Dolphin fossil discovery in New Zealand


This video is called Friday Fossil Mystery – Ep.2 – Dolphin Petrosal.

From the University of Otago in New Zealand:

New dolphin fossil found in NZ

Tuesday, 28 January 2014

A newly recognised fossil dolphin from New Zealand, dubbed Papahu taitapu, is the first of its kind ever found and may be a close relation to the ancestors of modern dolphins and toothed whales, according to University of Otago researchers.

Papahu lived 19–22 million years ago, and is one of the few dolphins to be reported globally dating to the start of the Miocene epoch. Judging from the size of its skull, Papahu was about two metres long, roughly the size of a common dolphin.

Dr Gabriel Aguirre and Professor Ewan Fordyce, from the University’s Department of Geology describe and interpret Papahu in the latest issue of Journal of Vertebrate Paleontology. This work was part of Dr Aguirre’s PhD research.

Dr Aguirre says that like most living dolphins, Papahu had many simple conical teeth, but its head was probably a bit wider, and not as high-domed. It lived at a time of global warmth, in shallow seas around Zealandia – or proto-New Zealand – along with ancient penguins and baleen whales.

The skull, one jaw, and a few other parts of Papahu taitapu were found in marine sedimentary rocks in the Cape Farewell region of northern South Island. The researchers used the Māori name ‘taitapu’ to honour this region, and ‘Papahu’ is a Māori name for dolphin. Only a single specimen has been found so far and the fossil is housed in the University’s Geology Museum.

“Our study of structures of the skull and earbone suggest that Papahu could make and use high frequency sound to navigate and detect prey in murky water. They probably also used sound to communicate with each other,” says Dr Aguirre.

Features of the Papahu skull can be used to analyse relationships with other dolphins and toothed whales. That work shows that the skull is distinct from all previously-reported fossils, which is why the dolphin can be formally named as a new form, he says.

“When we compared Papahu with both modern and fossil dolphins we found that it belongs in a diverse and structurally variable group of ancient dolphins that evolved and spread world-wide 19–35 million years ago. All of those ancient dolphins including Papahu and others, such as shark-toothed dolphins, are now extinct,” says Professor Fordyce.

“They have been replaced by the ‘modern’ dolphins and toothed whales, which diversified within the last 19 million years,” he says.

It is not clear, however, exactly why Papahu and other ancient dolphins went extinct, he added.

See also here.

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Spinner dolphin-striped dolphin hybrid discovery


This video from the USA is called Clymene Dolphins off Cape Hatteras, NC in May 2008, filmed by G. Armistead.

This video is called Untamed Americas: Spinner Dolphins.

From Wildlife Extra:

Rare natural hybridisation results in a dolphin with genetic similarities to both the spinner and striped

January 2014: A newly published study on the clymene dolphin, a small, sleek marine mammal living in the Atlantic Ocean, shows that this species arose through natural hybridisation between two dolphins species. In a molecular analysis including the closely related spinner and striped dolphins, scientists concluded that the clymene dolphin is the product a process that is common for plants, fishes and birds, but quite rare in mammals.

The study was conducted by to the Wildlife Conservation Society, the American Museum of Natural History, the Mote Marine Laboratory and the University of Lisbon.

“Our study represents the first such documented instance of a marine mammal species originating through the hybridisation of two other species,” said Ana R. Amaral, lead author of the study and research associate at the American Museum of Natural History. “This also provides us with an excellent opportunity to better understand the mechanisms of evolution.”

The classification of the clymene dolphin has been a longstanding challenge to taxonomists, who initially considered it to be a subspecies of the spinner dolphin. Then in 1981, thorough morphological analyses established it as a recognised distinct species. In the current study, researchers sought to clarify outstanding questions about the dolphin’s origin and relationships with rigorous genetic analyses.

