Showing posts with label Loggerhead. Show all posts
Showing posts with label Loggerhead. Show all posts

Friday, November 29, 2013

The Sargasso Sea and the North American Eel: An Interview With Dr. Joe Richardson

In our last post, we looked at the difference between anadromous and catadromous fish, as well as several examples of each type of fish.  Eager to learn more, I contacted several people who have been very helpful to me in the past so that I could learn more.  One of these people was Dr. Joe Richardson, a marine biologist who gives Ecology Tours (which I highly recommend) on Tybee Island in Georgia, and whose Facebook page can be reached by clicking HERE.  Dr. Joe has helped me out a lot in the past, including providing a guest post about moon snails way back in February (which can be reached by clicking HERE!  When my family and I were on the Ecology Tour several years ago, I remember Dr. Joe mentioning something about the Sargassum seaweed that could be found on the beach.  Therefore, when I was researching the North American eel for the anadromous/catadromous post and I came across mentions of this same seaweed, I decided to ask Dr. Joe a few questions about the eel and the seaweed.  I wanted to make sure that you all could benefit from his knowledge as well, so I am reproducing the interview here!  
A picture of Dr. Joe holding a Portuguese Man of War!  WARNING: TRAINED PROFESSIONAL.  DO NOT ATTEMPT TO PICK UP A PORTUGUESE MAN OF WAR IF YOU HAVE NOT RECEIVED PROPER TRAINING.  Photo Credit: mermaidcottages.com
The Natural World:  First off, what is it you're holding in the picture above?

Dr. Joe:  It's a Portuguese Man of War.  They sting real bad.  They are more of an open water, tropical species, but they float (I'm holding it by the float) so they go wherever the wind blows them. We don't get many on Tybee Island, but on some Florida beaches they can be a real problem.

TNW: Didn't you guys find another one pretty recently on one of your Ecology Tours?

Dr. Joe: Yes, within this past week. We found two of them washed ashore during one of my Tybee Beach Ecology Trips. I sure didn't expect to see them; but most anything is likely to wash ashore.
A picture of this weeks Portuguese Man of War.
TNW:  In a recent post, I discussed the North American eel. I was wondering whether you have any pictures or stories regarding the eel that you'd like to share!

Dr. Joe:  I don't have any pictures of the American eel; but my experience with them is that I always hated to catch one when fishing because they were so slimey.  And they would invariably wrap themselves around the rig and line so they were a mess to get unhooked.  The slime was also thick and would stay on the line even after you got them off.  Many years ago, while in college, I worked one summer in North Carolina on a shrimp boat and was involved in a few research projects on the side.  One involved developing eel traps to be used for catching eels in the inshore waters.  They were trying to create a business opportunity for catching eels, then somehow shocking them so they would die straight before flash freezing them.  By being straight, they could pack more of them in boxes than if they were all curvy.
The North American eel.  Photo Credit: cbf.typepad.com
TNW: I also found that the eel spawns in the Sargasso Sea, and I recall you talking about all of the Sargassum seaweed washing up on shore when we went with you on the tour several years ago.  What can you tell me about this type of seaweed?

Dr. Joe:  This species of Sargassum (a brown seaweed) is unlike most seaweeds, that have to grow attached to a hard bottom or structure in shallow water where they get enough light to do photosynthesis. This Sargassum actually grows unattached, floating in open water, generally well out in the Atlantic Ocean. In fact some charts refer to the middle of the Atlantic Ocean as the “Sargasso Sea” because there is lots of it floating around out there. The small berry-looking structures on the Sargassum are actually air floats that keep it floating near the surface. Clumps of Sargassum in the open ocean serve as places to hide for some animals and as structure for some small animals to attach on to. During late June, we found lots of those small animals (Sargassum shrimp, Sargassum Swimming crabs, small file fish, baby flying fish) on the beach and in tide pools because they have washed in with the seaweed clumps. All these animals are yellow-orange in order to camouflage or blend in with the seaweed. So the Sargassum has brought with it lots of interesting animals from far offshore, that we normally don’t see on our beach.
Pile of Sargassum seaweed along the high tide line at North Beach.
The berry-like structures on the Sargassum are actually air floats that keep the seaweed at the sun-lit surface.   
Sargassum shrimp (this one carrying eggs under her abdomen) were abundant in some of the clumps of seaweed.
This was one of many Sargassum swimming crabs that were common for a few days on Tybee's ocean beach. 
Small filefish with camouflage colors matching the seaweed were found among many of the Sargassum clumps. 
Although only about an inch long, what appears to be a baby flying fish was another type of fish found among the drifting seaweed.
TNW: Besides the eels and the other small animals you mentioned above, what other animals live in the Sargassum?

