               (Carcharhinus longimanus)

 

X

 

 

 

 

SCALLOPED HAMMERHEAD SHARK

(Sphyrna lewini)

 

X

 

 

 

 

ANGELSHARK

(Squatina squatina)

 

X

 

 

 

X

SAND TIGER SHARK

(Carcharias taurus)

 

X

 

 

 

 

X*majority reason of causes of shark population impacts (over 50% of the time it is the cause according to the IUCN)

Conclusion

 

CONCLUSION

Although climate change, pollution, habitat loss and recreational activities all contribute to the decline in shark populations, my research showed that the number one cause of shark deaths is overhunting/fishing.  We need to protect sharks to keep our oceans balanced as sharks are an important part of the environment.

To protect sharks, we need to make stronger boundaries and laws on fishing and hunting sharks of all kinds.  We need to teach people about their impact on sharks (such as eating sharks) and how it will affect the oceans and the sharks in their area.

Another way to protect sharks is to learn more about them to help with the research the IUCN collects and shares. The more we know about sharks, the better we can know how to protect sharks from threats.

Citations

REFERENCES

International Union for Conservation of Nature (IUCN). (January 2025). The IUCN Red List of Threatened Species. https://www.iucnredlist.org/

IUCN reports for the sharks in my project:

 

World Wildlife Fund. (January 2025). Species: Shark. https://www.worldwildlife.org/species/shark .

Shark Trust. (January 2025). Shark Threats. https://www.sharktrust.org/shark-threats .

Skerry, Brian. (2018). The Ultimate Book of Sharks: Your Guide to these Fierce and Fantastic Fish. National Geographic Partners.

National Geographic Kids. (2023). Weird But True! Sharks. National Geographic Partners.

(May/June 2024). Canadian Geographic Magazine: Shark. Volume 144 Number 3.

Government of Canada. Department of Fisheries and Oceans. (January 2025). Shark Research.  https://www.dfo-mpo.gc.ca/species-especes/sharks/index-eng.html

Smithsonian National Museum of Natural History. (January 2025). Sharks. https://ocean.si.edu/ocean-life/sharks-rays/sharks .

OCEARCH. (January 2025). OCEARCH Global Shark Tracker. https://www.ocearch.org/tracker/ .

Saving the Blue. (January 2025). Shark Research FAQs. https://www.savingtheblue.org/faqresearch .

Fahlo. (January 2025). Save the Sharks Tracking. https://myfahlo.com/en-ca/pages/save-the-sharks .

Acknowledgement

ACKNOWLEDGEMENTS

Thank you to my sister, mom and dad for encouraging me.  Thank you to the International Union for Conservation of Nature (IUCN) for providing me with the information and data for my project and thank you for all the work all the researchers and scientists do to help protect animals and plants on Earth.  Thank you to the authors of my favourite shark books for helping me with my interest in sharks.  Thank you to my teachers and Guardian Angel school for having the science fair and helping me.  And thank you to the judges for listening to my project.