From rescues to research: Sea turtle & marine mammal updates - 2020 Annual Report

This story is a highlight from Mote's 2020 Annual Report.


NO SHUTDOWN FOR MARINE LIFE

In 2020, COVID-19 interrupted life as we know it. However, life went on for animals in the ocean—and so did the mission of Mote Marine Laboratory scientists dedicated to studying, monitoring, and helping marine animals survive accelerating environmental threats, which grew no less challenging as the pandemic raged on land.

  • Responding to distressed marine life no matter what

    Mote’s Stranding Investigations Program—which responds 24/7 to reports of distressed or deceased marine animals—answered more than 546 calls to its stranding hotline this fiscal year (Oct. 1, 2019 to Sept. 30, 2020), including 58 calls about dolphins or whales, 248 about manatees, 166 about sea turtles and 74 others.

    This year, Mote’s stranding hotline—covering Sarasota and Manatee counties—changed to a new phone number with an enhanced answering service: 888-345-2335. Outside of Sarasota or Manatee counties, the public should continue reporting strandings to the Florida Fish and Wildlife Conservation Commission (FWC) at 888-404-3922.

    In March through June 2020, Mote received an influx of calls about boat-struck wildlife well before the typical “summer boating season” of June to September, when these strikes are historically most common. Mote scientists also observed increased boat traffic in Sarasota-Manatee waters during March through June, while many businesses were closed due to COVID-19. These and other events prompted Mote’s animal rescuers, scientists and rehabilitators to publish an op-ed piece in the Sarasota Herald-Tribune educating the community about the critical need to respect and protect marine animals

    Many of this year’s calls required Mote biologists to respond on the water or beach. Altogether, Mote biologists rescued or recovered:
     
    • 79 sea turtles (43 found alive, 36 deceased)
       
      • More than half of the 79 turtles showed evidence of human interaction, including boat strike injuries and/or marine debris ingestion or entanglement. It is important to avoid leaving fishing gear and other marine debris in the environment and to follow FWC- and Coast Guard-approved safe boating guidelines to avoid striking marine animals.
         
    • 15 bottlenose dolphins and one spotted dolphin (All deceased)
       
      • Six of these animals had evidence of human interaction, including fishing gear entanglements and a boat strike. One bottlenose dolphin and the spotted dolphin stranded alive but were pushed back to sea repeatedly by members of the public; they died on their own and were recovered by Mote. The public should never push back a stranded marine animal, but instead, should call trained responders immediately.
         
    • Seven manatees (two alive, five deceased)
       
      • Mote assisted in response efforts led by FWC, the statewide authority for manatee rescues. One of these efforts had a doubly happy ending. Over Mother’s Day weekend in May 2020, Mote and local law enforcement officials responded to a distressed manatee with boat-strike wounds near Siesta Key, and the team ultimately partnered with FWC to rescue the animal so it could be transported to SeaWorld Orlando for rehabilitation. There, a veterinary exam revealed the manatee was pregnant, and on May 11 she gave birth to a healthy male calf. On June 18, staff from FWC, Sarasota Police Department and Mote met SeaWorld’s vehicle at a boat ramp near Mote’s Sarasota campus, and together the partners released the mom and calf—nicknamed “Siesta” and “Key”—as well-wishers, some with their own kids in tow, gathered to celebrate this special moment.
         
  • From critical care to happy endings

    This year, Mote admitted 19 patients to its Sea Turtle Rehabilitation Hospital, which provides ‘round the clock critical care with the goal of returning these threatened and endangered turtles to the ocean.

    Despite the challenges of COVID-19, Mote’s hospital team remained dedicated to providing constant care, and as a result, Mote and the community were able to celebrate many successful turtle releases, including:
     
    • “JT,” a massive male loggerhead turtle who was rescued from entanglement in a crab trap and released this year with a satellite-transmitter tag. By tracking JT and other male loggerhead turtles, Mote scientists have seen that these animals can spend a lot of time near shore—unfortunately, this puts them at risk of fishing gear entanglement, boat strikes, impacts from reduced water quality and more. Read more about turtle tracking in our sea turtle research section below!
       