Based on research conducted at the American Museum of Natural History’s Sackler Institute for Comparative Genomics, the authors examined the nuclear and mitochondrial DNA from skin samples obtained from both free-ranging dolphins by means of biopsy darts and deceased dolphins obtained through stranding events. Specifically, the team discovered that while the mitochondrial genome of the clymene dolphin most resembled the striped dolphin, the nuclear genome revealed a closer relation to the spinner dolphin. The findings reveal not only more about the species, but how natural hybridisation can create an entirely new species of mammal over time.

The clymene dolphin grows up to nearly 7ft in length and inhabits the tropical and temperate waters of the Atlantic Ocean. Threats to the species include incidental capture as by catch in fishing nets, which in some parts of the range has turned into direct hunts for either human consumption or shark bait.

This video is called Striped Dolphin Species Identification.

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Rare dolphins near English Farne Islands


This video from England says about itself:

Dolphins swimming off the Farne Islands.

Filmed from Glad Tidings VI on the 16th November 2013.

Wow!

These are bottlenose dolphins.

This video from England says about itself:

2 Common Dolphins at the Farne Islands on November 17th 2013 playing with the bow of the boat and then following other boats all the way into Seahouses harbour.

And this video from England says about itself:

2 Common Dolphins in the harbour of Seahouses on Nov 17th 2013. Filmed from Serenity II.

From the Serenity blog in England (with photos there):

Common Dolphins 17/11/2013

This blog should have been out a week ago but I suppose it better late than ever.

Anyway last Sunday (17th) I was on a 1.5 hour trip around the Farne Islands when my friend Ron gave me a shout saying that he had seen 2 dolphins at the Blue Caps.

I was nearly at Staple Island and I was praying that they would wait for us to arrive. By the time I got there they had been around all the boats and even a diver of Toby’s boat said that one of them swam straight past him.

As I got closer I could see about 6/7 Seals playing on the surface and then the 2 Dolphins came jumping out of the water.

I could not believe what I was witnessing and in my wildest dreams I never thought dolphins and seals would play together, but it looked like they were having so much fun until I turned up.

The pair left the seals and started to bow ride the boat. At first they were way ahead of the boat so I went a little faster and they seemed to enjoy it a bit more. They were really showing off so I went a little bit faster until I was doing 20 knots and they kept up with the boat. Now that is some speed and I don’t know how fast they can go but whatever the speed is 20 knots is very impressive.

They stayed with us for a while and then disappeared, so we turned around and headed over towards the seals.

Once we arrived back at the harbour I was praying that they would still be there for our next guests and as we steamed out of the harbour I noticed my cousin pointing at the bow of his boat. As I looked to see what he was meaning the dolphins jumped out of the water. They had followed him all the way back to the harbour and as I stopped they just followed him into the harbour. I could not believe they were actually in the harbour.

Another boat turned up and then another and at one stage we had 4 boats viewing the 2 dolphins swimming around us all.

I have never in my life seen dolphins in the harbour and to make it even better it was Common Dolphins, which have never been seen in Northumberland since 1989 and a first for the Farne Islands.

As I finished my last trip of the day and they were still outside the harbour until dark. A great record for the Farne Islands and hopefully not the last.

Sorry as all my pictures were taken on a mobile as I left my camera at home.

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Caribbean whales, dolphins and sharks


This video says about itself:

Whales in the Caribbean off Antigua and Barbuda

Humpback whales pass through the island chain each year giving those of us doing tours and charters something to look forward to. Yesterday we switched off the engines in very still conditions and had the pleasure of spending over 30 minutes with a mother and her calf. Some of the passengers on the boat couldn’t be held back and went over to snorkel with them. We made sure to keep good distance, but the inquisitive whales came very close to us to give us a good look.

Researchers of IMARES Wageningen UR in the Netherlands report about airplane based research, early November this year, in the Caribbean, in the sea around Aruba, Bonaire and Curaçao islands.

From the plane, they saw humpback whales, common bottlenose dolphins and rough-toothed dolphins. Also marine mammals which might be either Atlantic spotted dolphins, or pantropical spotted dolphins. These two species look very much alike from the air.

