Key Threats

Death From Diseases & Predation Tied to Pets, Invasive & Feral Animals

As an island, Hawaiʻi is home to many native, endemic species that are found nowhere else in the world. The human introduction of foreign animals has resulted in unmanaged populations of invasive and feral animals. These invasive species outcompete native species for resources, causing native populations to decline or go extinct. While there are hundreds of different species of invasive plants, insects, and animals, one of the key threats to Hawaiʻi’s marine protected species is the feral cat population.

Feral cats are a direct threat to the ocean through disease and predation. Hawaiʻi’s seabird species are mainly ground nesters, and the unmanaged feral cat population directly predates and kills these seabirds in or near their nests. This is especially a threat for unprotected chicks that haven’t learned to fly yet, and it prevents recovery of threatened seabird populations. Feral cats also transmit a deadly disease called toxoplasmosis. Toxoplasmosis is an infection caused by a parasite that can only reproduce in the gut of cats. Cats spread this parasite island-wide through excrement and it finds its way to the ocean, where it kills marine mammals. Hawaiian monk seals and spinner dolphins die of toxoplasmosis, which is hard to detect until after death and has no cure. Toxoplasmosis is now the leading disease threat to Hawaiian monk seals. Learn more about toxoplasmosis.

Steps You Can Take

• • Ways to Help – The feral cat population is growing with little control or preventative actions. You can make a difference by letting your legislative representatives know more needs to be done about this growing issue before it’s too late. Learn the contact information of your representative.
  • Do not feed cat colonies – Populations of feral cats are supported by community feeding and predation of native animals. Do not feed feral cats so their population doesn’t continue to grow.
  • Keep Your Pet Indoors – Keeping your animals inside will help prevent them from predating native wildlife.
  • Never abandon pet cats – If you are no longer able to care for your pet, please surrender the cat to a local animal shelter so that it has a chance of being adopted, and less of a chance for predating native wildlife.
  • Volunteer with us – HMAR volunteers are able to participate in different programs that best suit their interest to help address key threats. Learn more on our Get Involved webpage

Death & Injury From Human-Caused Trauma (Human Attacks, Boat Strikes, Walking & Driving in Habitat)

Hawaiʻi’s marine protected animals are directly threatened by human-caused trauma, which is serious bodily injury or death. As protected species, these animals are protected by laws and regulations that are enforced with fines and jail time. Regardless, many animals are still dying from intentional harm or killings. The critical habitat needed for survival is also impacted by off-roading vehicles and those walking off trail. Hawaiian monk seals and sea turtles use shorelines to get needed rest, and off-roading vehicles can kill or injure them. Seabirds create underground nests in coastal areas, and both humans and vehicles can easily destroy a nest, and the birds inside, by passing over the nest.

Boat strikes are also a considerable threat to marine animals. The consistent boating and shipping pressure on the marine environment puts marine animals at risk. Air-breathing animals that spend more time at the surface, like the animals HMAR works with, are more vulnerable to this threat. Boat strikes can injure, harm, or kill marine animals.

How Can You Help?

• • Set a spotter – Placing a spotter on the bow of your boat will help identify wildlife and avoid boat strikes. As a spotter, let your captain know if an animal is an area so they can move the vessel before any harm can occur.
  • Shop local – In Hawaiʻi, a large portion of our food and other goods are shipped here from other places. Purchasing local goods that are grown and manufactured here, and thus reducing the need for so many shipments, is better for marine animals and our communities.
  • Stay on marked trails – As a hiker, especially in sanctuaries and protected areas, staying on marked trails means you aren’t at risk of damaging seabird nests.
  • Obey signs and speed limits – Follow warnings about wildlife in the area, such as seabird nests that could be damaged. As a boater, moderate your speed, particularly in channels or when departing or arriving harbors to ensure you can stop or maneuver appropriately when wildlife are spotted in the area.
  • Be aware of your surroundings – Nests and animals can be difficult to notice sometimes. Always look around when you are in Hawaiʻi’s coastal environment to make sure you aren’t at risk of injuring marine animals in the area.
  • Off-road on designated areas – Off-roading on coastlines that are frequented by marine protected species is hazardous to the animals. If you choose to off-road, do so lawfully and in areas that are designated for off-roading vehicles.
  • Spread awareness – Those that intentionally hurt, injure, or kill marine animals are often hard for us to reach as an organization. However, you can be an ocean steward by sharing conservation messages in your community. If our communities are educated on the importance of these native animals and the ocean, it may save animals in the future.
  • Volunteer with us – HMAR volunteers are able to participate in different programs that best suit their interest and help solve key threats. Learn more on our Get Involved webpage

Death From Human-Caused Disease and Pollution

Hawaiʻi’s marine animals are threatened by human-caused disease and pollution in our marine environment. While fishing gear may contribute to marine debris, other marine debris includes any human created waste in our oceans. This can be litter like plastic, Styrofoam, or other materials. Microplastics have already entered the ocean food chain. Marine animals can ingest this marine debris, which can disrupt their nutritional balance, damage their insides, and result in death.

