Endemic critically endangered Puerto Rican nightjar more widespread than thought

November 2009. A new study of the Critically Endangered Puerto Rican nightjar Caprimulgus noctitherus suggests that the species' geographic range is greater than previously estimated. This is the major finding of Geographic distribution of the Puerto Rican Nightjar: A patch occupancy approach, a joint effort between the Sociedad Ornitológica Puertorriqueña, Inc. (SOPI, the BirdLife Partner and Species Guardian for Puerto Rican Nightjar), Mississippi State University, USGS Cooperative Research Units, BirdLife International, and The British Birdwatching Fair.

With an estimated population of 1,400-2,000 individuals, Puerto Rican Nightjar is a single-island endemic species found in coastal dry and lower montane forests in the south-west of Puerto Rico. Fragmentation, loss and degradation of its habitat, especially from residential, industrial and recreational expansion are the main threats. SOPI, as part of the BirdLife Preventing Extinctions programme, liaised with researchers, Dr. Francisco Vilella and graduate student Rafael González to carry out the first systematic presence-absence survey to improve current knowledge on habitat and distribution of the nightjar.

Larger range than previously thought
Puerto Rican Nightjar was recorded over a broad region of southern Puerto Rico. "Based on our results and location information obtained over the last few years it appears the geographic range of the species may be considerably different from what had been previously estimated", said Dr Francisco Vilella, USGS Research Scientist and Professor of Wildlife Ecology at Mississippi State University. The study results suggest that the species' range outside protected areas could be considerably greater than the approximately 4,583 ha (47% of total range) reported by earlier studies.

Deforestation & urban sprawl threats
However, unprotected areas in Puerto Rico are experiencing increasing deforestation from urban and suburban development. "Sites where Puerto Rican Nightjar presence was detected in the south-central regions of the island were characterised by a high degree of habitat disturbance, and included small, isolated forest fragments frequently surrounded by pastures or housing development", emphasized Rafael González, Graduate Research Assistant. Rafael continues "Forest clearing was ongoing in the vicinity of several of the easternmost sites as we were conducting our surveys."

"It is an urgent conservation need to acquire habitat, work with private landowners, government agencies and other NGOs to ensure the continuity and integrity of the nightjar's habitat", said Verónica Méndez, Conservation Coordinator from SOPI.

One clear implication of the results is that several sites in the south-central and south-east region of the island where nightjar presence was detected have not been incorporated in any of the major conservation planning efforts for Puerto Rico. "We recommend nightjar occupied sites in the south-central and south-eastern portions of the species' range should be assessed for their conservation potential", concluded Dr. Vilella.

SOPI is now developing the Species Action Plan with the Puerto Rican Nightjar Network to establish action points for the conservation of the species.

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