They saw sea turtles, rays and birds as well.

A whale shark was seen north of Aruba; and a basking shark north of Curaçao.

New dolphin species discovery in Australia


This video is called First Film of Rare Humpback Dolphins with Bottlenose Dolphins in Watamu, Kenya.

From Wildlife Extra:

New dolphin species discovered

Scientists find that dolphin in Australian waters is a new species

October 2013: A new, fourth, species of a humpback dolphin has been identified in the waters off northern Australia says a team of researchers from the Wildlife Conservation Society and the American Museum of Natural History. Humpback dolphins are named after a peculiar hump found just below the dorsal and live within river deltas, estuaries and coastal waters throughout the Indian, Pacific and eastern Atlantic oceans.

This wide geographic spread has led to the evolution of different species and till now scientists knew of three; the Atlantic humpback dolphin (Sousa teuszii) that lives in the eastern Atlantic off West Africa, the Indo-Pacific humpback dolphin (Sousa plumbea), which ranges from the central to the western Indian Ocean, another species of Indo-Pacific humpback dolphin (Sousa chinensis) that inhabits the eastern Indian and western Pacific Oceans.

“This discovery helps our understanding of the evolutionary history of this group and informs conservation policies to help safeguard each of the species,” said Dr. Martin Mendez, assistant drector of WCS’s Latin America and the Caribbean Program and lead author of the study.

The humpback dolphin grows up to eight feet in length and ranges from dark grey to pink and/or white in colour. The Atlantic humpback is “Vulnerable” according to the IUCN Red List, whereas the Indo-Pacific species is listed as “Near Threatened.” Humpback dolphins are threatened by habitat loss and fishing activity.

“New information about distinct species across the entire range of humpback dolphins will increase the number of recognized species, and provides the needed scientific evidence for management decisions aimed at protecting their unique genetic diversity and associated important habitats,” said Dr. Howard Rosenbaum, Director of WCS’s Ocean Giants Program.

Toxic whale, dolphin meat


This video says about itself:

Mercury Poisoning in Whale Meat, Seal Meat, Fish – Japanese Minamata Incident

21 aug 2009

Whale Meat, Seal Meat, and Seafood contain huge doses of Methyl Mercury – a neurotoxin. Eating Whale meat, Seal Meat, & Fish contaminated with Methyl or Organic elemental Mercury causes brain damage, mental retardation, tremors, and brain tissue damage. Most people are aware of health officials’ warnings about fish; however, thousands are unaware that the dosages contained in Whale Meat and Seal Meat is from 10x to 9,000x the dose in fish. Thousands of times above the human limit.

Even worse, some are unaware that eating whale meat, seal meat, and seafood can cause damage to their genitals, cause their future children to be born deformed, or result in their child being born learning disabled. Even 1 ingestion of this material has been shown to cause human damage.

The horrible effects of Mercury Poisoning from eating sea food was exemplified by the Minamata disaster in Japan, where Japanese ingested fish contaminated with the substance. Recall that the levels contained in Seal meat in Canada, and Whale Meat obtained by Japanese whalers are 10 to thousands of times the levels in fish. By the time a human ingests the whale meat or seal meat, the seal or whale has ingested thousands upon thousands of fish, and builds up using a process known as Bio-Accumulation. Japanese, Inuit, Norwegians, and Faroese who have ingested whale and seal meat are now so contaminated, that their tissue samples can be classified as hazardous waste.

Chronic metal toxicity is a concern in the Canadian Arctic. The findings of high metal levels in wildlife, marine mammals, and the fact that these are used as traditional food by Newfoundlanders and Natives constitutes a major threat to human health. We examined exposure to trace metals through traditional food resources for Inuit living in the eastern Arctic. Mercury, cadmium, and lead were found in local food resources as normally prepared and then eaten. Elevated concentrations of mercury ( ~ 50 micrograms/100 g) were found in seal liver, narwhal mattak, whale meat, and beluga mattak, and relatively high concentrations of cadmium and lead ( ~ 100 micrograms/100 g) were found in seal meat.

