Reef-friendly tips

Protecting the Reef Begins with Everyday Choices

No matter where you live, your choices can still impact coral reefs

  • Most sunblocks actually contain chemicals that kill corals!

    Is your sunblock reef-safe? Look at the list of Active Ingredients to find out:

    Reef-safe ingredients: Non-nano Zinc Oxide, and Non-nano Titanium Oxide

    Unsafe ingredients: Oxybenzone, Avobenzone, Avobenzine, Octinoxate, Ethylhexyl Methoxycinnamate, Homosalate, Octisalate, and Octocrylene

    Reef-safe sunblock may even be safer for us humans too, so it’s a good option to use for any outdoor activities, even if you don’t plan to explore the reef.

    Check out our “Reef-Safe Sunblock Guide” below to learn more!

    Sources: National Park Service and NOAA

  • It can kill sea creatures and coral!

    Marine animals can eat and get tangled in debris. Even litter far away from the ocean can easily make its way down to the coast through rivers, streams, and wind, so it’s important to never leave any trash behind. When visiting the beach or going on outdoor adventures, remember to “pack it in, pack it out” and “leave no trace!”

    The oceans of the world are all connected by currents, so ocean trash from one part of the world can easily drift over to Guam and other coral reef habitats. Make sure not to leave any trash behind, no matter where you live in the world.

  • They belong in the ocean where they are home to many sea creatures!

    Corals and shells sold in stores are usually taken from the wild. By refusing to purchase these items, you help to keep these natural resources in the wild where they can continue to provide shelter for other animals.

  • The less we use, the less will get into the ocean where it can harm marine life.

    Plastics are a huge threat to coral reefs and can take hundreds, even thousands, of years to degrade and decompose. Even with our best efforts to properly dispose of waste, plastic can still get into the ocean and cause problems for marine life. You can be a part of the solution by starting at the source and reducing the amount of plastic you use!

    For example:

    • Use a reusable water bottle instead of buying plastic bottles

    • Use reusable grocery bags instead of plastic bags

    • Carry reusable utensils and straws with you and refuse plastic ones

    • Buy pasta and other food items that come in recyclable cardboard boxes or glass jars instead of plastic packages

    • Use reusable snack bags and food containers instead of disposable ones

  • In general, it’s better for the local economy and the environment.

    Buying local seafood supports local fishers and also reduces the environmental impact of importing seafood from other places.

    Another alternative is to catch your own seafood using sustainable practices! Scroll down to the ‘Fair Fishing’ section to learn more about reef-friendly fishing methods and local fishing rules.

    Even if you don’t live near the ocean, the seafood you eat may have come from a reef! Choose your seafood wisely to avoid contributing to overfishing on coral reefs.

A sandy beach with turquoise water, blue sky, and buildings in the background

Vibrant green hillside with the ocean in the background

Ridge to Reef

Photo by Guam DoAg Forestry

Everything is connected; what we do on land affects our seas

Trash, pollution, pesticides, and sediment find their way into the ocean from the tops of the mountains (Ridge) through rivers and streams all the way down to the ocean (Reef). Help protect the reef by caring for our land!

    • Fires kill large areas of vegetation, freeing up sediment (dust and dirt particles) to be carried into our streams, rivers, and coastal waters whenever it rains. Lots of sediment flowing into the ocean smothers corals, leading to sickness and even death.

    • 100% of Guam’s wildfires are started by humans. To prevent wildfires, avoid burning household trash, or only do so when you can closely monitor the fire and put it out if the weather becomes windy. Discarded cigarettes can also start wildfires, so always make sure to put out the embers and dispose of them in a trash can instead of tossing them on the ground.

    • Driving off-road tears up vegetation and can transform upland areas into badlands: a kind of terrain with little to no plant growth. With no plant roots to anchor the sediment, it flows freely onto nearby reefs and causes problems for the corals.

    • The best way to prevent this damage is by stopping off-roading altogether. An alternative is to avoid off-roading after heavy rains or when the soil is especially muddy.

    • Native plants are best suited to grow here in Guam and contribute to the ecosystem. Their roots will stabilize the hillside, reducing the amount of sediment that flows from upland areas down to the ocean during rain storms. Native plants also help provide habitats for native species.

