The Migratory Highways of the Birds. (Based on a map by 

 Roger T. Peterson, National Audubon Society.) 



aside at Aransas, Texas, and in Wood Buffalo National Park in 

 Canada, for their winter and summer safety respectively. 



Meanwhile, however, the number of birds had sunk to a low 

 of only about twenty and grave doubts were entertained as to 

 whether all the effort was not too late. However, the great birds 

 continued to wing their way north and south each year, luckily 

 at such altitudes that they were for the most part out of range 

 of the free-firing gunmen, let alone the sportsmen. Considerable 

 propaganda also aided them by making country folk all along 

 their migration route aware of their existence, their times of 

 passing, and their plight. On the whole, man responded unusu- 

 ally well, so that very slowly the birds have made somewhat 

 of a comeback. Moreover, in 1959 they were for the first time 

 reported in eastern Montana, in Missouri, and in Illinois on their 

 way north. Nothing could be more encouraging to all those who 

 wish these birds to be saved from extinction. 



THE PASSING OF THE LESSER 



Migration is not a simple affair. Almost everybody has heard the 

 expression, but very few except trained biologists know precisely 

 what it means. The average person thinks of it as having some- 

 thing to do with birds flying back and forth in the spring or fall 

 from north to south or vice versa. This notion has more than just 

 a grain of truth, for true migration indeed means a regular sea- 

 sonal movement of animals from one place to another. However, 

 its range of variation in time, place, and extent is tremendous. 

 For instance, there is a bird, the Arctic Tern, that spends a part 

 of the year in the Arctic of the New World and another part in 

 the Antarctic south of Africa, and the rest of the year flying the 



eleven thousand miles from one to the other. Its route is first 

 across the North Atlantic, then all down the western coasts of 

 Europe and Africa, and thence over the stormy void of the 

 latitudes known as the "roaring forties" to the broken ice belt 

 of the southern polar regions. Most amazing is that the young 

 birds in their first year accomplish half of this virtually circum- 

 global expedition without outside assistance. On the other hand, 

 there are birds which migrate only from a wood where they 

 spend the winter to a neighboring field for the summer and then 

 back again. Nor are birds the only animals that migrate. Quite 

 the contrary, for it has now been discovered that a very large 

 number of all animals — ranging from worms to mammals — 

 make seasonal shifts in their place of residence. 



But birds are, of all migrators, the most superb and the 

 animals which are most readily seen thus engaged. Yet, although 

 many millions of them pass over the heads of most of us twice a 

 year, one could die at a ripe old age without ever knowing that 

 such a phenomenon took place. These great semiannual move- 

 ments for the most part follow set and invariable patterns; and 

 what is more, they proceed along regular airways like the best 

 commercial plane services. These are appropriately called 

 "flyways." 



In North America there are six of these (see map). This is the 

 over-all pattern, but it has now been discovered from close 

 observation over some fifteen years in the area we are presently 

 describing that there is a cross-continental side switch made by 

 many western birds that turn left into the Rio Grande valley on 

 their way south and so join the central stream. Thus we have 

 here a semiannual mixing of species from the east, central, and 

 western regions of the North American continent, which in 

 great part explains the enormous variety of birds seen in this 

 province. This fascinating aspect of nature is an integral part of 

 the scene on the coast of the East Chaparral Province, for there 

 is hardly a day in the year when one is not here reminded of 

 the endless passing of birds from far extremities of the earth 

 to the nearby arroyos or to the upper levels of the Mexican 

 mountains. Never a day passes here but one encounters some 

 new species of bird that simply was not there the day before — in 

 a roadside ditch, on a telephone wire, on the beach, or in a bush 

 behind the house — and they turn up in droves, not as lone 

 harbingers or lost sentinels. 



THE RETIRING ONES 



The mammals of the East Chaparral, like mammals everywhere, 

 are much more conservative, and they are much less often seen, 

 being for the most part nocturnal. There are the ubiquitous 

 raccoons and opossums, innumerable mice and rats, coyotes, 

 gray foxes, some otters, long-legged jack rabbits, and little cot- 

 tontails. But there is also the Peccary, the piglike ungulate of 

 tropical America that once, as we know by its bones found in 

 caves, existed as far north as New York. This is a shy one indeed, 

 venturing out into the open only at night. Then there are the 

 sun-loving reptiles and the temperature-controlled frogs and 

 other amphibians, the insects, and the perennial spiders and 

 snails. All seem to appear and disappear with pronounced sea- 

 sonal rhythm. 



The most notable and commonly seen mammal is the arma- 

 dillo of the so-called Nine-banded species (Tatusia novemcinctaj. 

 This always somehow seems to be a most unlikely citizen of 

 the United States, but it has always been present in south and 

 east Texas and has now spread east both on its own initiative 

 and with human assistance, not only to, but over, the Mississippi; 



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