Puerto Rico Sharp-Shinned Hawk

Puerto Rico Sharp-shinned Hawk (Eng.), Gaviln de Sierra, Falcn de Sierra (Sp.), Accipiter striatus venator (Sci.), Endemic, Puerto Rico.

Photo Father Alejandro Sanchez. Information compiled by Alan Mowbray, Interpretive Media Writer, EYNF/LEF

General Information

Accipiter striatus venator is an endemic subspecies of the North American Sharp-shinned Hawk, occurring only in Puerto Rico. This animal has been placed on the Federal endangered list because of its rapidly dwindling population on the island.

Description

The Puerto Rico Sharp-shinned Hawk is a small forest hawk, dark blue-slate gray above with rufous (reddish-orange) bars on its breast. Immature birds are brown above and streaked below. Its wings are broad and it has a proportionally long, squared-off tail, enabling it to turn and maneuver rapidly when chasing small birds. The Sharp-shinned Hawk male is typically 9.8 to 13 inches (25 to 34 centimeters) in length and weighs approximately 3.5 ounces (95 grams), while females are as much as 50 % larger, weighing 6 ounces (171 grams) or more. This characteristic, called sexual dimorphism, allows each sex to focus their predatory efforts on different sized prey.

Habits

Accipiter striatus venator feeds primarily on small birds ranging in size from Tanagers to hummingbirds. It requires a home range of approximately 370 acres (150 hectares). Females lay two (2) to three (3) white eggs in March or April and incubate them while the male searches for food. Average incubation period is approximately 32 days. Fledglings leave the nest 30 days after hatching.

Habitat

Restricted to five isolated mountain forest areas on the island. The sub-species suffered a 40 % decline in population by 1992. Subsequent deforestation due to road construction, installation of power lines and communications facilities have significantly reduced its habitat. Nest failures due to fledgling infestation with bot fly (Philornis deceptivus) larvae and nest predation by the Pearly-eyed Thrasher (Margarops fuscatus) have also contributed to its population reduction. Although an overall population of 129 birds has been reported on the island (Delannoy, 1992), in the El Yunque National Forest, the only two sharp-shinned hawks sighted (a solitary territorial pair) were detected in the south-central part of the forest, confined to the palo colorado forest.

Where to look for this animal in the EYNF

Very rarely, soaring above the Bao de Oro, or El Yunque nature trails.