Losing sharks can disrupt coastal food webs that billions of people depend on for food. When food chains lose their top predators, the rest can unravel as smaller prey species multiply.
In my years of talking with the public about sharks and ocean conservation, I’ve found that many people care about sharks and want to help but don’t know how. The solutions can be quite technical, and it’s challenging to understand and appreciate the scale and scope of some of the threats.
At the same time, there is an enormous amount of oversimplification and even misinformation about these important topics, which can lead well-intentioned people to support policies that experts know won’t work.
A 2020 study that surveyed 371 reefs found that sharks had virtually disappeared from about 20% of them.
Don’t eat unsustainable seafood
The No. 1 threat to sharks and rays — and arguably, to marine biodiversity in general — is unsustainable overfishing. Some fishing methods are incredibly destructive to marine life and habitats.
They can also produce high rates of bycatch — the unintended catch of nontarget species. For example, fishermen pursuing tuna may accidentally catch sea turtles or sharks swimming near the tuna.
The single most effective thing that individual consumers can do is to avoid seafood produced using these harmful methods. This does not mean completely avoiding seafood, as some advocates urge. Seafood is healthy, delicious and culturally important, and there are environmentally friendly ways of catching it sustainably. There are even sustainable fisheries for sharks.
Reputable organizations such as California’s Monterey Bay Aquarium publish sustainable seafood guides that rate different types of seafood based on how they are caught or raised. While experts may quibble over details of some of these rankings, consumers can follow these guidelines and know that they are helping to protect sharks and ocean life in general.
Support reputable environmental nonprofits, not harmful extremists
Lots of great environmental nonprofit organizations work on shark issues and offer opportunities to get involved, such as donating money and communicating with elected officials and other decision-makers. In my book, I describe the work of many of these groups, including my favorite, Shark Advocates International.
Unfortunately, some organizations promote pseudoscience that doesn’t help anyone or anything. In a 2021 study, colleagues and I surveyed employees of 78 nonprofits that work on shark conservation issues to understand whether and how these organizations engaged with the science of shark conservation.
We found that a small but vocal minority had never read scientific reports or spoken with scientists, and held blatantly incorrect and harmful views that cannot help sharks. For example, some organizations are trying to get certain airlines to stop carrying shark products like dried fins, without acknowledging that well over 95% of fins are shipped by sea or that sustainable sources of these fins exist.
One of my particular pet peeves is amateur online petitions that may not reflect actual conditions. For example, in the spring of 2022, some 60,000 people signed a petition calling for Florida to ban the practice of shark finning — without recognizing that Florida had banned shark finning in the early 1990s. As I explain in my book, it is essential to identify organizations that use science in support of worthwhile conservation goals and avoid promoting others that do not.
Look to experts
Many ocean science, management and conservation experts are active on social media. Following them is a great way to learn about fascinating new scientific discoveries and conservation issues.
Unfortunately, sharks also get a lot of sensational coverage in the media, and well-intentioned but uninformed people often spread misinformation on social media. For example, you may have seen posts celebrating Hawaii for banning shark fishing in its waters — but these posts don’t note that about 99% of fishing in Hawaii occurs in federal waters.
Don’t take the bait. By getting your information from reliable sources, you can help other people learn more about these fascinating, ecologically important animals, why they need humans’ help and the most effective steps to take.
David Shiffman does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
This article is republished from The Conversation under a Creative Commons license.
Scientists figure out how vampire bats got a taste for blood
kajornyot wildlife photography // Shutterstock
We owe a lot of our health and happiness to some of the most undeservedly reviled creatures in nature. Bats, in particular, get a bad rep as blood-sucking, horror-genre caricatures or Halloween mascots at best, and disease-spreading enemies of humanity to be culled at worst. Without them, we would not have tequila, bananas, or cacao. Without them, there would be ecosystem collapse.
It may sound like a dramatic proclamation, but nature is constantly working to stay balanced, with every living thing doing its part to maintain homeostasis simply by existing in its given ecosystem. By introducing or removing a variable, the balance often shifts with severe consequences. This is why invasive species are so devastating.
Several studies suggest humans are born with an innate, evolutionary stress response to animals that posed significant threats to our ancestors. Researchers also point out this stress response does not necessarily equate to fear but rather intense focus. We’ve evolved to be hyperaware of threats like snakes and spiders because it’s kept us alive. Today, it’s not just avoiding snakes that keeps us alive and healthy. One snake species, the Brazilian pit viper, is a vital source of the live-saving ACE inhibitor class of medicine.
