If you’ve ever come across bright pink egg clusters in your garden or near water features, they might look oddly pretty—almost like nature’s decorations. But don’t let their vibrant color fool you. These seemingly harmless clumps are the eggs of the invasive apple snail, a species that poses a real danger to local environments. While they may catch your eye, they’re far from innocent. In fact, these snails are rapidly becoming one of the most destructive invasive species in the world, and understanding them is crucial to protecting your home and garden.

Apple snails originally hail from South America, but they’ve spread far beyond their native lands. They’ve been introduced—intentionally and unintentionally—into ecosystems around the globe, where they’ve caused major damage to native plants, crops, and aquatic habitats. Their ability to adapt, reproduce quickly, and outcompete native species has made them a growing concern in countries like the United States, where local biodiversity is under constant threat.

Interestingly, apple snails are actually quite popular in aquariums. Certain types, such as Pomacea bridgesii and Pomacea diffusa, are favored because they typically don’t eat live aquatic plants, which makes them less of a nuisance in a controlled tank environment. Their appearance also adds to their appeal—they can be striking in color and impressive in size. Some apple snails can grow as large as six inches, about the size of a baseball or a human fist, making them among the largest freshwater snails on Earth.

Their shells come in a variety of colors and patterns—brown, yellow, albino, blue, even purple and jade—with some displaying beautifully banded shells. Commonly referred to as mystery snails or spike-topped apple snails, these creatures can be fascinating to observe in captivity. But in the wild, some of these same species become serious pests. In several parts of the world, they’re even eaten as a delicacy, though not without consequences.

The major problem with apple snails is how invasive they are. They’ve earned a spot on the list of the world’s 100 worst invasive species. They thrive in wet environments like lakes, swamps, rice paddies, and even garden ponds. As global temperatures rise, these snails are finding it easier to expand their territory, and their ability to survive on land for short periods helps them spread even faster. Equipped with a hard operculum, or “lid,” they can seal their shells and bury themselves in mud to survive dry spells. This survival strategy allows them to persist through seasonal changes and thrive in both tropical and subtropical climates.

The spread of apple snails in the U.S. is largely due to irresponsible aquarium dumping. When aquarium owners decide they no longer want their snails—often because they’ve grown too large or become too numerous—they sometimes release them into local waterways. This seemingly harmless act has had severe consequences. Reports of apple snails in the U.S. date back to the 1970s, starting in Texas. By 2006, Louisiana had also confirmed their presence.

Bill Walton from the Alabama Cooperative Extension System puts it plainly: “They get too big or too many, and people just dump them. Then they end up in our rivers and ponds.” What started as a backyard hobby can quickly snowball into a serious environmental threat.

The apple snail’s global takeover isn’t a recent phenomenon. In the 1980s, a species of apple snail was brought to Taiwan to start an escargot industry, providing an alternative source of protein for rice farmers. But the plan backfired. The snails failed to catch on as a popular food source among locals, and worse, they carried a dangerous parasite—Angiostrongylus cantonensis, or rat lungworm. If consumed without being properly cooked, this parasite can infect humans and cause severe illness. On top of the health risks, the snails began destroying rice crops and native plants. From Taiwan, they spread across Asia and eventually reached Hawaii, where they further disrupted agriculture and aquatic ecosystems.

In the United States, apple snails are now seen as a serious threat to agriculture, public health, and commerce. Their spread has prompted calls for national quarantine measures. In fact, the European Union took action in 2012 by banning the sale and release of all apple snails in an effort to prevent their expansion.

The eggs of apple snails are particularly troubling. Each clutch can contain between 500 and 700 eggs. Laid in clusters on solid surfaces above the waterline—like rocks, plants, and dock walls—they appear as eye-catching pink or orange pearls. But these beautiful little beads are the beginning of a serious infestation.

If you spot apple snail eggs, take immediate action. First and foremost, avoid touching them with bare hands, as the snails can carry harmful parasites. Always wear gloves when removing them. Use a plastic scraper or spatula to gently remove the eggs, or a soft brush if they’re especially stubborn. Place the eggs in a sealed plastic bag, crush them to ensure they don’t hatch, and dispose of them in the trash—never in a toilet or drain, as this could lead to further spread.

Inspect the surrounding area for adult snails and remove any that you find. While adult snails are easier to detect, the real key to stopping their spread is eliminating the eggs before they hatch. Acting quickly can stop an infestation before it starts.

If you’re already dealing with adult snails, freezing is one of the most effective methods to kill them. For a permanent solution, freeze them at 0°C (32°F) for about 12 hours. If you need to temporarily sedate them for easier handling, a half-hour in the freezer at 5°C (41°F) will do the trick. Just remember to dispose of them responsibly afterward.

In the garden, limiting their habitat can help. Apple snails need fresh water to survive, so draining ponds or standing water can significantly reduce their presence. Without water and food, they’ll be forced to move on—or die off.

In conclusion, while apple snails might look fascinating or even beautiful, they’re anything but harmless. Their rapid reproduction, resilience, and adaptability make them a real threat to local environments. By taking simple steps like removing eggs, freezing adult snails, and reducing water sources in your garden, you can make a huge difference. Stay alert, act fast, and don’t hesitate to educate others. The more people know, the better chance we have at keeping these invasive pests in check.