Hi, Good to see the reports of Louisiana Waterthrushes coming in from southern Ohio. They are among our earliest Warbler family (parulidae). We expect them to return to northern Ohio around April 1, and have established territories soon after regardless of weather. Given their preference for high quality running water as nesting habitat, the Louisiana Waterthush can establish territory even though there may be snow, and the still waters preferred by the Northern Waterthrush are still frozen over. The shores of lake Erie are along the northern edge of the breeding range for the Louisiana Waterthush, so expecting migrants in non running water habitat later than the third week in April is not very realistic. Given the very similar and sometimes overlapping morphology of the 2 species, any Waterthush species found along still waters on dates after about April 20 in Northern Ohio can very safely assumed to be Northern Waterthush unless extraordinary observation proves otherwise. While there are a few nesting sites along streams and creeks in NW Ohio, Louisiana Waterthush are far more common nesters in the eastern part of the state where the hills of the Allegheny plateau create their preferred habitat. Haans ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. Please consider joining our Society, at www.ohiobirds.org/site/membership.php. Our thanks to Miami University for hosting this mailing list. You can join or leave the list, or change your options, at: listserv.miamioh.edu/scripts/wa.exe?LIST=OHIO-BIRDS Send questions or comments about the list to: [log in to unmask]