Pacific island Vatuvara wildlife survey


This 2017 video from Fiji is called Vatuvara Private Islands.

From BirdLife:

22 Nov 2017

Exploring the untouched island of Vatuvara

This is the first time a full biological survey has ever been performed on this remote, almost untouched island in the South Pacific. The intriguing and fascinating results have redoubled the Vatuvara Foundation’s efforts to safeguard this lush wildlife haven.

By Steve Cranwell

The island of Vatuvara perfectly embodies the intrigue and beauty of the South Pacific islands. Located in the north of Fiji’s Lau group, the 800-hectare island has been uninhabited for most of human history. This is due in part to the absence of a permanent water source – but the sharp, unforgiving coral terrain certainly doesn’t help.

For a time, the island hosted a fortified village atop the 300-metre summit – no doubt a strategic lookout point for Fijian warriors. But apart from a desperate attempt at coconut production during Fiji’s plantation era, Vatuvara has largely been spared the impacts of human influence. And that includes many invasive species common on other South Pacific islands – making Vatuvara an invaluable refuge for wildlife.

Despite the detailed knowledge of the indigenous Fijians, practically the only formal scientific account of the island comes from the remarkable Whitney Expeditions, which visited Fiji in 1924, identifying the endemic Fiji Banded Iguana Brachylophus fasciatus among other native flora and fauna species.

Now under the care of Vatuvara Private Islands, the island is protected as a nature reserve. In November, BirdLife International Pacific, together with NatureFiji-MareqetiViti (BirdLife in Fiji) and the US Geological Survey, joined the Vatuvara Foundation to conduct a pioneering four-day survey.

The survey initially focused on the island’s reptiles, in particular the Banded Iguana – currently threatened with extinction – and a snake, the Pacific Boa Candoia bibroni. During the night, several sleeping reptiles were stealthily extracted from the branches above for identification.

Coconut crabs Birgus latro proved to be a very visible part of the island fauna. Although active throughout the day, it was at night that the forest came alive to a slow, deliberate dance as the world’s largest arthropods (weighing up to 4kg and a metre from leg to leg) shuffled about the forest floor, or climbed trees and vertical rock faces in search of sustenance. Once common throughout the Pacific and Indian Oceans, these unique, long lived terrestrial crabs, who can survive for 40-60 years, are under threat. Considered a local delicacy, crab populations are now increasingly confined to remote inaccessible islands or locally protected areas.

Vatuvara is an island for birds. Dawn and dusk resounded to a cacophony of calls as the Wattled Honeyeater Foulehaio carunculatus, along with the 20 other species we identified, made their presence known. Almost all were forest birds, a validation of the quality of Vatuvara’s forest. A particularly encouraging sighting was the Shy Ground Dove Alopecoenas stairi, threatened with extinction elsewhere due to introduced predators such as feral cats and rats.

In terms of invasive species, no evidence of cats, pigs, goats, Black rats Rattus rattus, mongoose, invasive ants or any of Fiji’s usual suspects could be found. However, the Pacific rat Rattus exulans was present. This non-native rat predates small birds and their eggs, as well as many of Fiji’s invertebrates and fauna.

All good surveys pose as many questions as they answer, and something of a surprise for Vatuvara was the notable absence of seabirds, generating numerous hypotheses, including what influence Coconut Crabs may pose. Ornithologist Vilikesa Masibalavu also noted an unusual phenomenon among the Island’s Fiji Whistlers Pachycephala vitiensis. They weren’t hard to find – but they were strangely silent, and not a single male could be found.

While much still remains to be discovered on Vatuvara, the survey highlighted the Island’s vital importance to Fiji’s natural history. It was found to hold a wealth of diverse native plants and wildlife increasingly under threat on other islands. Future work will build on this baseline, tracking trends in birds, coconut crabs and reptiles and ensuring harmful invasive species don’t establish. In protecting the island, the Vatuvara Foundation have made a visionary commitment to safeguarding a crucial haven for Fiji’s wildlife.

