Prehistoric Pacific marine mammals discoveries


This video is called Whales evolution.

Not only news about big land mammals during the Ice Age … also about big marine mammals before the Ice Age.

From the University of Otago in New Zealand:

Strange marine mammals of ancient North Pacific revealed

February 5, 2014

Summary:

The pre-Ice Age marine mammal community of the North Pacific formed a strangely eclectic scene, new research reveals. Studying hundreds of fossil bones and teeth excavated from the San Francisco Bay Area‘s Purisima Formation, scientists have put together a record of 21 marine mammal species including dwarf baleen whales, odd double-tusked walruses, porpoises with severe underbites and a dolphin closely related to the now-extinct Chinese river dolphin.

The pre-Ice Age marine mammal community of the North Pacific formed a strangely eclectic scene, research by a Geology PhD student at New Zealand’s University of Otago reveals.

Studying hundreds of fossil bones and teeth he excavated from the San Francisco Bay Area’s Purisima Formation, Robert Boessenecker has put together a record of 21 marine mammal species including dwarf baleen whales, odd double-tusked walruses, porpoises with severe underbites and a dolphin closely related to the now-extinct Chinese river dolphin.

Among his finds, which were fossilized 5 to 2.5 million years ago, is a new species of fossil whale, dubbed Balaenoptera bertae, a close relative of minke, fin, and blue whales.

Mr Boessenecker named the whale in honour of San Diego State University‘s Professor Annalisa Berta, who has made numerous contributions to the study of fossil marine mammals and mentored many students.

Although an extinct species, it belongs within the same genus as minke and fin whales, indicating that the Balaenoptera lineage has lasted for 3-4 million years. Balaenoptera bertae would have been approximately 5-6 meters in length, slightly smaller than modern minke whales, Mr Boessenecker says.

His findings appear in the most recent edition of the international journal Geodiversitas.

The publication represents eight years of research by Mr Boessenecker, who was 18 in 2004 when he was tipped off by a local surfer about bones near Half Moon Bay. When he discovered the fossil site, he was astonished by the numerous bone-beds and hundreds of bones sticking out of the cliffs.

He excavated the incomplete skull of Balaenoptera bertae during early field research there in 2005 and it was encased in a hard concretion that took five years to remove.

“The mix of marine mammals I ended up uncovering was almost completely different to that found in the North Pacific today, and to anywhere else at that time,” he says.

Primitive porpoises and baleen whales were living side-by-side with comparatively modern marine mammals such as the Northern fur seal and right whales. And species far geographically and climatically removed from their modern relatives also featured, such as beluga-like whales and tusked walruses, which today live in the Arctic, he says.

“At the same time as this eclectic mix of ancient and modern-type marine mammals was living together, the marine mammal fauna in the North Atlantic and Southern Ocean were already in the forms we find today.”

Mr Boessenecker says this strange fauna existed up until as recently as one or two million years ago. Its weirdness was likely maintained by warm equatorial waters and barriers to migration by other marine mammals posed by the newly formed Isthmus of Panama, and the still-closed Bering Strait.

“Once the Bering Strait opened and the equatorial Pacific cooled during the Ice Age, modernised marine mammals were able to migrate from other ocean basins into the North Pacific, leading to the mix we see today,” he says.

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Pacific humpback whales, new discoveries


This video is called Humpback Whales – BBC documentary excerpt.

From LiveScience:

Distinct Humpback Whale Populations Found in North Pacific

By Laura Poppick, Staff Writer

December 04, 2013 03:02pm ET

Five distinct humpback whale populations have been identified across the North Pacific Ocean in the most comprehensive genetic study of the mammals in this region yet, a new study reports.

The ranges of the newly identified populations include: Hawaii; Mexico; Central America; Okinawa and the Philippines; and an additional West Pacific population whose range has yet to be determined more specifically.

Humpback whales are found in all oceans of the world, but the North Pacific humpbacks are genetically isolated enough to be considered a subspecies of other humpbacks, of which the new populations are further subclassifications, study co-author Scott Baker, a professor of fisheries and wildlife at Oregon State University, said in a statement.

