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Jovialis
08-05-18, 01:43
https://i.imgur.com/oQWabQS.jpg

Alligators on the beach. Killer whales in rivers. Mountain lions miles from the nearest mountain.

In recent years, sightings of large predators in places where conventional wisdom says they "shouldn't be" have increased, in large part because local populations, once hunted to near-extinction, are rebounding—thanks to conservation.

Many observers have hypothesized that as these populations recover the predators are expanding their ranges and colonizing new habitats in search of food.

A Duke University-led paper published today in the journal Current Biology suggests otherwise.

It finds that, rather than venturing into new and alien habitats for the first time, alligators, sea otters and many other large predators—marine and terrestrial species alike—are re-colonizing ecosystems that used to be prime hunting grounds for them before humans decimated their populations and well before scientists started studying them.

"We can no longer chock up a large alligator on a beach or coral reef as an aberrant sighting," said Brian Silliman, Rachel Carson Associate Professor of Marine Conservation Biology at Duke's Nicholas School of the Environment. "It's not an outlier or short-term blip. It's the old norm, the way it used to be before we pushed these species onto their last legs in hard-to-reach refuges. Now, they are returning."

By synthesizing data from recent scientific studies and government reports, Silliman and his colleagues found that alligators, sea otters, river otters, gray whales, gray wolfs, mountain lions, orangutans and bald eagles, among other large predators, may now be as abundant or more abundant in "novel" habitats than in traditional ones.

Their successful return to ecosystems and climatic zones long considered off-limits or too stressful for them upends one of the most widely held paradigms of large animal ecology, Silliman said.

"The assumption, widely reinforced in both the scientific and popular media, is that these animals live where they live because they are habitat specialists. Alligators love swamps; sea otters do best in saltwater kelp forests; orangutans need undisturbed forests; marine mammals prefer polar waters. But this is based on studies and observations made while these populations were in sharp decline. Now that they are rebounding, they're surprising us by demonstrating how adaptable and cosmopolitan they really are," Silliman said.

For instance, marine species such as sting rays, sharks, shrimps, horseshoe crabs and manatees now make up 90 percent of alligators' diet when they're in seagrass or mangrove ecosystems, showing that gators adapt very well to life in a saltwater habitat.

The unanticipated adaptability of these returning species presents exciting new conservation opportunities, Silliman stressed.

"It tells us these species can thrive in a much greater variety of habitats. Sea otters, for instance, can adapt and thrive if we introduce them into estuaries that don't have kelp forests. So even if kelp forests disappear because of climate change, the otters won't," he said. "Maybe they can even live in rivers. We will find out soon enough."

As top predators return, the habitats they re-occupy also see benefits, he said. For instance, introducing sea otters to estuarine seagrass beds helps protect the beds from being smothered by epiphytic algae that feed on excess nutrient runoff from inland farms and cities. The otters do this by eating Dungeness crabs, which otherwise eat too many algae-grazing sea slugs that form the bed's front line of defense.

"It would cost tens of millions of dollars to protect these beds by re-constructing upstream watersheds with proper nutrient buffers," Silliman said, "but sea otters are achieving a similar result on their own, at little or no cost to taxpayers."

Read more at: https://phys.org/news/2018-05-large-predators-near-extinction-unexpected.html#jCp




Are the ghosts of nature’s past haunting ecology today?
Humans have decimated populations of large-bodied consumers and their functions in most of the world’s ecosystems. It is less clear how human activities have affected the diversity of habitats these consumers occupy. Rebounding populations of some predators after conservation provides an opportunity to begin to investigate this question. Recent research shows that following long-term protection, sea otters along the northeast Pacific coast have expanded into estuarine marshes and seagrasses, and alligators on the southeast US coast have expanded into saltwater ecosystems, habitats presently thought beyond their niche space. There is also evidence that seals have expanded into subtropical climates, mountain lions into grasslands, orangutans into disturbed forests and wolves into coastal marine ecosystems. Historical records, surveys of protected areas and patterns of animals moving into habitats that were former hunting hotspots indicate that — rather than occupying them for the first time — many of these animals are in fact recolonizing ecosystems. Recognizing that many large consumers naturally live and thrive across a greater diversity of ecosystems has implications for setting historical baselines for predator diversity within specific habitats, enhancing the resilience of newly colonized ecosystems and for plans to recover endangered species, as a greater range of habitats is available for large consumers as refugia from climate-induced threats.

https://www.cell.com/current-biology/fulltext/S0960-9822(18)30430-5?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com %2Fretrieve%2Fpii%2FS0960982218304305%3Fshowall%3D true

Angela
08-05-18, 16:41
https://i.imgur.com/oQWabQS.jpg

Alligators on the beach. Killer whales in rivers. Mountain lions miles from the nearest mountain.

In recent years, sightings of large predators in places where conventional wisdom says they "shouldn't be" have increased, in large part because local populations, once hunted to near-extinction, are rebounding—thanks to conservation.