Any person supporting the Seal hunt is hurting Inuit, and Canadian citizens who ingest seal flipper or any type of seal meat, or omega3 seal oil product.

Any person supporting Japanese whalers is hurting Japan, hurting Japanese citizens, families, and children.

From Wildlife Extra:

Dangers of mercury in whale meat highlighted by new treaty

New mercury treaty to flag threats to human health of toxic whale & dolphin meat

October 2013. As the world’s first legally binding international treaty to curb the release of mercury into the environment has been signed, a coalition of NGOs urged countries to take immediate steps to address communities at particular risk of contamination from the consumption of whale and dolphin products.

Mercury contaminated meat

“For far too long, coastal communities around the world have been allowed to consume the mercury-contaminated meat of whales, dolphins and porpoises, many in ignorance of the risks involved,” said Clare Perry, Senior Campaigner at the UK-and US-based Environmental Investigation Agency (EIA).

“Now signatories to the new treaty must make communities in places as far afield as Japan and the Faroe Islands properly aware of the very serious risks to human health that come from eating the meat of toothed cetaceans.”

Minamata Convention on Mercury

The Minamata Convention on Mercury was adopted at the Conference of Plenipotentiaries in Minamata and Kumamoto, Japan. The choice of venue is significant as Minamata was the scene of the world’s worst-ever incident of mass mercury poisoning. The outbreak began in 1956 after methylmercury, discharged into the sea from a Chisso Corporation factory, accumulated in fish and shellfish and found its way into the human food chain.

Symptoms of mercury poisoning

Symptoms of mercury poisoning can include loss of muscular coordination, numbness in extremities, damage to hearing and speech, damage to foetal development, paralysis and death.

Dolphin meat in Japan

Dolphin meat sold for consumption in Japan has been found to have mercury levels as high as 98.9 parts per million, some 250 times higher than the Government regulatory level and higher than levels commonly found in the fish that caused Minamata disease.

“Governments have long been well aware of the dangers to human health that come from eating whale and dolphin meat contaminated with mercury and other pollutants, but in some cases they have been neglectfully reticent when it comes to properly protecting their citizens from the risks,” said Sakae Hemmi, of Japanese NGO Elsa Nature Conservancy.

Faroes pilot whales

Based on more than 20 years of medical studies in the Faroe Islands, scientists now advise that the meat of pilot whales killed there is no longer suitable for consumption – but Government recommendations have failed to follow such advice. In 2012, the International Whaling Commission (IWC) passed a consensus resolution noting such concerns and urging governments to take action.

1,300 pilot whales and dolphins killed in the Faroe Islands in 2013

Birgith Sloth, of the Society for the Conservation of Marine Mammals in Denmark, added: “Increasing awareness of the scientific advice has led to many in the Faroes rejecting pilot whale meat. Despite this, more than 1,300 pilot whales and white-sided dolphins have been killed in the Faroe Islands in 2013, suggesting that some people are consuming huge amounts of whale and dolphin meat. The Faroese Government needs to follow the advice of its own scientists and enforce a strict ban on consuming toxic whale meat”.

British dolphin rescued


This video says about itself:

Aug 22, 2013

A dolphin which had become stranded on sandbanks in the River Dee has been released into deeper water. Flint RNLI lifeboat launched at around 11.30am this morning and proceeded to Airbus UK’s loading facility, just downstream from Saltney Ferry.

The dolphin was in difficulty and required help to reach deeper waters.

With a representative from British Divers Marine Life Rescue on board to monitor its condition, the volunteer crew put the dolphin inside a stretcher and transferred her into the lifeboat.

The Flint inshore RNLI lifeboat headed towards Rhyl and was met by Rhyl all-weather lifeboat and the crew worked together to help release her in to deeper waters at Rhyl Flats.

