NOTABLE NATURAL EVENTS
While everything you’ll see at Flower Garden Banks National Marine Sanctuary is pretty amazing, there are some events that truly stand out.
Coral Spawning
Every year, about 7-10 days after the full moon in August, usually between 9 p.m. and midnight, several coral species at the Flower Garden Banks sanctuary participate in a mass spawning event. At this time, coral heads release their gametes into the water column where they can mix and fertilize, later becoming larvae that settle to the bottom and start new coral colonies. It’s like an underwater snowstorm, in reverse!
While sanctuary researchers have become quite good at predicting which coral species will spawn at what time, we still have a lot to learn. If you see corals, or any other animals, spawning in the sanctuary, please make note of the place and time and report your observations to the sanctuary office. Photographs of the spawning are also appreciated.
See videos of corals and other animals spawning in the sanctuary.
Eagle Rays
Spotted eagle rays are known to school in and around the Flower Garden Banks sanctuary during the early part of the year.
See video of spotted eagle rays and other rays in the sanctuary.
Hammerhead Sharks
In the early part of the year (January through March) it's not unusual to see large schools of scalloped hammerhead sharks. Scientists don’t truly know the reason for this seasonal schooling, but have noted that it’s a regular occurrence in this part of the Gulf of Mexico. They’ve also noted that all of the sharks appear to be male.
See video of hammerheads and other sharks in the sanctuary.
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Manta Rays
While there is no special time to expect manta rays at the Flower Garden Banks sanctuary, it is still an awesome experience to see one or more. These large rays glide over the reef, often swooping and turning, to capture plankton in their large open mouths. Distinctive flaps on either side of the mouth let you know that they are in fact mantas, and not stingrays.
Research has already shown that there is a resident population of mantas, but scientists are now attaching acoustic tags to various mantas learn more about their ranges and activities.
Each manta can be identified by the unique markings on its underside. Photographs and video of these markings are most helpful for making positive identifications. Please report your observations of manta rays to the sanctuary office, especially if you have photos to share.
See videos of mantas and other rays in the sanctuary.
Sea Hares
We'll be the first to admit that most people have never even heard of sea hares, let alone knew they did anything special. But, we can't deny that they are unusual looking and what they do in groups is, well, a bit peculiar.
In June 2006, sanctuary researchers noted large numbers of sea hares at Stetson Bank. Sometimes these large, shell-less snails would swim around, using their mantle skin flaps like wings. At other times, groups of sea hares would lie on the bottom and form unique "chains" of animals, which is apparently a mating behavior.
This is the only time such an event has been seen in the sanctuary, but that doesn't mean it won't happen again. If you happen to see this type of activity, please report your observations to the sanctuary office.
See a video of sea hares in action.
Squid Aggregations
In August and September, if you look closely, you might see small squid in large groups hidden among the coral spawn, just above the reef and up in the water column. These are the elusive Roper’s inshore squid (Loligo roperi) which form mating aggregations over the Flower Garden Banks.
Though it is unclear why these squid aggregate over the banks during coral spawning, there are several possibilities. Squid might be feeding on coral spawn, which has a high fat content and is a burst of nutrition for a lot of reef dwelling animals, or they could be using the spawn as ‘cover’ to hide from predators while conducting their own spawning, or mating, behavior.
Both juveniles and adults make up these aggregations, which means not all the squid are mating. This only adds to the mystery behind the purpose of these aggregations.
Since we are still learning about these squid and their behaviors, if you happen to see any, please report your observations to the sanctuary office.
Click here to see video of octopus and squid in the sanctuary.
Whale Sharks
We wouldn’t go so far as to say that whale shark sightings are ever “common” at the sanctuary, but they are definitely not out of the question, especially during July, August and September. Whale sharks seem to prefer the calmer surface conditions typical of that time of year as they cruise along gulping great quantities of plankton. Scientists are hoping to attach acoustic tags to whale sharks in the sanctuary in an effort to learn more about their ranges and activities.
In the meantime, a whale shark that was tagged off the Yucatan Peninsula in Mexico has visited Bright Bank in the northwestern Gulf of Mexico (about 14 miles from East Flower Garden Bank!). This confirms some level of biological connectivity between the northern and southern parts of the Gulf.
As we continue to learn about these animals, we appreciate information on any whale shark sightings. Please report your observations to the sanctuary office.
Click here to see video of whale sharks and other sharks in the sanctuary.
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