Dr. Joe: The floating clumps of Sargassum in the open ocean also serve as places to hide for small young animals that will eventually become larger as they age and grow. When the baby Loggerhead Sea Turtles hatch on Tybee’s beach later this summer, they will head out to sea, and many will hide among clumps of floating Sargassum far offshore. Many years ago, while on a research cruise offshore, we anchored overnight and found ourselves among a large area of floating Sargassum. Being curious scientists, we used some long dip nets to catch some clumps of the floating seaweed to see what sort of animals were among it. This was how I caught the only Sailfish I’ve ever caught!
Baby sailfish hide among the floating clumps of Sargassum far offshore.
TNW:  Do you know why Tybee was inundated with Sargassum when we visited in the summer of 2012?

Dr. Joe: I don’t recall our having a prolonged period of strong winds from the east, so I don’t think it was necessarily a wind-blown event. Instead, I’ve got a different hypothesis. The Gulf Stream current flows from the south toward the north well offshore of Georgia’s coast. It doesn’t flow in a straight line, but meanders a lot. Sometimes those meanders can be almost like huge hair-pin curves, and sometimes those big meanders, like loops, can break off and form large circular or oval water masses of warm off-shore water. If such a large ring of Gulf Stream and warm Atlantic Ocean water (and possibly water that recently had been in the tropics) happened to break off on our side of the Gulf Stream, it could gradually move toward our coast, and bring with it things like Sargassum. This is my guess: one of these offshore water masses, with its floating Sargassum, broke off and had moved into our coastal waters.
Laying among a pile of Sargassum seaweed along the high tide line was this lumber that had been drifting offshore long enough for these Goose-neck Barnacles to settle and grow. This species of barnacle only grows on drifting, open-water objects.
TNW:  What other ecological or biological effects did this inundation of Sargassum have on the coastline?

Dr. Joe:  Since the Sargassum seaweed event on Tybee, I’d been noticing (almost daily while conducting my Tybee Beach Ecology Trips) additional tropical and offshore species of animals. There was a group of Sargent Majors, a small black and white striped damsel fish that is common around coral reefs and rocky shorelines in the Caribbean and Florida Keys. They don’t belong this far north. We also got a Ballyhoo, a strange looking fish with a long extended lower jaw; and they usually live offshore where they are food for large gamefish like sailfish, marlins and dolphins.  So I’ve got a feeling that the Sargassum and all these other interesting tropical and offshore animals are signs that Tybee had been the landfall of a large warm water, open-ocean water mass. It sure made beach ecology on Tybee interesting this spring and summer!!
Small Sargent Major damselfish, common on coral reefs and tropical rocky shorelines, have shown up on Tybee in the last week. 
We've been seeing Ballyhoo in the beachwater, but they normally live in warm offshore open waters.
I would like to take this opportunity to thank Dr. Joe for taking the time out of his schedule to chat with me for a bit about these fascinating animals, and the importance of the Sargassum!  I look forward to hearing more from you in the future, but in the meantime, make sure you like the Facebook page for his Tybee Beach Ecology Tours by clicking HERE, and make sure you check out his website HERE.

Unless otherwise noted, the photo credit for all of the pictures in this post goes to Dr. Joe Richardson.