“Even within these five populations, there are nuances,” Baker said. “The Mexico population, for example, has ‘discrete’ sub-populations off the mainland and near the Revillagigedo Islands, but because their genetic differentiation is not that strong, these are not considered ‘distinct’ populations.”

To distinguish the separate populations, the team studied DNA within 2,200 tissue samples of whales from 10 feeding regions and eight winter breeding regions during a three-year study called SPLASH, which stands for Structure of Populations, Levels of Abundance and Status of Humpbacks.

The team studied distinct breeding and feeding grounds because these are the types of “barriers” that isolate marine animal populations and make them become genetically distinct, whereas terrestrial animals more commonly become isolated and genetically distinct by geographic barriers, Baker said. Researchers think that migration routes, feeding and breeding grounds of individuals are passed from mother to calf and through subsequent generations, with the separations between populations ultimately becoming evident in their DNA as a distinct marker of the population.

Using photo identification records to estimate humpback whale populations, the researchers suggest roughly 22,000 humpbacks currently swim throughout the North Pacific, which is close to the population size of humpbacks before whaling decimated their populations during the 19th and 20th centuries. Commercial whaling has been banned by the International Whaling Commission since 1966, when hunting had dwindled the species down to roughly 5,000 individuals worldwide.

Though the U.S. Endangered Species Act still lists humpbacks as endangered, the International Union for the Conservation of Nature currently only recognizes two populations as endangered — one in the Sea of Arabia and one in Oceania. The team believes that one or more of the newly identified populations may qualify as endangered as well.

“Each of the five distinct populations has its own history of exploitation and recovery that would need to be part of an assessment of its status,” Baker said.

The study findings are detailed this week in the journal Marine Ecology – Progress Series.

Killer whales, new research


This video is called BBC Natural World: The Woman Who Swims With Killer Whales.

From Wildlife Extra:

Killer whales found to eavesdrop on prey

December 2013: UK Scientists have found evidence that marine-mammal-eating killer whales rely on acoustic clues to locate their prey.

While biologists had evidence that the whales do not echolocate while hunting, due to the excellent hearing of the seals, porpoises and other animals the whales hunt, they were still unsure exactly how the animals do find their prey in the murky northern waters off the west coast of North America.

However, a two-year study by Volker Deecke, a researcher at the Centre for Wildlife Conservation at the University of Cumbria, UK has revealed that killer whales can successfully locate prey even in near-complete darkness. Deecke notes that this new evidence of night-time hunting rules out visual cues as the only means of prey detection.

“We now suspect that mammal-eating killer whales are primarily eavesdropping on sounds generated by their prey to find food,” he said.

Deecke and his colleagues traveled to Alaska to conduct the study, analysing huge quantities of data gathered from acoustic recording tags placed on 13 killer whales. The tags, which are about the size of a cell phone, were attached to the whales with four suction cups and could stay on for up to 16 hours.

The tags’ accelerometers, compass, depth sensor, and hydrophone recorded data on the animals’ movements and any sounds it heard or made. Deecke and his colleagues were able to identify predation events by the characteristic sound of a whale dispatching its prey with a hit from its tail fluke.

Deecke said of one unfortunate seal’s demise: “As soon as we put one of the tags on, it started to record seal roars, which are part of the display that male harbor seals use to attract females. Over the next half hour the roars got louder and louder, then there are a sequence of three quite loud roars that suggest the seal is within a few hundred meters of the killer whale. Twenty-seven seconds later there are the sounds of a predation event, and then no more roars.”

Deecke notes that such a story is compelling but does not provide direct evidence that killer whales are tuning in to the sounds of their prey. Going forward, he hopes to use playback experiments to test killer whales’ responses to recorded seal roars and porpoise echolocation clicks.

Save Suwarrow islands’ seabirds


This video is called BirdLife Invasive Species Programme – Saving Suwarrow’s Seabirds.