If we aren’t born with the fear that makes us vilify certain species, then we are learning it, from a young age and from our observations of others. Culture can also be the reason why one person reveres the wolf while another views it only as a voracious predator. Consider the formative childhood fairy tales passed down through generations like Little Red Riding Hood (both the Brothers Grimm and Charles Perrault versions) or The Three Little Pigs: at their center are lessons to be heeded about danger and death in the form of a wolf.
Fear and misunderstanding have led to the culling of many species, sometimes to the brink of extinction and to subvert conservation efforts. But knowledge can conquer fear. To help, Stacker compiled a list of 10 animals often misjudged and misunderstood by humans. Keep reading to learn the role these 10 misunderstood animals play in the ecosystem.
We owe a lot of our health and happiness to some of the most undeservedly reviled creatures in nature. Bats, in particular, get a bad rep as blood-sucking, horror-genre caricatures or Halloween mascots at best, and disease-spreading enemies of humanity to be culled at worst. Without them, we would not have tequila, bananas, or cacao. Without them, there would be ecosystem collapse.
It may sound like a dramatic proclamation, but nature is constantly working to stay balanced, with every living thing doing its part to maintain homeostasis simply by existing in its given ecosystem. By introducing or removing a variable, the balance often shifts with severe consequences. This is why invasive species are so devastating.
Several studies suggest humans are born with an innate, evolutionary stress response to animals that posed significant threats to our ancestors. Researchers also point out this stress response does not necessarily equate to fear but rather intense focus. We’ve evolved to be hyperaware of threats like snakes and spiders because it’s kept us alive. Today, it’s not just avoiding snakes that keeps us alive and healthy. One snake species, the Brazilian pit viper, is a vital source of the live-saving ACE inhibitor class of medicine.
If we aren’t born with the fear that makes us vilify certain species, then we are learning it, from a young age and from our observations of others. Culture can also be the reason why one person reveres the wolf while another views it only as a voracious predator. Consider the formative childhood fairy tales passed down through generations like Little Red Riding Hood (both the Brothers Grimm and Charles Perrault versions) or The Three Little Pigs: at their center are lessons to be heeded about danger and death in the form of a wolf.
Fear and misunderstanding have led to the culling of many species, sometimes to the brink of extinction and to subvert conservation efforts. But knowledge can conquer fear. To help, Stacker compiled a list of 10 animals often misjudged and misunderstood by humans. Keep reading to learn the role these 10 misunderstood animals play in the ecosystem.
Scientists figure out how vampire bats got a taste for blood
subphoto.com // Shutterstock
The world needs bats. Not only are they pollinators and pest-reducers, one study found that bats, by routinely feeding on insects, saved the U.S. agricultural industry roughly $23 million annually on pesticides. Bats have evolved to be effective vector species, or carriers and transmitters of deadly diseases like Ebola, Marburg, and SARs. This adaptation, especially in the midst of the coronavirus pandemic, has drawn the persecution of bats from communities around the world to the detriment of the larger ecosystem.
subphoto.com // Shutterstock
The world needs bats. Not only are they pollinators and pest-reducers, one study found that bats, by routinely feeding on insects, saved the U.S. agricultural industry roughly $23 million annually on pesticides. Bats have evolved to be effective vector species, or carriers and transmitters of deadly diseases like Ebola, Marburg, and SARs. This adaptation, especially in the midst of the coronavirus pandemic, has drawn the persecution of bats from communities around the world to the detriment of the larger ecosystem.
Scientists figure out how vampire bats got a taste for blood
Ramon Carretero // Shutterstock
Sharks are an integral part of the marine food web and are vital to the health of ecosystems the world over, from coral reef ecosystems in Australia to coastal U.S. fisheries. In 2004, after decades of overfishing, the population of large sharks off the east coast of the U.S. fell by 75%. As a result, the ray population exploded, and the scallop population—a delicacy for rays—was decimated along with scallop fisheries off the coast of North Carolina. Sharks can also impact the future of human medicine. Shark DNA, fully sequenced in 2019, may hold clues about how to better understand, treat, or even cure cancer and Alzheimer's disease, and more quickly and efficiently heal wounds.
Ramon Carretero // Shutterstock
Sharks are an integral part of the marine food web and are vital to the health of ecosystems the world over, from coral reef ecosystems in Australia to coastal U.S. fisheries. In 2004, after decades of overfishing, the population of large sharks off the east coast of the U.S. fell by 75%. As a result, the ray population exploded, and the scallop population—a delicacy for rays—was decimated along with scallop fisheries off the coast of North Carolina. Sharks can also impact the future of human medicine. Shark DNA, fully sequenced in 2019, may hold clues about how to better understand, treat, or even cure cancer and Alzheimer's disease, and more quickly and efficiently heal wounds.