Monday, July 1, 2013

Sea Turtles on Tybee Island and the Tybee Sea Turtle Project by Amy Capello, Guest Blogger

Last summer, my family and I took an ecology tour with Dr. Joe Richardson on Tybee Island off the coast of Georgia and South Carolina.  These tours, called the Tybee Beach Ecology Trips, were a fantastic way to learn more about the local sea life of Tybee.  When we returned home, I became a fan of his tours on Facebook (you can too if you click HERE), where he shares lots of cool photos from the days catch.  Since then, Dr. Joe was generous enough to do a guest post here on the blog, which you can read by clicking HERE.  Over the last year, he has also shared numerous photos from another Facebook page for the Tybee Sea Turtle Project (which you can visit by clicking HERE).  I decided to contact the folks at the Tybee Sea Turtle Project as well to ask if they would be interested in doing a guest post, and I got back some fantastic material from Amy Capello, a volunteer involved in the Sea Turtle Project!  So without further ado, I'm going to let Ms. Capello tell you all about the project, and how to help out the sea turtles!  
Loggerhead sea turtles, Caretta caretta, are a common species of sea turtle found on Tybee Island and all along the Georgia coast. There are several species of sea turtle found throughout the world, all of which are threatened or endangered. Due to their status, there are many efforts being made to protect these amazing creatures. The Georgia Department of Natural Resources is responsible for monitoring sea turtle populations throughout the state. This is a large project to undertake and depends on sea turtle volunteers on every island in Georgia. On Tybee Island, the Sea Turtle Project is headed by a wonderful, dedicated local named Tammy Smith. She is responsible for coordinating approximately 80 volunteers. These volunteers are willing to give up large portions of their time to ensure the welfare of sea turtles. Starting in May, volunteers take turns walking the beach at sunrise to look for evidence that a nesting female came out overnight to lay a nest. Usually, the best indication of a female coming out to nest is her tracks. You might think it’s easy to spot the tracks from a 300+lb. female turtle, but that’s not always the case! Sometimes it can be quite difficult to spot her tracks and the volunteers have to make sure they don’t get distracted by Tybee’s beautiful sunrises and instead focus on potential tracks in the sand.
This is a female that was laying a nest on Tybee. It is a rare occurrence that we get to see the nesting females on Tybee. Some tourists spotted her and called it in and the volunteers were able to go out and see her. She had identification tags and we're waiting to see what other nests she may have laid this season.
Once a nest is located, Tammy will come out to the location and determine if the female laid a nest or simply came out of the ocean and decided to return. Sometimes females will emerge from the water and then change their mind about laying a nest. This could be caused due to disturbances from people who get too close or scare her with their white-light flashlights. It could also be caused due to natural reasons, such as no dry sand to lay a nest during a very high tide. If you encounter a sea turtle while you’re out on the beach at night, keep your distance and make sure that your presence doesn’t change the natural behavior of the turtle. Any living sea turtle you may see on the beach is a female; males will never come out of the water, so make sure to give them their space to do what they came to do! Remember, they are endangered and need to lay every nest they can if we are going to see increases in their population.
This is a false crawl. This means that the female came out of the water to lay a nest and decided not to for some reason.
If a nest is found during a dawn patrol walk, Tammy will determine if the nest is in a suitable location. Sometimes females will lay their nests in a place that may get washed over by high tides and cause the hatchlings to drown. If this possibility is anticipated, we will move the nests to a better, safer location.
A bucket of eggs waiting to be moved. Sometimes the nests are relocated if they need to be moved to a safer place for incubation.
All nests, whether or not they are relocated, are marked with posts and monitored by the volunteers every day on their dawn patrol walks. We make sure that there are no disturbances to the nests, by people or natural predators like ghost crabs.
We mark all of the nests on Tybee Island with a special sea turtle caution tape. The nest is federally protected since the turtles are endangered and only trained and permitted volunteers are allowed to interact with the hatchlings if they require assistance.
The nests will incubate for approximately 50 days, give or take, and then the babies will hatch out. Our volunteers work hard to look for field signs that a nest is going to hatch. When the time comes, we try to be on hand to make sure that the hatchlings make their way to the water safely. I often wish that the nests came with little timers so we would know right when they are going to hatch, but unfortunately, they’re like human babies – they come when they’re good and ready!

