Hi Everybody!!
A frequent question I get is: When do I take the feeder down so the birds leave? It does not matter what You (or any human) does, it has nothing to do with the birds. If You take your feeder down, they will leave your location, but not necessarily start on the migration trip to Mexico. They go when they determine it is time to go! One group did leave here on the night of the 21 (Sept). Tonight, we will look at what the Equinox has to do with the migration in the Wikipedia excerpt (and link) below. Once again, You will find the photostudies in the G+ Albums at the links below. September 24 and 25. Enjoy!

The new albums are uploaded to G+ and ready for viewing (unlocked!). The links are below to each photostudy. Sorry some of You are having problems with the slideshows. Keep trying!

You will see more birds came in for these albums. I am preparing You now: this will be the last week of Migration Photos because they will be gone!
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link 1:

https://plus.google.com/u/0/photos/117645114459863049265/albums/5931152611113291761

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link2:
https://plus.google.com/u/0/photos/117645114459863049265/albums/5931154910410671697

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link 3

https://plus.google.com/u/0/photos/117645114459863049265/albums/5931158651799920193

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link 4:

https://plus.google.com/u/0/photos/117645114459863049265/albums/5931159961598161793

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link 4:

https://plus.google.com/u/0/photos/117645114459863049265/albums/5931163083224852097

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link 5:
https://plus.google.com/u/0/photos/117645114459863049265/albums/5931165208938178657

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link:6
https://plus.google.com/u/0/photos/117645114459863049265/albums/5931166976370795569

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link 7:
https://plus.google.com/u/0/photos/117645114459863049265/albums/5931168533181843041

FAT is where its at!

https://en.wikipedia.org/wiki/Equinox

Equinox

From Wikipedia, the free encyclopedia

An equinox occurs twice a year (around 20 March and 22 September), when the plane of the Earth's equator passes the center of the Sun. At this time thetilt of the Earth's axis is inclined neither away from nor towards the Sun. The term equinox can also be used in a broader sense, meaning the date when such a passage happens. The name "equinox" is derived from the Latin aequus(equal) and nox (night), because around the equinox, night and day are about equal length.

At an equinox the Sun is at one of two opposite points on the celestial spherewhere the celestial equator (i.e. declination 0) and ecliptic intersect. These points of intersection are called equinoctial points: classically, the vernal point (RA = 00^h 00^m 00^s and longitude = 0º) and the autumnal point(RA = 12^h 00^m 00^s and longitude = 180º). By extension, the term equinox may denote an equinoctial point.

The equinoxes are the only times when the subsolar point (the place on the Earth's surface where the center of the Sun is exactly overhead) is on the Equator. The subsolar point crosses the Equator moving northward at the March equinox and moving southward at the September equinox. (Since the sun's ecliptic latitude isn't exactly zero it is not exactly above the equator at the moment of the equinox, but the two events usually occur less than 30 seconds apart.)

The equinoxes are the only times when the terminatoris perpendicular to the Earth's Equator. Thus the Northern and Southern hemispheres are illuminated equally. (At the solstices, that angle reaches its minimum of 66.5°, corresponding to 90° minus Earth's axial tilt).^[2]

Another meaning of equinox is the date when day and night are the same length.^[3] The equinox is not exactly the same as the day when day and night are of equal length for two reasons. Firstly, because of the size of the sun, the top of the disk rises above the horizon (constituting 'sunrise' which is the start of 'daytime') when the center of the disk is still below the horizon. Secondly, the Earth's atmosphere refracts sunlight which means that an observer can experience light (daytime) even before the first glimpse of the sun's disk has risen above the horizon. To avoid this ambiguity the term equilux is sometimes used in this sense.^[4]^{[note 1]} Times of sunset and sunrise vary with an observer's location (longitude and latitude), so the dates when day and night are of exactly equal length likewise depend on location. For places near the equator the daytime is always longer than the night, so they would never experience an equinox by this definition.

UT date and time of equinoxes and solstices on Earth^[1]
event	Northward equinox		Northern solstice		Southward equinox		Southern solstice
month	March		June		September		December
year
year	day	time	day	time	day	time	day	time
2010	20	17:32	21	11:28	23	03:09	21	23:38
2011	20	23:21	21	17:16	23	09:04	22	05:30
2012	20	05:14	20	23:09	22	14:49	21	11:12
2013	20	11:02	21	05:04	22	20:44	21	17:11
2014	20	16:57	21	10:51	23	02:29	21	23:03
2015	20	22:45	21	16:38	23	08:20	22	04:48
2016	20	04:30	20	22:34	22	14:21	21	10:44
2017	20	10:28	21	04:24	22	20:02	21	16:28
2018	20	16:15	21	10:07	23	01:54	21	22:23
2019	20	21:58	21	15:54	23	07:50	22	04:19
2020	20	03:50	20	21:44	22	13:31	21	10:02

During an equinox, the Earth is not tilted toward or away from the Sun and the length of the day is the same at all points on the Earth's surface.

Date

When Julius Caesar established his calendar in 45 BC he set March 25 as the spring equinox. Since a Julian year (365.25 days) is slightly longer than an actual year the calendar drifted with respect to the equinox, such that the equinox was occurring on about 21 March in AD 300 and by AD 1500 it had reached 11 March.