    • “Joyce” and “Hookee” were each rescued because members of the public called Mote’s 24/7 stranding hotline—which was exactly the right thing to do and was critical for saving these animals from life threatening conditions. Hookee, a juvenile green sea turtle, was accidentally hooked by a fisherman, who contacted Mote’s rescue team. Hookee recovered quickly after undergoing surgery to remove the hook from its esophagus. Joyce, an adult female loggerhead turtle found swimming erratically and floating, was reported to Mote and rescued by a team including Venice Police Department, Mote and the Sarasota County Sheriff’s Office. She was named after Venice Police Officer Paul Joyce, the first responder on scene. After months of care, Joyce was less buoyant and able to feed on her own.
       
    • “Finley Joe,” an adult male loggerhead turtle, was brought to the Clinic for Rehabilitation of Wildlife and then transferred to Mote’s hospital for recovery from a boat-strike injury. He’s one of the few lucky survivors of boat strike wounds, which are fairly common in southwest Florida but often deadly. After the long process of helping his shell to heal—using wires to hold it in place—Finley Joe returned home to the Gulf from Casey Key.
       
    • Lots of cute hatchling sea turtles! As September 2020 drew to a close, Mote staff reported that 1,400 hatchling (baby) sea turtles had completed their stay in Mote’s Hatchling Hospital and returned to the ocean. Hatchlings normally emerge from nests on the beach and crawl to the ocean. Sometimes, however, nests are damaged by predatory animals or the hatchlings fail to reach the ocean for other reasons. Notably, hatchlings can become disoriented due to artificial lights on shore. Hatchlings emerge at night and use dim, natural light to find the sea. That’s why residents and businesses near the shoreline should keep the beaches dark, and people should stay off the beaches at night and follow other turtle-friendly tips throughout nesting season, May 1-Oct. 31 in southwest Florida.
       
    • And many other patients that couldn’t have survived without Mote’s care.
       

SEA TURTLE SCIENCE: ESSENTIAL AND EXPANDING

  • Beaches are closed—except to sea turtles!

    When the state of Florida began its temporary shutdown due to COVID-19 on April 3, 2020, Mote scientists and volunteers were about to begin their 39th year of monitoring sea turtle nesting on Longboat Key through Venice, Florida. For Mote, avoiding the closed beaches would mean leaving a gap in the important data they gather each year to support sea turtle conservation.

    Mote scientists spent two weeks working with four municipalities to determine if their Sea Turtle Patrol efforts were essential to city and county operations. The answer was yes—Mote’s Sea Turtle Patrol was deemed essential, not in the way that healthcare providers are, but essential to the community and environment. On April 15, Mote’s Sea Turtle Patrol began monitoring the beaches as usual to document nesting activity (turtles crawling ashore, potentially digging a nest and depositing their eggs, and then returning to the ocean), with city and county permission to access closed beaches. Turtle Patrol volunteers were excited to continue helping these endangered and threatened animals; they trained for the season digitally instead of gathering in person, and they observed social distancing guidelines while walking the beach to help Mote find each new sign of turtle activity—sources of vital data for conservation.

    On Oct. 31, 2020, a month after the current fiscal year concluded, sea turtle nesting season ended on a high note. On Longboat Key through Venice, Mote documented its fourth highest annual nest count in the past 39 years.

    This year's total was 3,716 local nests—including 3,636 laid by loggerhead sea turtles and 80 laid by green sea turtles, both of which are threatened species. Greens laid their second-highest number of local nests in 39 years.

     
  • Tagged turtles reveal their life stories

    In summer 2020 on Casey Key, Florida, Mote scientists encountered nesting sea turtles 570 times and ID-tagged 348 individuals so they can be recognized when they return to nest again—usually every two to three years.

    Mote scientists also deployed satellite tags on three nesting green sea turtles to track their migrations from the nesting beach to feeding grounds at sea, thanks to a grant from the Sea Turtle Grants Program. These threatened turtles seem to be increasing in abundance on Florida beaches, and tracking their ocean journeys is vital for identifying their key habitats and maintaining their recovery.

    As part of an FWC study, Mote scientists satellite-tagged three loggerhead sea turtles and that were originally tagged 9-10 years ago and discovered that they still return to the same feeding areas! One of them is a female nicknamed “Salty” who feeds near Mexico’s Yucatan Peninsula. Salty has been recognized by Mote since 1988, was seen nesting on Casey Key for the 13th time this year, and estimated to be about 60 years old!