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Longest sauropod dinosaur trackway discovery


This video says about itself:

3 September 2012

Huge sauropods’ footprints from the late Jurassic plus tridactyls’ trackways – Plagne, French Jura…150 millions years ago!

From CNRS in France:

World’s longest sauropod dinosaur trackway brought to light

November 13, 2017

In 2009, the world’s largest dinosaur tracks were discovered in the French village of Plagne, in the Jura Mountains. Since then, a series of excavations at the site has uncovered other tracks, sprawling over more than 150 meters. They form the longest sauropod trackway ever to be found. Having compiled and analyzed the collected data, which is published in Geobios, scientists from the Laboratoire de Géologie de Lyon (CNRS / ENS de Lyon / Claude Bernard Lyon 1 University), the Laboratoire Magmas et Volcans (CNRS / Université Clermont Auvergne / Université Jean Monnet / IRD), and the Pterosaur Beach Museum conclude these tracks were left 150 million years ago by a dinosaur at least 35 m long and weighing no less than 35 t.

In 2009, when sauropod tracks were discovered in the French village of Plagne — near Lyon — the news went round the world. After two members of the Oyonnax Naturalists’ Society spotted them, scientists from the Paléoenvironnements et Paléobiosphère research unit (CNRS / Claude Bernard Lyon 1 University) confirmed these tracks were the longest in the world. Between 2010 and 2012, researchers from the Laboratoire de Géologie de Lyon supervised digs at the site, a meadow covering three hectares. Their work unearthed many more dinosaur footprints and trackways. It turns out the prints found in 2009 are part of a 110-step trackway that extends over 155 m — a world record for sauropods, which were the largest of the dinosaurs.

Dating of the limestone layers reveals that the trackway was formed 150 million years ago, during the Early Tithonian Age of the Jurassic Period. At that time, the Plagne site lay on a vast carbonate platform bathed in a warm, shallow sea. The presence of large dinosaurs indicates the region must have been studded with many islands that offered enough vegetation to sustain the animals. Land bridges emerged when the sea level lowered, connecting the islands and allowing the giant vertebrates to migrate from dry land in the Rhenish Massif.

Additional excavations conducted as late as 2015 enabled closer study of the tracks. Those left by the sauropod’s feet span 94 to 103 cm and the total length can reach up to 3 meters when including the mud ring displaced by each step. The footprints reveal five elliptical toe marks, while the handprints are characterized by five circular finger marks arranged in an arc. Biometric analyses suggest the dinosaur was at least 35 m long, weighted between 35 and 40 t, had an average stride of 2.80 m, and traveled at a speed of 4 km/h. It has been assigned to a new ichnospecies1: Brontopodus plagnensis. Other dinosaur trackways can be found at the Plagne site, including a series of 18 tracks extending over 38 m, left by a carnivore of the ichnogenus Megalosauripus. The researchers have since covered these tracks to protect them from the elements. But many more remain to be found and studied in Plagne.

1 The prefix ichno- indicates that a taxon (e.g., a genus or species) has been defined on the basis of tracks or other marks left behind, rather than anatomical remains like bones.

Alligator snapping turtles back in Illinois, USA


This 2015 video from the USA is called Alligator Snapping Turtle vs Common Snapping Turtle.

From the University of Illinois at Urbana-Champaign in the USA:

First wild alligator snapping turtle in Illinois since 1984

November 13, 2017

Researchers report the first sighting in 30 years of a wild alligator snapping turtle in Illinois. The discovery may be a sign of hope for this state-endangered species, or the animal could be the last of its kind to have survived in Illinois without human intervention, the researchers say.

The team reports the find in the journal Southeastern Naturalist.

In October 2014, when Illinois Natural History Survey herpetologist Chris Phillips donned a wetsuit and dove to the bottom of Clear Creek in Union County, Illinois, he was looking for a young male alligator snapping turtle with a radio transmitter on its back. That turtle had recently been released in the area to bolster the state-endangered turtle population in southwest Illinois.

“I was just about out of breath when I felt the turtle shell,” Phillips said. “I thought I had found the male turtle I knew was there because I detected its radio signal. I felt along its back to where I thought the shell should end, but my hand just kept going.”

