Male loggerhead turtles also go back to nesting beaches

This 2014 video says about itself:

Loggerhead Sea Turtle Hatchling Rescue!!!

Words cannot describe…

I came across some baby sea turtle tracks one morning at the refuge and noticed many of the tracks went up into the dune instead of directly to the water. A quick search revealed several hatchlings floundering in the dune vegetation. As the acting refuge biologist, I am permitted to handle these protected turtles for purpose of rescue. This was an amazing opportunity for me to examine these amazing creatures up close and personal, a rare and priceless occurrence.

These animals are protected, please do not approach them in the wild.

From the Universidad de Barcelona in Spain:

Male loggerhead turtles also go back to their nesting beaches to breed

March 14, 2018

Most male loggerhead turtles go back to the nesting beaches to breed -a common behaviour among female turtles-, according to a study in which the researchers Marta Pascual, Àlex Aguilar, Carles Carreras, Lluís Cardona and Marcel Clusa, from the Faculty of Biology and the Biodiversity Research Institute of the University of Barcelona (IRBio) took part.

Also, experts from the Cyprus Wildlife Society (Cyprus), University of Tripoli (Libya) and the University Adnan Menderes (Turkey), among other institutions, collaborated in the study.

The study, published in the journal Marine Ecology Progress Series, outbreaks the classical view on the breeding behaviour of these marine turtles, and explains how the species could also breed in feeding areas or during their journey towards nesting beaches.

New paradigm: male turtles return to the nesting beach to breed

The loggerhead turtle (Caretta caretta) is a marine species that travels long journeys to tropical and temperate areas around the world. In the eastern Mediterranean, in particular, it nests in the coasts of Greece, Turkey, Cyprus, Libya, Lebanon and Israel, although there have been some sporadic nesting episodes in the western Mediterranean.

It was believed that only female turtles went back to the nesting areas to lay the eggs –philopatric behaviour- after reproducing with male turtles from different areas. Philopatry is a studied phenomenon among female C. caretta turtles. The process of detection, marking, and the chelonian genetic study (for instance, with the mitochondrial DNA, transmitted by maternal inheritance), are easily conducted if females are the ones that go back to the beach of birth to lay the eggs.

However, markers in males are not abundant and results have never been conclusive. Previous studies with few genetic nuclear markers ─microsatellite loci, the biparental inheritance─ suggested male turtles did not show philopatric behaviour and mated with females from different areas.

“Our study reveals the breeding behaviour of the C. caretta marine turtle can be more complex. In most populations, female turtles are not the only ones with philatropic behaviour: males also mate near nesting beaches”, says the lecturer Marta Pascual, member of the Department of Genetics, Microbiology and Statistics of the UB and IRBio.

Breeding far from nesting beaches

In the study, the UB-IRBio team increased the number of microsatellite markers to analyse the gene flow among loggerhead turtle populations in the Mediterranean. The results show a higher gene differentiation in the nesting beaches in the Mediterranean and suggest the possibility that turtles breed in feeding areas or during their journey towards nesting beaches.

“Therefore, the accepted belief that males do not display philopatry could be due -in some cases- the low number of molecular markers that were used so far”, states Marta Pascual. “Also, if we compare mitochondrial and nuclear markers, we can compare the spreading behaviour of male and female turtles in different areas, which shows complex and particular breeding behaviours in each area.”

Higher temperatures, more female turtles in the marine habitat

In most cases, philopatry happens in male and female turtles. However, there are cases of opportunistic breeding patterns between males and females in different areas other than their place of birth. According to the experts, the obtained results could be explained with some hypotheses that have to be tested in future studies.

“The breeding behaviour can change depending on the population; it can even be affected by the amount of male turtles that are born in a specific area,” says Pascual. The sex of marine turtles is determined by the temperature of incubation. If the temperature is high, there will only be female turtles: “with global warming, high temperatures would cause a feminization of the populations, a phenomenon that could be balanced through opportunist breeding with males from other areas”, concludes the expert.

Protecting an emblematic species in the Mediterranean

Although the Mediterranean can be understood as a regional unit to manage globally, when it comes to the loggerhead turtle there are genetically differentiated units that should be protected. In some cases, these are big populations -according to the annual number of nests in their beaches- but there are examples that show a lower balance. In a planet affected by global change, a more comprehensive study of different areas is necessary to identify bottlenecks -which reduce the number of population individuals- and to study the impact of the increase of consanguinity over the viability of the different units.

There are still many unknown issues on the breeding biology of the species C. caretta. Migratory routes that have been observed with telemetry on females in Cyprus show that they feed in Libya and travel near this area’s nesting beaches. New studies with genomic scale markers are necessary to get deeper in the biology and ecology of the most abundant marine turtle in the Mediterranean (sporadic nesting, non-philopatric breeding, etc.).


