32 BULLETIN 326, U. S. DEPARTMENT OF AGRICULTURE. 



Remains of small birds in two stomachs amounted to 1.88 per cent. One stom- 

 ach contained portions of a Porto Paean grosbeak (Loxigilla portoricensis) and 

 another a small black feather only ; there is evidently some basis for the fear 

 shown these hawks. House mice (Mus musculus) were found in eight stomachs 

 and formed 5.59 per cent. They were noted in stomachs taken in March, April, 

 and May only. The only real criticism of this small hawk is its large consump- 

 tion of, lizards, amounting to 40.4 per cent of its entire food. One ameiva 

 ( Ameiva exul) was taken, but the great mass was made up of the ever-abundant 

 anolis, of which four species were definitely identified (Anolis cristatellus, A. 

 gundlachi, A. krugi, and A. pulchellus) . Unless of small size, they were usually 

 pulled in two before being swallowed. Miscellaneous animal matter composed 

 largely of spiders amounted to 2.26 per cent. 



Under present conditions the sparrow hawk must be considered a valuable 

 species, as it feeds so largely on the changa or mole cricket. Although many 

 lizards, whose food is entirely insects, are taken, their numbers are so great 

 that no impression is made upon them. 



The number of mice eaten illustrates to what extent these rodents have over- 

 run the island. The sparrow hawk is not large enough to attack rats, except, 

 perhaps, young animals. To encourage the birds about cane fields occasional 

 high perches from which they can watch for prey should be provided along the 

 fences. Their numbers should increase in the lowland region, as their natural 

 food is abundant and easily obtained. 



PIGEON HAWK. Falco columbarius columbarius Linnaeus. 

 Gavilan. 



The pigeon hawk is a rare winter visitant to Porto Rico. Sundevall (1869, 

 p. 601) received a single specimen from Hjalmarson, of Arecibo. Gundlach 

 (1878, p. 162) saw one at the Laguna de Guanica and secured a female at Que- 

 bradillas. Stahl (1883, p. 136) had specimens in his collection, and Richmond 

 (MS.) notes that a small hawk seen at the Hacienda Catalina, in March, 1900, 

 may have been of this species. None were seen by me. It is fortunate that this 

 little falcon is not more common, as it is one of the few species found that are 

 injurious, its food being made up largely of small birds. 



DUCK HAWK. Falco peregrinus anatum Bonaparte. 

 Gabilan, Halcon de Patos. 



Gundlach (1878, p. 161) notes seeing a duck hawk repeatedly at the Laguna 

 de Guanica in November, 1873, where it was feeding on ducks and coots. 

 Stahl (1883, pp. 58, 136) found this species about the lagoons and had a female 

 from Porto Rico in his collection. It is apparently a rare winter visitant, fol- 

 lowing the migrating water birds, and while not abundant enough to be of much 

 damage should not be protected. Its food is almost entirely birds of various 

 species. 



BROAD-WINGED HAWK. Buteo platypterus platypterus (Vieillot). 

 Guaraguou de Sabana. 



The broad-winged hawk was formerly a common resident, mainly in the 

 interior, according to Gundlach (1878, p. 160), who secured specimens. Rich- 

 mond (MS.) saw one near Utuado April 6, 1900, and identified it certainly. 

 This is the only recent record for the bird. Stahl (1883, p. 58) undoubtedly 

 erroneously considered it a migrant. Gundlach (loc. cit.) reports its food as 

 small reptiles, large insects, and birds. I did not see this hawk during my 

 stay on the island and it is very rare at present. 