BirdLife writes about this:

BirdLife launches invasive species video – Saving Suwarrow’s Seabirds

Tue, Jul 16, 2013

At BirdLife’s World Congress last month we launched our newest global conservation programme. The BirdLife Invasive Alien Species Programme will work around the globe to tackle one of the greatest of threats to our natural world. Today we’re launching a new video by award-winning filmmaker Nick Hayward showcasing just what it takes to eliminate rats in restoring a remote atoll in the South Pacific…

Invasive alien species are animals and plants that have been introduced into a natural environment where they are not normally found. In the last 500 years, species like rats and cats have driven over 70 bird species to extinction.

“To tackle this major threat to birds and nature we recently launched the BirdLife Invasive Alien Species Programme”, said Donald Stewart – BirdLife Pacific Director.

From local to global, the new programme will develop and share our expertise to tackle invasive alien species whilst also calling for more effective policies and support for their delivery.

“Experience has shown benefits to birds, biodiversity and local economies are substantial where invasive threats are managed”, noted Don.

“Across sites of importance for endangered native wildlife the BirdLife Partnership will intensify this effort through the eradication or control of exotic species, and implementation of locally-led biosecurity measures to ensure these threats don’t return”.

On the ground, BirdLife Pacific, and the BirdLife Partner in the Cook Islands Te Ipukarea Society, recently completed an expedition to eradicate rats from Suwarrow Atoll.

“Suwarrow is one of increasingly few sites where seabirds occur largely undisturbed”, said Steve Cranwell – BirdLife Pacific Seabird Manager.

“The significance of which is reflected in the proportions of birds present including nine percent of the world’s population of Lesser Frigatebird, three percent of the world’s Red-Tailed Tropicbird and in excess of a hundred thousand Sooty Tern”.

Sadly, the growing rat population and their spread across the Atoll, threatened the breeding seabirds.

In order to conserve this globally important seabird site, BirdLife International and Te Ipukarea Society recently spent a month on the atoll in a carefully planned bid to remove the rats.

Joining the team was wildlife documentary filmmaker Nick Hayward – with the support of Wildiaries – seeking to produce a film about the operation. Nick won a place on the trip following a worldwide search by BirdLife for an experienced wildlife filmmaker, and posted regular blog updates from the field via satellite phone.

Nick’s now finished his video that provides a brief insight into what it takes to complete such an operation. Many months in the planning the team travelled the 930 km from Rarotonga to Suwarrow by sea. Twice. And dealt with challenges associated with unpredictable weather, swarms of wasps, and abundant coconut crab in a bid to banish invasive rats from Suwarrow.

It will be some time until we know for sure if their efforts have been successful, but early signs look positive.

Ice Age ocean life and iron


This video says about itself:

NASA | Earth Science Week: The Ocean’s Green Machines

“The Ocean’s Green Machines” is Episode 3 in the six-part series “Tides of Change”, exploring amazing NASA ocean science to celebrate Earth Science Week 2009.

One tiny marine plant makes life on Earth possible: phytoplankton. These microscopic photosynthetic drifters form the basis of the marine food web, they regulate carbon in the atmosphere, and are responsible for half of the photosynthesis that takes place on this planet. Earth’s climate is changing at an unprecedented rate, and as our home planet warms, so does the ocean. Warming waters have big consequences for phytoplankton and for the planet.

From Woods Hole Oceanographic Institution in the USA:

Scientists solve a 14,000-year-old ocean mystery

At the end of the last Ice Age, as the world began to warm, a swath of the North Pacific Ocean came to life. During a brief pulse of biological productivity 14,000 years ago, this stretch of the sea teemed with phytoplankton, amoeba-like foraminifera and other tiny creatures, who thrived in large numbers until the productivity ended—as mysteriously as it began—just a few hundred years later.