Phillips plucked from the water a 22-pound, 15-inch long female alligator snapping turtle that was twice as long as the one he was looking for, and at least 18 years old. Since she had no tracking device, she was not one of the turtles that had been released into the area. DNA tests showed that she belonged at the site and was not a lone traveler from a southern state. Southern Illinois is at the northern end of the turtle species’ range.

For years, INHS researchers have conducted extensive trapping, and have called for citizen observations along Clear Creek for signs of wild alligator snapping turtles, but to no avail. Populations of this state-endangered species have declined because of habitat changes including dams, drained swamps and river dredging. Only Union and Jackson counties offer the habitat that the turtles need to reproduce and thrive. Locating any wild turtles in these counties will help determine the next steps — whether to preserve a population or reintroduce more alligator snapping turtles in Illinois.

“Bolstering a hidden population of an endangered species is better than starting a new population in the area,” said Ethan Kessler, a graduate student of natural resources and environmental sciences at the University of Illinois and a co-author of the study. “However, since no wild alligator snapping turtles have been found in Illinois since 1984, reintroduction efforts make sense.”

For several years, researchers have purchased turtles reared in a facility and released them at ages 2, 3, 4, 5 or 6. They also released about 90 adult turtles. Most of the animals go into creeks with radio transmitters attached to their backs so they can be relocated and tracked.

Researchers were conducting their biannual catch-and-release program when they found the wild turtle, close to the same spot and 30 years, almost to the day, after their last wild alligator snapping turtle was found.

“Finding this individual does not indicate that there is a functional, stable population of wild alligator snapping turtles in Southern Illinois,” Kessler said. “When a population dies out, a single turtle may wander around like a zombie waiting for the end of its days.”

Alligator snapping turtles can live 100 years, so the researchers working on this project today likely will not witness the advancing seasons of this female’s life. After finding her, the team marked her shell with a notch and attached a radio transmitter to her back for tracking. The transmitter battery died, however, and finding her again in the sediment-filled depths of Clear Creek or elsewhere would be like finding a needle in a haystack, Phillips said.

“She is marked, so in case of an incidental encounter, we will know it’s her,” he said.

One of the challenges of tracking turtles that have been introduced in Illinois is that they disappear underwater and may not be seen again until divers retrieve them.

“If we succeed with our project in introducing a new, viable population of alligator snapping turtles, it’s likely that no one will see them,” Phillips said. “It’s not as if we’re studying bald eagles that soar above us. I may never know the fate of these turtles, but it’s cool to know that this wild space exists in Illinois.”

The alligator snapping turtle is listed as threatened in the U.S.

The Illinois Department of Natural Resources funded this research. Mike Dreslik of the INHS and Scott Ballard of IDNR are co-authors of the article. The INHS is a division of the Prairie Research Institute at the University of Illinois.

‘Crocodiles, not Stone Age humans, killed animals’


This video says about itself:

10 November 2009

Paul Sereno and his team of scientists and artists show us what the world looked like in an age when crocs ate dinosaurs.

By Bruce Bower, 3:16pm, November 6, 2017:

Crocs take a bite out of claims of ancient stone-tool use

Scars left on bones could have come from hungry reptiles instead of Stone Age butchery, researchers say

Recent reports of African and North American animal fossils bearing stone-tool marks from being butchered a remarkably long time ago may be a crock. Make that a croc.

Crocodile bites damage animal bones in virtually the same ways that stone tools do, say paleoanthropologist Yonatan Sahle of the University of Tübingen in Germany and his colleagues. Animal bones allegedly cut up for meat around 3.4 million years ago in East Africa (SN: 9/11/10, p. 8) and around 130,000 years ago in what’s now California (SN: 5/27/17, p. 7) come from lakeside and coastal areas. Those are places where crocodiles could have wreaked damage now mistaken for butchery, the scientists report online the week of November 6 in the Proceedings of the National Academy of Sciences.

