‘On 11 February at the Bois Omar ibn el-Khattab (Forêt Moulay Abdellah/Forêt d’Agdal), I heard a warbler that sounded like an odd Yellow-browed Warbler Phylloscopus inornatus. It called for 5-10 seconds and went silent after that ; the calls were high pitched, a long >tsi-wee!<. The sound came from the walled section of the Parc Agdal des Eaux et Forêts so I could not see it.
The next day (Monday 12 February) I returned to the same place and after some wait the bird called, again from inside the walls of the Parc Agdal des Eaux et Fôrets (somewhere close to here: 33.995568, -6.840008). Even though the bird was not very close by, I managed to record a few calls and confirm it was not a Yellow-browed Warbler. Here are some of the calls, kindly edited for clarity by Magnus Robb’.
The Hume’s (Leaf-) Warbler Phylloscopus humei was formerly considered conspecific with P. inornatus, but it differs clearly in vocalizations and plumage, and co-exists sympatrically; there are some evidence that the two may occasionally hybridize.
The nominate race breeds in Russia (Altai, Sayan and S Baikal Ranges), in W & N Mongolia, in NE, E & SE Kazakhstan, in Kyrgyzstan, in NW China and Tien Shan S to NE Afghanistan and Kashmir, thence E through the Himalayas to S Bhutan and NE India (info from Clement, P. 2019. Hume’s Leaf-warbler (Phylloscopus humei). 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/58884 on 13 February 2019)
Il s’agit de la première mention au Maroc, en attente d’analyse par la CHM.