Are Manta Ray Expeditions Harmful to Manta Rays?

by | Mar 3, 2019 | Swimming with Manta Rays, Hawaii Travel

A fairly common question among people who love and want to protect animals is “can manta ray tours harm the mantas?”. What effect can the manta ray expeditions (where tour operators take guests into the ocean to swim with manta rays) have on the manta population?

Text on image of manta ray: "Can night time feeding snorkel expeditions have a negative impact on the manta rays?"
I wrote this article after Vera, a member of our Manta Ray Advocates Facebook community, asked the question in the group.

Considering that we have over 100,000 visitors annually experiencing the mantas of Kona, Hawaii, this question has come up before, and today I want to share two viewpoints with you:

  1. The perspective of the mantas: they come to the viewing sites to feed, but would they starve without them?
  2. The human standpoint: can we strike a balance where the tourism industry doesn’t overpopulated the manta ray viewing sites?

Manta Ray Viewing Sites in Kona, Big Island of Hawaii

Let’s start with a quick recap of what has been happening along the Kona Coast since the early 1990s.

Planktonic marine life (and the mantas’ diet) is attracted to light at night.

Almost every evening of the year underwater lights are set up shortly after sunset to attract the plankton and manta rays are drawn to the lit up areas to filter-feed the plankton from the water.

Through classical conditioning, we encounter the mantas regularly with a sightings success rate of over 70%.

The manta experience started with one location in 1991 and since then expanded to three viewing areas along the coast.

Read more about these viewing areas here!

The 3 Manta Ray Viewing Sites in Kona, Hawaii


Do the Manta Rays Need Night-Time Feeding?

If we were to take away the lights at the regular nightly feeding grounds, would the mantas starve and be negatively affected as they’ve become dependent?

No, they would not starve.

Thanks to efforts to identify and name individual manta rays, in-depth statistics, and many years of observing them and their behavior night after night, it has become clear that we see many different individuals either regularly or irregularly.

“Regular sightings” mean we see a manta ray 150-200 times in a year versus a manta we only see 1-30 times.

In 2013 Koie Ray was seen 218 times at the manta viewing sites. As manta rays swim and eat continuously, this means that she ate somewhere else 147 times. We have seen the same pattern also with other mantas like Jana Ray, Amanda Ray or Big Bertha.

Often times a manta would not show itself at any of the viewing sites for several weeks, months or even years before it suddenly re-appears.

In other words: if the mantas don’t feed of the plankton that gets attracted to the viewing sites, they have no problem finding food elsewhere.

Besides, we’re not attracting manta rays to our moonlight swim activity by bringing them food; instead, the amount of plankton at a viewing site would either be abundant or not.

Manta Ray Expeditions and Marine Ecotourism in Kona, Big Island of Hawaii

In the past decade, enormous efforts have been made to install tour operator standards (for the tourism industry) and guidelines for passive interaction with the manta rays (for the tourists… and their guides).

This means that in a perfect world, every participant would be briefed prior to entering the water to ensure a safe and enjoyable experience for both parties (human and manta). That’s a win-win situation: while the mantas feed, the humans have a chance to experience a truly breathtaking display of Mother Nature.

But the perfect world only exists with a healthy number of people and boats at the sites.

Unfortunately, the Kona manta industry has had exponential growth since 2012 with more boat operators starting their businesses and ultimately have brought a lot more people to the activity sites.

The healthy balance that existed since 1991 has been out of whack and on busy nights you can easily end up with 200-300 people in the water at one site. It is an organizational big stressful challenge as we all must try to keep the situation safe for everyone involved at night in the ocean with “big fish”. Read all about the current state of ocean ecotourism around Kona on this page!

The State of Hawaii is working on regulations but that is a painstakingly slow process and definitely, a topic that will be revisited here on the Manta Ray Advocates website.

Protecting Manta Rays in Hawaii

Are Manta Rays Facing Extinction?

Join the Conversation in the Facebook Community


Click here to join the community where you will find a Facebook Live event live about the same topic. Become a manta advocate and be part of a highly educational and fun place to meet others who want to make the mantas’ world a better place.

With Aloha



Submit a Comment

Your email address will not be published. Required fields are marked *

More things you’ll love!