It's interesting to see that some populations which are nearly wiped out due to habitat changes, can adapt to the new conditions and slowly rebuild ... but it leaves questions like if the adaptation was behavioural or physical which allowed it's survival is the bird that survived tending to be its own sub species of what existed.
In Australia, well the north part of Queensland at the very least, since the 80s there's really not been that much funding or an obvious program of population monitoring of whatever native species remain, including birds.
I miss what used to be common bird calls from my youth even though I didn't know which bird species was responsible. I've resolved the mystery for a couple I could recall but one still eludes me. In my parts the high canopy tropical forests have taken a huge toll from the 90s, no real wet season with warm rain, no large storms, (these days it's not uncommon to hear alarm around a storm dropping 3 inches in a couple of hours ... used to have years where they were not uncommon,) a fungus pathogen taking out some trees which may just be down to the trees being stressed more than their evolution allowed for - oh yes, the fact that many summer storms on their westerly approach had started to hesitate on a direct track over the coastal areas might just boil down to the man made heat bubble with open cut coal mining and the large areas as per mining which now have no to little vegetation.
That's interesting in regard to remnant genes. The Black Robin is thought to have undergone repetitive genetic filtering from past events [1]
What I was thinking of was more along the lines where after a species faced extinction, what survived was due to slight genetic variance that in time the more successful would continue to push the more purposeful genes to adapt to the changes inflicted onto the area they inhabit or migrate more. I am of course not saying this is the instance in every population wipe out and re-emergence, I can point to instances where a simple change of behaviour comes down to learned behaviour, such as what happened with the introduction of cane toads and wildlife including birds learning how to eat the mongrels (carefully.)
The Paradise Parrot I would guess succumbed to the introduced rats ... and given their ground dwelling and termite nesting would have later faced the feral cat explosion. It is a pity.
I suspect in my immediate location only a couple of miles from a large forested area that was never heavily logged and now protected, that a small handful bird species remained unrecorded even if they were recognised by some common name by the immediate locals. The one bird species I'm still trying to identify had a simple call of individual loud chirps from high in octave to low and then half repeated from mid octave - it seems terribly unfamiliar to any one I've asked who I'd expect is familiar with all of the regions birds.
"... leading to speculation that the species has passed through several such population reductions in its evolutionary past, and has lost any alleles that could cause deleterious inbreeding effects"
Wow it was the darn mosquitoes. [1] Looks like they are working on that. [1] [2] I had always assumed island extinctions for bird populations the culprits were primarily introduced rats and snakes for times when sailing ships were the main form of travel; both rats and feral cats in more recent times.
Yes flightless birds were especially prone to cats and rats unless they were large enough not to be prey, or had a nesting strategy. It'd be a guess how many species went extinct before humans started to explore and migrate around the globe. In the last few hundred years only isolated populations on islands which had little defences against introduced predators are noted in the history books. By the late 19th century most of the damage was done with human exploration, either exploiting birds like the Dodo for food and oil, or introduction of something which changed the balance, though at times unintentional via a ship wreck.
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[ 0.25 ms ] story [ 61.7 ms ] threadIn Australia, well the north part of Queensland at the very least, since the 80s there's really not been that much funding or an obvious program of population monitoring of whatever native species remain, including birds.
I miss what used to be common bird calls from my youth even though I didn't know which bird species was responsible. I've resolved the mystery for a couple I could recall but one still eludes me. In my parts the high canopy tropical forests have taken a huge toll from the 90s, no real wet season with warm rain, no large storms, (these days it's not uncommon to hear alarm around a storm dropping 3 inches in a couple of hours ... used to have years where they were not uncommon,) a fungus pathogen taking out some trees which may just be down to the trees being stressed more than their evolution allowed for - oh yes, the fact that many summer storms on their westerly approach had started to hesitate on a direct track over the coastal areas might just boil down to the man made heat bubble with open cut coal mining and the large areas as per mining which now have no to little vegetation.
What I was thinking of was more along the lines where after a species faced extinction, what survived was due to slight genetic variance that in time the more successful would continue to push the more purposeful genes to adapt to the changes inflicted onto the area they inhabit or migrate more. I am of course not saying this is the instance in every population wipe out and re-emergence, I can point to instances where a simple change of behaviour comes down to learned behaviour, such as what happened with the introduction of cane toads and wildlife including birds learning how to eat the mongrels (carefully.)
The Paradise Parrot I would guess succumbed to the introduced rats ... and given their ground dwelling and termite nesting would have later faced the feral cat explosion. It is a pity.
I suspect in my immediate location only a couple of miles from a large forested area that was never heavily logged and now protected, that a small handful bird species remained unrecorded even if they were recognised by some common name by the immediate locals. The one bird species I'm still trying to identify had a simple call of individual loud chirps from high in octave to low and then half repeated from mid octave - it seems terribly unfamiliar to any one I've asked who I'd expect is familiar with all of the regions birds.
[1] https://en.wikipedia.org/wiki/Black_robin
"... leading to speculation that the species has passed through several such population reductions in its evolutionary past, and has lost any alleles that could cause deleterious inbreeding effects"
https://web.archive.org/web/20261004025452/https://birdshist...
https://thememorypalace.us/the-woods/
The red shock of feathers on the heads of the males,
the bright white that spilled down the sides of the long throat to pool in the center of the white wings,
hemmed in by borders that looked jet black in pictures,
but in real life were something other.
A glinting thing.
A blue-purple.
A night sky.
On the right night.
[1] https://economictimes.indiatimes.com/news/international/glob...
[2] https://greatergood.com/blogs/news/mosquitoes-in-hawaii (mosquito population reduction project )