“BirdTrack is organised by the BTO for the BTO, RSPB, BirdWatch Ireland, SOC and WOS.” (British Trust for Ornithology, etc.) is an online resource reporting sightings of birds in the UK and Republic of Ireland.
Bird numbers vary for a variety of reasons, particularly seasonally, this resource gives access to the reports. Accuracy relies on the consistency of the many humans watching.
The site on entrance shows the current data for a random choice of bird, headline here for the Skylark. This has a particular habit which changes visibility, open grassland ground breeding, secretive on the ground, plays predator attraction games when in the air. (to lead away from the nest)
Bird populations are often cited as weather and climate related, no doubt also strongly affected by the classic predator/prey natural cycle, the same for or because of food resources.
Posted by Tim
Tallbloke's Talkshop 
Why is it called twitching ?
JM: Not sure where this British idiom comes from. Observing twitchers bobbing their heads around to get the best view of a bird hopping around in a bush might be a clue. 🙂
Tallbloke look at the satellite.
http://www.accuweather.com/en/ca/national/satellite
Tallbloke clear that cosmic radiation reacts only to the activity of the magnetosphere. For now, avoids bursts of plasma from the Earth.
