Priorities for Future Research

The lack of life history parameter estimates for the Puerto Rican Nightjar is one of the primary information gaps for the species. Information on nest, juvenile and adult survival is needed if demographic models are to be developed for the nightjar. Also, additional information on nesting biology and productivity is needed from other regions of the species' range. With the exception of a single nightjar nest in Maricao Forest (Delannoy 2005), information on nesting biology is limited to Guánica Forest (Kepler and Kepler 1973, Vilella 1995, Vilella 2008).

Detailed information on dispersal and spatial dynamics is required. Recent advances in radiotransmitter design and capture techniques for caprimulgids can be applied to the Puerto Rican Nightjar (Conway et al. 2007, Wilson and Watts 2008). Information on juvenile dispersal as well as movement dynamics of adult Puerto Rican Nightjars at multiple scales in the landscape is needed. This is particularly relevant given the apparent isolation of some nightjar populations (e.g., Susúa-Maricao) and the high degree of fragmentation of a large portion of privately owned lands occupied by nightjars (González 2010).

Additional research on nightjar-habitat relationships is warranted. Previous studies suggested the main limiting factor associated with use of habitat for nesting by nightjars was the presence of dense, tangled vegetation near the ground. Vilella (2008) illustrated relationships that could serve as the basis for future experimental work. For example, testing the effects on nightjar nest habitat use of experimentally manipulating the understory and midstory vegetation layers of forest stands at Guánica. Results obtained would generate new information on nightjar-habitat relationships and serve to further refine management alternatives for the species.

Finally, reintroducing the Puerto Rican Nightjar to the north-central region of the island should be strongly considered as a long-term conservation planing tool for the eventual recovery of the species. Like other parts of Puerto Rico, forest cover in this region has recovered greatly following the abandonment of agriculture. It currently encompasses a considerable area of mature secondary forest and is home to a vast diversity of flora and fauna (Lugo et al. 2001).  Reintroducing the Puerto Rican Nightjar to the moist karst forest region, where they have been absent for about a century, would entail a sequential approach involving: (1) multi-resolution habitat assessment, (2) selection of candidate sites, (3) demographic and genetic assessment of nightjar source populations, (4) development of capture, transport, and holding techniques for juvenile and adult nightjars, and (5) reintroduction and post-release monitoring. If this is ever pursued it would have multiple benefits, as the conservation value of moist karst forest occupied by nightjars would increase and the long-term viabilty of the species would be enhanced.