Researchers have hypothesized that iron sparked this surge of ocean life, but a new study led by Woods Hole Oceanographic Institution (WHOI) scientists and colleagues at the University of Bristol (UK), the University of Bergen (Norway), Williams College and the Lamont Doherty Earth Observatory of Columbia University suggests iron may not have played an important role after all, at least in some settings. The study, published in the journal Nature Geoscience, determines that a different mechanism—a transient “perfect storm” of nutrients and light—spurred life in the post-Ice Age Pacific. Its findings resolve conflicting ideas about the relationship between iron and biological productivity during this time period in the North Pacific—with potential implications for geo-engineering efforts to curb climate change by seeding the ocean with iron.

“A lot of people have put a lot of faith into iron—and, in fact, as a modern ocean chemist, I’ve built my career on the importance of iron—but it may not always have been as important as we think,” says WHOI Associate Scientist Phoebe Lam, a co-author of the study.

Because iron is known to cause blooms of biological activity in today’s North Pacific Ocean, researchers have assumed it played a key role in the past as well. They have hypothesized that as Ice Age glaciers began to melt and sea levels rose, they submerged the surrounding continental shelf, washing iron into the rising sea and setting off a burst of life.

Past studies using sediment cores—long cylinders drilled into the ocean floor that offer scientists a look back through time at what has accumulated there—have repeatedly found evidence of this burst, in the form of a layer of increased opal and calcium carbonate, the materials that made up phytoplankton and foraminifera shells. But no one had searched the fossil record specifically for signs that iron from the continental shelf played a part in the bloom.

Lam and an international team of colleagues revisited the sediment core data to directly test this hypothesis. They sampled GGC-37, a core taken from a site near Russia’s Kamchatka Peninsula, about every 5 centimeters, moving back through time to before the biological bloom began. Then they analyzed the chemical composition of their samples, measuring the relative abundance of the isotopes of the elements neodymium and strontium in the sample, which indicates which variant of iron was present. The isotope abundance ratios were a particularly important clue, because they could reveal where the iron came from—one variant pointed to iron from the ancient Loess Plateau of northern China, a frequent source of iron-rich dust in the northwest Pacific, while another suggested the younger, more volcanic continental shelf was the iron source.

What the researchers found surprised them.

“We saw the flux of iron was really high during glacial times, and that it dropped during deglaciation,” Lam says. “We didn’t see any evidence of a pulse of iron right before this productivity peak.”

The iron the researchers did find during glacial times appeared to be supplemented by a third source, possibly in the Bering Sea area, but it didn’t have a significant effect on the productivity peak. Instead, the data suggest that iron levels were declining when the peak began.

Based on the sediment record, the researchers propose a different cause for the peak: a chain of events that created ideal conditions for sea life to briefly flourish. The changing climate triggered deep mixing in the North Pacific ocean, which stirred nutrients that the tiny plankton depend on up into the sea’s surface layers, but in doing so also mixed the plankton into deep, dark waters, where light for photosynthesis was too scarce for them to thrive. Then a pulse of freshwater from melting glaciers—evidenced by a change in the amount of a certain oxygen isotope in the foraminifera shells found in the core—stopped the mixing, trapping the phytoplankton and other small creatures in a thin, bright, nutrient-rich top layer of ocean. With greater exposure to light and nutrients, and iron levels that were still relatively high, the creatures flourished.

“We think that ultimately this is what caused the productivity peak—that all these things happened all at once,” Lam says. “And it was a transient thing, because the iron continued to drop and eventually the nutrients ran out.”

The study’s findings disprove that iron caused this ancient bloom, but they also raise questions about a very modern idea. Some scientists have proposed seeding the world’s oceans with iron to trigger phytoplankton blooms that could trap some of the atmosphere’s carbon dioxide and help stall climate change. This idea, sometimes referred to as the “Iron Hypothesis,” has met with considerable controversy, but scientific evidence of its potential effectiveness to sequester carbon and its impact on ocean life has been mixed.

“This study shows how there are multiple controls on ocean phytoplankton blooms, not just iron,” says Ken Buesseler, a WHOI marine chemist who led a workshop in 2007 to discuss modern iron fertilization. “Certainly before we think about adding iron to the ocean to sequester carbon as a geoengineering tool, we should encourage studies like this of natural systems where the conditions of adding iron, or not, on longer and larger time scales have already been done for us and we can study the consequences.”

