New extralimital breeding records of saltmarsh sparrows () and Nelson's sparrows () and their implications.

Saltmarsh () and Nelson's () sparrows are sister taxa that breed in tidal marshes along the coast of the Northeastern United States and Canada. The Saltmarsh Sparrow breeds from mid-coast Maine south to Virginia, while the Acadian Nelson's Sparrow breeds from the Canadian maritime provinces south to northern Massachusetts. Here, we present three extralimital observations of breeding Saltmarsh ( = 2) and Nelson's ( = 1) sparrows.

Mercury exposure of tidal marsh songbirds in the northeastern United States and its association with nest survival.

The biogeochemistry of tidal marsh sediments facilitates the transformation of mercury (Hg) into the biologically available form methylmercury (MeHg), resulting in elevated Hg exposures to tidal marsh wildlife. Saltmarsh and Acadian Nelson's sparrows (Ammospiza caudacutua and A. nelsoni subvirgatus, respectively) exclusively inhabit tidal marshes, potentially experiencing elevated risk to Hg exposure, and have experienced range-wide population declines.

Framework for quantifying population responses to disturbance reveals that coastal birds are highly resilient to hurricanes.

Changes in the frequency and severity of extreme weather may introduce new threats to species that are already under stress from gradual habitat loss and climate change. We provide a probabilistic framework that quantifies potential threats by applying concepts from ecological resilience to single populations. Our approach uses computation to compare disturbance-impacted projections to a population's normal range of variation, quantifying the full range of potential impacts.

Factors that influence vital rates of Seaside and Saltmarsh sparrows in coastal New Jersey, USA.

As saltmarsh habitat continues to disappear, understanding the factors that influence saltmarsh breeding bird population dynamics is an important step for the conservation of these declining species. Using five years (2011 - 2015) of demographic data, we evaluated and compared Seaside () and Saltmarsh () sparrow apparent adult survival and nest survival at the Edwin B. Forsythe National Wildlife Refuge, New Jersey, USA.

Seasonal fecundity is not related to geographic position across a species' global range despite a central peak in abundance.

The range of a species is determined by the balance of its demographic rates across space. Population growth rates are widely hypothesized to be greatest at the geographic center of the species range, but indirect empirical support for this pattern using abundance as a proxy has been mixed, and demographic rates are rarely quantified on a large spatial scale. Therefore, the texture of how demographic rates of a species vary over its range remains an open question.