BIRDS OF PORTO RICO. 5 



brush-filled pastures, and areas given over to small crops. Twenty- 

 six of these species, comprising 252 individuals, belonged to benefi- 

 cial forms of economic importance, and the remainder, 139 indi- 

 viduals of 9 species, were neutral forms, harmless, and inoffensive. 

 Near Lares, in the interior, a census taken on June 28 covered 

 an area of approximately the same size, but one of coffee plantations 

 and small farms. Here 335 individuals of 27 species were seen; of 

 these, 21 species (300 individuals) were beneficial and 6 species (35 

 individuals) were neutral. These results compare very favorably 

 with censuses taken on similar cultivated areas in eastern United 

 States during the breeding season. The relative importance of birds 

 to the major agricultural interests of the island may best be under- 

 stood by a consideration of species commonly found in cane fields, 

 coffee plantations, and citrus groves. 



BIEDS FOUND IN CANE FIELDS. 



Cane fields cover the larger part of the arable lowlands of the 

 island and in favorable localities extend over the foothills and 

 higher slopes. As these fields are cultivated intensively and offer 

 no safe nesting sites unless bordered by palms or other trees, they 

 are used only as feeding grounds by birds coming in from near by 

 where cover and security are to be found. The fields are frequented 

 chiefly when being plowed or cultivated, as grubs, mole crickets, and 

 other insects are then readily accessible to the birds. When the 

 cane grows higher, birds are seen in the roads, which cut the fields 

 into squares, and in the dense tangle of stalks some species find con- 

 venient shelter. No bird harms the cane in any way, and those that 

 are not directly beneficial by destroying insects, and to a less extent 

 weed seeds, are neutral and do no damage. During most of the year, 

 only adult insects of the important pests are available, immature 

 forms being exposed mainly at plowing time. To see a flock of 

 blackbirds at that season following closely in the furrows behind 

 the plow, eating greedily and carrying food to their young, empha- 

 sizes their value. Following is a list of birds found regularly in 

 the cane fields; a number that occur more or less casually are not 

 included : 



Martinete (Butorides v. cubanus) . 

 Garza {Florida c. ccernlescens) . 

 Falcon (Falco s. loquacula). 

 Rolita (Chcemepelia p. trochila) . 

 T6rtola (Zenaida z. lucida) . 

 Judfo (Crotophaga ani). 

 Zumbador (Anthracothoraoe aurulentus) . 

 Pitirre (Tyrannus d. dominicensis) . 

 Golondrina (Petrochelidon f. pceciloma). 



Golondrina (Progne dominicensis). 

 Ruiseilor (Mim-us p. orpheus). 

 Pizpita dorada (Seiurus aurocapillus) . 

 Reinita (Cosreba portoricensis) . 

 Veterano (Arnandava melpoda). 

 Mariquita (Agclaius xanthomus) . 

 Mozambique (Holoquiscalus brachypterus) , 

 Chamorro bicolor (Tiaris b. omissa) . 

 Gorrion (Tiaris o. bryanti). 



The same species frequent tobacco fields and areas of small farms, 

 where legumes, maize, and other small crops are grown. 



