[Carpenter] Fw: elevations 3+1

[Frank Oberle]

All, Something to think about:
    Wow, I currently have been doing some Googling and research on the Greater Prairie Chicken and their the interdependency on elevation. I have gone back to some of the sites that I have seen
and photographed GPC, especially on their LEKS. To my amazement, most of those sights all have been over 1000 feet of elevation--more like 1030-50. Rather it be at Golden Prairie or the Root Prairie or up here in the Mystic COA.
   My yearning curiosity is how do these birds know where they can congregate and socialize
with other birds; sorta like where is the dance halls and the community centers. Yes we would all agree that these grassland birds need wide open spaces, but I believe they need certain
elevation areas in order to exist. Just maybe, if we are to have any vestige of hope in restoring
this poster bird of our ephemeral grasslands, there might be a need to protect some of these
very limited elevations in key areas.  We need data!!! Protecting their Social areas are just as important as their nesting sites.
      Another issue, but very limited due to my lack of ornithological expertise to make a worthy
comment, is this: If a Prairie Chicken is endowed with certain biological and instinctive traits that
enables the bird for survival, can we take GPC from an elevation, say 1250 feet, and expect them
to adapt to much less elevations--let's say 850 feet? This, I believe, is what we have done 
with the Wah'kon tah relocation initiative. I just really "feel" there is some correlation between
elevation, food, social gatherings and survival. Remember, I am just making some rank
and armature observations that probably has many holes in the bucket that I'm holding. Please read the following: 



 






Altimeters work by measuring altitude based on sea level, configuration. 
An altimeter does not actually measure altitude directly, but rather just atmospheric pressure. So an altimeter is actually a barometer created for a specific purpose. The altimeter uses the changes in atmospheric pressure to determine the changes in altitude. Why does pressure change with altitude? Simply put, the pressure at any given point in the atmosphere around the earth is a result of the weight of the atmosphere above it (pulled down by gravity). For this reason, the higher in the atmosphere you are, the less atmosphere you have above, and the less pressure exerted on you. 





To determine what else steered pigeons toward home, researchers conducted countless experiments, including snipping nerves in the nose. Once the nerves were severed, pigeons could not find their way home, leading scientists to assume the birds literally follow their nose. 

However, it's still unclear whether pigeons are always sniffing a course through the sky. They also have two internal magnetic "compasses," thought to be located near the nose and in the eyes, which may help them calculate the Earth's magnetic fields. 

Similar compasses, made of iron, have been found in the snouts of rainbow trout.  




Scientists have long noticed that birds feed intensely as air pressure falls. They apparently have an inborn barometer that is extraordinarily sensitive. This is a handy adaptation for all birds, even non-migrants, because storms usually are associated with falling pressure, and birds have a hard time getting food during a storm. The sooner they can predict a storm before it hits, the more time they have to prepare.

Scientists also have known for a long time that migrating birds fly at different altitudes than non-migrating birds, and maintain this altitude even on moon-less nights when they can't see the ground at all. How do they maintain a particular altitude? Many scientists suspect that this is also due to their ability to "feel" air pressure. Studies have proven that birds are extremely sensitive to small changes in air pressure, comparable to differences of only 5 to 10 meters in altitude. 

Recognizing air pressure is also handy because birds often migrate along frontal systems, and changing air pressure is one of the first signs that a front is coming. High pressure systems often have clear skies, which make using celestial navigation easier, and flying on high pressure days may even help "buoy" birds up a bit.

The Big Question
How do birds judge air pressure? Scientists don't know!! They do have a couple of guesses. One is that birds may be able to detect it through their inner ear. We detect large changes in air pressure in our own inner ear when we make a fast change in altitude--that's when our ears "pop." Another guess is that the birds detect air pressure somehow though the huge air sacs that connect to their lungs and fill much of the space inside their bodies. 


  
In histological and physicochemical examinations in collaboration with HASYLAB, the synchrotron laboratories based in Hamburg, Germany, iron-containing subcellular particles of maghemite and magnetite were found in sensory dendrites² of the skin lining the upper beak of homing pigeons.  This research project found that these dendrites are arranged in a complex three-dimensional pattern with different spatial orientation designed to analyze the three components of the magnetic field vector separately.  They react to the Earth's external magnetic field in a very sensitive and specific manner, thus acting as a three-axis magnetometer.

The study suggests that the birds sense the magnetic field independent of their motion and posture and thus can identify their geographical position.

The researchers further believe that this ability is not unique to homing pigeons as they expect that the 'pigeon-type receptor system . might turn out to be a universal feature of all birds'.  Equally, this concept might not only exclusively apply to birds, since it has been shown that many animals display behavior that is modified or controlled by the Earth's magnetic field.

The meaning of these minute iron oxide crystals goes farther than their amazing ability to help pigeons home.  Research into how they work has caught the interest of nanotechnologists concerning their potential application for accurate drug targeting and even as a data storage device.  The main problem, however, lies in their synthetic production.  According to Gerta Fleissner and her colleagues, "Even though birds have been producing these particles for millions of years, the main problem for scientists who want to find benefits from their use will be the technical production of these particles".

1. Fleissner et al (2007).  A novel concept of Fe-mineral-based magnetoreception: histological and physicochemical data from the upper beak of homing pigeons. Naturwissenschaften (DOI 10.1007/s00114-007-0236-0).

2. A dendrite is a branched extension a nerve cell (neuron)





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