This drift induced Pope Gregory XIII to create a modern Gregorian calendar. The Pope wanted to restore the edicts concerning thedate of Easter of the Council of Nicaea of AD 325. (Incidentally, the date of Easter itself is fixed by an approximation of lunar cycles used in the Hebraic calendar, but according to the historian Bede the English name "Easter" comes from a pagan celebration by the Germanic tribes of the vernal (spring) equinox.) So the shift in the date of the equinox that occurred between the 4th and the 16th centuries was annulled with the Gregorian calendar, but nothing was done for the first four centuries of the Julian calendar. The days of 29 February of the years AD 100, AD 200, AD 300, and the day created by the irregular application of leap years between theassassination of Caesar and the decree of Augustus re-arranging the calendar in AD 8, remained in effect. This moved the equinox four days earlier than in Caesar's time.

Names

Northward equinox and southward equinox: names referring to the apparent motion of the Sun at the times of the equinox. The least culturally biased terms.
March equinox and September equinox: a usage to avoid Northern Hemisphere bias (implied by assuming that March is in the springtime and September is autumnal – true for those in the Northern Hemisphere but exactly opposite in the Southern Hemisphere).
Vernal equinox and autumnal equinox: these classical names are direct derivatives of Latin (ver = spring and autumnus =autumn). Again, this is from a hemisphere-specific perspective of spring and fall.
Spring equinox and fall equinox or autumn equinox: these more colloquial names are again from a hemisphere-specific perspective of spring and fall.
Vernal point and autumnal point are the points on the celestial sphere where the Sun is located on the vernal equinox andautumnal equinox respectively (again, the seasonal attribution depends on the hemisphere).
First point (or cusp) of Aries and first point of Libra are names formerly used by astronomers and now used by navigators andastrologers. Navigational ephemeris tables record the geographic position of the First Point of Aries as the reference for position of navigational stars. Due to the precession of the equinoxes, the astrological signs of the tropical zodiac where these equinoxes are located no longer correspond with the actual constellations once ascribed to them. The equinoxes are currently in the constellations of Pisces and Virgo. In sidereal astrology (notably Hindu astrology), by contrast, the first point of Aries remains aligned with Ras Hammel "the head of the ram", i.e. the Aries constellation.

Length of equinoctial day and night

On the day of the equinox, the center of the Sun spends a roughly equal amount of time above and below the horizon at every location on the Earth, so night and day are about the same length. The word equinox derives from the Latin words aequus (equal) and nox (night). In reality, the day is longer than the night at an equinox. Day is usually defined as the period when sunlight reaches the ground in the absence of local obstacles. From the Earth, the Sun appears as a disc rather than a point of light, so when the center of the Sun is below the horizon, its upper edge is visible. Furthermore, the atmosphere refracts light, so even when the upperlimb of the Sun is 0.4 degree below the horizon, its rays curve over the horizon to the ground. In sunrise/sunset tables, the assumed semidiameter (apparent radius) of the Sun is 16 minutes of arc and the atmospheric refraction is assumed to be 34 minutes of arc. Their combination means that when the upper limb of Sun is on the visible horizon, its center is 50 minutes of arc below the geometric horizon, which is the intersection with the celestial sphere of a horizontal plane through the eye of the observer. These effects make the day about 14 minutes longer than the night at the Equator and longer still towards the Poles. The real equality of day and night only happens in places far enough from the Equator to have a seasonal difference in day length of at least 7 minutes, actually occurring a few days towards the winter side of each equinox.

https://en.wikipedia.org/wiki/September_equinox#Human_culture

September equinox

From Wikipedia, the free encyclopedia

The Southward equinox (or September equinox) is the moment when the sun appears to cross the celestial equator, heading southward. Due to differences between the calendar year and the tropical year, the Southward equinox can occur at any time from the 22nd to the 24th day of September. At the equinox, the sun rises directly in the east and sets directly in the west. Before the Southward equinox, the sun rises and sets more and more to the north, and afterwards, it rises and sets more and more to the south.

In the Northern Hemisphere the Southward equinox is known as theautumnal equinox. In the Southern Hemisphere it is known as the vernalor spring equinox.

Thanks to G+ Awesome Auto Backup for creating the following highlight clips from these albums:

Getting Fat is where its at!!!!!!!
https://en.wikipedia.org/wiki/Hummingbird

Metabolism[edit]

With the exception of insects, hummingbirds while in flight have the highest metabolismof all animals, a necessity in order to support the rapid beating of their wings. Their heart rate can reach as high as 1,260 beats per minute, a rate once measured in a Blue-throated Hummingbird.^[17] They also consume more than their own weight in nectar each day, and to do so they must visit hundreds of flowers daily. Hummingbirds are continuously hours away from starving to death and are able to store just enough energy to survive overnight.^[18]

Hummingbirds are capable of slowing down their metabolism at night or at any other time food is not readily available. They enter a hibernation-like state known as torpor. During torpor, the heart rate and rate of breathing are both slowed dramatically (the heart rate to roughly 50 to 180 beats per minute), reducing the need for food.

The dynamic range of metabolic rates in hummingbirds^[19] requires a corresponding dynamic range in kidney function.^[20] The glomerulus is a cluster of capillaries in thenephrons of the kidney that removes certain substances from the blood, like a filtration mechanism. The rate at which blood is processed is called the glomerular filtration rate (GFR). Most often these fluids are reabsorbed by the kidneys. During torpor, to prevent dehydration, the GFR slows, preserving necessities for the body such as glucose, water and salts. GFR also slows when a bird is undergoing water deprivation. The interruption of GFR is a survival and physiological mechanism unique to hummingbirds.^[20]

Studies of hummingbirds' metabolisms are highly relevant to the question of how amigrating Ruby-throated Hummingbird can cross 800 km (500 mi) of the Gulf of Mexicoon a nonstop flight. This hummingbird, like other birds preparing to migrate, stores up fat to serve as fuel, thereby augmenting its weight by as much as 100 percent and hence increasing the bird's potential flying time.^[21]