Big hammerhead shark in Bahamas, video


This 28 September 2018 video says about itself:

MASSIVE Hammerhead Shark Filmed in Bahamas

On this episode of Blue Wilderness, Mark and crew set off for world-famous Tiger Beach in hopes with coming face to face with some very LARGE sharks….and just when they thought their adventure was coming to an end, Mark spots one MASSIVE Hammerhead Shark in the waters just off the coast of the Bahamas! It’s so HUGE that you’ll have to see it to believe it!

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‘Extinct’ Bahama nuthatch just survived hurricane


This 22 August 2018 video says about itself:

Endangered Bahama Nuthatch spotted | University of East Anglia (UEA)

One of the rarest birds in the western hemisphere has been spotted by researchers from the University of East Anglia. The Bahama Nuthatch is an endangered species, found only in the native pine forests on Grand Bahama Island, approximately 150km off Palm Beach, Florida.

The research team fear that it could be one of the last birds in existence – placing the species on the verge of extinction and certainly among the world’s most critically endangered birds.

From the University of East Anglia in England:

Bird feared extinct rediscovered in the Bahamas

August 23, 2018

One of the rarest birds in the western hemisphere, the Bahama Nuthatch, has been rediscovered by research teams searching the island of Grand Bahama.

The finding is particularly significant because the species had been feared extinct following the catastrophic damage caused by Hurricane Matthew in 2016, and had not been found in subsequent searches.

But it is feared that there could only be two left — placing the species on the verge of extinction and certainly among the world’s most critically endangered birds.

The Bahama Nuthatch is an endangered species, only known from a small area of native pine forest on Grand Bahama Island, which lies approximately 100 miles off Palm Beach, Florida.

University of East Anglia masters students Matthew Gardner and David Pereira set out on a three-month expedition to find this and other endemic Caribbean pine forest bird species.

They made their way through dense forest with thick ‘poisonwood’ understorey — the layer of vegetation growing beneath the main forest canopy — in what is thought to be one of the most exhaustive searches of the island.

They worked in partnership with Nigel Collar and David Wege from Birdlife International and the Bahamas National Trust, the organisation which works to protect the habitats and species of the Bahama Islands.

Meanwhile a second team of Bahamian students, led by Zeko McKenzie of the University of The Bahamas-North and supported by the American Bird Conservancy, also searched for the bird.

The Bahama Nuthatch has a long bill, a distinctive high-pitched squeaky call, and nests only in mature pine trees. There had been a sharp decline in its population crashing from an estimated 1,800 in 2004 to just 23 being seen in a survey in 2007. The decline likely began in the 1950s due to habitat loss due to timber removal, and more recently due to hurricane damage, storm surges having killed large areas of native forest.

Both teams made Nuthatch sightings in May, and the UEA team were lucky enough to capture the elusive bird on film.

Dr Diana Bell, from UEA’s School of Biological Sciences, said: “The Bahama Nuthatch is a critically endangered species, threatened by habitat destruction and degradation, invasive species, tourist developments, fires and hurricane damage.

“Our researchers looked for the bird across 464 survey points in 34,000 hectares of pine forest. It must have been like looking for a needle in a hay stack. They played out a recording of the bird’s distinctive call in order to attract it.

“As well as searching for the elusive bird, they also collected environmental data to better understand its habitat preferences and surveyed the extent of hurricane and fire damage”, she added.”

Matthew Gardner said: “We were the first to undertake such an exhaustive search through 700km of forest on foot.

“We had been scouring the forest for about six weeks, and had almost lost hope. At that point we’d walked about 400km. Then, I suddenly heard its distinctive call and saw the unmistakable shape of a Nuthatch descending towards me. I shouted with joy, I was ecstatic!”

The UEA team made six Nuthatch sightings in total, and McKenzie’s team independently made five sightings, using different methods, in the same small area of forest — including a sighting of what they believe to be two birds together.

Mr Gardner said: “During three months of intensive searching we made six Bahama Nuthatch sightings. Our search was extremely thorough but we never saw two birds together, so we had thought there might only be one left in existence.”

“The other team have reported seeing two together so that is promising. However, these findings place the species on the verge of extinction and certainly amongst the world’s most critically endangered birds.”