How turtles got their shells, video

This video from the USA says about itself:

How the Turtle Got Its Shell

12 March 2018

Where did turtles come from? And how did the they get their shells? The answers to these questions would eventually cause scientists to rethink the entire history of reptile evolution.

African tortoise survives elephants

This video from South Africa says about itself:

World’s Luckiest Tortoise Survives Elephant Stampede!

6 March 2018

Saved by the bell, or in the animal kingdom, it is more like saved by your shell.

Watch the dramatic moment a tortoise finds himself between the feet of a thirsty herd of elephants that is on its way down to the waterhole.

The sighting starts off with a lone tortoise down by the water, quenching his thirst. Suddenly, viewers could start hearing a bit of a rumble coming from the area and the tortoise immediately went into his shell before the rowdy crowd came along.

A thirsty herd of elephants in the Pilanesberg strolled down to the watering hole for a drink from the Kwa Maritane lodge. Interestingly enough, the elephants seemed to be aware of the tortoise’s presence and were very careful to step over the tortoise or only bump him gently with their giant feet. Everyone watching was just waiting for the unfortunate moment that one elephant didn’t see this unusual “rock” and steps right onto it. But it miraculously didn’t happen! For a minute or so, the herd was standing over the tortoise, having a good time in the water! But luckily, the elephants soon moved a bit upstream and the tortoise immediately saw an escape path, letting him flee for his life back to the safety of the surrounding bush.

Studying sea turtles with drones

This video from Costa Rica says about itself:

Drone Video of Leatherback Sea Turtle Returning to Sea After Nesting

21 March 2017

Playa Grande, the largest of the beaches in Las Baulas National Park, is not only well known for surf breaks and stunning sunsets but also for visits from nesting turtles like this leatherback sea turtle.

Playa Grande, Playa Ventanas and Playa Langosta, are all part of Las Baulas National Park (Parque Nacional Marino Las Baulas). The Park protects one of the most important nesting beaches for the East Pacific leatherback turtle, a population designated as critically endangered by the International Union for Conservation of Nature (IUCN). Park Rangers, local guides, members of local communities, researchers and volunteers are working hard to save these turtles from extinction, as well as to protect the local wildlife and flora.

From the University of Exeter in England:

Stunning footage shows how drones can boost turtle conservation

February 28, 2018

Drones are changing the face of turtle research and conservation, a new study shows.

By providing new ways to track turtles over large areas and in hard-to-reach locations, the drones have quickly become a key resource for scientists.

The research, led by the University of Exeter, also says stunning drone footage can boost public interest and involvement in turtle conservation.

“Drones are increasingly being used to gather data in greater detail and across wider areas than ever before”, said Dr Alan Rees, of the Centre for Ecology and Conservation on the University of Exeter’s Penryn Campus in Cornwall.

“Satellite systems and aircraft transformed turtle conservation, but drones offer cheaper and often better ways to gather information.

“We are learning more about their behaviour and movements at sea, and drones also give us new avenues for anti-poaching efforts.”

The paper warns that, despite the benefits, drones cannot fully replace ground work and surveys.

And it says more research is required to understand if and how turtles perceive drones during flight, and whether this has an impact on them.

That is a lot better use of drones than using them for killing civilians.

Fossil turtle discovery in Tennessee, USA

This video from the USA says about itself:

22 February 2018

Earlier this February (2018) a research paper was put out by Steven E Jasinsky describing a new species of ancient turtle discovered at the Gray Fossil Site in East Tennessee. This turtle in particular was named after our lab and field manager Shawn Haugrud. Here he is presenting a few specimens of this fossil.

From the University of Pennsylvania in the USA:

Fossil turtle species, 5.5 million years old, sheds light on invasive modern relatives

February 26, 2018

A University of Pennsylvania paleontologist has described a 5.5 million-year-old fossil species of turtle from eastern Tennessee. It represents a new species of the genus Trachemys, commonly known as sliders, which are frequently kept as pets today.

Steven Jasinski, author of the new study, is a doctoral student at the University of Pennsylvania and acting curator of paleontology and geology at the State Museum of Pennsylvania. He is completing his Ph.D. at Penn under Peter Dodson, a professor of paleontology in the Department of Earth and Environmental Science in the School of Arts and Sciences and a professor of anatomy in the School of Veterinary Medicine.

