Animals

[CaaC (John)+]

Quote

Return to humpback halcyon days?

The humpback whale’s recovery is one of the great conservation stories. Turns out it’s not the best news for everyone in the food chain.

One of the 21st century’s greatest ecological success stories, the dramatic recovery of humpback whales, may be leading to ecological complications, scientists say.

Not all that long ago, humpback whales were hunted to near-extinction, their populations plummeting so badly that by the mid-1980s, it was estimated that only 440 remained south of the Equator. Since then, whaling bans have not only saved humpbacks from extinction but allowed them to rebound. Today is thought there are nearly 80,000, worldwide.

It’s one of the world’s great ecological recovery stories… with one caveat. Humpback whales have to eat. And they are big, so they eat a lot. Which means that their recovery may affect marine ecosystems that had previously adapted to their absence – ecosystems that are also being stressed by the mounting effects of climate change.

“The problem is that as whales return to their old feeding and breeding grounds, researchers are unsure how [they] will impact communities that have changed in their absence,” says Emily Zembricki, an undergraduate researcher at Stockton University, New Jersey, US, who studied them in conjunction with Oscar Schofield of Rutgers University in nearby New Brunswick.

In an online presentation at the 2022 Ocean Sciences Meeting, Zembricki examined the effects of the humpbacks’ stunning recovery on krill in the waters offshore from the West Antarctic Peninsula.

Krill are small, shrimp-like crustaceans that form the base of much of the Antarctic food chain, not only for filter-feeding whales like humpbacks, but also for seals, penguins, seals, and fish. (They are also harvested by commercial fishing companies, mostly as feed sources for aquiculture.)

There are a number of species, but in the West Antarctic Peninsula waters, Zembricki was primarily interested in two of them: Euphausia superba, and various species of the genus Thysanoessa.

As the name “superba” might indicate, the former is relatively large, measuring about 60 millimetres long. The latter checks in at a more modest 30 mm.

Prior to 1993, Zembricki says, the big ones were dominant. Then, a warming event reduced the extent of sea ice for several years – important because E. superba (the large ones) are dependent on the ice, attaching to its base in their larval and juvenile stages, and relying on it to shield them from predators. With less ice, E. superba lost its dominance and was supplanted by Thysanoessa, which isn’t as reliant on ice for protection.

When the ice returned in 1999, however, Thysanoessa retained its dominance.

Why didn’t E. superba recover? One possibility, Zembricki says, is that a resurgent humpback whale population was eating all the krill it could find – and not caring what species they were. “Whales don’t pick and choose,” Zembricki says. “They just eat whatever is there.”

The result, she says, is that their increasing presence in West Antarctic waters perpetuated the climate-change-induced shift seen in 1993–98. And because the surviving krill are smaller, and therefore less nutritious, every animal feeding on them now has to spend more energy foraging in order to fulfill its dietary needs. “So, while this wasn’t something I explicitly looked at in my research, I know that the change in krill dominance also affects fish and the [other] animals that eat them,” Zembricki says.

Originally published by Cosmos as Return to humpback halcyon days?

 

[Tommy]

Otters try sparkling water for the first time. 

 

[CaaC (John)+]

 

 

[Bluewolf]

Revenge is best served cold - 9GAG

[MUFC]

 

[Rucksackfranzose]

2 hours ago, MUFC said:

 

Please be so kind and do me favour. We got a "women feet" thread, please spare us posts of your fetish in other threads,

Edited March 21, 2022 by Rucksackfranzose

[Azeem]

Imagine being the fastest land animal on earth but still hunting a pray that 50% of tines out runs you. 

[CaaC (John)+]

Quote

Baleen isotopes tell whale of a tale

Work matching isotope data drawn from whales’ diets to climate records reveals how the climate crisis is affecting the planet’s biggest creatures.

Baleen whales in the southern hemisphere are likely to face challenging conditions as climate change continues, new research from the University of New South Wales suggests.

The study used stable isotope data preserved in whale baleen – a bristly feeding apparatus made of keratin – to unlock information about feeding and migration patterns of humpback whales and southern right whales going back 60 years.

The researchers matched the isotope information with climate data to understand how climate cycles have been affecting the whales over the study period.

Their results indicate that La Niña events, such as the southern hemisphere has been experiencing this summer, can make life much more difficult for whales.