“We also don’t know the sex of the birds. In many cases when birds dwindle to such small numbers, any remaining birds are usually male.”

“The photographs clearly show this distinctive species and cannot be anything else” said Michael Parr, President of American Bird Conservancy and a UEA alumnus.

“Fortunately this is not a hard bird to identify, but it was certainly a hard bird to find”, he added.

The Nuthatch was spotted in a small area known as Lucaya Estates. During the research project, birds were seen and heard in three distinct but nearby locations within this area.

Researcher Zeko McKenzie said: “Although the Bahama Nuthatch has declined precipitously, we are encouraged by the engagement of conservation scientists who are now looking for ways to save and recover the species.”

The UEA team however are less optimistic as the exact drivers of the precipitous decline of the bird are still unclear.

Dr Diana Bell said: “Sadly, we think that the chances of bringing this bird back from the brink of extinction are very slim — due to the very low numbers left, and because we are not sure of the precise drivers for its decline.

“But it is still absolutely crucial that conservation efforts in the native Caribbean pine forest do not lapse as it is such an important habitat for other endemic birds including the Bahama Swallow, Bahama Warbler and Bahama Yellowthroat.

“The habitat is also incredibly important for North American migrants including the Kirtlands Warbler“, she added.

Ellsworth Weir, Grand Bahama Parks Manager at the Bahamas National Trust, said: “It has been a pleasure for The Bahamas National Trust to host both Matthew and David as they conducted this very important research on Grand Bahama.”

“Their work has taken them across the length and breadth of the island in what was likely the most in depth search to be conducted. Their research, which was inclusive of bird and habitat surveys, has helped to answer questions that some residents have been asking for some time.”

“Sadly, we realize now that we are faced with a very dire situation regarding the Bahama Nuthatch. We wouldn’t have realized the extent of the issue without the persistent efforts of David and Matthew.”

See also here.

Blue hole diving in the Bahamas


This video says about itself:

15 December 2017

Jonathan travels to Andros, an island in the Bahamas, to investigate underwater caves that start in blue holes. A blue hole looks like a pond, but leads into a vast underwater cave system. In the Bahamas, these caves often lead to the ocean. As Jonathan explores the ocean end of the caves, he learns how the two systems are connected.

JONATHAN BIRD‘S BLUE WORLD is an Emmy Award-winning underwater science/adventure program.

Abaco, Bahamas lost songbirds by climate change


This video from the USA says about itself:

Eastern Bluebird Song

23 April 2015

Male Bluebird on the Ball listening to other birds call, sing, and a woodpecker pounding, chased by doves, sliding off the ball and finally singing as a female sits in her new front yard nest nearby.

From the University of California – Riverside in the USA:

Bahamian songbirds disappeared during last glacial-interglacial transition

Warming event 12,000 years highlights the impact of climate change on ecosystems

August 29, 2017

Two species of songbirds that once made a home in the Bahamas likely became extinct on the islands because of rising sea levels and a warmer, wetter climate, according to a new study by researchers at the University of California, Riverside and the University of Florida, Gainesville. The study, which was published in the Proceedings of the National Academy of Sciences, presents a historical view of how climate change and the resulting habitat loss can affect Earth’s biodiversity.

Titled “Origin, Paleoecology and Extirpation of Bluebirds and Crossbills in the Bahamas Across the Last Glacial-Interglacial Transition,” the authors are Janet Franklin, distinguished professor of biogeography in UCR’s College of Natural and Agricultural Sciences, and David Steadman, curator of ornithology at the Florida Museum of Natural History at the University of Florida.

The Eastern Bluebird (Sialia sialis) and Hispaniolan Crossbill (Loxia megaplaga) were among 17 species of birds that were found on the Bahamian Island of Abaco during the last Ice Age, but that no longer live there today. Both species are still alive elsewhere, with the former found in continental North America and the latter in Hispaniola. Fossil records from Abaco suggest that these birds resided on the island year-round, as opposed to migrating there in winter.

This is a Hispaniolan Crossbill video in Spanish from the Dominican Republic.

“The abundance of fossils, the presence of young birds among the fossils, and the evolution of a shorter wingspan in the Eastern Bluebird all suggest that these birds did not migrate to the island but were a resident population. But then they disappeared,” Franklin said.

