Population ecology of the Arabuko Sokoke Scopes Owl

Ivon Constanza Cuadros Casanova, Camilo Zamora and Katharina Lameter, master students of the Technical University Munich, spent several months (April-October 2016) in the Arabuko Sokoke Forest to study the population ecology and behaviour of the Arabuko Sokoke Scopes Owl Otus ireneae (see pictures below). First studies conducted by Munir Virani indicated that this bird species has a restricted home range and very specific habitat demands, strongly related to Cynometra woodland (see picture below).DSC_0509The two master students assessed various data: (i) Complete presence/absence  assessment based on play back calls; (ii) Detailed vegetation assesment and habitat structures at sites occupied/un-occupied by O. ireneae; (iii) Telemetry studies including males, females and juveniles to analyse home range sizes, movement activities and habitat preference (see picture below, one individual with a transmitter); (iii) Collection of pellets (see picture below) under occupied roosting trees to determine the consistence of the species´ diet; (iv) Poaching activities (wood and bush meat) by assessing logging  camps all over the study region, which is assumed to negatively affects the habitat quality and thus species persitence of O. ireneae. The two candidates will analyse and publish their data in the next step. (Pictures by Ivon Constanza Cuadros Casanova and Camilo Zamora).

Based on their collected telemetry data, presence-absence-analyses, and detailed data on habitat structures they found that Otus ireneae occurs spatially restricted in dense Cynometry woodland, where tall, old Cynometra trees are available. The students are going to publish their work very soon – together with  the local collaborators. Unfortunatelly, the Arabuko Sokoke Forest is under severe environmental pressure, due to various reasons: (i) climate change (with subsequent negative effect on food security, which increases the pressure on the forest for alternative income – from wood and game), (ii) illegal usage of forest ressources like wood and bush meat (see pictures below), (iii) very high demograhic pressure (need of land), (iv) very high densities of elephants inside of the forest (which are fenced to prevent human wildlife conflicts). Find some impressions below (pictures taken by Ivon Constanza Cuadros Casanova and Camilo Zamora).