Background
Louisiana Waterthrush populations are usually not easy to monitor during peak breeding season of most other songbirds. They show up earlier (as early as the 3rd week of March), nest earlier (as early as late April with most nests with eggs reported from May 7 to June 3), and become quiet and difficult to find after breeding. They are among the first Warblers to leave the state (as early as the 3rd or 4th week of July). Also, they tend to forage and nest in narrow stream and river corridors within large expanses (greater than 800 acres) of forest habitat.

Louisiana Waterthrush are very sensitive to pollution and forest disturbance, because the aquatic insects that make up a major portion of the of the Waterthrush's diet are heavily influenced by water-quality. They make good indicator species of the general condition of headwater streams, and they can indicate the quality of the uplands that feed water into the stream channel.

Goal
We would like to make a concerted effort to sample the presence and density of Louisiana Waterthrush along the stream corridors in the Important Bird Areas of Pennsylvania, which could be missed by other sampling methods.

Methods
Basic Survey
We are asking volunteers to walk along stream and river corridors, and other appropriate water areas between May 5th and July 7th to survey breeding territories of Louisiana Waterthrush males. Number of males (mostly singing) detected along each Kilometer of stream habitat surveyed will be recorded to provide an estimate of this breeding density.

Estimating Stream Length
Stream length will be estimated by one of three methods.

1. 1. Use mapped landmarks as starting and ending points of survey so the distance traveled can be estimated from published maps. These landmarks could include bridges and roads crossing streams, parking areas, trails, and areas where at least two waterways (mapped streams, creeks or rivers) meet.
2. 2. Use a GPS (Global Positioning System) unit to record start point, distance traveled, and end point.
3. 3. Count paces and estimate the number of meters covered (divide by 1000 to find number of Km).

General information
We are not looking for nest locations but if breeding status information (use breeding status codes from mini-atlas) will be recorded where appropriate. Louisiana Waterthrushes and Northern Waterthrushes may be found together and when they are not singing, they can be easily misidentified. The Sibley guide points out subtle differences between the two Waterthrush species. For example, the Louisiana Waterthrush tends to be larger with larger bills. They usually have buffy rear flanks, brighter pink legs, fewer and browner breast streaks, and a bold white supercillium. Great care should be taken when identifying these very similar species.