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Re-discovery by nature conservancy team

According to NPR yesterday and our new channel today a team for the Nature Conservancy re-discovered this bird that was though to be extint for about half a century. This happened in Arkansas and there have been seven sightings. The find is supposed to be in this week's edition of Nature (If I remember right). This is absolutly amazing.
 
i find it interesting that no one else seems to care. comeon people lets see some enthusiasm
 
oh
 
That is definatly good news unless they are mistakely thinking the it is a Ivory instead of a Pileated. However, without the major efforts that have gone into saving the California Condor, this species still has little chance of surviving. If it has thaught to be extinct for such a long time period the gene pool must be very small. Hopefully some action is taken to photograph thaught findings and then further action is taken to build the population if it is found to be a true Ivory(s).
 
Gawd,

I think these people probably know the difference between a pileated and ivory billed...the field markings are very different!
 
[b said:
Quote[/b] ]species still has little chance of surviving
NONSENCE! There breeding and sucessfuly raising chicks in the wild totaly without human assistance (but heavy monitering and people ready to act if they see problems, and just sutch a case has happened) - captve bread birds breeding in the wild. Many safeguards and supplementary feeding incase food supplies fail for the relesed population in Arizona, the most sucessful this far

See Chatham Islands black robin HERE
 
[b said:
Quote[/b] (Finch @ April 28 2005,9:44)]
[b said:
Quote[/b] ]species still has little chance of surviving
NONSENCE! There breeding and sucessfuly raising chicks in the wild totaly without human assistance (but heavy monitering and people ready to act if they see problems, and just sutch a case has happened) - captve bread birds breeding in the wild. Many safeguards and supplementary feeding incase food supplies fail for the relesed population in Arizona, the most sucessful this far

See Chatham Islands black robin HERE
That is a very unique example, most species who's gene pool has deminished to that low of a level have little hope of surviving without human intervention. Actually at that extreme low of a level even with human help there is little to no chance of survival. Inbreeding brings out recessive traits, most species cannot survive such conditions.

And yes field marking are a good Identification method, tho many variations can occur in a species. I had slate colored dark eyed juncos here that had white stripes on their wings and their loreals(sp?) where also white. A very big difference from the standard Junco found here. Wouldn't it also be possible for the single spotted bird to have had a unique color pattern? Two white spots on the body wouldn't be to far fetch for a Pileated.

Don't take me the wrong way tho, I do hope the it is the Ivories. It would be great to have a species rediscovered. And I hope that the effort that has gone into saving the condor goes into saving them as well.
 
your logic, while mostly correct, is not only pessamistic but its also a bit too pessamistic and i will show you several examples in wich species have recovered from extreme lows without human help or continual intervention.

The Laysan duck has stood several times on the edge of extinction in tha hands of men but without being managed in any way (manegment started in 1953) its survival story is amazing. "species hovered on the brink of extinction between 1905 and 1930 when the population dropped to seven individuals and a single female. This decrease was largely due to a combination of hunting by guano mine workers and plume hunters followed by the introduction of European rabbits, which nearly wiped out all of Laysan Island's vegetation. As a result of this radical habitat degradation, three of the island's four endemic land birds went extinct. Lack of vegetative cover permitted erosion and blowing sand partially filled in the lake. The rabbits all subsequently starved to death, at which point the island began to revegetate" The species bounced back from this low to a  population of around 400 Without human help in any way. Recently the population has begun to sag again but there is evedence that the population fluctuates quite naturaly.

The Hihi (Stitchbird) became extinct on the main island of new zealand but some lingerd on at Little Barrier Island and has since flourished there, without human help, altough measures have been taken to improve nesting sucess by eradicating some introduced predators. despite our attempts, no other populations (those others are human reintroductions) to other islands are self-sustaining.


Many plant species resued by humans no longer need active manegment.



[b said:
Quote[/b] ]level have little hope of surviving without human intervention


The Chatham Islands black robin has self-sustaining populations on several islands and many no longer are managed, altough we are still reintroducing them to more islands and monitering the poulation. After the population has built up to a certain level we dont need to intervene any more unless we make a big boo-boo  like introducing predators that shouldnt be there-

like at guam, its forests are totaly silent from bird song because we introduced the brown treesnake.
 
