The written form occurs in Capell's Index 'Weraeria : see Juwalarai'; but the listing for Juwalarai D27 (Capell's D26) does not have any further information.
Tindale writes 'Because of a blunder by Fraser (1892) it has been confused ... with Ualarai D27 of the Narran River (1974:200).
Wafer and Lissarrague present arguments for and against including similar forms as related to either the Darling Tributaries language (Gamilaraay D23 etc) or the Central NSW language (Wiradjuri D10 etc) (2018:215-223). There is very little information about this name and the existing sources do not agree as to its identity, nor are there any references to the name in Mura.
Speaker numbers were measured differently across the censuses and various other sources listed in AUSTLANG. You are encouraged to refer to the sources.
Speaker numbers for ‘NILS 2004’ and ‘2005 estimate’ come from 'Table F.3: Numbers of speakers of Australian Indigenous languages (various surveys)' in 'Appendix F NILS endangerment and absolute number results' in McConvell, Marmion and McNicol 2005, pages 198-230 (PDF, 2.5MB).