Streamside Bird Monitoring in Allegheny Portage Railroad National Historic Site

Tufted Titmouse (Baeolophus bicolor) - one of the most abundant bird species at Allegheny Portage Railroad National Historic Site point count stations. Photo © Bill Thompson.

A new report from the Eastern Rivers and Mountains Network summarizes the first 12 years (2007 to 2019) of monitoring the streamside bird community at Allegheny Portage Railroad National Historic Site. During that time period one observer conducted 372 point count surveys detecting 2,759 individual birds at 17 point count stations within the park.

Allegheny Portage Railroad National Historic Site contains a rich and diverse streamside bird community with a total 64 species detected; 58 of which are target species and presumed to be breeding in the park during summer months. The majority of the 20 most abundant species were forest-associated species including both forest-interior species and forest-generalist species but also a large number of species that thrive in human-modified (in this case suburban) landscapes with sufficient tree and shrub cover.

Fifteen species overall and six of the 20 most abundant species were of conservation importance in the Appalachian Mountains bird conservation region (Figure 1), highlighting the significance of even a relatively small park like Allegheny Portage Railroad National Historic Site to avian conservation. Most the species of conservation importance at the park were species dependent on intact, mature, deciduous forest as habitat for nesting and breeding.

Trends in abundance over the period of monitoring were assessed for the 58 species in the target population. Of those species, 40 (69%) appear to be stable or increasing and 18 (31%) appear to be declining during the period of monitoring.

Figure 1. Twenty most abundant streamside bird species at Allegheny Portage Railroad National Historic Site point count stations from 2007–2019. Bars represent the unadjusted mean birds per point (+1SD) across all years of monitoring. *Species of regional conservation importance.

The primary message from monitoring thus far appears to be that most species were stable or increasing in abundance at the park and were species associated with mature deciduous forest—the regional conservation priority.

This report provides the first information regarding long-term population trends of breeding birds in Allegheny Portage Railroad National Historic Site. Continued monitoring will provide new insights and future analyses will explore specific factors linked to population trends. As anthropogenic land use and climate change continue to reshape the Appalachian landscape, park managers will need this information to best allocate effort that aligns with regional conservation planning and other park priorities.

Report Citation:

Marshall, M. R. 2021. Streamside bird monitoring in the Eastern Rivers and Mountains Network: Allegheny Portage Railroad National Historic Site 2007–2019. Natural Resource Report NPS/ERMN/NRR—2021/2311. National Park Service, Fort Collins, Colorado. https://doi.org/10.36967/nrr-2287583.

For more information, contact the Eastern Rivers and Mountains Network Program Manager, Matt Marshall.