The primary objective of this program is to determine the population distribution and trends of Nightjar species across the United States. There is a general sense that populations of these species are declining. Information on the precise scale and magnitude of population changes are necessary in order to plot a course for conservation. However, prior to this program, there has been no widespread or long-term effort to monitor Nightjar populations. This effort is coordinated by the Center for Conservation Biology at the College of William and Mary and Virginia Commonwealth University. Nightjar surveys are standardized population counts conducted along roadside census routes at night. Each survey route consists of 10 roadside stops spaced 1-mile apart. Each route is surveyed only one time per year, but during a very specific survey window when Nightjars are typically most vocal. Success of this monitoring program is dependent on dedicated volunteers willing to conduct Nightjar surveys.
The initial sampling strategy was to conduct surveys along existing North American Breeding Bird Survey (BBS) routes in an effort to capture a broad volunteer base and replicate the BBS sampling locations. This approach allowed for rapid assessment that will guide future sampling design. Volunteers were also allowed to create their own standardized route in an effort to recruit volunteers who could place an additional survey route near an existing one did or for those not want to travel a long distance for a night-based survey. Data collected since 2007 has served as the foundation for a new “best effort” approach to stratify landscapes according to species distribution and habitat composition Participation is garnered by a larger group of citizen scientists than many other survey efforts because routes typically do not take more than two hours to complete, and the only experience necessary is a familiarity with 2-3 Nightjars species within their respective region. The protocol is self-explanatory, and all details (survey window, moonrise/sunset calendar, data sheets, etc.) are provided by the network coordinators, making it very easy for individuals to participate regardless of previous experience with surveys. The protocol uses six one-minute time blocks so that data may be compared with studies using shorter time periods.
As with any survey that relies on citizen scientists, there is the potential for inaccuracy. Statistical inferences with observer-created routes are limited, and locations of existing routes may limit detectability by under-sampling suitable Nightjar habitat, though this is being addressed with a new sampling approach. In addition, multi-regional analysis of standardized Nightjar data from the Northeast, Midwest, and US Nightar Survey programs (currently underway) should improve route placement in terms of volunteer retention and Nightjar detectability. Currently, there is not an online data entry option for participant.
Examples of use
Although it is nationwide in scope, the US Nightjar Survey Network has its strongest presence in the southwestern and southeastern United States. This protocol is also being implemented by partners in the Northeast US (Northeast Nightjar Survey) and several Midwestern states (Illinois, Wisconsin, and Michigan). Survey data has provided inferences to the response of Nightjars to varying composition of habitats within landscapes.
For more information
Abundance Protocols >