Oak Titmouse
"The Oak Titmouse was once lumped with the very similar Juniper Titmouse as a single species, the aptly named Plain Titmouse. The two were split in 1996 based on distinct differences in their ranges and calls.
The Oak Titmouse is a small, nondescript, brownish-gray bird with a crest; its best field mark is its complete lack of distinctive field marks! This titmouse is a non-migratory species; it mates for life, and pairs defend year-round territories. They nest in tree cavities, but will also use nest boxes.
Unfortunately, these birds depend upon a habitat that has declined by up to 50% over the last century due to development for housing and agriculture. The fungal disease, sudden oak death, has also killed thousands of oaks in this habitat in recent years.
Since over 80% of oak woodlands in California are privately owned, education and cooperation between landowners and resource managers is a necessary part of Oak Titmouse conservation efforts."
Learn more and help ABC conserve this important habitat!
"Listen to a two-minute broadcast on this bird! "
Photo: Oak Titmouse by Bill Hubrick; Range Map, NatureServe
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Part 3 of Parenthood:
"There are other birds that dispense with every convention of home making and parenthood, and resort to cunning to raise their families. These are the "brood parasites," birds which never build their own nests and instead lays their eggs in the nest of another species, leaving those parents to care for its young.
The cuckoo is the best known brood parasite, an expert in the art of cruel deception. Its strategy involves stealth, surprise and speed. The mother removes one egg laid by the host mother, lays her own and flies off with the host egg in her bill. The whole process takes barely ten seconds. The parasitic cuckoo's egg is much larger than its victim's eggs
Cuckoos parasitize the nests of a large variety of bird species and carefully mimic the colour and pattern of their own eggs to match that of their hosts. Each female cuckoo specializes on one particular host species. How the cuckoo manages to lay eggs to imitate each host's eggs so accurately is one of nature's main mysteries.
Many bird species learn to recognize a cuckoo egg dumped in their own nest and either throw out the strange egg or desert the nest to start afresh. So the cuckoo constantly tries to improve its mimicry of its hosts' eggs, while the hosts try to find ways of detecting the parasitic egg.
One of the most extraordinary examples of deception is practiced by the screaming cowbird. This bird only dumps its eggs in the nests of bay-winged cowbirds. Unlike in any other known brood parasites, the screaming cowbird chicks are absolutely identical to the chicks of the host at the stage when they are dependent on the parents for food, Then, as soon as they fledge, they take on the plumage of their own species.
Another bird that gets away with great deception is the whydah, an African bird with a remarkably long tail. It dumps it's eggs into the nests of little finches. But the whydah chick does not evict its nest mates; instead it grows up with them.
The whydah chick looks completely different from the host nestlings. But when it opens its mouth, the resemblance is remarkable - the young whydah has a gape and mouth spots that closely mimic those of its nest mates. The hard-working parents see no difference in the row of open mouths and feeds them all equally.
The struggle between host and parasite is akin to an arms race, each trying to out-survive the other. But two birds take the struggle up to that old Cold War level MAD - mutually assured destruction. When the gnatcatcher realizes the cowbird has laid in its nest, it takes the extreme step of tearing the whole place apart, destroying it's and the intruder's eggs in the process. Then it starts all over again.
We hear much about manipulative youngsters in human society. But the young of some birds manage to manipulate their parents even before they leave the egg. The chicks of the American white pelican tell their parents when they are too hot or too cold by giving loud and clear distress calls from inside the eggs. This helps the parents incubate the eggs correctly; they respond to the calls by turning and re-settling on the egg.
The greater honeyguide in Kenya is another parasite. It lays its eggs in the nests of the red-throated bee-eater. But its chicks, when they hatch, have a deadly advantage. They are armed with a murderous hook-tipped bill.
The chicks of the red-throated bee-eater die under the vicious attacks of the honeyguide chick within the first few days of hatching. The murder weapon then drops off, its purpose achieved. The foster parents now devote all their energy towards feeding the killer of their own young. The black eagle, which nests on cliff ledges in Africa, is a species whose second chick is always doomed. It always lay 2 eggs. The chicks hatch about 3 days apart, so that the older chick is significantly larger than the younger one.
But no matter how abundant the food supply may be, the parents can only ever manage to raise one chick. The extra egg they lay is simply an insurance in case the first one is lost or fails to hatch. If both hatch successfully, the older sibling launches a relentless, killer attack upon the younger chick the moment it hatches.
Birds only behave brutally or with deceit because it works in terms of their own survival. But there are many examples of what we would recognize as "good" parenting. And are rosella parrots the bird world's perfect parents? Listen to how much they care. The eggs hatch over about five days, so at first there is a noticeable size difference between their chicks. You might expect the older ones to win.
But, unlike many other birds, these parrots are scrupulously fair in feeding. They make sure every nestling receives its proper ration. Sometimes the eldest will share its food with the youngest and weakest. The result of this consideration is a truly balanced family. After three weeks strength and weakness will have been ironed out and the nestlings are all the same size.