    Meanwhile, Mote-tagged male loggerhead turtles “Erick” and “Barron” continued transmitting their locations after two years at sea, and male loggerhead “Mr. T” continued transmitting after one-and-a-half years. This year, “JT” joined the bunch as Mote’s 14th satellite-tagged male loggerhead. Male sea turtles are notoriously difficult to study because they spend their entire lives at sea, usually only coming ashore when rescued due to illness or injury. Mote researchers take advantage of the opportunity to study rescued and rehabilitated male turtles by applying satellite tags onto their upper shells before release.
     
  • Where have these turtles been hanging out? Southwest Florida!

    Erick and Barron, who originally stranded in the Naples/Fort Myers area due to red tide, have largely remained there and have been doing well since their release in 2018. Even Mr. T, tagged in the Florida Keys, found his way to southwest Florida recently. It’s important to identify male turtles’ migration pathways and frequently used areas, especially as Earth’s climate changes. Sea turtles have temperature-dependent sex determination—cooler nest temperatures produce more males, and our warming climate might ultimately reduce the number of male sea turtles. Protecting key habitats for males could become increasing important.
     
  • To paternity and beyond: New turtle research topics

    This year, Mote welcomed new Postdoctoral Research Fellow Dr. Jake Lasala, who helped the Lab to launch or join several exciting sea turtle studies.
     
    • How many males are there?

      Mote scientists are working to estimate how many male and female sea turtles actively contribute to the next generation in southwest Florida—known as the “breeding sex ratio.” While Mote has identified and tagged many mother turtles on the beach, the fathers are hard to count because they mate with the mothers at sea and don’t crawl ashore. This year, Mote scientists began using genetics to help estimate the numbers of breeding males and females—collecting genetic material from nesting mothers and from hatchlings (babies)—which help reveal how many dads fertilized the eggs in a given nest. This project is supported in part by funds for equipment awarded by the Sea Turtle Grants Program.

      Mote scientists genetically sampled nearly 1,500 hatchlings from 112 nests for the breeding sex ratio project. The scientists are also examining hatchlings’ scutes (flat scales) on their upper shells for developmental differences seemingly related to increasing environmental temperatures.

      Mote and Florida Atlantic University (FAU) scientists are also launching efforts to monitor the temperature inside nests—which determines whether hatchlings are male or female—and they plan to place temperature probes into numerous Casey Key nests in the coming year.

      By estimating the numbers of current dads and the number of potential future dads (male hatchlings), the researchers aim to assess whether climate change will skew the breeding sex ratio in ways that could disrupt populations of this threatened species over time.
       
    • Novel study on our nesting beaches

      Mote and FAU scientists are comparing sea turtle nesting success on beaches with and without a beach-armoring structure called a “geotube” (or “geotextile container”)—the first study to do so along the Gulf of Mexico. The researchers want to know if a southwest Florida beach with a Geotube—a sturdy textile tube containing heavy filler material, which is currently installed but slated to be replaced with a seawall on Casey Key—provides better or worse nesting grounds than the planned seawall or a non-armored beach.
       
    • Turtles are what they eat

      Mote scientists are working with FWC to collect skin samples from nesting turtles to get clues about their feeding habits
      . Depending on where and what turtles eat, they pick up different chemical signatures called isotopes. Scientists identify the isotopes (carbon and nitrogen atoms with differing numbers of neutrons) in skin samples and pair those results with satellite-tagging data on where turtles traveled. This helps to pinpoint the feeding grounds where turtles go between nesting years and helps the scientists link other turtles to those feeding grounds via skin samples, without expending the additional time and resources to satellite tag them all. By identifying feeding grounds and showing how many turtles use them, this research informs efforts to protect turtles and their habitats.
       
    • One big turtle family? Maybe not!

