Ocean at Home Resource: How Big Was This Squid?
by Ariel Zych, Science Friday
How Big Was This Squid?
Learn how scientists estimate the sizes of squid eaten by large predators using only beaks they leave behind in this data-centered lesson from Science Friday.
Though a bit disgusting, two simple methods are available to marine biologists who want to figure out what an ocean predator has eaten: sample the feces it leaves behind, or explore the predator’s stomach and intestines after it dies. However, there’s a major challenge with these two approaches—squid are digested very easily. When a researcher examines the stomach contents or feces of say, a sperm whale, the only squid evidence remaining are the beaks. The good news is that these undigested beaks can be used to try to infer the species and size of the squid that that they came from. In this activity, you'll use real gut content squid beak data to estimate the number, and mass, of squid consumed by a sperm whale.
Ocean Literacy Principles
This resource addresses Ocean Literacy Principle 5a: "Ocean life ranges in size from the smallest living things, microbes, to the largest animal that has lived on Earth, blue whales" by exploring the size and biodiversity of squid, and 5d: "Ocean biology provides many unique examples of life cycles, adaptations and important relationships among organisms (symbiosis, predator-prey dynamics, and energy transfer) that do not occur on land" by analyzing evidence of ecological interactions between large predators and many species and sizes of squid.
About the Author
Ariel Zych is Science Friday’s education director, and was previously a high school science teacher and scientist.