Spring raptor migration at Jbel Moussa in 2017 (report)

By | 26 November 2017

Census of vultures and other raptors in the 2017 prenuptial migration on the southern shore of the Strait of Gibraltar, Jbel Moussa – Morocco

During the spring migration of 2017 at Jbel Moussa, and depending on the prevailing weather conditions and in particular with moderate westerlies, the census was carried out during 64 days from 18 February until 10 September (see under Rüppell’s Vulture why this late date is included with ‘spring migration’). During that period, a little over 40,000 birds belonging to 20 raptor species were recorded.

Apart from the most abundant migrants, some of the species counted are national or regional (Western Palearctic) rarities. Here are the highlights of the season:

White-backed Vulture (Gyps africanus): 1 bird in May (second record for Morocco and 7th for Western Palearctic).

Rüppell’s Vulture (Gyps rueppelli): 24 birds between February and September (15 birds in spring 2016). Two observations were particularly noteworthy; the first is of a first-year juvenile observed on 6 and 24 June (photo below). The majority of birds reaching Morocco and the Iberian Peninsula are immature birds whereas juveniles (as well as adults) are extremely rare. (For example out of 44 birds with positive age determination recorded in Spain in the period 2011-14, only three were juvenile (7%), see: Rodríguez & Elorriaga 2016. Identifcation of Rüppell’s Vulture and White-backed Vulture and vagrancy in the WP. Dutch Birding 38: 349-375). And the second observation is of an immature bird still migrating northwards with Griffon Vultures on 9 September. This is why this date is counted with spring migration (and also why this passage should be termed ‘northbound’ or ‘northward migration’, because in many cases it’s neither ‘spring’ nor ‘prenuptial’).

Griffon Vulture (Gyps fulvus): The passage of this species took place from late February to early September with a peak in the first half of May. During that period almost 6000 vultures were counted. Although comparison with different years is not possible, but for reference some 2.658 birds were counted in spring 2016. An immature bird was found in a very weak condition, it was treated and wing-tagged (M17, see photo).

Cinereous Vulture (Aegypius monachus): 4 birds observed between February and May (6 birds in spring 2016).

Lesser Spotted Eagle (Clanga pomarina): 2 birds seen in May and June.

Steppe Eagle (Aquila nipalensis): 1 immature bird seen on 18 May (first record for Morocco).

Spanish Imperial Eagle (Aquila adalberti): 1 immature bird seen on 20 March.

As in the previous seasons, several people contributed to the census. The author of the report, Rachid El Khamlichi, thanks everyone and also thanks GREPOM (BirdLife partner in Morocco) for the financial support during this season. See the report below.

Recensement des vautours et autres rapaces en migration prénuptiale 2017 sur la partie sud du détroit de Gibraltar, Jbel Moussa – Maroc

Du 18 février au 10 septembre 2017, la partie sud du Détroit de Gibraltar, et en particulier le Jbel Moussa et ses environs, a connu un important passage d’oiseaux planeurs appartenant à différentes espèces dont plusieurs rares au Maroc comme le Vautour africain (Gyps africanus), le Vautour de Rüppel (Gyps rueppelli), le Vautour moine (Aegypius monachus), l’Aigle Ibérique (Aquila adalberti), l’Aigle pomarin (Clanga pomarina) et pour la première fois un Aigle des steppes (Aquila nipalensis). Des Vautours fauves munis de marques alaires en Espagne et au Portugal et des Vautours percnoptères bagués en France et Espagne ont également été observés.

Durant plus 64 jours, en fonction des conditions météorologiques dominantes et en particulier avec des vents d’ouest modérés, nous avons recensé le passage d’un peu plus de 40.000 oiseaux appartenant à 20 espèces, dont 5.999 Vautours fauves (2.658 recensés pendant la compagne prénuptiale 2016). Voir le rapport ci-dessous.

Censo prenupcial 2017 de Buitres y otras rapaces en migración por el área sur del Estrecho de Gibraltar, Jbel Moussa – Marruecos

Entre el 18 de Febrero y el 10 de Septiembre 2017, el área sur del Estrecho de Gibraltar y concretamente el Jbel Moussa y su entorno, ha conocido un importante paso de aves planeadoras pertenecientes a varias especies, entre ellas especies consideradas raras en Marruecos, como el Buitre dorsiblanco africano (Gyps africanus), el Buitre moteado (Gyps rueppelli), el Buitre negro (Aegypius monachus), el Águila imperial ibérica (Aquila adalberti), el Águila pomerana (Clanga pomarina) y por primera vez una Águila esteparia (Aquila nipalensis). Se han observado también Buitres marcados con marcas alares procedentes de España y Portugal y Alimoches anillados de Francia y España.

Según las condiciones meteorológicas dominantes y en especial con vientos de poniente moderados y durante más de 64 días, se ha censado el paso prenupcial de más de 40.000 aves pertenecientes a 20 especies, de ellos 5.999 Buitres leonados frente a 2.658 censados en la campaña prenupcial del 2016.

Report (PDF):

El Khamlichi, R. 2017. Censo prenupcial 2017 de Buitres y otras rapaces en migración por el área sur del Estrecho de Gibraltar, Jbel Moussa – Marruecos. Recensement des Vautours et autres rapaces en migration prénuptiale 2017 sur la partie sud du détroit de Gibraltar, Jbel Moussa – Maroc. Go-South Bulletin 14: 219-229.

Rüppell’s Vulture (Gyps rueppelli) observed at Jbel Moussa, northern Morocco on 6 and 24 June 2017

Rüppell’s Vulture (Gyps rueppelli) observed at Jbel Moussa on 6 and 24 June 2017 (Rachid El Khamlichi).

Griffon Vulture (Gyps fulvus) wing-tagged at Jbel Moussa after its recovery, 18 August 2017

Griffon Vulture (Gyps fulvus) wing-tagged at Jbel Moussa after its recovery, 18 August 2017 (Rachid El Khamlichi)