Displaying items by tag: Irish Whale and Dolphin Group
The studies, part funded by the US Navy, found that beaked whales where particularly sensitive to sonar - and that even blue whales, the largest animals on earth, were distracted from feeding by the subsurface noise.
It's long been feared that the use of sonar is to blame for unusual behaviour among whales, who navigate and communicate with each other over long distances using sound.
As previously reported on Afloat.ie, the Irish Whale and Dolphin Group (IWDG) identified sonar activity by Royal Navy submarines as a possible cause of a the mass stranding of pilot whales in Donegal in November 2010, in which as many as 35 whales died.
Now for the first time, sonar has been proven to affect behaviour of cetaceans to a detrimental degree, confirming for many a connection between the use of sonar technology and recordings of whale and dolphin strandings identified since the 1950s. The Guardian has much more on the story HERE.
In more positive whale-related news, the IWDG reports that its next Cape Clear summer whalewatching course over the weekend of 26-28 July is "filling up nicely".
Places are still available but as it coincides with the tourism high season in West Cork, anyone interested is advised to book sooner than later to ensure they have someone to stay nearby.
The most recent weekend course over the June bank holiday witnessed numerous harbour porpoises and common dolphins, but its hoped the elusive whales will make an appearance next time round!
#MarineWildlife - In a week that saw the Isle of Man's first sighting of a humpback whale for three years, BBC News reports on the strange discovery of a rare species of dolphin two miles inland from the shore in Co Donegal.
The carcass of an Atlantic white-sided dolphin was found on a hillside near Meenbanad with head injuries - but no one knows how it got there.
Pádraig Whooley of the Irish Whale and Dolphin Group (IWDG) said it's most likely that someone found the dead cetacean on the beach and took it to the hillside to decay so that its skeleton could later be retrieved.
The dolphin is thought to be one of a pod that beached at Traigheanna Bay in Dungloe on 21 June. The species is a rare sight in Irish coastal waters, said Whooley, because they tend to feed much further out at sea.
In other stranding news, the IWDG reports that a bottlenose dolphin who live stranded at Beal in Co Kerry last summer has been recorded in the Shannon Estuary with her calf on a number of occasions this month and last.
The Shannon Dolphin and Wildlife Foundation has more on the sightings of the dolphin they now call Sandy Salmon.
As the Shannon Dolphin and Wildlife Foundation (SDWF) reports, the dolphin known as 'No 1' was sighted in Brandon Bay on Saturday 25 May swimming in a group of three.
No 1 is happily a familiar sight in the region, having been recorded most years since the project began in 1993.
"It has long been known that Shannon dolphins regularly use Tralee and Brandon Bays but how important the area is in not clear," says the SDWF on its blog. "If we are to protect the Shannon dolphins we need to ensure we identify all their important habitats and extend protection to these areas if necessary."
Meanwhile, its been confirmed that the trio of bottlenose dolphins who took up residence near Bunratty Castle in the spring have been observed in the mainstream of the Shannon Estuary.
The three were spotted on the first monitoring trip of the summer from Kilrush last week by SDWF researchers of Moneypoint.
"This demonstrates again the value of long term monitoring and the power of a photo ID catalogue to monitor the Shannon dolphins," says the SDWF blog.
In other cetacean news, an in-depth discussion of the Shannon's dolphins and the Irish Whale and Dolphin Group's (IWDG) research of bottlenose dolphins around the Irish coastline was broadcast on Derek Mooney's afternoon show on RTÉ Radio 1 recently.
#MarineWildlife - Tonight's Nature on One on RTÉ Radio 1 joins the Irish Whale and Dolphin Group (IWDG) on a quest off Hook Head to find the majestic fin whale.
As TEN reports, Colin Stafford Jones was on board with the IEDG's Pádraig Whooley on a mission to track down the world's second largest animal - not only the biggest example of marine wildlife behind the incredible blue whale.
Their adventure will be broadcast tonight (Sunday 9 June) from 7pm on RTÉ Radio 1, and will be available to listen online afterwards via the Nature on One website HERE.
A ranger with the National Parks and Wildlife Service (NPWS) made the discovery at Aillebrack in Co Galway on the evening of 27 May.
The 5m carcass of a female - like the female and juvenile found in the northwest - is thought to be either a True's or Sowerby's beaked whale.
Mick O'Connell, strandings officer with the Irish Whale and Dolphin Group (IWDG), says the latest stranding "raises new questions", with suspicion that its death may be linked to the face of the Donegal pair earlier this month.