Larger samples of animal fossils, including complete bones from various parts of the body, are needed to begin to tease apart the types of damage caused by stone tools, crocodile bites and trampling of bones by living animals, Sahle’s team concludes. “More experimental work on bone damage caused by big, hungry crocs is also critical,” says coauthor Tim White, a paleoanthropologist at the University of California, Berkeley.

In a field where researchers reap big rewards for publishing media-grabbing results in high-profile journals, such evidence could rein in temptations to over-interpret results, says archaeologist David Braun of George Washington University in Washington, D.C., who did not participate in the new study or the two earlier ones. “There’s a push to publish extraordinary findings, but evolutionary researchers always have to weigh what’s interesting versus what’s correct.”

Authors of the ancient butchery papers agree that bone marks made by crocodiles deserve closer study and careful comparison with proposed stone-tool marks. But the researchers stand their ground on their original conclusions.

Microscopic investigations in the 1980s led some researchers to conclude that carnivores such as hyenas leave U-shaped marks on bones. In contrast, they argued, stone tools leave V-shaped incisions with internal ridges. And hammering stones create signature pits and striations.

Sahle’s group expanded on research previously conducted by paleoanthropologist Jackson Njau of Indiana University Bloomington. In his 2006 doctoral dissertation, Njau reported that bone damage produced by feeding crocodiles looks much like stone-tool incisions and pits, with a few distinctive twists such as deep scratches. Njau retrieved and studied cow and goat bones from carcasses that had been eaten by crocodiles housed at two animal farms in Tanzania.

In the new study, the scientists used Njau’s findings to reassess marks on fossils previously excavated in Ethiopia and dating to around 4.2 million, 3.4 million and 2.5 million years ago. Damage to these fossils has generally been attributed to butchery with stone tools.

Incisions and pits on arm bones from an ancient hominid, Australopithecus anamensis, and similar marks on a horse’s leg bone likely resulted from crocodile bites and not stone-tool use, as initially suspected, the investigators say. If stone tools had indeed damaged the A. anamensis remains, that would raise the possibility of cannibalism — a difficult behavior to confirm with fossils. Tellingly, Sahle’s team argues, these bones come from what were once waterside areas. Some were found in the same sediment layer as crocodile remains. Marks on these bones include deep scratches consistent with crocodile bites.

The horse fossil comes from a spot along an ancient lakeshore where no stone tools have been found, a further clue in favor of damage from croc bites.

Jagged pits, incisions and other marks scar a leg fragment and lower jaw from an ancient hoofed animal. But microscopic analyses could not definitively attribute the damage to stone tools or crocodile bites.

In light of these findings, the ancient California and 3.4-million-year-old East Africa bones should also be reexamined with the possibility of croc damage in mind, White says. For now, the earliest confirmed stone-tool marks occur on animal bones from two East African sites dating to around 2.5 million years ago (SN: 4/17/04, p. 254), he adds.

The range of crocodile marks described in the new study doesn’t look “especially like” damage to the 130,000-year-old mastodon bones on California’s coast, says paleontologist Daniel Fisher of the University of Michigan in Ann Arbor, a coauthor of the ancient California bones paper. No fossil evidence indicates crocodiles lived there at that time, he adds. Several lines of evidence, including pounding marks and damage near joints, point to stone-tool use at the West Coast site, says archaeologist Richard Fullagar of the University of Wollongong in Australia, also a coauthor of the mastodon paper.

Further studies of the 3.4-million-year-old African bones previously reported as probable examples of animal butchery will statistically compare the probability of various causes for particular marks, including crocodile bites, says Shannon McPherron, the lead author of the earlier study and an archaeologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. In that way, researchers can assess whether any one cause stands out as the strongest candidate.

‘Mammals nocturnal until dinosaur extinction’


This 2016 video says about itself:

Top 7 Prehistoric Mesozoic Mammals

Mesozoic Mammals. The first mammals on Earth. They lived among the giant dinosaurs (Mesozoic) but prevailed and evolved to control the planet and are our ancestors! Juramaia, the Jurassic mother, Repenomamus, the mammal that ate dinosaurs and much more!