The study investigated a fossil turtle found around the Miocene-Pliocene boundary in the Gray Fossil Site, an area rich with fossils in eastern Tennessee near East Tennessee State University, where Jasinski completed his master’s degree. The site represents an ancient sinkhole surrounded by a forest from which dozens of fossil animal species have been characterized, including new species of red panda, Eurasian badger, kinosternid turtle, and colubrid snake.

Thorough examination of the dozens of turtle fossils from the site revealed important differences between this turtle and other known fossil and living species. Jasinski named the fossil turtle Trachemys haugrudi, after Shawn Haugrud, the lab and field manager and lead preparer at the Gray Fossil Site.

“Shawn has spent an incredible number of hours working on these specimens”, Jasinski said. “He cleaned and prepared the fossils and was able to essentially glue this turtle back to life, giving me numerous nearly complete turtle shells to use in this research. Without all that time and effort, I wouldn’t have been able to determine nearly as much about this turtle as I did.

“Shawn also didn’t do this work alone, as numerous other people including volunteers worked on these fossils and got them prepared so that I could complete my research. They really did all the hard work, and I was then able to determine why it was new and what its implications are” he said.

Turtles are best known for their shells, and indeed it is this feature of their anatomy that is commonly found as fossils. Yet the fossil shells are typically found in broken pieces. Often gaps or holes remain, or only single small pieces are found, and the whole must be inferred from other information, including other fossil and living creatures.

“It is extremely rare to get more complete fossils”, Jasinski said, “but Trachemys haugrudi, commonly called Haugrud’s slider turtle, provides me with dozens of shells, and several are nearly complete.”

Haugrud’s slider turtle was a fairly small turtle, not more than approximately 10 inches (25 cm) in total shell length, smaller than the modern-day red-eared slider turtle, Trachemys scripta elegans. Red-eared slider turtles are commonly purchased as pets, though they can grow large, and some owners release them into the wild. As a result, though native to the southeastern United States, red-eared sliders have become one of the most invasive animal species in the world today, found on every continent except Antarctica.

“People tend to see all turtles as similar and release them into whatever pond or river is close by when they no longer want to care for them”, Jasinski said. “Once released, however, they often outcompete native species. It is a problem that scientists are still dealing with.”

As part of the study, Jasinski sought to determine where Trachemys haugrudi was positioned in the evolution of similar turtles both within the genus and in related genera. He performed a phylogenetic analysis, a method that compares shapes and features of different species to determine how similar or dissimilar and therefore how closely related they may be. He found Haugrud’s to be most closely related to a group of fossil Trachemys turtles from Florida and next most closely related to a distinct group of fossil Trachemys from the midwestern U.S. Together, these fossil Trachemys form a closely related group situated within other still-living species of Trachemys.

Today, distinct, closely-related groups of Trachemys species dwell in Mexico, Central and South America, and the Caribbean. Jasinski’s investigation, along with other information from previous studies, indicates that one group evolved in Mexico and Central and South America and evolved into different species within this geographic area, and another group evolved separately in the Caribbean.

Species from the U.S., including the red-eared slider turtle, are found near the base of their “branch” of the Trachemys family tree; their fossil ancestors are still waiting to be discovered. The fossil Trachemys species in Jasinski’s analysis are on a distinct part of the Trachemys tree, and current understanding suggests that they did not give rise to the modern species living today.

The findings imply that there was once much greater diversity in Trachemys turtles than exists today. It seems that many of the ancient slider species died out without leaving any direct descendents, perhaps because they lacked the ability to adapt to different environments.

“While Trachemys turtle species are considered plastic, implying they can adapt to and live in many environments, this adaptive lifestyle may be a relatively newer characteristic of these turtles”, Jasinski said. “More fossils are needed to better understand if this aspect of their evolution is a recent addition.”

To get a handle on invasive turtles, understanding more about their ancient relatives could only be helpful, Jasinski said.

“Trachemys haugrudi helps provide more information on Trachemys and begins to offer us insights into the evolution of an animal that has become a problematic invader in many areas of the world”, he said. “Understanding how something evolved into its present form may help us understand why an animal is so adaptive and good at invading new areas and outcompeting native species. If we can see that Trachemys today are especially adaptive because evolution has allowed them to become more generalized through time, we can use that information to determine where they may invade, what species they may outcompete and what we can do to counteract those invasions or help native species compete against them.”

Jasinski is undertaking further study into the fossil species of not only Trachemys but other turtles within the family Emydidae, which includes Trachemys. He hopes that further data and fossils will help shed light on other turtle species and provide a clearer understanding of the evolution of this group of mainly New World turtles.

The study was supported by the National Science Foundation (Grant 0958985 to Steven Wallace and the Gray Fossil Site), Office of Research and Sponsored Programs at East Tennessee State University, Don Sundquist Center of Excellence in Paleontology, State Museum of Pennsylvania, and Department of Earth and Environmental Science at the University of Pennsylvania.