A traditional hatching is often referred to as a “boil.” This is because all of the babies hatch out at the same time, appearing to boil out of the sand. It’s a unique experience to get to witness, but since it only takes minutes for the babies to come out, it’s often missed – even by our volunteers! Once the babies come out, they orient themselves with the brightest point on the horizon. A lot of people think they only hatch during a full moon, and this is completely false. However, any light reflecting off the water is going to be brighter than light reflecting off the sand, so the light leads the babies in the right direction. But think about developed islands, like Tybee. There is so much light pollution from inside and outside condos, restaurants, hotels, residences, etc. that often times our babies will head towards those lights, since they are much brighter than the light reflecting off the water. Unfortunately, this means they head in the exact opposite direction of where they are supposed to go. This is why it’s so critical for people to be aware of how much light pollution is out on our beaches. If you are on any island during sea turtle nesting season (May – October), it’s extremely important to turn OFF your lights!! The only “sea turtle friendly” lights are ones that are red-filtered. Even the red-filtered lights, if they are too bright, can disorient a sea turtle, but they are less distracting than a bright white light. If you want to walk the beach at night, consider going without a flashlight or light from your cell phone and your eyes will adjust to the dark. But, if you must have a light, you can purchase red-filtered flashlights in lots of stores like Wal-Mart and Bass Pro Shop. I can’t stress enough how important this is for our babies!
Hatchlings making their way to the sea. These turtles came out earlier in the daytime, allowing for a photo opportunity! All of the babies made it safely to the sea.
Once the little hatchlings hit the water, they are faced with a 24 hour long journey out into the Sargasso Sea where they will spend the first 10-15 years of their lives. They don’t start reproducing until they are about 35 years old. Considering that only 1 in 4,000 survive to adulthood, if we lose any sea turtles before that age, they haven’t even had a chance to replace themselves in the population! In the ocean, they face threats of boats (whose propellers hit them, often fatally), fishing line, and plastic. Plastic in particular looks very similar to one of their favorite foods – jellyfish! Sea turtles have never been to the store and don’t know how to tell the difference between a floating plastic bag and a floating jellyfish.

We love our sea turtles so much and we’ll do anything we can to protect them. We’re so happy that our efforts and the efforts of the public are starting to make a difference! Last year, we broke the record for the number of sea turtle nests on Tybee and overall in the state of Georgia. It was a big year for all of us! We hope to see an increase every year until their populations have fully recovered.

What are some ways you can help sea turtles? Here are some great starting points:


1.  Turn off all lights at night during nesting season (May – October) – this includes buildings, flashlights, and cell phones
2.  Use red-filtered lights if you must use a light
3.  Pick up trash on the beach, especially plastic of all kinds
4.  Do not disturb sea turtles you encounter on the beach
5.  Fill in any holes you dig on the beach and knock down sand castles – these are major obstacles, even to a large turtle
6.  If you are on a boat, keep an eye out for sea turtles and make sure you don’t hit them
7.  Educate others and spread the word! Often times people are willing to do the right thing, they just haven’t been told what the right thing is yet

This was fantastic: thank you very much Ms. Capello, as well as the Tybee Sea Turtle Project, for taking the time out of your busy schedules to teach us about these sea turtles, and what we can do to help!  To support the cause, make sure you check out the project's Facebook page by clicking HERE!  You can also check out the website for the Tybee Island Marine Science Center HERE!  Thanks again, and hope to hear from you guys again in the future!  - Zack Neher

Photo Credit for all of the pictures in the post goes to the Tybee Sea Turtle Project.  
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