24 LOCALITIES FOR COLLECTING. 
In this book I have endeavoured to name with each species 
of bird some definite locality where they may be found, which 
is rather necessary, as certainly on the Spanish side of the 
Straits birds are very locally distributed, more so than in 
most countries I have seen. It is difficult to surmise the 
cause of this, as precisely similar tracts of country within no 
very great distance of each other are not always frequented 
by the same birds. On the Spanish side, without doubt, the 
most common bird as regards numbers is the Goldfinch 
[Carduelis elegans), and the most universally distributed the 
Stonechat. The number of birds of prey is very great, 
chiefly feeding on rabbits, rats, mice, reptiles, and insects ; 
they are very useful, and as the ground-breeding birds suffer 
much in the nesting-season from snakes and lizards, those 
birds of prey which feed mostly on these enemies of the 
smaller birds render their lessei feathered brethren valuable 
protection. The number of small birds, especially duiing the 
season of migration, is sure to be noticed even by the most 
unobservant. Immense quantities of Larks, Finches, and 
even some of the Warblers are brought into the markets ; 
but as a Spaniard seldom shoots at such small fry, they are 
chiefly netted, caught at night with a lantern and bell, or 
snared with bird-lime {Uga) . 
The best localities for an ornithologist living at Gibraltar 
to obtain specimens or watch migration is the country west 
of an imaginary line drawn due north from Gibraltar as far 
as the latitude of Seville. Within this district, part of which 
is given in the Map attached to this volume, as much can be 
done as is possible in three or four months^ time ; and the 
district is large enough to require three or four years to work 
it out thoroughly. 
In the immediate vicinity of Gibraltar (or el Penon, as the 
Spaniards call it) , the cork- wood of Almoraima and the level 
ground, mud-flats, and old salinas " between the rivers " on 
the way to Algeciraz ofler to the collector capital ground 
for work. In the cork-wood particularly, several birds are 
found breeding which do not seem to nest elsewhere. The 
ground north-east of Gibraltar is to a great extent covered 
