One of the most popular charismatic mega fauna in our waters is the spotted eagle ray. No matter where I have ever been, Caribbean or Pacific, time stops when I see an eagle ray. I have not been stopping much lately. And I have been wondering why.
In May of 2011 we saw bunches and bunches of eagle rays. On one dive my buddy Phil stopped counting at 50. I have a few proof-of-life images with about 15 in the frame. I have come to find out that was a fairly unusual experience. I did not know that at the time, and thought we would be seeing them in bunches again the next spring. It never happened.
There is a good lesson here. An observer may not have a full appreciation for what was witnessed until well after the event. For example, the giant barrel sponge spawning event we saw last April was a rare experience. These go in the incredible opportunity category.
I never thought the eagle ray incident was all that significant until I looked at some recent research from Mote Marine Laboratory. And now, as I am contemplating all the information before me as part of the Ecosystem Protection Working Group, I realize there are many things that require more scrutiny. An ever-increasing bank of scientific data will be under consideration as we make recommendations to the sanctuary later this year. Mind boggling, but in a good way.
Just last week another buddy, Walter, posted on ScubaBoard he saw 15 to 20 eagle rays in the flats near Tavernier Creek. Thats about as many in one sighting as Ive heard in a while. Since that event in May of 2011, we have not seen more than seven or eight at a time. Most observations have been single animals, or sometimes up to three at a time. And with a lot less frequency. Why?
Enter Kim Bassos-Hull, the Eagle Ray Lady from Mote Marine Laboratory in Sarasota. She has been studying spotted eagle rays (SERs) since 2009. Her work has centered primarily along the coast from St. Petersburg to Sanibel Island. She is collecting data in the Florida Keys to enhance and expand her studies, but as of today, no critical habitats for feeding, mating and pupping have been identified.
I had the opportunity to have lunch with Kim, Krystan Wilkinson, also of Mote, and Suzy Roebling the other day. Kim and Krystan were passing through Key Largo visiting dive shops that are participating in the SER documentation program. I needed Suzy there to help interpret science-ese to everyday-folks language so I could understand.
According to Kim, there really is more unknown than known about SERs. When I saw the aggregation in May of 2011, I thought that might be an annual event, like the seafood festival, or coral spawning. What she has found is quite interesting.
She gave us a quick run through her presentation, and provided me with a research summary of the Mote project. The number of animals and frequency of sightings has fallen over the last few years. Specifically, since the cold spell in the winter 2009-10, the numbers have been significantly lower.
During that cold spell, 16 rays washed ashore in the warm water area surrounding the Big Bend power plant near Sarasota. They were all emaciated, and necropsies on a few of them revealed they had very little or no food in the digestive tract. They starved.
Kim and the Mote crew have captured, documented and tagged over 300 rays in the last four years. They also have an extensive aerial survey to spot rays inside the research area. Individual SERs can be identified by the unique spot formations and shapes. Each ray is unique. They photograph the head of each captured ray, and submit the photo to a software application that maps the spots. This software was originally developed for mapping stars, then modified to map the spots on whale sharks, and now, rays. Over time, if an individual is captured again, they can identify it and update the vital statistics.
Bet you didnt know that SERs have donuts and peanuts, did you? Thats the official spot-type designator. Gives me a whole new definition for peanut gallery.
One area of concern is the migratory patterns and the extent of the range. A DNA database is being constructed that will shed light on diversity between the Gulf of Mexico, the Keys, Mexico and Cuba. We wont know if the rays travel throughout the entire range and if the populations share the same gene pool until the DNA evidence is examined between the countries.
Kim leaves this week for Mexico to work with marine biologists there to begin adding to the data. They eat SERs in Mexico. Right now, all their data come from their catch statistics. The most recent annual figure puts 7,350 eagle rays on dinner plates.
If we are getting rays migrating from Mexico, and the activity is not sustainable, what will the impact be on the SER population in the Keys?
Lots of questions, not enough answers... yet. Mote needs your help. They have an online form to report eagle ray observations. Watch this short video from the California Academy of Sciences, a Mote partner, here: http://www.calacademy.org/sciencetoday/spotted-eagle-rays/ Then, next time you see a SER, please use this form to report the observation: http://www.mote.org/eagleray
As Suzy says, Eagle rays are majestic.....they take my breath away when they fly by. Lets hope we learn how to keep the airport open, and sustain the runway.
Tim Grollimund is a freelance photographer and PADI divemaster based in Key Largo. He can be reached at firstname.lastname@example.org or through his web site at www.timgimages.com. Tim is a member of the Ecosystem Protection Working Group for the Florida Keys National Marine Sanctuary.