New York Natural Heritage Program
Henslow's Sparrow
Ammodramus henslowii (Audubon, 1829)

Threats [-]
The most significant threat to Henslow's Sparrows is the loss of suitable grassland habitat. Economic factors have affected the viability of farms in New York. Many farmers have intensified their farming practices, converted hayfields to row crops, or abandoned farming altogether (Andrle and Carroll 1988, Post 2004, McGowan and Corwin 2008). Remaining hayfields are often mowed earlier and more frequently to increase production. As a result, the mortality rate of young in those fields is high and sometimes adults are killed during mowing. As farms are abandoned they are lost to development or the land reverts to shrublands and forests. Grasslands are becoming more scattered and isolated, reducing connectivity (Post 2004). Wetland loss is also a threat because this species often nests in nearby damp or wet meadows. As wetlands are drained for development any associated wet meadows are also lost (Andrle and Carroll 1988).

Conservation Strategies and Management Practices [-]
Identify public lands with Henslow's Sparrow populations where management may be more easily implemented. Develop education and outreach programs in areas where Henslow's Sparrows persist that are aimed at grassland management and preservation. Implementing a program in New York similar to the Conservation Reserve Program, would likely be beneficial to Henslow's Sparrow populations.

Research Needs [-]
The effects of certain farming practices on breeding populations should be evaluated. For instance, it would be beneficial to determine how different mowing frequencies and how different intensities of grazing affect Henslow's Sparrow populations. It would also be beneficial to know how mowing versus prescribed burning affects populations.