Additionally, human activities have promoted disease in the marine environment. In Hawaiʻi, sea turtles can suffer from Fibropapillomatosis, an infection that causes tumor growth on or in their bodies. Over time, these tumors can impair mobility, vision, the ability to eat, and organ function. Although the cause of infection is not fully understood, it is magnified by excessive nitrate runoff into the marine environment that is associated with human agricultural operations.

Ways to Help

• • • • Reduce your plastic usage – Reducing your single use and overall plastic usage will help prevent more unnatural materials from polluting our oceans. Explore alternatives such as reusable, recyclable, and natural materials.
      • Support clean agriculture – Supporting organic, small-scale agriculture options in your area can make a difference for pollution run-off in our oceans. In Hawaii, harsh chemicals used on land often find their way to the ocean. Contact the legislative representative for your district to share the importance of this issue for our environment.
      • Avoid chemical fertilizers and pesticides at home – Opting for organic options for your home garden can make a big difference for our environment. Choose organic options such as manure, compost, or insecticidal soaps to ensure runoff doesn’t cause harm to our coastal waters.
      • Pack Your Trash – Ensuring that trash created on hikes or out in nature is disposed of responsibly can help minimize pollution.
      • Consider materials – Choosing products made of more sustainable materials, such as bamboo, can help reduce plastic pollution. Support sustainable products, companies, and clean ups in your area.
      • Teach others – Share messaging about Fibropapillomatosis and plastic with your friends, family, and on social media. Teaching others will help raise awareness about the issues.
      • Volunteer with us – HMAR volunteers are able to participate in different programs that best suit their interest and help solve key threats. Learn more on our Get Involved webpage

Nesting, Fledging & Pupping Impacts From Coastal Development

Coastal development is a key threat to Hawaiʻi’s marine protected species because it is reducing the critical habitat needed for survival. Hawaiian monk seals, seabirds, and sea turtles rest and reproduce on coastlines. Sea turtles need shoreline to bask, lay their nests, and to regulate their internal temperature, Hawaiian monk seals stay with their pups for 4-6 weeks to raise them after birth, and spend 1/3 of their lifetime resting on beaches. Seabirds nest and reproduce on coasts, and some species return nightly after spending the day at sea. As cities and shorelines continue to develop, many marine animals will be displaced and face another critical challenge to their survival.

Ways to Help

• • • • • Oppose coastal development – Speaking out against coastal development has the capacity to limit the impacts of large projects. Speak with the legislative representatives in your area to express your concern for Hawaiʻi’s marine life.
        • Support coastline protections – Protected coastlines, such a refuges and sanctuaries, ensure that development cannot impact the natural habitat. Support placing protections on essential regions that promote survival for marine life.
        • Volunteer with us – HMAR volunteers are able to participate in different programs that best suit their interest and help solve key threats. Learn more on our Get Involved webpage

Habitat & Ocean Chemistry Impacts From Climate Change & Sea Level Rise

As an island state, Hawaiʻi is disproportionately affected by sea level rise and the associated impacts of climate change, and we are observing that today. Our coastlines, which are critical habitat for the marine animals we work to preserve, are threatened by rising sea levels. The eroding habitat means less areas for marine life to rest, reproduce, raise young, and stay safe.

Climate change is also having cascading effects on the ocean ecosystem as a whole. Ocean acidification and increasing temperatures is altering the chemistry and balance of our oceans, resulting in impacts we do not fully understand yet. For example, coral reefs may be extinct by the end of the century, and they serve as an essential component to the marine food chain. Additionally, rising temperatures have complex effects, including skewing the sex ratios of sea turtles that can reduce successful reproduction. As our ecosystem continues to lose balance, we will see more long-term impacts of climate change in our lifetimes. These changes to our ocean ecosystem will affect humans.

Ways to Help

• • • • • Commit to action – Committing to lower your individual footprint can make a big difference over time. Educate yourself on the ways to lower your footprint, including your food choices, travel, purchases, and daily actions. Setting an example in your community may inspire others to follow suit.
        • Recognize the reality – The climate crisis is undisputed globally outside of the United States. Recognizing that we will need to face the impacts of climate change within the century is one of the first steps to building resiliency to the challenges we will face.
        • Vote – Supporting and electing government officials that are committed to addressing climate change can ensure proper regulations are implemented before it’s too late. Support bills, laws, and leaders that are prioritizing climate change as a crisis.
        • Volunteer with us – HMAR volunteers are able to participate in different programs that best suit their interest and help solve key threats. Learn more on our Get Involved webpage