Cornell eBird currently uses Helopsaltes ochotensis for Middendorff's Grasshopper Warbler. Locustella ochotensis, used in the pool and the BirdForum account, is an earlier genus combination.
It is brown above, with a pale eyebrow and belly, faint streaking on the crown and back, and a rufous tone on the rump and upper tail.
It uses damp grassland, thickets, and forest glades, including tall grass around marshes and lakes. It searches the undergrowth for insects.
An extinction-risk assessment has not been added yet.