From University College London in England:

Mammals switched to daytime activity after dinosaur extinction

November 6, 2017

Mammals only started being active in the daytime after non-avian dinosaurs were wiped out about 66 million years ago (mya), finds a new study led by UCL and Tel Aviv University‘s Steinhardt Museum of Natural History.

A long-standing theory holds that the common ancestor to all mammals was nocturnal, but the new discovery reveals when mammals started living in the daytime for the first time. It also provides insight into which species changed behaviour first.

The study, published today in Nature Ecology & Evolution, analysed data of 2415 species of mammals alive today using computer algorithms to reconstruct the likely activity patterns of their ancient ancestors who lived millions of years ago.

Two different mammalian family trees portraying alternative timelines for the evolution of mammals were used in the analysis. The results from both show that mammals switched to daytime activity shortly after the dinosaurs had disappeared. This change did not happen in an instant — it involved an intermediate stage of mixed day and night activity over millions of years, which coincided with the events that decimated the dinosaurs.

“We were very surprised to find such close correlation between the disappearance of dinosaurs and the beginning of daytime activity in mammals, but we found the same result unanimously using several alternative analyses,” explained lead author, PhD student Roi Maor (Tel Aviv University and UCL).

The team found that the ancestors of simian primates — such as gorillas, gibbons and tamarins — were among the first to give up nocturnal activity altogether. However, the two evolutionary timelines varied, giving a window between 52-33 mya for this to have occurred.

This discovery fits well with the fact that simian primates are the only mammals that have evolved adaptations to seeing well in daylight. The visual acuity and colour perception of simians is comparable to those of diurnal reptiles and birds — groups that never left the daytime niche.

“It’s very difficult to relate behaviour changes in mammals that lived so long ago to ecological conditions at the time, so we can’t say that the dinosaurs dying out caused mammals to start being active in the daytime. However, we see a clear correlation in our findings,” added co-author Professor Kate Jones (UCL Genetics, Evolution & Environment).

“We analysed a lot of data on the behaviour and ancestry of living animals for two reasons — firstly, because the fossil record from that era is very limited and secondly, behaviour as a trait is very hard to infer from fossils,” explained co-author, Professor Tamar Dayan (Chair of The Steinhardt Museum of Natural History, Tel Aviv University).

“You have to observe a living mammal to see if it is active at night or in the day. Fossil evidence from mammals often suggest that they were nocturnal even if they were not. Many subsequent adaptations that allow us to live in daylight are in our soft tissues.”

The team say further research is needed to better populate the mammalian family tree to give more accurate information on when the behaviour of species changes from night time to day time activity.

Green turtles, new research


This video is called Scuba Dive Hawaii – Hawaiian Green Sea Turtle Eats a Sponge.

From the University of Exeter in England:

Crime-scene technique used to track turtles

November 6, 2017

Scientists have used satellite tracking and a crime-scene technique to discover an important feeding ground for green turtles in the Mediterranean.

University of Exeter researchers measured “stable isotope ratios” — a chemical signature also used by forensic scientists — to discover which foraging grounds turtles had come from to breed in Cyprus.

They discovered that Lake Bardawil, on Egypt’s north coast, is now the most important foraging ground for turtles which breed at Alagadi in Cyprus.

The researchers believe few breeding females came from the Lake Bardawil feeding ground until 2010. It is likely that changes to the ecosystem have made this shallow saline lake a top foraging site.

“Our satellite tracking of turtles breeding in Cyprus has been going on for some years,” said senior author Professor Brendan Godley, director of the Centre for Ecology and Conservation on the University of Exeter’s Penryn Campus in Cornwall.

“This meant we knew where many of the turtles went to forage for food, but our preliminary analysis using stable isotope ratios showed a major foraging area had been missed.

“A large proportion of turtles had isotope ratios that did not correspond to sites previously identified, and we tracked five of them. Five out of five went to Lake Bardawil.”

Green turtles swim hundreds of miles between feeding and breeding areas, and the research suggests 82 per of females show “extremely high” consistency in isotope ratios — meaning they keep going back to the same places.

In terms of stable isotope ratios, animals “are what they eat,” meaning tests can reveal where they have spent time.

