A field-survey carried out in spring 2015 in Morocco confirmed the decline of the highly endangered and the only extant population of Great Bustard (Otis tarda) in Africa.
During the study Great Bustards were only seen at two of the seven leks (sites where displaying is taking place) occupied ten years ago. The total number of birds counted was 40-44, which represents a 40% decline over the last decade. The sex-ratio was still strongly female-biased (1 male: 3 females), but less than in previous surveys, which suggests that trophy hunting has not been the major mortality cause in recent times.
The productivity was 0.29-0.33 juveniles per female, the highest ever recorded in this population, suggesting that breeding success doesn’t represent the main problem for the survival of this population.
Adult mortality which was already identified a decade ago as the main factor causing the demographic decline is still a problem. But based on the recent development of the power line network at some areas, the main threat today is probably collision with these power lines (a decade ago, poaching was identified as the main threat for the population, followed by collision with power lines).
Urgent conservation measures are needed in order to prevent the extinction of this highly threatened population, and reducing the mortality caused by collision should, among other measures, be considered a high conservation priority.
The study results were published in this paper:
Alonso, J.C., Palacín, C., Onrubia, A., Aboulouafae, R., Amezian, M., El Idrissi Essougrati, A., El Khamlichi, R. & Noaman, M. 2016. Alarming decline and range reduction of the highly threatened Great Bustard Otis tarda in Morocco. Ostrich 87: 277–280.
Déclin alarmant de la Grande Outarde au Maroc
Une étude de terrain réalisée au printemps 2015 au Maroc a confirmé le déclin de la très menacée et la seule population existante de la Grande Outarde (Otis tarda) en Afrique.
Au cours de l’étude les Grandes Outardes n’ont été observées que sur deux des sept leks (sites où les outardes se concentrent pour l’accouplement) occupés il y a dix ans. Le nombre total d’oiseaux comptés était 40-44, ce qui représente un déclin de 40% au cours de la dernière décennie. Le sex-ratio était toujours fortement biaisé en faveur des femelles (1 mâle : 3 femelles), l’est toutefois moins que lors des études précédentes, ce qui suggère que la chasse aux trophées n’a pas été la cause la plus importante de mortalité ces dernières années.
La productivité, de 0.29-0.33 juvéniles par femelle, est la plus élevée jamais enregistrée pour cette population, suggérant que le succès de reproduction ne représente pas le problème majeur pour la survie de cette population.
La mortalité adulte qui a déjà été identifié il y a dix ans comme le principal facteur qui cause le déclin démographique est encore un problème. Cependant, sur la base du développement récent du réseau de lignes électriques dans certaines régions, la principale menace aujourd’hui est probablement la collision avec ces les lignes (une décennie plus tôt, le braconnage été identifié comme la principale menace pour la population, suivie par la collision avec les lignes électriques).
Des mesures de conservation urgentes sont nécessaires afin d’empêcher l’extinction de cette population très menacée, et la réduction de la mortalité causée par la collision devrait, entre autres mesures, être considérée comme une priorité absolue de conservation.
Les résultats de l’étude ont été publiés dans la revue Ostrich (voir l’article au-dessus de la première photo).
Hello,
A very interesting article. My name is Lars Schönberg and I am a volunteer from the “German Great Bustard Rescue Group” (Förderverein Großtrappenschutz e.V.) We have similar problems with power lines in Germany. The collision with them is one of the highest threats. We have more then 22 death bustards since 1990. Alone seven in 2013.
We spoke with the owner of these powerlines to mark them.
If you need more information, please contact me.
Best, Lars
Hi Lars,
Thanks for your interest and comment. Indeed collision with power lines is the main threat to the species now in Morocco, and we need to do a great work if we are going to save the species from extinction.
I noticed that you have written a nice summary about this study in your website: Alarmierende Nachrichten von Marokkos Großtrappen. Thank you for that.
I should note that this blog-post is the summary of a study (Alonso et al. 2016) that was carried out by a Morocco-Spanish team not just by Moroccans (you probably mean the blog?). I have added the PDF of the paper.
I noted your email, so I can contact you in the future if needed.
p.s.: I corrected the typo in your comment and also added the website link.
Best,
Mohamed
Good morning,
From Tangier in the north to the right bank of the lower Oued Ouergha in the south, the Great Bustard in Morocco has never been threatened either by collision with electric wires or by hunting. The main cause of its scarcity comes mainly from the change in agricultural practices in this region. The modernization of agriculture has replaced traditional agriculture, which previously provided it with habitat and favourite foods. The Cape Bustard also suffered the same fate and was extinct long before the Great Bustard for the same cause.