Scientists figure out how vampire bats got a taste for blood
Kwadrat // Shutterstock
According to researchers, pumas, or mountain lions, are not just moderators good at keeping other populations of the food web in check—they are ecosystem engineers. As largely—but not exclusively—solitary carnivores, a puma’s kill can feed much more than just itself. The carrion of an elk can feed other apex predators such as bears and attract scavengers and decomposers like beetles, which provide the important service of breaking down decaying organic matter. Why should you care if pumas provide food for beetles? Because healthy beetle populations create fertile soil, pollinate flowers, and eat insects that feed on our crops.
Puma encounters in settled areas are not the result of rogue predators with new appetites. Pumas are losing their habitat to real estate development. Since 1990, roughly 60% of new single-family homes in the U.S. have been built in puma-inhabited territory. But the bigger issue is our existence and settlement in these areas are attracting deer, a puma’s primary source of food. The more human activity attracts prey, the more we should expect to encounter pumas doing what they are biologically driven to do—survive.
Kwadrat // Shutterstock
According to researchers, pumas, or mountain lions, are not just moderators good at keeping other populations of the food web in check—they are ecosystem engineers. As largely—but not exclusively—solitary carnivores, a puma’s kill can feed much more than just itself. The carrion of an elk can feed other apex predators such as bears and attract scavengers and decomposers like beetles, which provide the important service of breaking down decaying organic matter. Why should you care if pumas provide food for beetles? Because healthy beetle populations create fertile soil, pollinate flowers, and eat insects that feed on our crops.
Puma encounters in settled areas are not the result of rogue predators with new appetites. Pumas are losing their habitat to real estate development. Since 1990, roughly 60% of new single-family homes in the U.S. have been built in puma-inhabited territory. But the bigger issue is our existence and settlement in these areas are attracting deer, a puma’s primary source of food. The more human activity attracts prey, the more we should expect to encounter pumas doing what they are biologically driven to do—survive.
Scientists figure out how vampire bats got a taste for blood
halimqd // Shutterstock
Snakes are both predator and prey, which makes them a vital part of the food web. If snakes were to disappear from the earth tomorrow, we would see an explosion of rats and mice—their primary food source— and a rapid spread of zoonotic diseases that rodents harbor, like Lyme disease and even bubonic plague. A single pair of rats can generate over 1 million descendants in just a year and a half. And if you are one of the millions of Americans taking an ACE inhibitor to treat cardiovascular disease, high blood pressure, diabetes, or migraines, you may want to thank the next Bothrops jararaca or Jararaca pit viper you see. In 1981, peptides in their venom were used to make Captopril, the first ACE inhibitor.
halimqd // Shutterstock
Snakes are both predator and prey, which makes them a vital part of the food web. If snakes were to disappear from the earth tomorrow, we would see an explosion of rats and mice—their primary food source— and a rapid spread of zoonotic diseases that rodents harbor, like Lyme disease and even bubonic plague. A single pair of rats can generate over 1 million descendants in just a year and a half. And if you are one of the millions of Americans taking an ACE inhibitor to treat cardiovascular disease, high blood pressure, diabetes, or migraines, you may want to thank the next Bothrops jararaca or Jararaca pit viper you see. In 1981, peptides in their venom were used to make Captopril, the first ACE inhibitor.
Scientists figure out how vampire bats got a taste for blood
Natursports // Shutterstock
Spiders are dutiful mothers, skillful engineers, and friends to all humans, whether humans want to admit it or not. In fact, they’re more than friends—they’re our unknowing protectors. Spiders are pivotal to crop production because they eat the pests that would otherwise devour our food. According to some researchers, humans could, hypothetically, face famine in the complete absence of spiders. In addition to eating pests that eat our food, spiders also eat disease-carrying insects like mosquitos.
Spiders are dutiful mothers, skillful engineers, and friends to all humans, whether humans want to admit it or not. In fact, they’re more than friends—they’re our unknowing protectors. Spiders are pivotal to crop production because they eat the pests that would otherwise devour our food. According to some researchers, humans could, hypothetically, face famine in the complete absence of spiders. In addition to eating pests that eat our food, spiders also eat disease-carrying insects like mosquitos.
Scientists figure out how vampire bats got a taste for blood
Carlos Aranguiz // Shutterstock
Rats are viewed unfairly as the scourge of the animal kingdom. It is true that rats can be pests, can multiply alarmingly fast, and can carry harmful diseases that spread to humans. And you should never come between a rat and its subway pizza slice. But rats fill an important ecological niche as both scavengers and food sources for larger predators. Many people don’t know that rats are also one of the most intelligent species on the planet, and can even outperform humans in some cognitive tests. Several studies suggest that rats can even show the capacity for more complex emotions like empathy and morality. Humans owe a debt of gratitude to rodents for their role in the advancement of life-improving and life-saving scientific research—95% of all lab animals are rats or mice.