What a whale wants, what a whale needs

FULL REPORT

 

[nudge]

Went to a Turtle Conservation Center Today. Such fascinating animals... Met the marine biologists working there who explained their work procedures and gave a lot of general information on turtles. Also had a chance to help release the baby turtles into the wild! 

 

[CaaC (John)+]

Quote

The chilly origins of Australia’s egg-laying mammals
New research sheds light on the origin story of our mysterious monotremes

Australia’s mysterious monotremes are the world’s only living, egg-laying mammals. Today, they comprise just two species: the echidna and the platypus.

But these strange creatures are the last survivors of a much larger and more diverse set of species that once roamed the southern continents.

Now, a team of scientists, headed up by Australian Museum (AM) Chief Scientist Kristofer Helgen and AM honourary associate Tim Flannery, has unravelled the monotremes’ origin story, tracing them back to the chilly polar forests of an ancient world.

The research, published in Alcheringa: An Australasian Journal of Palaeontology, involved examining every significant monotreme fossil currently known, to chart their history and evolution. 

The researchers found that the oldest-known monotreme, Teinolophos trusleri, lived some 130 million years ago when south-eastern Australia lay close to the South Pole. This frigid polar landscape, perhaps surprisingly, still had forests which withstood at least three months of freezing darkness each year.

FULL REPORT

 

 

Edited March 30, 2022 by CaaC (John)
Spacing correction

[Bluewolf]

An African Hammerhead Bat... sod that flapping around the camp at night.. 

[nudge]

14 minutes ago, Bluewolf said:

An African Hammerhead Bat... sod that flapping around the camp at night.. 

At the first glance, I thought that was a moose  

[Coma+]

 

[nudge]

11 minutes ago, Coma said:

 

This is my second-favourite Twitter account

[Tommy]

[Coma+]

57 minutes ago, Tommy said:

They drive better than most people.

[Stan]

 

[Bluewolf]

So calm and casual for a little one... 

Psycho little girl! - 9GAG

 

[CaaC (John)+]

1 hour ago, Bluewolf said:

So calm and casual for a little one... 

Psycho little girl! - 9GAG

 

Would you pick one up? 

[Bluewolf]

Just now, CaaC (John) said:

Would you pick one up? 

I am alright with spiders but when they are that big I would be worried they might bite me so imagine I might feel a little uneasy once they start clambering about.. 

[CaaC (John)+]

2 minutes ago, Bluewolf said:

I am alright with spiders but when they are that big I would be worried they might bite me so imagine I might feel a little uneasy once they start clambering about.. 

I'm ok with spiders and I am our resident spider catcher here in the house, the biggest spider I have seen was in Australia when I was a young lad living in the bush, my mum would feed one that crawled down the outside wall and that was a tarantula. 

[Bluewolf]

6 minutes ago, CaaC (John) said:

I'm ok with spiders and I am our resident spider catcher here in the house, the biggest spider I have seen was in Australia when I was a young lad living in the bush, my mum would feed one that crawled down the outside wall and that was a tarantula. 

Not sure living in Australia would be a good fit for me.. I have a healthy respect for nature and just about everything out there can kill you.. 

[CaaC (John)+]

6 minutes ago, Bluewolf said:

Not sure living in Australia would be a good fit for me.. I have a healthy respect for nature and just about everything out there can kill you.. 

The only animal or insect whatever you want to call it I don't like is an earwig, I can remember as a young lad growing up in Tilbury, going into our coal shed, shaking a coal sack and a load of them would drop out with their backs up with their pinchers ready to bite, they made me shudder and I would run a mile.

Plus I heard that they got the name earwig from crawling into people's ears and nesting. 

[Bluewolf]

3 minutes ago, CaaC (John) said:

The only animal or insect whatever you want to call it I don't like is an earwig, I can remember as a young lad growing up in Tilbury, going into our coal shed, shaking a coal sack and a load of them would drop out with their backs up with their pinchers ready to bite, they made me shudder and I would run a mile.

Plus I heard that they got the name earwig from crawling into people's ears and nesting. 

I remember earwigs... 

Used to be a common sight when I was a kid but have not seen one for a great many years... 

[CaaC (John)+]

31 minutes ago, Bluewolf said:

I remember earwigs... 

Used to be a common sight when I was a kid but have not seen one for a great many years... 

Horrible little things them and like you, I have not seen one for years either, thank fuck.