Many observers have hypothesized that as these populations recover the predators are expanding their ranges and colonizing new habitats in search of food.

A Duke University-led paper published today in the journal Current Biology suggests otherwise.

It finds that, rather than venturing into new and alien habitats for the first time, alligators, sea otters and many other large predators—marine and terrestrial species alike—are re-colonizing ecosystems that used to be prime hunting grounds for them before humans decimated their populations and well before scientists started studying them.

"We can no longer chock up a large alligator on a beach or coral reef as an aberrant sighting," said Brian Silliman, Rachel Carson Associate Professor of Marine Conservation Biology at Duke's Nicholas School of the Environment. "It's not an outlier or short-term blip. It's the old norm, the way it used to be before we pushed these species onto their last legs in hard-to-reach refuges. Now, they are returning."

By synthesizing data from recent scientific studies and government reports, Silliman and his colleagues found that alligators, sea otters, river otters, gray whales, gray wolfs, mountain lions, orangutans and bald eagles, among other large predators, may now be as abundant or more abundant in "novel" habitats than in traditional ones.

Their successful return to ecosystems and climatic zones long considered off-limits or too stressful for them upends one of the most widely held paradigms of large animal ecology, Silliman said.

"The assumption, widely reinforced in both the scientific and popular media, is that these animals live where they live because they are habitat specialists. Alligators love swamps; sea otters do best in saltwater kelp forests; orangutans need undisturbed forests; marine mammals prefer polar waters. But this is based on studies and observations made while these populations were in sharp decline. Now that they are rebounding, they're surprising us by demonstrating how adaptable and cosmopolitan they really are," Silliman said.

For instance, marine species such as sting rays, sharks, shrimps, horseshoe crabs and manatees now make up 90 percent of alligators' diet when they're in seagrass or mangrove ecosystems, showing that gators adapt very well to life in a saltwater habitat.

The unanticipated adaptability of these returning species presents exciting new conservation opportunities, Silliman stressed.

"It tells us these species can thrive in a much greater variety of habitats. Sea otters, for instance, can adapt and thrive if we introduce them into estuaries that don't have kelp forests. So even if kelp forests disappear because of climate change, the otters won't," he said. "Maybe they can even live in rivers. We will find out soon enough."

As top predators return, the habitats they re-occupy also see benefits, he said. For instance, introducing sea otters to estuarine seagrass beds helps protect the beds from being smothered by epiphytic algae that feed on excess nutrient runoff from inland farms and cities. The otters do this by eating Dungeness crabs, which otherwise eat too many algae-grazing sea slugs that form the bed's front line of defense.

"It would cost tens of millions of dollars to protect these beds by re-constructing upstream watersheds with proper nutrient buffers," Silliman said, "but sea otters are achieving a similar result on their own, at little or no cost to taxpayers."

Read more at: https://phys.org/news/2018-05-large-predators-near-extinction-unexpected.html#jCp

That's all very nice and all, but I don't want alligators over-running my beach front, and ranchers out west are shooting gray wolves who attack their animals.

Angela
08-05-18, 16:46
That's all very nice and all, but I don't want alligators over-running my beach front, and ranchers out west are shooting gray wolves who attack their animals.

Some extreme animal conservationists remind me of my Aunt Caterina. She was a hippy born decades before they existed. She had a house alongside a canal in Florida. Every afternoon, "Mr. Alligator" used to climb up to have a nap in the sun. :petrified::rolleyes2:

Finally some neighbor called animal control. There were people living there who had children for goodness' sakes.

I cannot begin to explain how she irritated me. I thought she had the maturity of a ten year old, and she was 70 at the time!

Jovialis
08-05-18, 17:17
That's all very nice and all, but I don't want alligators over-running my beach front, and ranchers out west are shooting gray wolves who attack their animals.

Yeah, I can imagine there's going to be a big issue with these animals coming into contact with humans.

People will have to take measures to safeguard themselves if this is going to be the new norm. However, these animals populations should be controlled to not overlap into human habitats.

Jovialis
08-05-18, 17:39
I found this part of the the article to be particularly interesting:

"The assumption, widely reinforced in both the scientific and popular media, is that these animals live where they live because they are habitat specialists. Alligators love swamps; sea otters do best in saltwater kelp forests; orangutans need undisturbed forests; marine mammals prefer polar waters. But this is based on studies and observations made while these populations were in sharp decline. Now that they are rebounding, they're surprising us by demonstrating how adaptable and cosmopolitan they really are," Silliman said."

Salento
08-05-18, 18:05
In the news yesterday.
Updated 2 hours ago.
Crocodile bites off bride's arm days before wedding in Zimbabwe. They married anyway.
https://www.usatoday.com/story/news/nation-now/2018/05/08/crocodile-bites-brides-arm-off-days-before-wedding-zimbabwe-river/589536002/

davef
08-05-18, 18:36
I think mountain lions are cute

Salento
08-05-18, 19:44
I think mountain lions are cute

I think for mountain lions you’re tasty
(Sorry, going back on topics) :)

Maciamo
09-05-18, 08:08
I am not surprised that alligators should be found on beaches. After all crocodiles in Australia are often found on beaches too. That's part of their natural habitat.