Carlos Aranguiz // Shutterstock
Rats are viewed unfairly as the scourge of the animal kingdom. It is true that rats can be pests, can multiply alarmingly fast, and can carry harmful diseases that spread to humans. And you should never come between a rat and its subway pizza slice. But rats fill an important ecological niche as both scavengers and food sources for larger predators. Many people don’t know that rats are also one of the most intelligent species on the planet, and can even outperform humans in some cognitive tests. Several studies suggest that rats can even show the capacity for more complex emotions like empathy and morality. Humans owe a debt of gratitude to rodents for their role in the advancement of life-improving and life-saving scientific research—95% of all lab animals are rats or mice.
Scientists figure out how vampire bats got a taste for blood
Pablo Garcia Saldana // Shutterstock
Coyotes help manage populations of low-tier predators like skunks, raccoons, and foxes. This is especially important to the health and diversity of many bird populations. As North America's oldest indigenous species, they are remarkably successful. The coyote’s ability to adapt—the reason for their longevity—is also the reason for human confrontations. Coyotes have learned to associate urban regions with easy access to food, be it garbage, pet food, or even small pets. Today, as many as 500,000 coyotes are killed each year in concerted efforts by government agencies, hunters, and ranchers.
Pablo Garcia Saldana // Shutterstock
Coyotes help manage populations of low-tier predators like skunks, raccoons, and foxes. This is especially important to the health and diversity of many bird populations. As North America's oldest indigenous species, they are remarkably successful. The coyote’s ability to adapt—the reason for their longevity—is also the reason for human confrontations. Coyotes have learned to associate urban regions with easy access to food, be it garbage, pet food, or even small pets. Today, as many as 500,000 coyotes are killed each year in concerted efforts by government agencies, hunters, and ranchers.
Scientists figure out how vampire bats got a taste for blood
slowmotiongli // Shutterstock
If you have tomato plants that are thriving, you may have a wasp to thank for it. Hornworms, which any gardening enthusiast will recognize as the enemy of tomatoes, just happen to make the perfect meal for young parasitic wasps. Female wasps lay their eggs on hornworm caterpillars and, after the young wasps hatch, they will feed on the host caterpillar. Parasitic wasps have no affinity for the tomato plant itself.
slowmotiongli // Shutterstock
If you have tomato plants that are thriving, you may have a wasp to thank for it. Hornworms, which any gardening enthusiast will recognize as the enemy of tomatoes, just happen to make the perfect meal for young parasitic wasps. Female wasps lay their eggs on hornworm caterpillars and, after the young wasps hatch, they will feed on the host caterpillar. Parasitic wasps have no affinity for the tomato plant itself.
Scientists figure out how vampire bats got a taste for blood
Allison Coffin // Shutterstock
Wolves are keystone species, a species that other species in the food web depend on, so much so that their absence could cause an ecosystem collapse over time. Yellowstone experienced this exact trophic cascade between 1926 and 1995. Everything about the landscape, from the largest animals down to the grass, was impacted by the wolves’ 70-year absence. Reintegration efforts have been ongoing since then, with much of the natural habitat rebounding and rebalancing. In 2020, the gray wolf was removed from the endangered species list after nearly 50 years of federal protection. Gray wolf populations are listed as stable, but debate among experts continues about the nuance of this classification.
Allison Coffin // Shutterstock
Wolves are keystone species, a species that other species in the food web depend on, so much so that their absence could cause an ecosystem collapse over time. Yellowstone experienced this exact trophic cascade between 1926 and 1995. Everything about the landscape, from the largest animals down to the grass, was impacted by the wolves’ 70-year absence. Reintegration efforts have been ongoing since then, with much of the natural habitat rebounding and rebalancing. In 2020, the gray wolf was removed from the endangered species list after nearly 50 years of federal protection. Gray wolf populations are listed as stable, but debate among experts continues about the nuance of this classification.
Scientists figure out how vampire bats got a taste for blood
Holly Kuchera // Shutterstock
Most people go about their lives without thinking very much about opossums. It isn’t until we come across one that we even remember they’re around. They exist, mainly out of sight, doing some very important work that benefits us all. Opossums eat over 90% of disease-harboring ticks, and one opossum can eat up to 5,000 ticks in a season. Because they are resistant to snake venom, these nocturnal mammals also prey on snakes that pose a danger to humans.
Most people go about their lives without thinking very much about opossums. It isn’t until we come across one that we even remember they’re around. They exist, mainly out of sight, doing some very important work that benefits us all. Opossums eat over 90% of disease-harboring ticks, and one opossum can eat up to 5,000 ticks in a season. Because they are resistant to snake venom, these nocturnal mammals also prey on snakes that pose a danger to humans.