As previously reported on Afloat.ie, beaked whales are a rare occurrence in Irish waters, with the last record before this month' stranding made in 2009.
#MarineWildlife - A gray whale has been sighted many thousands of miles from its usual Pacific swimming grounds in the South Atlantic.
As Pádraig Whooley writes on the Irish Whale and Dolphin Group (IWDG) website, the whale was spotted in the last week in Walvis Bay, Namibia - only the second ever confirmed sighting of the marine species in the Atlantic Ocean, and the first south of the equator, since records began.
Previously a solitary gray whale was tracked in the Mediterranean in May 2010 from the coast of Israel to Barcelona in north-eastern Spain.
That was the first time a gray whale had been seen anywhere east of the Pacific Ocean following the presumed extinction of the Atlantic gray whale in the 17th century.
Whooley calls the latest sighting "a fascinating discovery" and says it "points strongly towards a dramatic shift in distribution facilitated by climate change.
"This is a timely reminder that we should never assume to know what species occur in our local waters, especially when this species seems to have literally come back from the dead."
#MarineWildlife - Seven dolphins and two beaked whales have stranded on beaches in the northwest in events described as "unusual" by the Irish Whale and Dolphin Group (IWDG).
On the Mullet Peninsula, a group of seven common dolphins - comprising five adults and two juveniles - live stranded at Tarmon Beach on Sunday 12 May.
Though initial attempts to refloat them were successful, one of the juveniles was later found dead and the other was euthanised due to poor health.
Meanwhile in Donegal, the fresh carcass of a female True's or Sowerby's beaked whale was found on Sunday evening on Five Fingers Stand at Inishowen - some days after a reported live stranding of a Sowerby's beaked whale on the Welsh coast.
The Inishowen stranding was followed yesterday 14 May by the discovery of a dead beaked whale calf at Trawbreaga Bay, in what is believed to be a connected stranding.
Samples of the adult female were taken in order to confirm the species, either of which would mark a rare cetacean record for Ireland - the first since 2009.
As the IWDG's Dr Simon Berrow relates, it was not an auspicious start on 2 May 1993 when the first research trip on the estuary returned after five hours without having seen a single cetacean.
But the following day brought a bounty, with 16 dolphins across three different groups located by the IWDG - the beginning of two decades of sightings and recordings for the Shannon Dolphin Project, which has identified around 230 individual dolphins to date.
Thanks to that project, we know today that at least six of those dolphins first seen in 1993 are still in the estuary as of last year.
The Shannon Dolphin Project now has a website explaining its achievements and the work of the Shannon Dolphin and Wildlife Foundation (SDWF) over the years.
Meanwhile, Afloat reader Karl Grabe has also produced a spectrogram and edit of hydrophone recordings captured by Dr Berrow of Shannon dolphins just a few weeks ago.
Grabe previously uploaded a wonderful snippet of dolphins vocalising in the estuary late last year.
Simon Berrow of the Irish Whale and Dolphin Group (IWDG) explained that it's not unusual for dolphins to forage for food in waterways that feed into the estuary, though they usually return to the main catchment on their own shortly after.
With fears that their acoustic abilities were impaired, preventing them from navigating downstream past a series of bridges and concrete pillars between them and the main watercourse, a rescue attempt had been planned for late last week.
But as the Clare People reports, this was called off as the dolphins were spotted less and less frequently in the area.
Later hydrophone tracking by the IWDG led experts to discover that the cetaceans were able to come and go as they pleased.
Despite this, dolphins only have a limited ability to survive in fresh water, and can develop serious kidney and skin problems if exposed for a significant length of time.
The Irish Whale and Dolphin Group (IWDG), which has been tracking the group, believes they originated from a larger group populating the estuary.
As the IWDG's Simon Berrow explains, such dolphins are known to forage for food in rivers that feed into the estuary, and will return to the main catchment on their own.
While the risk of stranding in the shallower waters of rivers is unlikely, there is growing concern that the dolphins have been in the area for longer than expected.
"We can't rule out the possibility that their acoustic abilities may be impaired by the series of bridges and concrete pillars that span one of the bridges, and that they may be finding it difficult to navigate as a result of an 'acoustic trap'," says Berrow.
The IWDG says it is in discussion with the National Parks and Wildlife Service as to what options are available to step in to shepherd the trio back to the Shannon Estuary if necessary.