    • Rain gardens help to catch rainwater and prevent it from flowing freely into the ocean. This reduces the amount of pollution and sediment that gets onto our coral reefs. A rain garden is also a great way to grow your own fruits and veggies!

      • Follow Guam DoAg Agriculture Development Services (ADS) on Instagram for tips on growing your own garden: @doag.adsguam

    • On Guam, we have two invasive feral ungulates (hoofed mammals): the Philippine deer (Rusa marianna), and the feral pig. Both of these species constantly graze on native plants, which reduces plant cover in upland areas and contributes to sediment runoff when it rains.

    • You can help to control invasive deer and pigs by participating in annual hunting derbies hosted by the Guam Department of Agriculture.

    • If you don’t live in Guam, support your own community’s local efforts to cull invasive species on land and at sea.

    • Dumping trash on the ground, throwing out household wastewater and chemicals, and dumping animal manure are practices that will harm environments on land and at sea. All of these materials and substances can be easily carried into the ocean, where they can damage corals and cause bleaching.

    • Tips for reducing your pollution:

      • Make sure to dispose of all trash in a dumpster.

      • Reduce your use of pesticides, and replace household chemicals with water-based products whenever possible to reduce the chances of these chemicals ending up on the reef.

      • Clean up all pet feces and dispose of manure in the landfill or in compost facilities.

      • Never dump used oil or other chemicals down the storm drain where they will flow to the ocean, but dispose of them in hazardous waste facilities.

Take nothing but pictures

Leave nothing but bubbles

Kill nothing but time

Follow All Marine Preserve Rules

Guam has five marine preserves, which are areas where fishing and harvesting are restricted so that marine species can thrive. Think of these preserves as “safe zones” for fish, corals, and other marine life! These safe zones help to ensure that healthy habitats and healthy populations of marine species will be around for future generations to enjoy.

Each marine preserve has its own specific laws about which activities are allowed, so please make sure to familiarize yourself with these laws before visiting a marine preserve.

    • Engage in spearfishing or any other form of fishing unless otherwise specified

    • Harm or chase marine life

    • Take sea cucumbers, crabs, snails, coral (alive or dead), or other marine life

    • Take sand, shells, rocks, seagrass, mangroves, or other natural materials

Map of Guam's Marine Preserves

Click here for more information on local marine preserves and laws:

Beach Guidance

  • Strikethrough icon of snorkel fins brushing coral

    Don't step on the coral

    Corals are living animals! They are fragile and can die when walked on or touched. Make sure to only stand on the sand, not coral, if you need a rest while snorkeling.

  • Strikethrough icon with a hand feeding bread to fish

    Don't feed the fish

    Feeding fish can make them sick and can disrupt the food web since they aren’t eating the things they naturally would. It also can make fish more aggressive and overly reliant on humans, reducing their ability to feed themselves.

  • Strikethrough icon with a hand touching a turtle

    Look, but don't touch

    Harassing reef species stresses them out. Touching them, chasing them, or blocking their path can be dangerous for the animal and for you, so keep a safe distance and admire them from afar.

  • Strikethrough icon with a hand reaching for a seashell

    Leave shells, coral, and dead species on the beach

    Dead marine species are an important part of the ecosystem as a food source for scavengers. Empty shells and dead corals can also provide shelter for other animals, so it’s best to leave them be.

  • Strikethrough icon with an anchor hitting coral

    Don't anchor on the reef

    Anchors can easily break coral structures that took decades or even centuries to grow. Once a coral is broken, it will die soon after. Anchoring on the sand is always a better option.

  • Use reef-safe sunscreen or wear sun protection

    Using reef-safe sunscreen protects corals from the toxic chemicals found in most sunscreens. Wearing a long-sleeve rashguard or other sun protection is another great reef-friendly option!

  • Strikethrough icon with a jetski hitting coral

    Avoid coral and sea grass when jet-skiing

    Jet-skiing is very loud underwater and can disturb the marine life that inhabits coral reefs and seagrass beds. They also can hit corals in shallow water, causing damage to the ecosystem and the jet ski.