From Wildlife Extra:

Common dolphin rescued from the River Dee

Dolphin refloated after stranding upriver

September 2013. After reports and photographs appeared on the internet appeared to show a common dolphin in the River Dee, British Divers Marine Life Rescue (BDMLR) service became concerned after the dolphin was reported to be mid-way to Chester.

Common dolphins prefer deeper waters and rarely enter rivers, but this animal may have been chasing fish into the Dee estuary and up the river. Once there, it may have experienced problems getting back out due to the high flooding tides associated with the local waters, especially on spring tides as currently.

BDMLR volunteers, along with members of the Coastguard and helpful members of the public, tracked the dolphin from the shore as it swam all the way up to Chester, and then turned back seawards. After a long day and many miles, it was seen heading out towards Flint in the estuary as daylight failed at around 9pm and the teams were stood down.

The following day BDMLR received a call to say that the dolphin was sadly back in the River close to Saltney. BDMLR volunteers, members of the Coastguard and locals again monitored its progress from the river banks and it repeated the journey of the previous day, swimming strongly and exhibiting feeding behaviour as had been observe[d] on previous days. It reached the Connah’s Quay area in late evening as the flooding tide entered the river and so was unable to swim back into the open sea.

Stranded

The next day it was again reported back in the river moving towards Chester, and subsequently the dolphin stranded about two miles away from Saltney.

An inshore lifeboat from Flint was called and the dolphin was made comfortable on board by a BDMLR team.

About 6 miles out to sea and in at least 18 metres of water, the female dolphin was put over the side of the lifeboat in a sling stretcher, with a couple of RNLI on either side to gently rock the dolphin as per BDMLR protocol. This helps to restore the animal’s equilibrium and recirculate any fluids that may have built up on one side. However, as the dolphin had not been stranded long, it gave all the right signs for release and as BDMLR medic Steve O’Connor on the lifeboat says, ‘went off like a rocket’ after a few minutes.

Dolphins enjoying whales’ company


A group of long-beaked common dolphins surf the bow wave of a migrating gray whale. This photo was shot by NOAA scientists off Southern California as they conducted their annual gray whale aerial survey. Credit: NOAA

From Wildlife Extra:

Migrating whales provide entertainment for dolphins – Photo

September 2013. In the photo, a group of long-beaked common dolphins are hitching a free ride on the bow wave of a migrating gray whale. Taken near Catalina Island off the coast of Southern California, the photo was shot from about 600 feet by scientists with the Cetacean Health and Life History Program at the US National Oceanic and Atmospheric Administration‘s (NOAA) Southwest Fisheries Science Center.

Migration

Every year, almost the entire population of eastern North Pacific gray whales migrates from their feeding grounds in the Arctic down to their breeding and calving grounds off the coast of Baja California, Mexico. And most years, NOAA scientists survey and photograph the whales from the air. By analysing the high-resolution photos, scientists can tell how well-nourished the animals are, how many females are pregnant, and how many new calves are born.

Health check

One reason for doing this is to keep an eye on the health of the gray whale population. But in addition to that, the photographic study is an indirect way of monitoring the Arctic ecosystem. The primary feeding grounds for the eastern north Pacific population of gray whales are in the Arctic. The rest of the year they fast or eat very little. So their physical condition during migration reflects conditions in their feeding grounds in the Arctic.

Climate change

“We know the Arctic is changing, and changing pretty rapidly,” said Wayne Perryman, a biologist with NOAA’s Cetacean Health and Life History Program. “We want to know how this is impacting the gray whale population.”

For example, many of the species that gray whales feed on are shifting northward as the Arctic warms. This means that gray whales have to migrate further north to feed. For pregnant females, who by the time they arrive in the Arctic have been fasting for many months, this extra travel may be energetically taxing. One of the things that Perryman and his colleagues are studying is the relationship between the length of the migration and the rate of successful pregnancies.

“Gray whales integrate the impacts of climate change into their physical condition, then they swim right by our coast,” said Perryman. “So we can actually do Arctic research right here from San Diego.”

For dolphins, however, migrating whales mean only one thing. And that’s a free ride.