Those species now dont need to have active manegement, they just need to be left alone now so we dont introduce pathogens pr predators witch wouldnt find their way there naturaly. HUMANS need active human manegment to curb the spread of diseases of wich we have little resistance to- ebola, anyone?

The goal of any conservation plan is 'To improve the conservation statusspecies endangered to rare by re-establishing them in their former ranges so that further intensive management is no longer required.' - the recovery potental varies widely between species but its certainly not impossible.


About the genetic thing, yes and no. Species can survive it, and the anscestors of many island species were descended from a few individuals that  found their way there. The same with introduced species like starlings- where is their inbreeding problems? tru there were 40 relesed but thats still not enough to prevent severe inbreeding
 
  • #10
True my view is pessamistic, but wouldn't that be the best way to look at it? If no action is taken to help the species survive are the chances going to be better then if people help?

I am sure there are more examples then the ones you listed, but how many species have gone extinct because of a decreased gene pool. How many have gone extinct because people haven't made an effort to help the species the survive? I am sure that the % is by far leaning my way.

[b said:
Quote[/b] ]After the population has built up to a certain level we dont need to intervene any more

Right, and shouldn't the same measures be taken to build up the population of these woodpeckers?

Quote From the link you provided
[b said:
Quote[/b] ]In 1976 there were a mere 7 birds left. These were all moved to Mangere Island where 120,000 trees had been planted to provide better shelter.

...and a foster species, the Chatham Island tits, ended up saving the black robin from extinction.
That is human assistance.

Individuals of the species were taken into captivity in the 1950's and the species initially bred quite well so that there are hundreds of Laysan Ducks in captive-breeding facilities in various parts of the world. There is some concern that the small initial numbers of individuals involved is now resulting in inbreeding depression problems in some captive populations. Birdlife International recommends establishing a new population on a suitable island to increase chances of species survival and this recommendation has been investigated by U.S. Geological Survey researchers. This idea has been bolstered by the finding using paleontologic evidence that Laysan Ducks once occurred throughout the Hawaiian Islands.

Tho the above paragraph is about birds in captivity it addresses the concerns of inbreeding.
 
  • #11
i never said the black robin was a case that was independent of human assistance- and laysan duck dissapeird due to polynesan settlements.

[b said:
Quote[/b] ]how many species have gone extinct because of a decreased gene pool?
Id like to know that myself but at the current time i kow of none that has actually gone extinct from it


[b said:
Quote[/b] ]Individuals of the species were taken into captivity in the 1950's and the species initially bred quite well so that there are hundreds of Laysan Ducks in captive-breeding facilities in various parts of the world
Im not leaving stuff out, the low occured from 1912 to 1930 and built up in the hundreds without human assistance, altough after that people were conserned so they beagan captive breeding when there was a reletevly high popultion built up in the '50s - this is not human assistance to get the species back from the brink, its a saftey net. The species does not need managment in the wild, it is a conscern in CAPTIVE populations.
 
  • #12
[b said:
Quote[/b] ]i never said the black robin was a case that was independent of human assistance- and laysan duck dissapeird due to polynesan settlements.
[b said:
Quote[/b] ] NONSENCE! There breeding and sucessfuly raising chicks in the wild totaly without human assistance (but heavy monitering and people ready to act if they see problems, and just sutch a case has happened) - captve bread birds breeding in the wild. Many safeguards and supplementary feeding incase food supplies fail for the relesed population in Arizona, the most sucessful this far

See Chatham Islands black robin HERE

Sure looks like that is what you where saying there.
And if you weren't then what was the point of your first reply to me?

[b said:
Quote[/b] ] Im not leaving stuff out, the low occured from 1912 to 1930 and built up in the hundreds without human assistance, altough after that people were conserned so they beagan captive breeding when there was a reletevly high popultion built up in the '50s - this is not human assistance to get the species back from the brink, its a saftey net. The species does not need managment in the wild, it is a conscern in CAPTIVE populations.

Yes that is what I said.

[b said:
Quote[/b] ]Individuals of the species were taken into captivity in the 1950's and the species initially bred quite well so that there are hundreds of Laysan Ducks in captive-breeding facilities in various parts of the world. There is some concern that the small initial numbers of individuals involved is now resulting in inbreeding depression problems in some captive populations. Birdlife International recommends establishing a new population on a suitable island to increase chances of species survival and this recommendation has been investigated by U.S. Geological Survey researchers. This idea has been bolstered by the finding using paleontologic evidence that Laysan Ducks once occurred throughout the Hawaiian Islands.

