For now, I live in Miami-Dade County Florida, where sea turtle nesting season (typically) ranges from May 1 to October 31. Why am I writing about it in November? Well this is the first time I've had to catch a break and take a moment to breathe and reflect on the crazy year that's almost over! But beyond the personal stuff - let's talk turtles! Given that I grew up on the West Coast, I knew next to nothing about sea turtle ecology when I started working. In the 6 months I had the pleasure of working with sea turtles I learned a lot, and so I thought I'd take this time to get up on my soapbox to share some of that knowledge. :) Here in Miami, we have 3 main species of turtles that nest: Loggerhead (Caretta caretta), Green (Chelonia mydas), and Leatherback (Dermochelys coriacea). In addition to the 3 main nesting species, we have 2 additional species that like to hang out in Miami waters - the Hawksbill (Eretmochelys imbricata) and Kemp's Ridley (Lepidochelys kempi). Sea turtles have a pretty cool life cycle, starting their lives as tiny little hatchlings that emerge from the sand at night. These hatchlings crawl towards the ocean where they swim OUT and they swim FAR to spend their young years out in the open ocean. Shockingly, only about 1 in 100 hatchlings that makes it to the ocean survive to adulthood. That statistic is CRAZY - how do we have any turtles today? Especially considering that they were hunted to near extinction not so long ago (sea turtles are currently protected under the Endangered Species List in 1973). But I digress. Once they make it to sexual maturity, the sea turtles move inshore during breeding season to mate. After breeding males will return to their offshore existence - they never come back on land after leaving it as a hatchling! - whereas females will come up on shore to lay their nests. Depending on the species, sea turtles can nest a few times a season (2-5 times), laying between 80 and 120 eggs per nest! These eggs will incubate in the sand and, like other reptiles, the sex of the hatchlings is determined by the temperature of the sand around the nest. Warmer sands make female turtles and cooler sands make male turtles - so we say that we get Hot Chicks and Cool Dudes, a phrase which gave me no end of amusement throughout the season. So what do you do as a sea turtle nest monitor here? Well, as I mentioned in my first post on turtles in April, we get up early. An hour before the sunrise we get to work, and begin surveying half an hour before the sunrise so we can see the tracks with the best accuracy (in addition to the perk that there are fewest people on the beach at this time of morning). Loggerhead sea turtle tracks. Each species has a unique pattern to their track making identifying the turtle easy even though we haven't seen the turtle nesting typically. When we locate tracks we have to take data on whether the crawl resulted in a nest or not. If it resulted in no nesting attempt, this is called a "false crawl". Mother sea turtles will false crawl for numerous reasons including people or anthropogenic lights disturbing her, her not liking the sand, or other reasons. However, if the crawl results in nesting, we get to mark off the nest to make sure that no one interferes with the incubating eggs. A loggerhead sea turtle nest. Similar to how each sea turtle species has species-specific tracks, each species that nests in Miami has a specific nest shape! After the eggs incubate and hatch, the county sea turtle nest monitors get to dig into the nest to take data on the nest itself like how many eggs hatched. Sometimes, we'd get stragglers too - hatchlings that didn't quite make it out of the nest with their brothers and sisters. By far this was my favorite part of working with the sea turtles because these were the only living turtles we got to see while working! When we'd get these stragglers, we'd get to let them rest in a safe and dark environment and let them go at night. The first hatchling release I got to do was probably one of the most magical moments I've experienced to date. And to be entirely honest, I felt a little like Moana in the first scene of the movie where she helps the baby turtle safely to the sea. And I think that's about as close to being a Disney princess as I'm ever going to get so I guess there's really not much more I can look forward to in my career (I'm KIDDING). A loggerhead hatchling to complete our loggerhead nesting adventure. A leatherback hatchling because I just think they are the coolest turtles around. Not gonna lie, I love how derpy they look. Leatherbacks spend the vast majority of their lives in the open ocean which is why they have enormous flippers. As babies I think it really just makes them look disproportionate and I LOVE it. **All photos in this section of the post were taken by me in Miami-Dade County under FWC Permit number 19-017. Sea turtles still face a lot of threats! A really large concern that I feel after working in Miami is the problem of artificial lighting. Artificial lighting causes sea turtles (both adult and hatchling) to become disoriented. Artificial lighting leads to the death of thousands hatchlings every year in Florida. Why does this happen? Great question! To begin our story, sea turtles evolved millions of years ago and as a way to get to the water, hatchlings have evolved to emerge from the sand and go towards the brightest horizon. On a secluded beach (or a beach before civilization), the brightest horizon will be the sky and horizon as well as the reflection of the stars on the ocean. This all changes when we throw people and big cities into the equation. If you've ever been outside at night in Miami, you know how BRIGHT the city is - and from the water, you can see the glow of downtown for an alarming distance off the coast. This has deadly implications for our hatchling sea turtles, and can also lead to the disorientation of mother sea turtles as they attempt to nest. All in all, it is a heartbreaking situation with a relatively easy solution. Sea turtles are not disturbed or disoriented by long wavelength light. Specifically, amber lighting is particularly good for sea turtles and allows us humans to be able to see at night without leaving areas unlit. Win win, right? This solution is only kind of effective here in Miami because although we have lighting ordinances, they are poorly enforced, which leads to the disorientation of dozens if not hundreds of hatchlings each year. Another problem associated with turtles is plastic. Plastic affects not only adults sea turtles, which commonly mistake plastic bags for jellyfish, but also recently hatched turtles, which will eat plastic instead of food particles and die. Another viral video features a scientist removing a plastic straw from the nostril of a sea turtle (it's really graphic so please take this as warning). Obviously the plastic issue is one that is near and dear to my heart, but it is manifesting in these peaceful, incredible creatures that have been on Earth a lot longer than we have. Of course, the solution to this problem is one that has far reaching implications, but the use of plastic bags and straws and products can be mitigated by exercising consumer choice and spending money where you want to see it going - such as to organization working to decrease the amount of plastic in the oceans or by reducing your own plastic footprint. (I'm getting off my soapbox now XD) Green sea turtles (mostly) contract a disease called Fibropapillomatosis (FP) which manifests in tumors. These tumors can hinder turtles numerous aspects of their life including swimming, feeding, and seeing. This disease can be transferred turtle to turtle through touch, and is commonly transferred through sexual activity. Though these tumors can lead to death, they can also be removed by sea turtle hospitals with the appropriate facilities. :) Yay for there being hope sometimes. A healthy green sea turtle I spotted snorkeling in Maui! If you encounter a sea turtle in distress in Florida, please call the Florida Fish and Wildlife Conservation Commission Injured Animal Hotline at 1-888-404-3922.
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AuthorBree Gibbs, here. I'm a recent Master's Grad just trying to share what it's like to be a trash scientist (for those who aren't in the know, I'm a marine biologist). Categories
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