Unlike many bird species that are now extinct on the Earth’s small islands, the Eastern Bluebird and the Hispaniolan Crossbill disappeared long before the first people arrived, uncoupling their extinction from human actions, such as the introduction of new predators and habitat loss for agricultural use. Instead, the fossil record indicates they vanished during the Earth’s glacial-interglacial transition, which occurred about 12,000 years ago and led to much warmer conditions and the start of the current Holocene period.

Using topographic data and sea level models, Franklin modelled the effect of this transition, showing how of a 400-foot rise in sea level affected the Bahamas, reducing their land area by more than ten-fold. Climate models showed that the cooler, drier Bahamian weather would have provided suitable habitat for these species.

“We know from studying these birds today that their habitats are pine grasslands that are found in cooler, dryer regions. These habitats were lost when the Bahamian Islands became more tropical,” Franklin said.

Franklin said the research underscores what might happen to threatened species in the future, with rapid climate change happening on a scale of decades rather than millennia.

“In the coming decades both modern day climate change and other human activities will have a profound impact on our ecosystem. Anthropogenic climate change and resulting sea level rise are now happening much more rapidly than at the transition from the last ice age to the modern global climate. Species and ecosystems do not have time to adjust, especially when climate change is happening in a world where people have transformed the face of the planet in other ways, through deforestation and so forth.”

Bahamas pupfish, new study


Bahamas pupfish

This picture about Bahamas pupfish shows San Salvador Island generalists (red), molluscivores (green), large-jawed scale-eaters (dark blue), small-jawed scale-eaters (light blue), and outgroup species (black) in the Caribbean, California, and Mexico. Credit: Emilie Richards and Christopher Martin; CC-BY.

From PLOS:

San Salvador pupfish acquired genetic variation from island fish to eat new foods

Study finds that ecological and genetic factors both contributed to rise of new pupfish species

August 10, 2017

Pupfish living in salty lakes on San Salvador Island were able to diversify into multiple species with different eating habits, in part, by interbreeding with pupfish from other islands in the Caribbean, report Emilie Richards and Christopher Martin, of the University of North Carolina at Chapel Hill, August 10, 2017 in PLOS Genetics.

Pupfish are small, brightly colored fish that commonly live in coastal areas and salty lakes and feed off of algae. But on San Salvador Island in the Bahamas, a group of pupfish has undergone adaptive radiation, a process where existing species rapidly evolve and differentiate into new species, to take advantage of a new environment. Where most pupfish species eat algae, one San Salvador species has a protruding nasal region that allows it to eat snails, while another has enlarged jaws that enable it to bite the scales off of other fish. To understand why these specialized species evolved only on San Salvador Island, despite the availability of scales and snails across the Caribbean, the researchers used whole genomes to identify regions of the San Salvador pupfish genome that came from outside sources.

They examined 42 pupfish genomes collected from populations on San Salvador Island, two distant Caribbean islands, Laguna Chichancanab in Mexico, and Devil’s Hole in California, to identify regions of the genome that have been exchanged between San Salvador Island and outside pupfish populations. They identified 11 gene variants in the San Salvador fish that came from other Caribbean pupfish populations, with four of these regions known to affect jaw size and shape, traits important in the evolution of their specialized diets.

The study suggests that multiple outside sources of genetic variation contributed to the adaptations found in pupfishes on San Salvador Island. These findings indicate that a complex suite of factors, including breeding with related species, in addition to new ecological opportunities, may be necessary for adaptive radiations to occur.

“The really intriguing thing here is that new species are assembled from different pots of genetic variation over a very large range. Our own species is likely no different,” says study corresponding author Dr. Martin.

Bahamas wild spotted dolphins


This video says about itself:

27 January 2017

In the Bahamas, a group of wild Spotted Dolphins play “keep away” with a bandana–a game they invented with seaweed and people started playing with them. Jonathan travels to the Bahamas with dolphin expert Wayne Scott Smith to meet these playful animals and try playing the Bandana Game with them.

How a dolphin eats an octopus without dying, by Sarah Zielinski. 1:00pm, April 25, 2017: here.