Marine animals, new studies

This video says about itself:

Australian turtle tracking aids understanding and conservation – Science

17 April 2015

Marine turtles are among the most endangered species on the planet. In an attempt to assist in the preservation of these unique creatures, researchers at the James Cook University in Australia are involved in a project to track the movements of baby flatback turtles.

To follow the turtles as they navigate the Great Barrier Reef scientists fix a GPS tracking device, weighing 100 grammes to the young reptiles.

The turtles are then released into the ocean and monitored by the research team.

Read more here.

From the University of California – Santa Cruz in the USA:

Tracking data reveal the secret lives of marine animals

Seals, whales, sharks, turtles, seabirds, and other marine vertebrates show similar patterns of movement in marine environments

February 26, 2018

The movements of marine mammals and other large animals that spend their lives in the ocean were largely unknown prior to the development of sophisticated tracking devices researchers could deploy on animals in the wild. Insights gained from this technology have revealed unexpected behaviors and migratory patterns in marine animals ranging from sharks and seals to turtles and albatrosses.

Researchers from around the world have now pooled their data on the movements of a wide array of marine animals, enabling them to look for common features in how animals move throughout the world’s oceans. The results, published February 26 in Proceedings of the National Academy of Sciences, show remarkable convergence in the movement patterns of different species, even those widely separated by geography, phylogeny (evolutionary history), or mode of travel.

The biggest differences were between different habitats rather than between different species. In coastal areas, tracking tags revealed complex movement patterns dominated by search behavior, while in the open ocean they showed simpler, more predictable movements over longer distances.

“It makes sense, because the coast is a much more complicated environment, whereas the open ocean is more homogeneous and the features are more spread out in space and time,” said coauthor Daniel Costa, a distinguished professor of ecology and evolutionary biology at UC Santa Cruz. “Regardless of what species it is, the movement patterns match the oceanographic features of their environment.”

These insights can be useful, he said, for understanding how marine life will respond to climate change and for predicting the movements of species for which tracking data are lacking. “Many of these species are endangered and we have no tracking data, but we can extrapolate from other species to understand how they are likely to interact with fisheries, shipping, or other human activities”, Costa said.

Costa has been at the forefront of developing high-tech tracking devices and using them to study marine animals. UCSC’s Long Marine Laboratory is known as a leading center for research on marine vertebrates, including seals, sea lions, sea otters, dolphins, and whales. The coauthors of the PNAS paper include six other UC Santa Cruz researchers in addition to Costa.

“This paper is the result of a big international effort. We realized that if we all share our data and work together in a concerted manner, we can learn a lot more about these animals,” he said.

Costa and other UCSC researchers deployed the first satellite tracking tags on elephant seals at the Año Nuevo rookery north of Santa Cruz in the 1990s. The initial results were astonishing.

“Before we put tags on elephant seals, all the books said they were limited to the California Current. We had no idea they were traveling these incredible distances and using the entire North Pacific Ocean“, Costa said. “We went from studying them where we could watch them to having the animals tell us where they were going.”

In 2000, Costa joined forces with Barbara Block at Stanford University and others to launch the Tagging of Pacific Predators (TOPP) program, a decade-long effort to track the movements of top marine predators in the Pacific Ocean. Costa oversaw the tracking of marine mammals, birds, and turtles for TOPP, which also included tracking of sharks and tunas.

Costa’s lab has carried out groundbreaking tracking studies of a wide range of species around the world, including albatrosses, sooty shearwaters, California sea lions, Galapagos sea lions, crabeater seals, Weddell seals, and southern elephant seals. Meanwhile, his team has continued to learn new things about elephant seal biology from ongoing studies of the northern elephant seals at UC’s Año Nuevo Natural Reserve.

One recent study, published February 14 in Biology Letters, revealed the effects of pregnancy on the diving behavior of female elephant seals. Led by postdoctoral researcher Luis Huckstadt, the researchers found that the dives of pregnant seals became shorter, probably due to an increasing demand for oxygen for the fetus.

“The only way we could do that is because we now have over 500 tracks of female elephant seals, and a small number of them didn’t have a pup or lost it at sea, so we could compare and see the effects of pregnancy. It’s not surprising, but nobody had been able to document it,” Costa said.

Saving sick sea turtles

This video from the USA says about itself:

Sea Turtles Get Life-Saving Surgery at Florida Hospital | National Geographic

6 February 2018

The Turtle Hospital, a care and rehab center in the Florida Keys, has performed a recently developed treatment on two green sea turtles—an encouraging step in their fight against a pandemic disease.