Is the Manufacturing of a COVID-19 Vaccine a Threat to Shark Conservation?

Question: Today’s question is a composite. A general fervor has broken out online about a recent petition that claims half a million sharks will be killed to harvest squalene for a COVID vaccine. For example:

To address these concerns, this edition of Ask A Marine Biologist tackles the following question: I saw a petition claiming that creating a COVID-19 vaccine will kill lots of sharks, is this a real shark conservation concern?

Answer: While squalene made from shark liver oil is indeed sometimes used in vaccines, recent claims that this represents a major shark conservation issue are at best oversimplified, and at worst fear-mongering that distracts from real issues.

According to a recent analysis published as a preprint (which means not yet peer reviewed), available here, and an FAQ about it written by the author here, yes, squalene is often used as an adjuvant, which means a chemical in a vaccine that makes it work more effectively. And yes, some squalene is made from shark liver oil. But no, this doesn’t mean we’re especially likely to see large-scale shark slaughter to fulfill demand for squalene for COVID-19 vaccines.

In terms of conservation, it matters which sharks would be killed, not how many. Killing 500,000 spiny dogfish would amount to a rounding error, while killing 500,000 daggernose sharks would be an extinction-level event. The biggest conservation concern raised by the recently published Macdonald and Soll analysis is that deep-sea sharks have more liver oil but are also more vulnerable to overfishing pressure. Ramping up fisheries for deep-sea sharks would indeed be a problem, but currently there’s no evidence that this is happening.

It’s also important to note here that using shark liver oil to make vaccines does not necessarily equate to the death of many more sharks that wouldn’t have been killed otherwise. As paper author Catherine Macdonald points out in her FAQ, about 100 million sharks are caught each year in existing fisheries, and we could get lots of squalene from those. Perhaps most importantly, you can get squalene of the same pharmaceutical quality for just about the same cost from plants. It just takes a little longer, so we should get started now. The authors stress that this absolutely doesn’t mean that sharks are more important than humans in a public health crisis; it means we can protect biodiversity while also saving human lives if we plan ahead a little.

It’s worth paying attention to this, but there’s no reason to panic.

This is a pretty good case study of how exaggerating or misrepresenting the data leads to panic without actually solving anything. In general, you should probably be pretty skeptical of online conservation petitions created by a person or group you’ve never heard of — online petition platforms make it easy for anyone to make these petitions, even by people who might be misinformed themselves.

AUTHOR’S NOTE: Dr. Catherine Macdonald and Dr. Shiffman are former graduate school classmates and have collaborated on some unrelated projects. He was not involved in her analysis of shark liver oil and COVID-19 vaccines.

Ask a Marine Biologist is a monthly column where Dr. David Shiffman answers your questions about the underwater world. Topics are chosen from reader-submitted queries as well as data from common internet searches. If you have a question you’d like answered in a future Ask a Marine Biologist column, or if you have a question about the answer given in this column, email Shiffman at WhySharksMatter@gmail.com with subject line “Ask a marine biologist.”

Dr. David Shiffman is a marine conservation biologist specializing in the ecology and conservation of sharks. An award-winning public science educator, David has spoken to thousands of people around the world about marine biology and conservation and has bylines with the Washington Post, Scientific American, New Scientist, Gizmodo and more. Follow him on Twitter, Facebook and Instagram, where he’s always happy to answer any questions about sharks.

The views expressed in this article are those of David Shiffman, and not necessarily the views of Sport Diver or Scuba Diving magazines.