      Mote scientists are providing genetic samples from loggerhead and green sea turtles in southwest Florida to partners at the University of Georgia (UGA) who study the genetic relationships among sea turtles at different nesting beaches. Their goal: Investigate how genetically similar (closely related) nesting turtles are on our beaches and determine how these nesters relate to other Gulf of Mexico nesting populations. If turtles are clumped into distinct genetic groups, then protecting habitat and food resources used by one group will not necessarily help the others. So far, UGA research supports the idea that Florida loggerheads form several distinct groups that conservation and management plans should account for. Mote scientists are currently collecting samples to apply the same research tools to the growing green sea turtle population along with hybrid turtles resulting from mating between different species.
       
    • Deep dive into turtle data

      Mote scientists at STCRP have monitored and studied nesting sea turtles for nearly four decades in southwest Florida, documenting the trend of increasing nest counts for loggerheads and greens since 2008. Now, they’re undertaking a deeper dive into Mote’s decades of data to learn even more. They’re investigating nesting success (how many of the turtles that crawl ashore leave a nest vs. return to sea without nesting), along with the success rates of nests hatchling and hatchlings emerging, using data from Mote’s morning Sea Turtle Patrol to help assess how productive local nesting beaches are in relation to the rest of the Gulf of Mexico. Using Mote’s data from tagged turtles, the team is also assessing the turtles’ remigration intervals (how long it takes them to return for another nesting season), how frequently they lay new nests within a season, and how many females are in the population.

      Mote's sea turtle activities are conducted under Florida Fish and Wildlife Conservation Commission Marine Turtle Permits 027, 054, 070, 048, 028, 155, and 216.

MARINE MAMMAL SCIENCE ADDS UP

  • Manatee research by the (record) numbers
     
    • Mote scientists counted 185 manatees in Sarasota County waters—a local record number for the second year in a row—on June 24, 2020 via aerial (airplane) surveys. Sarasota County surveys are funded through a grant from the County’s West Coast Inland Navigation Program. Mote staff also counted a record high number of manatees at a warm-water site located off the Indian River Lagoon, where a minimum of 2,500 manatees were observed. The 2019-2020 winter season marks the 43rd year of winter surveys around selected power plants other winter habitats to count manatees; Mote scientists have been involved for most of that span. These surveys are funded by Florida Power & Light Co. (FPL). 
       
    • To advance a study originally launched in 2019, Mote scientists conducted their fifth survey to investigate whether unmanned aerial vehicles (UAVs, drones) with video cameras may enhance manatee surveys for numbers, distribution and possibly identification of some individuals, without disturbing the manatees. This year’s new survey once again recorded high-quality video of manatees at two sites surveyed in January 2020. Two or three more surveys are planned at each test site before completing the study, which is funded by FPL.
       
    • This year in southwest Florida, Mote scientists conducted 271 photo-identifications surveys identifying 342 individual manatees. Of those, 97 have been observed repeatedly and four have been observed for 37 years. Mote scientists also documented 11 mating herds (multiple male manatees attempting to mate with a female in estrus) or escort herds (before mating attempts begin) in southwest Florida. Mote scientists to collect data on each mating/escort herd, educate the public and monitor/limit their interactions with the manatees to protect both the animals and onlookers.
       
      • A pregnant manatee that Mote helped to rescue this year, nicknamed “Siesta,” was matched to scientific records through photo identification. She was first encountered by Mote in September 2016 in Pansy Bayou and for the second time in June 2018 in the grass flats at City Island, Sarasota.
         
    • On Florida’s west coast, Mote scientists identified two manatees previously seen on Florida’s east coast. One was first observed in Miami and re-sighted this year in Fort Myers. The other was first observed in Fort Lauderdale and re-sighted this year in Palma Sola Bay. It’s important to understand where and how far manatees can travel to support management of their populations.
       
    • Mote scientists also made significant progress with photo-identifying manatees and collecting water temperature data for an ongoing study that launched in October 2018. The study investigates how manatees respond to the temporary disruption of a warm-water source during the modernization of FPL’s Lauderdale Plant in Dania Beach, Florida. During the study’s second year, Mote scientists photo-documented more than 400 distinctive manatees, including individuals known to scientists for as long as 42 years. Of those, 66 individuals have been identified through searches of the statewide database, the Manatee Individual Photo-identification System (MIPS), with past sightings ranging from Georgia to the Florida Keys.

