194 Henshaw on Causes affecting the Decrease of Birds. 



It is not necessary to enumerate the species that have been 

 noted among the birds thus destroyed or to institute any com- 

 parisons as to their relative or aggregate numbers. It is enough 

 to note here that the list when full}' made out will be found to 

 embrace all our smaller species whose routes of migration or 

 whose habitats are not so far inland as to place them beyond the 

 reach of the coast storms. That the larger species, too, are not 

 wholly exempt from disasters of this sort can be readily shown. 

 Hawks, Owls, Ducks, and even Pelicans having been forced by 

 gales against light-houses. The testimony is sufficient to show 

 that thousands of birds are annually destroyed in this way, and 

 that an infinitely greater number pass by unharmed and are lost 

 to sight in the obscurity of the gale. What then becomes of these 

 latter? 



It is perhaps not so well known that vessels coasting off shore 

 from ten to one hundred miles or more are frequently visited by 

 birds that have been swept off the land by the wind. I have 

 frequently during a voyage in the calm summer months found 

 in the early morning three, six, eight or a dozen or more land 

 birds perching on the vessel or flying in excited circles around 

 and over it. Some of these are doubtless forced away from land 

 by the pursuit of Hawks,* or by moderate off-shore breezes, and 

 without doubt soon find their way safely back. The same facts 

 hold good, I believe, for the coast line all over the world, and I 

 am told that in the Mediterranean it is extremely common for 

 birds to alight on vessels, and that here their flight is rarely 

 sufficiently protracted to in anywise injure them. But if caught 

 at any considerable distance from land, it is noticeable that these 

 wanderers will invariably die from exhaustion, no matter what 

 care be taken of them, showing conclusively that they must have 

 been on the wing a very long time. This fact is of interest, as 

 it seems to imply the utter impossibility of at least the weaker- 

 winged North American species — so many of which have been 

 detected in England and the Continent — crossing the ocean with- 

 out material assistance from vessels or other stable support upon 

 which to alight and rest. 



* In fact, I once saw a Falco polyagrus in attendance upon some Snowbirds and 

 Sparrows at a distance of about seven miles off the California coast, and similar ob- 

 servations have been made bv others. 