“This research demonstrates how stable isotope analysis can help us learn more about the lives of species like green turtles,” said first author Dr Phil Bradshaw, also from the University of Exeter.

“Using a combination of this analysis and satellite tracking gives us more reliable data, and this can be used to measure the success of future conservation efforts.”

Feeding the animals is altering the behaviour and eating habits of the green turtle in the Canary Islands (Spain). This is the conclusion of a study published in the journal Science of the Total Environment, carried out by a team in which Lluís Cardona, from the Faculty of Biology and the Biodiversity Research Institute of the University of Barcelona (IRBio) takes part. The study, with Catalina Monzón (University of Las Palmas de Gran Canaria) as first author, is also signed by experts from ASD Biodiversidad, Oceanografic Foundation, and La Tahonilla and Tafira Wildlife Rescue Centers, in the Canary Islands: here.

Dinosaur family tree not yet clear


Dinosaur family tree theories. Credit: Max Langer

From the University of Bristol in England:

Time to rewrite the dinosaur textbooks? Not quite yet!

November 1, 2017

The classification of the dinosaurs might seem to be too obscure to excite anyone but the specialists.

However, this is not at all the case. Recently, Matthew Baron and colleagues from the University of Cambridge proposed a radical revision to our understanding of the major branches of dinosaurs, but in a critique published today some caution is proposed before we rewrite the textbooks.

Every child learns that dinosaurs fall into two major groups, the Ornithischia (bird-hipped dinosaurs; Stegosaurus, Triceratops, Iguanodon and their kin) and the Saurischia (lizard-hipped dinosaurs; the predatory theropods, such as Tyrannosaurus, and the long-necked sauropodomorphs, including such well-known forms as Diplodocus).

Baron and colleagues proposed a very different split, pairing the Ornithischia with the Theropoda, terming the new group the Ornithoscelida, and leaving the Sauropodomorpha on its own.

This video says about itself:

The New Dinosaur Family Tree Explained

29 March 2017

You may have heard that dinosaur classification has been changed recently, and in this video I’ll explain what has happened and how this affects our views of dinosaurs overall.

The University of Bristol article continues:

Their evidence seemed overwhelming, since they identified at least 18 unique characters shared by ornithischians and theropods, and used these as evidence that the two groups had shared a common ancestor.

An international consortium of specialists in early dinosaurs, led by Max Langer from the Universidade de São Paulo, Brazil, and including experts from Argentina, Brazil, Germany, Great Britain, and Spain has now re-evaluated the data provided by Baron et al. in support of their claim.

Their results, presented today in the journal Nature, show that it might still be too early to re-write the textbooks for dinosaurs.

In this new evaluation, the authors found support for the traditional model of an Ornithischia-Saurischia split of Dinosauria, but also noted that this support was very weak, and the alternative idea of Ornithoscelida is only slightly less likely.

Max Langer said: “This took a great deal of work by our consortium, checking many dinosaurs on all continents first-hand to make sure we coded their characters correctly.

“We thought at the start we might only cast some doubt on the idea of Ornithoscelida, but I’d say the whole question now has to be looked at again very carefully.”

Baron and colleagues believed their data suggested that dinosaurs might have originated in the northern hemisphere, but the re-analysis confirms the long-held view that the most likely site of origin is the southern hemisphere, and probably South America.

Professor Mike Benton from the University of Bristol’s School of Earth Sciences, a member of the revising consortium, added: “In science, if you wish to overthrow the standard viewpoint, you need strong evidence.

“We found the evidence to be pretty balanced in favour of two possible arrangements at the base of the dinosaurian tree. Baron and colleagues might be correct, but we would argue that we should stick to the orthodox Saurischia-Ornithischia split for the moment until more convincing evidence emerges.”

Steve Brusatte of the University of Edinburgh, a member of the consortium, said: “Up until this year, we thought we had the dinosaur family tree figured out.

“But right now, we just can’t be certain how the three major groups of dinosaurs are related to each other. In one sense it’s frustrating, but in another, it’s exciting because it means that we need to keep finding new fossils to solve this mystery.”