Close your eyes and imagine your perfect tropical vacation: dragging a suitcase across the sweltering weather, you might expect a bouquet of multicolored coral. Perhaps even schools of fish playing hide and seek between the vibrant coral palaces. But if you have recently visited beaches stretching from India to Hawaii, Thailand to Florida, you would have undoubtedly seen a strange chalky dullness across the coral reefs. As summer approaches, reports of severe coral bleaching have rampaged throughout the news today. But what is behind this loss of colors?

Image Source: Greentumble, How Does Tourism Affect Coral Reefs?

Image Source: BRIDGE Ocean Science Education, Coral Bleaching: a White Hot Problem
The central cause of coral bleaching is the abnormally high water temperatures. Coral cannot survive in water temperatures exceeding 1° Celsius from their optimal temperature, which is usually between 23° -29° Celcius (“Coral Bleaching”). However, global warming has spiked ocean temperatures to unseen levels. In 2023, NASA described this trend change as a fever —the ocean’s heat has been a sickness that has pounded widespread devastations for coral health (“The Ocean has”). In these extreme temperatures, zooxanthellae, a special type of algae that sustains coral’s energy through photosynthesis, cannot survive. Zooxanthellae are forced to leave the coral, leaving them to die slowly. Without the zooxanthellae’s protectance and nurturement, coral does not produce pigments with their flashing colors (“Why corals are”). The loss of zooxanthellae detracts from the coral’s trademark vibrance, dulling them into a lifeless white.

Image Source: NOAA, What is coral bleaching?
Tourism is another major culprit behind coral bleaching. Chemical release or fuel-related emissions from boats exacerbate the unsustainable heat of the ocean (Cossio). Marine activities can also jeopardize coral. Furthermore, accidentally touching or kicking coral when snorkeling in shallower oceans destroys the delicate coral surfaces. However, receiving guidance from professionals could make snorkeling a safer experience—for both snorkelers and the coral around them. In the crossroads between a worsening environmental crisis and the lively rebound of tourism from its low point in the pandemic, balancing environmental health with human recreational activities is at a pivotal point (“Global Tourism”). While the joy and memories humans can make as they enjoy the beauty of coral reefs are immense, thoughtless tourism evokes coral stress and heightens bleaching rates.
But what could we do to turn this trend around? General approaches include minimizing your carbon footprint or cutting down plastic usage. But within the context of coral watching, conducting coral color surveys is a special way that any tourist can contribute. While we often imagine a strict image of scientists as professionals in white lab coats, individuals from any educational level can participate in this citizen science of coral data collection. By using a small waterproof coral survey chart, such as the standardized one below, you simply check off the darkest and lightest coral colors you see.

Image Source: Mallender, "CoralWatch- so easy you can do your own survey."
In school service trips or within a marine community, snorkelers can use such standardized coral color palettes to record coral bleaching (Mallender). This data indicates the devastation or rebound of coral health in your vacation location. Sharing this data with international websites can widen the data repertory which governments create and refine ways to preserve coral reefs. We need to reverse the worsening changes to prevent the coral’s vibrance from fading away. If we continue destroying the coral with our tourism, these coral reefs will be rendered as mere memories from past vacations, a ghosty shadow of what once existed. So the next time you visit a coral reef, try some simple ways that you can contribute to protecting the coral’s vibrance. With such initiatives, you could transform a simple enjoyment into a meaningful contribution to the coral and the wider marine ecosystem.
Works Cited
"Coral Bleaching A White Hot Problem." BRIDGE Ocean Science Education, masweb.vims.edu/bridge/datatip.cfm?Bridge_Location=archive0406.html. Accessed 11 June 2024.
Cossio, Camila. Coral Reefs and the Unintended Impact of Tourism. Earth Justice, earthjustice.org/article/coral-reefs-and-the-unintended-impact-of-tourism#:~:text=How%20Tourism%20Threatens%20Corals,them%20and%20become%20completely%20white. Accessed 11 June 2024.
"Global Tourism Statistics 2024:Facts and Forecasts." WP Travel, wptravel.io/global-tourism-industry-statistics/#:~:text=Global%20tourism%20saw%20significant%20declines,forecasted%20to%20be%20around%2034.7%25. Accessed 11 June 2024.
"How Does Tourism Affect Coral Reefs?" Greentumble, greentumble.com/how-does-tourism-affect-coral-reefs. Accessed 11 June 2024.
Mallender, Simon. "CoralWatch- so easy you can do your own survey." Diveplanit Travel, 22 Oct. 2016, www.diveplanit.com/marine-environment/coralwatch-easy-survey/. Accessed 11 June 2024.
"The Ocean Has a Fever." NASA Earth Observatory, 21 Aug. 2023, earthobservatory.nasa.gov/images/151743/the-ocean-has-a-fever. It was accessed 11 June 2024.
"What is coral bleaching?" National Oceanic and Atmospheric Administration, oceanservice.noaa.gov/facts/coral_bleach.html. Accessed 18 June 2024.
"Why corals are so colorful?" Woods Hole Oceanographic Institution, www.google.com/url?q=https://www.whoi.edu/know-your-ocean/did-you-know/why-are-corals-so-colorful/&sa=D&source=docs&ust=1718077444021397&usg=AOvVaw0Ll9IIV30zRleINZ0CDI__. Accessed 11 June 2024.