Perhaps the biggest and happiest of bird families are the Arabian babblers of Israel. These birds display an admirable family togetherness. They all play a part in feeding the baby birds.
Among white-winged choughs four adults are deployed to feed one young, because the beetle grubs they eat is so difficult to find. But they will also kidnap young from another family, enticing them away by spreading their wings like a toreador's cloak. The youngster is fed for the first season, then recruited into the feeding team in the next year. The result is a bigger "family", capable of raising more young.
In British Colombia the Barrows goldeneye also choose the extended family option. The female goldeneye will chase another female off the lake, but is happy to let the rival's abandoned offspring join her family. She may end up with 20 ducklings in tow, only half of them her own. This is not as altruistic as it seems. She does not have to feed them. And if a pike attacks, the odds are 2 to 1 against hers' being eaten.
In Australia, the magpie geese family is often headed by a male and two egg-laying females. When the time comes to conduct their young across a river to the lagoon where they feed, the three parents will snap at marauding crocs, a act of heroism that could easily lose them their heads.
Looked at as a whole, however, birds are not a lot more virtuous or dutiful in their home-making then humans. For example, it has long been thought that birds were the animal kingdom's best representatives of the romantic virtues. The courtship of birds, and their apparent togetherness, has inspired poets, songsmiths and advertising copywriters. We assumed birds don't cheat. Well, they do!"
From: http://www.pbs.org/lifeofbirds/home/index.html
See the last part of the Bird Parenthood series here next Winged Wednesday.
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On This Day: Disaster
Construction begins on deadly bonfire, Nov 16, 1999:
"Construction begins on a giant bonfire at Texas A&M University on this day in 1999, the continuation of a tradition that began 90 years earlier. Two days later, the bonfire collapsed, killing 12 students and injuring another 27.
For nearly a century, students in College Station, Texas, created a massive bonfire—self-proclaimed to be "the world's largest"—prior to their school's annual football game against their archrival, the University of Texas.
The beloved pre-game tradition had been canceled only once, in 1963 following the assassination of President John F. Kennedy. Over the years, the bonfire grew so big that its construction became an elaborate project requiring days of work by teams of student volunteers. On two previous occasions, the bonfire had partially collapsed; neither episode had been disastrous.
The 1999 bonfire was supposed to require more than 7,000 logs and the labor of up to 70 workers at a time. Just after dawn on November 18, students were working near the top of the 59-foot-high pile (4 feet higher than authorized) when, in the words of Jenny Callaway, a student who was on the stack, "It just snapped." Without warning, scores of students became caught in the huge log pile. Other students, including Caleb Hill who suffered only broken bones in his 50-foot fall, were lucky enough to fall away from the pile.
"People were running around calling people's names and crying," sophomore Michael Guerra said. "Other people were just like zombies. They couldn't believe what had happened." Cranes were immediately brought in to remove the logs and free the students but the process was painstaking, as any wrong movement could cause further collapse. The last survivor was pulled from the pile about six hours later.
The bonfire was cancelled for only the second time ever and an investigation began into the causes of the collapse. It was later determined that the first stack of logs did not have sufficient containment strength. The wiring used to tie the logs together was not strong enough for the job; the steel cables employed in prior years had not been used. The construction effort in general was also blamed, for creating "a complex and dangerous structure without adequate physical or engineering control."
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Oklahoma enters the Union, Nov 16, 1907:
"Indian Territory and Oklahoma Territory collectively enter the United States as Oklahoma, the 46th state.
Oklahoma, with a name derived from the Choctaw Indian words okla, meaning "people," and humma, meaning "red," has a history of human occupation dating back 15,000 years. The first Europeans to visit the region were Spanish explorers in the 16th century, and in the 18th century the Spanish and French struggled for control of the territory.
The United States acquired Oklahoma from France in 1803 as part of the Louisiana Purchase."
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Yesterday:
It was a comfortable 65° when I got up, so the cats were happy to go out on the screen porch. Thunderstorms and possible tornadoes were forecast to arrive at 3.00PM, so I let them back in at lunch time.
Ray wanted to work for a little while, and so we replaced my kitchen faucet. We removed the used temporary faucet that we had installed a while back. That meant taking everything out from under the sink, and being a contortionist with a basin wrench. The faucet company had sent the part to repair the original one, so we could put it back on the sink. Now that the faucet is installed, the handle still seems to be loose. I hope they sent us the right part.
The high was at noon, 81°, when we had a little sprinkling and the temperature started dropping into the 60's. There were no tornadoes in this area.
We are still at least 24" behind on rainfall, so it wasn't enough to do much for the drought when 1.61" of hard rain came through at 2.00PM yesterday.
1 comment:
Wow, you got a lot more rain than I did. The rain here only lasted a few minutes, but alway gratefull for any we get.
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