In the Trans-Fly north of Kiunga it is present in undisturbed seasonally flooded alluvial lowland forest (K. D. Bishop in litt. 1994, 1997, 1999, P. Gregory in litt. 1994, 1999, Richards and Rowland 1995, B. Whitney in litt. 2000). It may be found in altitudes up to 300 m (Beehler and Pratt 2016).

Tanysiptera hydrocharis has a limited range on the Aru Islands and a handful of localities in southern New Guinea (Papua, formerly Irian Jaya, Indonesia, and Papua New Guinea) to 300 m (Coates 1985, Beehler et al. 1986, Beehler and Pratt 2016). The species is considered rare and very poorly known, and was not recorded during recent surveys of the Aru Islands (Diamond and Bishop 1994, D. Gibbs in litt. per Beehler and Pratt 2016, K. D. Bishop in litt. 1994, 1997, 1999). There are recent records of small numbers of birds along the Elevala River north of Kiunga and recent records from Papua (see Clarke et al. 2010, Verbelen 2014, K. D. Bishop in litt. 1994, 1997, 1999, P. Gregory in litt. 1994, 1999, Richards and Rowland 1995) but it may occur throughout the Fly basin (B. Whitney in litt. 2000). There is also a recent record from the Torres Strait islands (Clarke et al. 2010) suggesting a wider distribution and a degree of dispersal.

Conservation Actions Underway
None is known.

Conservation Actions Proposed
Survey historical locations and potentially suitable habitats for the species on the Aru islands and in the Trans-Fly. Study its ecological requirements and threats.