      Florida manatees seek warm water refuges when temperatures drop below approximately 68 degrees Fahrenheit, their threshold of cold tolerance. Manatees exposed to cold temperatures for too long are at risk for cold stress syndrome, one of the major challenges facing these threatened mammals. Cold stressed manatees can develop a variety of severe symptoms, including but not limited to immune suppression, lesions of the heart, skin and other organs, pneumonia and systemic infection, which can lead to death.
       
    • While COVID-19 precautions have delayed some aspects of manatee research in the environment, Mote scientists collected valuable new data on manatees’ temperature profiles during November 2019 in Belize. There, Mote scientists were part of a team effort to capture and release Antillean manatees, the smaller of two subspecies of West Indian manatees (the other subspecies is the Florida manatee) for health assessments. This effort allowed Mote scientists to measure the Antillean manatees’ skin temperature and compare it with previous temperature measurements in Florida manatees, including Hugh and Buffett, two resident Florida manatees at Mote Aquarium.

      As with all Sirenians (manatees and dugongs) living on Earth today, Antillean manatees are listed as Vulnerable by the IUCN. Antillean manatees live in the year-round warm Caribbean waters, which reduces their risk of cold stress significantly. Contrarily, in summer, Antillean manatees need to find ways to cool down, as temperatures in the shallow lagoons at the coast of Belize can reach and exceed 100 degrees Fahrenheit.

      In contrast to the well-studied Florida manatees, scientific knowledge about Antillean manatees is sparse. Comparative studies in these two subspecies enhance knowledge and inform the conservation of the less-known Antillean manatee, while providing valuable insight into manatee thermal biology in general—including the impact of high water temperatures on manatee physiology. Mote scientists hope to continue investigating Antillean manatees as COVID-19 conditions allow.
       
  • Sarasota Dolphin Research Program celebrates 50th anniversary:

    In 2020, the Sarasota Dolphin Research Program (SDRP) celebrated its 50th year of research, conservation, and education activities to benefit cetaceans (dolphins and whales) in Sarasota Bay, Florida, and around the world. The SDRP, a Chicago Zoological Society Program in collaboration with Mote, conducts the world’s longest-running study of a wild dolphin population. Five decades of research on Sarasota Bay’s long-term, year-round resident community of individually identifiable bottlenose dolphins established the location as a unique natural laboratory for learning about dolphin biology, behavior, ecology, health and communication, as well as human impacts to them. The Sarasota dolphins attract researchers and students from around the world to address questions that are impossible to answer elsewhere in the absence of such detailed background information.

    Here are just a few highlights from SDRP’s research over 50 years:
     
    • SDRP has discovered dolphins up to 67 years of age, spanning as many as five concurrent generations, living in an area where the human population and numbers of boats have quadrupled over the past five decades. Identifying dolphin responses to human activities and environmental changes is necessary for providing appropriate and adequate protection measures.
       
    • Findings from Sarasota Bay dolphins have been used to inform protection efforts and to understand the plights of dolphins in more at-risk populations elsewhere in the U.S. NOAA has used SDRP findings to improve their protective measures for bottlenose dolphins throughout the southeastern part of the country and used Sarasota dolphins as a reference population for comparisons with more at-risk populations to identify and define impacts of natural and human-caused phenomena such as the Deepwater Horizon oil spill and red tides (harmful algal blooms).
       
    • 43 doctoral dissertation and 41 master’s thesis projects have benefited from association with SDRP through field research opportunities or access to data, samples, or guidance from staff. More than 430 undergraduate interns have received training since 1991.
       
    • SDRP staff has provided training opportunities for more than 100 researchers and students from more than 30 countries in dolphin research techniques that are now being applied to species of conservation concern around the globe.
       
    • SDRP staff members have been involved as senior authors or co-authors for four books, more than 270 peer-reviewed journal articles and book chapters.
       
    • And above all, SDRP scientists have learned a great deal about Sarasota Bay dolphins. Their society, though generally composed of fluid groupings within a resident community, includes complex and long-lasting associations such as strongly bonded male pairs and extended associations of mothers and calves well beyond nutritional weaning, showing indications of cultural transmission of knowledge. The program team has learned—and shared with the world—that these dolphins are truly our neighbors, and what we do to the neighborhood affects them as well as us.