Waders and Hill-Goers
Geo- for grown-ups
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages    Log inLog in 
  GamesGames   

Waders and Hill-Goers

 
Post new topic   Reply to topic     Forum Index -> The Birds and the Bees
View previous topic :: View next topic  
Author Message
Jack Aubrey
Founder member


Joined: 31 Aug 2005
Posts: 513
Location: Camptoun, Scotland

PostPosted: Sun Mar 25, 2007 5:53 pm    Post subject: Waders and Hill-Goers Reply with quote

On the way along the Herring Road (or at least some of it - but that's another story Embarassed ) today we put up a series of plovers and dunlins and such-like. It caused me to reflect that birds which divide their time between the shore and the hills must do so on the basis of the tides.

But how do they know what time low tide will be?

Puzzled Jack
_________________
In the service of a Queen
Back to top
View user's profile Send private message AIM Address MSN Messenger
Haggis Hunter
Founder member


Joined: 29 Aug 2005
Posts: 2487
Location: The building site formally known as Edinburgh!

PostPosted: Sun Mar 25, 2007 6:18 pm    Post subject: Reply with quote

Not got a clue either, but perhaps they can sense the magnetic pull of the earth????? If that is how the tides actually work?
_________________
Let me know if I say anything that offends you
I might want to offend you again later Wink
Back to top
View user's profile Send private message Send e-mail
Wildlifewriter
Founder member


Joined: 04 Aug 2005
Posts: 948
Location: Norn Iron

PostPosted: Sun Mar 25, 2007 10:17 pm    Post subject: Reply with quote

If those plovers were of the golden type, my guess is that they are probably pairing up, looking for nesting sites, and generally getting it on - since it's coming up to that time of year.

Those Lammermuir Hills (sp?) are known as an important breeding site for waders, including golden plover, dunlin, curlew, and other like-minded articles.

-Wlw
Back to top
View user's profile Send private message Send e-mail
HighlandNick
Founder member


Joined: 30 Aug 2005
Posts: 635
Location: Highlands, Scotland

PostPosted: Mon Mar 26, 2007 6:22 pm    Post subject: Reply with quote

Clever birds...
They move around depending on a lot of factors, such as:
Availability of food
Weather
Tides
Seasons
Moon phases.....

Many migratory birds and homing pigeons have inbuilt compasses and also have been shown to navigate using the position of the sun. And salmon - their "noses" are very sensitive to "smelling" the water they were born in.

Now bees - there's an interesting subject - waggle dances........
Back to top
View user's profile Send private message
Tooey
Member


Joined: 24 Sep 2006
Posts: 129
Location: Strathspey

PostPosted: Fri Mar 30, 2007 5:25 pm    Post subject: Reply with quote

I saw an interesting program on TV (now that is something rare these days). They had attached micro cameras to homing pidgeons and taken them to France. They were able to demonstrate that the birds were following major road networks to find their way home.
Back to top
View user's profile Send private message Send e-mail MSN Messenger
Crazy Druid
Member


Joined: 25 Mar 2006
Posts: 188
Location: Edinburgh, Scotland

PostPosted: Sat Mar 31, 2007 9:14 am    Post subject: Reply with quote

Haggis Hunter wrote:
Not got a clue either, but perhaps they can sense the magnetic pull of the earth????? If that is how the tides actually work?


You are half right...

All the water on Earth is affected by two forces of nature:

1) The gravitational pull of the sun and moon, and
2) The force (centrifugal) the earth applies as it spins (29.79 km/s).

The Moon is 400 times closer to the earth than the Sun so its pull is a lot stronger..

What does the pull of the moon (and the Sun) do to the water?

It creates two types of tides, high and low!

As the moon rotates around Earth, tidal bulges occur.
The bulge is really a large wave beneath the moon that moves across the earth. On the opposite side of Earth, there is a second bulge.

These bulges are high tides. There are usually 2 high and 2 low tides occur each 24 hours and 50 minutes (the time it takes for the moon to orbit Earth)



But...

Then you have Spring Tides and Neap Tides...

Spring Tides And Neap Tides

When there is a full (or new) Moon ,the gravitational pull of the moon and sun are combined and at t these times, the high tides are very high and at low tide the tide is very low. This is known as a spring high tide.

During quarter phases the sun and moon cancel each other as they are at right angles, this causes a smaller differance between low and high tide. This is called a Neap Tide..work at right angles, causing the bulges to cancel each other.



Last edited by Crazy Druid on Sat Mar 31, 2007 3:16 pm; edited 1 time in total
Back to top
View user's profile Send private message Send e-mail MSN Messenger
Firth of Forth
Founder member


Joined: 29 Aug 2005
Posts: 1493
Location: East Lothian, Scotland

PostPosted: Sat Mar 31, 2007 9:20 am    Post subject: Reply with quote

Let's face it...these birds are clever creatures and have a variety of mechanisms to navigate with. If the conditions aren't right for using one, they have a backup system, or if they aren't sure about where they are, the can check using another system. Of course, sometimes they make errors or all systems fail and they end up completely off course. Sound familiar?

I can remember having to write an essay at University about bird navigation for the animal behaviour module - it was fascinating stuff. But I think a lot more is known now compared to 30 years ago when I had a go at the essay!
_________________
Utterly smitten by a Captain
And now Mrs Aubrey
Back to top
View user's profile Send private message Send e-mail
Crazy Druid
Member


Joined: 25 Mar 2006
Posts: 188
Location: Edinburgh, Scotland

PostPosted: Sat Mar 31, 2007 9:42 am    Post subject: Reply with quote

Yep they are very clever, take the homing pigeons they can use the sun and the stars to take navagational bearings and they have some sort of in built compass...but once they have flown the route a few times...they follow the roads Laughing Its true..research has tracked them flying round a roundabout and taking the correct exit....Even turning at junctions

My uncle used to have loads of Pigeons and he spent many days telling me how clever his birds were and to see them come home after flying hundreds of miles was fascinating.

Some researchers even say that some diurnal birds fly AA-suggested routes Shocked even if it means the journey they fly is longer...

So I wonder if the saying "as the crow flies" is a lot more complex than the strait line that we are used to thinking Question Question
Back to top
View user's profile Send private message Send e-mail MSN Messenger
arock&ahardplace
Member


Joined: 08 Sep 2006
Posts: 184
Location: Edinburgh

PostPosted: Mon Apr 02, 2007 6:01 am    Post subject: Reply with quote

Thanks for posting that bit about the tides, CD. I didn't know all of that. And your animations made it much more clearer.
_________________
Remember: no matter where you go, there you are.
Back to top
View user's profile Send private message

Display posts from previous:   
Post new topic   Reply to topic     Forum Index -> The Birds and the Bees All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Create your own free forum now!
Terms of Service Purchase Ad Removal Forum Archive Report Abuse