Are Manta Ray Expeditions Harmful to Manta Rays?

by | Mar 3, 2019 | Swimming with Manta Rays

The last two weeks were very exciting as they were the start of our new Manta Ray Advocates Facebook Community, the place for all those passionate about the gentle giants and ocean conservation.

In case you missed the invite, click here and come on over to join the 100% free online community.  As hoped, it is already not only a gathering of ocean lovers, but also a place where members discuss, debate, connect, and brainstorm manta-related topics or take a look behind the scenes.

As an example, I was thrilled to hear from community member Vera wondering whether expeditions are harmful to manta rays:

Can night time feeding snorkel expeditions have a negative impact on the manta rays?

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. Mantas Perspective
  2. Human Standpoint

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

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.


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 easy identification and naming the mantas, in-depth statistics, and many years of being with them, 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 sites which also shows that she fed 147 times somewhere else. Often times a manta has taken a break from the activity sites for several weeks, months or years before it re-appeared.

We have seen the same pattern also with other mantas like Jana Ray, Amanda Ray or Big Bertha.


I have always enjoyed that the manta experience is not based on a concept that humans provide the food for the activity but is rather based on the plankton amounts that are either abundant or not at the sites.

Plus, thanks to established Manta Ray expedition guidelines every participant should be briefed prior to entering the water to stay in passive interaction with the creatures.

In a perfect world it is a win-win situation. The mantas feed and the humans have a chance to experience a truly breathtaking display of Mother Nature.

Aiden’s Motto: “Nothing I Can’t Do!”

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. Today there are over 50 manta activity providers (up from approx 25 in 2012).

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”.

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.

So thank you Vera for asking this great question and giving me a chance to shine more light onto the sustainability aspect of human interactions with manta rays!


We hope this quick Q&A inspired you to join the conversations online too!

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



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