Tho the above paragraph is about birds in captivity it addresses the concerns of inbreeding.

[b said:
Quote[/b] ]Pinpointing the causes of extinction has long been a controversial issue among scientists. Some have argued inbreeding is the critical factor leading to a species' demise, while others maintain environmental conditions such as habitat loss are the more important players in extinction.

But a team of researchers at the Illinois Natural History Survey and the University of Illinois have shown the answer is probably a combination of both factors.

"I think this is going to put a nail in the coffin of separating the parts of genetic and nongenetic factors when talking about extinction," said L. Scott Mills, a wildlife ecologist at the University of Montana who commented on the study in the journal Science.

"What they have done is swing the pendulum back toward the middle," he said in a telephone interview, adding the study is one of the first to fully document examples of the complex interactions between the factors that push a population toward extinction.

Over 35 years the researchers tracked the reproductive success, genetic makeup and total number of Illinois prairie chickens, which numbered 2,000 in 1962 but had fallen to fewer than 50 by 1994.

As the prairie chicken population decreased, genetic variation diminished, Mills said. A lack of genetically different mates led to subtle changes in birth and survival rates and made it less likely an egg would hatch, which helped speed the birds' demise, he explained.

But the study also pointed out inbreeding alone does not lead to extinction. Habitat loss and other environmental factors play an important role in diminishing a population to a level where inbreeding can quicken extinction, said Ronald Westemeier, a wildlife ecologist, who led the study.

"We believe the near-complete loss of suitable grasslands and satellite populations in the region drove the greater prairie chicken toward this scenario," the authors wrote in Science.

There is also evidence that once a population size tumbles far enough it can reach a point of no return where nothing can counter the effects of inbreeding, Westemeier said.

The Illinois prairie chicken population only rebounded when the researchers diversified the gene pool by importing birds from neighboring states. This showed the importance of maintaining sufficient genetic resources for a species survival, Westemeier pointed out.

"All we are saying is you reach a critical level in gene pool levels that will affect reproduction rates and no amount of habitat restoration can help anymore," Westemeier said.

Besides the Praire Chicken, Wolves and Elk are regularly traded among states to increase the genetic diversity of reintorduced populations.
 
  • #13
No. read my posts again. you said

[b said:
Quote[/b] ]most species who's gene pool has deminished to that low of a level have little hope of surviving without human intervention. Actually at that extreme low of a level even with human help there is little to no chance of survival. Inbreeding brings out recessive traits, most species cannot survive such conditions.
and i mentioned

the California condor because you used it as a example that it had little chance of survibing without human intervention thats what this
[b said:
Quote[/b] ]There breeding and sucessfuly raising chicks in the wild totaly without human assistance (but heavy monitering and people ready to act if they see problems, and just sutch a case has happened) - captve bread birds breeding in the wild. Many safeguards and supplementary feeding incase food supplies fail for the relesed population in Arizona, the most sucessful this far
was about that they were on a step but its cerainly not complete yet that it doent need monitering. Perhaps you tought i was talking of the robin. I should have made it more clear what i was refering to there.
 
  • #14
[b said:
Quote[/b] ]the California condor because you used it as a example that it had little chance of survibing without human intervention thats what this

Actually the part about the condors was a prepositional phrase, the 'this species' that I was refering to was the Ivory Woodpecker.

In other words.. If the same action isn't taken that has been taken to save the condors, the Ivory Woodpecker stands little chance of surviving.
 
  • #15
yup. sorry i went off on a rant im really irritable lately.
 
  • #16
hehe, np. I like debating.. tho I prefer it to not be over a misunderstanding or 2. I was just hoping that I wasn't rubbing you the wrong way.
 
  • #17
Wow I can't beleve I missed this until now (I mean since my original post). Anyway I would like to correct myself. There is a video somewhere online (I think audobon) but I have not seen it. I did hear what happened though. And it was published in last week's edition of Science
 
  • #18
there is... i posted it in one of the two threads.
 
  • #20
Saw the woodpecker thing on The Daily Show. The oak tree doesn't grow far from where.. the.. acorn fell before it.. grew.
 
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