  • Give wild mammals space

    It is illegal to chase, touch, or harass wild marine mammals. When dolphin-watching, you must stay at least 50 meters away and do not try to block their path, separate one from the group, feed them, or touch them.

  • Don't litter

    Trash in the ocean is an eye-sore and puts marine life at risk of entanglement. Some sea creatures may even mistake floating debris for food and fill their bellies with harmful undigestible debris. Let’s all keep our oceans and beaches trash-free!

  • Strikethrough icon with snorkel fins stirring the sand seafloor

    Avoid stirring up the sand

    Stirring up the sand with your fins can make the water cloudy and kick up sand particles onto the corals, which can prevent their access to sunlight. It can also disturb creatures who live in the sand.

Learn 3 easy steps to protect Guam’s coral reefs when enjoying the water. Video produced by former GCRI Coral Fellow, Mallory Morgan.

Dangerous Marine Life

For your own safety, please be aware of your surroundings and avoid contact with the following species. In the instance of a sting or bite, remain calm and call 911.

  • Barracuda

  • Box jellyfish

  • Crown-of-thorns sea star

  • Moray eel

  • Black-tip reef shark

  • Fire coral

  • Lionfish

  • Hammerhead shark

  • Portuguese man-of-war jellyfish

  • Sea urchin

  • Cone snail

  • Stingray

  • Stonefish

  • Bristleworm

Ocean Safety Tips

Look for posted signs of hazards or warning flags on the lifeguard towers. Do not swim if the red flag is up.

Use a lifejacket or floatation device

Always swim with a buddy

Rip Current Safety

If you feel caught in a strong current or undertow, do not panic and do not swim against it. Instead, swim parallel to the shore, then swim back to shore once you are out of the current.

Watch this video on rip current safety or click the button below to learn more:

Other Ways to Help

Report Coral Threats

Want to know how you can help protect the reef? Let us know what you see! We want to know if our reefs look sick, damaged, or tangled up in marine debris. It’s also very important to report sightings of coral bleaching and Crown-of-Thorns sea stars (COTS) because early detection helps us take action as soon as possible. Report sightings and observations of coral reef threats to the Eyes of the Reef Marianas program by clicking the blue button below!

Spiky crown-of-thorns sea star on a rocky substrate underwater

Crown-of-Thorns sea star, Acanthaster cf. solaris

White, bleached coral underwater

A thicket of Staghorn Acropora pulchra bleaching on the western reef flat by Adelup in 2016

Report Violations

If you see someone violating marine preserve rules or other environmental laws, call the TOKA hotline! This hotline alerts Conservation Law Enforcement to the issue so that they can keep our reefs safe.

TOKA informational graphic with the TOKA hotline: 671-864-8652

    • Fishing in a no-take marine preserve

    • Illegal dumping

    • SCUBA spearfishing

    • Using explosives or poison to capture fish

    • Removing or relocating live coral

Report Seagrass Observations

Seagrass flowers in Guam are quite mysterious and scientists aren't sure when, where, and how often they produce flowers. Please help us keep an eye out and let us know if you notice any seagrass flowers in the water. Seagrass is a flowering plant but its flowers don’t look like what you might expect, so refer to this guide to help you know what to look for!

Seagrass informational flyer with photos of flowering seagrass

Practice Fair Fishing

Fish are an important part of the coral reef ecosystem. Each species has a unique role: some graze on algae that would otherwise smother corals, others are apex predators who keep prey populations in check, and some even help other fish stay clean by picking away the parasites on their skin. When one species is overfished, it can affect the entire ecosystem

Fishing fairly is all about taking extra measures to ensure that we don’t take more than our fair share from the reef. This will not only help to keep Guam’s reef ecosystems healthy but also means that there will be more fish around for future generations of fishers.

Here are some suggested practices for fair fishing:

  • Measure your catch to see if it meets the minimum recommended length (a.k.a. “L50”) and consider tossing the fish back if it doesn’t meet the minimum

  • Only take what you need

  • Follow fishing rules for marine preserves

  • Make sure nets or other gear are not left behind

  • Do not drop your anchor in reef areas because it kills the coral! Use mooring buoys or drop anchor in sandy areas instead

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