In Europe, only a few cases have been detected in wild birds since April 1, at the height of the migration north.
Mid-May is the height of spring migration, and there is a whole birding subculture in the city, with hundreds of people draped in field glasses roaming the Ramble's paths in the early morning, sizing each other up by the relative immensity of their binoculars.
The current nationalist zeitgeist took hold in 2015, when the parliamentary election campaign coincided with the height of the migration crisis convulsing Europe.
The assailant may also have reached Paris faster and more easily than expected because asylum seekers were rushed across some national borders at the height of the migration crisis in Europe this year to avoid bottlenecks after Hungary closed its borders, ironically to keep out suspected militants.
That was Sept. 15, at the height of the southward migration of broad-winged hawks, when a vast flock of the birds, called a kettle, passed by the mountain.
This year's event — timed as always to coincide with the height of the spring migration — will include individual competitors from Israel, Belgium and Britain, according to Sheila Lego, marketing director for New Jersey Audubon, the organizer.
Gull Point covers 319 acre, of which 67 acre form the Natural Area and are closed to park visitors during the height of the bird migrations.
It would be a mistake for the UK referendum on continued membership of the European Union to be held this summer at the height of an expected EU migration crisis, Italy's former prime minister Enrico Letta has said.
A more intriguing inquiry was the dynamics that sustained migration during the height of the conflict in 2014.
For a comparison using the usual definition, the measured values were transformed to the sand flux using the simple relation Q ∝ H × V, where Q is the sand flux, H is the height of the bedform, and V is the migration speed.
