Willistown Conservation Trust Recommended Guidelines for Managing Grasslands to Promote Eastern Meadowlark Breeding Habitat

Natural History of Eastern Meadowlarks
Source: The Birds of Pennsylvania. McWilliams and Brauning. Cornell University Press. 2000.

In Southeastern Pennsylvania, Eastern Meadowlarks inhabit open fields and grasslands and breed in those that are relatively free of tree cover that may provide perches for predatory hawks. Generally, fields need to be over 20 acres for successful breeding. Although meadowlarks were common during the 1800’s and early 1900s, changes in agriculture, increased development and conversion of farm fields to woodlands have reduced their habitat. Since the 1960’s, meadowlarks have declined by up to 80%. There are very few known breeding sites in the Willistown area, and thus it is critical that these few sites be well managed to promote the breeding success of this species.

Eastern Meadowlarks may begin breeding in April and continue into July with unfledged young in late July. They rely on tall grasses for foraging and to protect their eggs and young from predators. They usually lay 3 to 5 eggs which are white and spotted with browns and purples, especially at the large end.

Mowing existing grasslands with breeding meadowlarks or with good potential for expansion of a breeding population

In the Willistown Area, we recommend mowing these fields at a height of 6 to 8 inches before April 15 if woody vegetation is present and then only mowing edges and paths if desired between then and the first week in August. Depending on the amount of weedy vegetation, you may mow the entire field after the first week in August. If weeds are not a significant problem, it may be best to leave the tall grasses for good winter habitat for many wildlife species.

The general objective of mowing is to keep woody and weedy vegetation from entering the grasslands. In some cases, it may be necessary to “spot mow” weed species during the summer, such as Canada thistle, oriental bittersweet and multiflora rose to ensure that these weeds do not spread. Care should be taken to avoid known nesting areas. It is best to spot mow these weed species just before they flower and at as low a height as possible.

A representative from Willistown Conservation Trust will be available to help you determine the appropriate management program for your meadowlark grassland. Call 610-353-2562 with any questions.