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THE FORUM
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20-Apr-23, 07:55:34 AM
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23761
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Rochester Falcons / Falcon Watches / Re: Twitter
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on: 30-Jan-10, 04:57:54 PM
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WanderingFalcon (Carol P.): 1/30/10 - It's 1degree above 0! Snow flurries falling. Cloudy. Brrrr! Will go out a little later to find Falcons. Everybody keep warm. 23 in Maryland and the snow is begining!  Yuk! Bring it on Girl!!! I'm waiting. Could you send some here please? (I better be careful what I wish for). Donna - You can have it ALL, my friend!  |
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23763
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Other Nature Related Information / Raptor Web Cams / Re: Blackwater Eagles are back
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on: 30-Jan-10, 04:46:57 PM
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Both Cams just went black....snow problems interfering with wireless.
Snow problems!  I'll say!! The weather people were wrong again - currently at 6 or 7 inches and still falling. 1-3 were predicted by me last night (Cambridge is right across the Bay).  And were not gonna get any snow!!!! Pffft. |
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23768
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Support / Camera Problems / Re: Cam #1
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on: 30-Jan-10, 10:32:33 AM
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Technical problems, logistical problems, and the weather are delaying work on this problem. It could take a week.
Hopefully it's only a wet cable connector from the blowing snow. The signal from the camera could come back when the connection dries out.
Oh well....we wait. Thanks. |
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23769
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Other Nature Related Information / General Nature Discussion / Male great tits with brighter breasts
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on: 30-Jan-10, 09:17:29 AM
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January 29, 2010
Male great tits with brighter breasts have stronger sperm, according to the first study to find a link between flashiness and sperm strength. The birds' vibrant plumage appears to act like a flashing billboard, broadcasting the males' reproductive superiority to females eager to produce offspring.
The advertisement likely finds an appreciative audience in female great tits, since snagging a male with high-quality sperm isn't exactly a lark.
That's in part because free radicals threaten sperm cells in many animals, including humans. Created by cells when stressed by pollution and other factors, free radicals are groups of oxygen-activated atoms that can damage sperm cells, weakening their swimming ability.
Many animals' bodies produce antioxidants that fight free radicals—including male great tits. The birds have an antioxidant called carotenoid that not only defends against free radicals but also gives their breast feathers a yellow hue.
The new research shows that in males with more carotenoid, and thus more color, the sperm is better able to withstand a free radical onslaught—and females seem to know it.
Though human males don't display ornate natural plumage, the bird research has some parallels to people, said study leader Fabrice Helfenstein, an evolutionary ecologist at the University of Bern in Switzerland.
For instance, free radicals are thought to be a major cause of infertility in people.
Likewise, some studies have shown that men with more attractive faces have better quality semen.
Male Massage
To investigate whether more colorful great tits have more resilient sperm, Helfenstein and colleagues increased the parenting "workload" of 29 nesting pairs in Bern, Switzerland, in 2008. Such added stress is known to boost free radicals.
Two days after a great tit mother and father—which share parenting duties—hatched their brood, the team added an additional two baby birds per nest.
The scientists also observed a control group of 31 nests that were left undisturbed.
At 7 and 15 days after the broods hatched, the scientists trapped both the stressed and nonstressed males and massaged their cloacas—all-purpose openings found in many animals—to make the males ejaculate.
Under the microscope, the scientists observed how fast and robustly the birds' sperm moved. Unlike human sperm, which make fanciful loops and twirls, bird sperm swim "very straight," Helfenstein added as an aside.
The results showed that among nonstressed males, sperm robustness was about equal.
Among the stressed males, though, great tits with paler plumage had more listless sperm than colorful males—suggesting that having more carotenoid helps cope with stress.
But in samples taken on day 15, the paler birds' sperm quality was only slightly reduced by stress. This means that even pale great tits can eventually compensate when times get tough, according to the recent study in the journal Ecology Letters.
In a further step, the team also force-fed males on two separate occasions with carotenoid-laced maggots. The control group was given placebo maggots.
This "vitamin supplement" improved the drabber males' sperm quality—strengthening the link between carotenoids and sperm strength, Helfenstein said.
Cheaters
The findings also give some insight into why female great tits cheat, Helfenstein added.
Because "females cannot always get the [colorful] males they want," he said, the females will often settle for a less flashy mate.
But the females will still sneak off for a rendezvous with a better-looking male—and a dose of better sperm.
Overall, the study has begun to unravel the century-long mystery of why males often boast brazen colors, even though it makes the birds more conspicuous to predators, Helfenstein said.
"It adds a bit of understanding to this puzzle."
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23771
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Other Nature Related Information / General Nature Discussion / Amazon kingfisher makes rare U.S. appearance (TX)
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on: 30-Jan-10, 09:06:50 AM
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LAREDO – News spreads fast in the birding community.
On Sunday afternoon, two birders from Canada overnighting in Laredo on their way to the Rio Grande Valley visited Zacate Creek, a popular birding site in Laredo. There, they spotted and photographed a female Amazon kingfisher, a species of bird never previously confirmed in the United States.
One, Alan Wormington of Leamington, Canada, "immediately posted it from his hotel room [Sunday] night," said local birder Tom Miller. "Already, people drove up [Monday] morning."
So far, birders from at least eight states and two Canadian provinces have arrived in Laredo to catch a glimpse of the rare kingfisher.
The Amazon kingfisher is typically found no farther north than southern Tamaulipas state in Mexico, birders said.
Its appearance coincides with a recent sighting of the bare-throated tiger heron in the Rio Grande Valley. That bird has already attracted many birders to South Texas. Now, many of those are making stops in Laredo.
Although several photographers took photos of the bird, it must be confirmed with the American Birding Association before the sighting can be considered official.
This is not the first time there have been possible sightings of an Amazon kingfisher in South Texas, but this is the first time the bird has been photographed for confirmation.
No males, or even a second female, have been spotted. Although no one knows for sure where the bird came from, one theory is that, as the recent cold front moved south, instead of staying in front of it, she may have tried to go around it, ending up north of the Rio Grande in the process, according to Miller.
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23773
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Rochester Falcons / Falcon Watches / Re: Twitter
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on: 30-Jan-10, 08:51:42 AM
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WanderingFalcon (Carol P.): 1/30/10 - It's 1degree above 0! Snow flurries falling. Cloudy. Brrrr! Will go out a little later to find Falcons. Everybody keep warm. 23 in Maryland and the snow is begining! Yuk! (I better be careful what I wish for). |
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off with his ....... uh you get the idea