New octopus species discovery, video


This video from the USA says about itself:

Larger Pacific Striped Octopus

March 7, 2013

Academy biologist Richard Ross, who studies octopuses and their relatives, has spent the last 13 months raising and studying the behavior of this recently rediscovered species, along with Dr. Roy Caldwell of the University of California, Berkeley. While they are still working on a formal description of the species, which doesn’t yet have a scientific name, they didn’t want to wait any longer to share this spectacular animal with the public. Visit our Animal Attraction Exhibit to see her.

Fiji birds, new report


This video is called Birds of Fiji.

From BirdLife:

State of Fiji’s birds report launched

Fri, May 31, 2013

Fiji’s first ever State of Birds report ‘Fiji: State of Birds 2013’ has been launched by NatureFiji-MareqetiViti with the assistance of BirdLife International, the Department of the Environment and local ornithologists.

Birds are by far Fiji’s most conspicuous form of terrestrial wildlife – they are inspirational, they sing, they are fairly easy to observe and identify, and there is a limited number of species.

Biodiversity conservation in Fiji requires the support of landowners and the populace, who can better understand, participate in and support conservation if they are familiar with and knowledgeable about the species of concern.

The new report provides an overview of the issues and critical considerations facing Fiji’s birds and emphasises how useful birds are as flagships for other elements of our biodiversity. Birds have long been used as indicators of the state of the world’s ecosystems, providing insights into habitat loss, deterioration, pollution and, increasingly, for climate change.

All of Fiji’s birds are special but some are particularly important. These are our endemic birds – those that are found only in the Fiji Islands. Fiji has 27 endemic birds, comprising nearly half of our landbirds. There is just one endemic seabird, the Critically Endangered Fiji Petrel.

To emphasise how special our avifauna is, there are few countries in the world with a higher proportion of endemic birds than Fiji. Indeed the island of Kadavu, with four endemic birds, has the highest number of endemic birds per land area in the world.

“While our state of knowledge of Fiji’s birds is better than for many other groups, it is still relatively poor, and we have yet to introduce any form of national monitoring”, said Dick Watling, the report’s author.

“Some species such as the Fiji Petrel and the Red-throated Lorikeet [both Critically Endangered] remain amongst the rarest birds in the world. We have a good idea of the reasons why they are so rare – largely due to invasive predators but there are no national resources to undertake conservation action”.

Migrant shorebirds and voyaging seabirds are a distinctive and culturally important component of the Fijian avifauna. In September each year, the Bar-tailed Godwits arrive at Suva Point. As far as we know, they fly direct from Alaska to Suva, a non-stop journey of eight to nine days. Some fly direct from Alaska to New Zealand, an 11-day non-stop flight.

The migrations that our dilio (Pacific Golden Plover), Bar-tailed Godwits and other shorebirds undertake twice a year are marvels of the natural world.

“Unfortunately, one of the most important feeding sites for these shorebirds – the mudflats of Suva Point are under consideration for reclamation”, noted Dr Watling. “Where then will these shorebirds rest and prepare for their return journey?”

‘Fiji: State of Birds 2013′ is the latest in a growing collection of national BirdLife reports from around the globe. These publications draw on national survey and monitoring data to provide a detailed and authoritative insight into the status of and pressures faced by birds and biodiversity in specific countries, with inspiring examples of conservation actions being undertaken by BirdLife Partners and others.

To download the ’Fiji: State of Birds 2013, please click here (pdf. 4.9 mb). To find out more about BirdLife’s State of the nation’s birds report, please click here.

The British Government have launched a new BirdLife project to conserve Fiji’s forest. “It is a great pleasure for us at the High Commission, together with our partners at BirdLife International, to the launch a new three-year project here in Fiji,” said Mr Dan Salter – Deputy High Commissioner of the United Kingdom to Fiji: here.