Silliman and his colleagues found that alligators, sea otters, river otters, gray whales, gray wolfs, mountain lions, orangutans and bald eagles, among other large predators, may now be as abundant or more abundant in "novel" habitats than in traditional ones.

Since when are otters large predators? And why would they think that orangutans are predators at all? They are vegetarians!

Yetos
09-05-18, 10:22
I think future belongs to Insects

Gloabal warming ( I belive it exists, I doupt about the numbers given)
is their ally to conquer the world,

http://1.bp.blogspot.com/-A3xGxAxZvOE/VjoUcPp68FI/AAAAAAAAtPg/qizrktNKtw0/s1600/bluecrab.jpg


http://i.dailymail.co.uk/i/pix/2017/09/01/02/43C4973E00000578-0-image-a-1_1504230370346.jpg

davef
09-05-18, 13:38
Why should anyone even worry about large predators? It should be much easier to defend yourself against a bear these days, just take out a pistol and blow its head off.

Salento
09-05-18, 15:32
Think you can protect yourself from a Bear with a gun? Forget it


“ ... According to research by the US Fish and Wildlife Service, of those who defended themselves against a bear attack with a weapon, 50% sustained serious injuries – compared to very few injuries incurred by those defending themselves with bear spray. In two studies published in 2008 and 2012 by bear researchers Tom Smith, a professor at BYU, and Stephen Herrero, professor emeritus at the University of Calgary and author of Bear Attacks: Their Causes and Avoidance, the profound efficacy of bear spray versus weapons has been proven beyond a doubt.

————-
Be Alert
Leave your damn earbuds in the car and be alert to every sound and movement.
Make noise. Unfortunately, hiking quietly endangers you. Call out and clap your hands frequently. Sing loudly.
Beware of blind corners and loud streams where a bear may not see or hear you.
Hike in groups of at least three people.
Carry bear spray! Repeat. Carry bear spray!
If you do everything right and you still run into one ...
Do not try to get closer to take a picture!
Do not run. You’re acting just like prey.
Slowly pull out your bear spray and remove the safety lock.
If it is a black bear, gather together, stand tall and make lots of noise.
If it’s a grizzly, remain still and calm. Properly position the bear spray in your hand.
Speak in an appeasing voice and very slowly back away.
An agitated grizzly may pop its jaws and pound the ground with its paws. It may also lunge toward you in a bluff charge. Do not use your pepper spray unless the bear is within twenty-five feet.
If the bear charges, aim the nozzle of the spray just above the bear’s head and give a sustained blast. ... ”

https://www.theguardian.com/environment/2016/jul/21/what-to-do-bear-encounter-attack

exceededminimumso..
09-05-18, 17:05
How to tell black bears and grizzlies apart? Climb up a tree. If it climbs up after you, it's a black bear. If it knocks the tree down, it's a grizzly.

Yetos
10-05-18, 12:33
Why should anyone even worry about large predators? It should be much easier to defend yourself against a bear these days, just take out a pistol and blow its head off.

bears will extinc,
few polars in pole,
and rest in siberia and Zoo's

but shoot a spider?
new tropical snakes?
etc

davef
10-05-18, 12:40
bears will extinc,
few polars in pole,
and rest in siberia and Zoo's

but shoot a spider?
new tropical snakes?
etc

I would love to fight a giant spider. A shotgun or flame thrower should finish it off best.
There are legal flame throwers, should also be effective against snakes.

LABERIA
10-05-18, 12:45
I would love to fight a giant spider. A shotgun or flame thrower should finish it off best.
There are legal flame throwers, should also be effective against snakes.
Like this?

https://ia.media-imdb.com/images/M/MV5BZjVkYjc4M2ItYWMyZi00MDI4LTkyM2YtMWQ4MTEwNWU0MD [email protected]@._V1_.jpg

davef
10-05-18, 12:46
Like this?

https://ia.media-imdb.com/images/M/MV5BZjVkYjc4M2ItYWMyZi00MDI4LTkyM2YtMWQ4MTEwNWU0MD [email protected]@._V1_.jpg

Exactly! Like that. I want one as a pet. If I raise it from birth, it might respect me, especially if I feed it it's daily cow.

davef
10-05-18, 13:25
Or at least one the size of a dog. I would name mine Lucifer and walk him on a leash

Salento
10-05-18, 13:38
Exactly! Like that. I want one as a pet. If I raise it from birth, it might respect me, especially if I feed it it's daily cow.

Hey, Spiders are my thing, find yourself another Giant Pet!

https://i.imgur.com/tv3ttz8_d.jpg?maxwidth=640&shape=thumb&fidelity=medium

https://i.imgur.com/hixLJ8G_d.jpg?maxwidth=640&shape=thumb&fidelity=medium
LOL LOL :)