These are adults. Formerly widespread in East Asia, this endangered species now has the most restricted range of any spoonbill. At its low point, the world population was down to just over 200 birds, but it now appears stable at about 1600 adults. It is rare in Japan, so we were fortunate to see these bird. They are similar to Eurasian Spoonbill, but average smaller. Their black facial skin encompasses a wider area between the eye and the bill as seen here. Canon PowerShot SX60
References:
BirdLife International 2017. Platalea minor. The IUCN Red List of Threatened Species 2017: e.T22697568A119347801. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T22697568A119347801.en. Downloaded on 09 May 2019.
Matheu, E., del Hoyo, J. & Kirwan, G.M. (2019). Black-faced Spoonbill (Platalea minor). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52780 on 9 May 2019).