Distribution and breeding ecology of the Ferruginous Duck (Aythya nyroca) in Algeria

Djelailia, A., Baaziz, N., Samraoui, F., Alfarhan, A. H. & Samraoui, B. (2017). Distribution and breeding ecology of the Ferruginous Duck Aythya nyroca in Algeria. Ostrich 0(0) DOI: 10.2989/00306525.2017.1313331
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Abstract:

We conducted a survey of the distribution of Ferruginous Duck Aythya nyroca across Algeria and analysed the influence of nest-site characteristics on nesting success at a Ramsar site, Lake Tonga. The species was found to occupy different wetlands (freshwater lakes, brackish marshes and salt lakes) across three major climatic belts (subhumid coastal strip, semi-arid Hauts Plateaux and arid Sahara). Mean clutch size of successful nests was 13.3 ± 6.0 eggs (N = 26) with a hatching rate of 74% for successful clutches. Nesting success was recorded for 44% of nests with clutch desertion (72.7%) accounting for the majority of failed clutches. Egg size of the study population, which breeds at the southern limit of the species’ range, was significantly smaller than that of its northerly counterparts. Clutch size was negatively related to egg size and positively associated with depth of water below the nest, suggesting that older, more experienced or high-quality birds monopolised the safest sites. Successful clutches were significantly associated with tall vegetation, suggesting that when nesting is carried out mainly on offshore floating islets, protection against aerial predators and heat stress determine nesting outcome. Conspecific brood parasitism was significantly and positively associated with deferred egg-laying and smaller egg size, suggesting an age-dependent mechanism.

Distribution et reproduction du Fuligule nyroca Aythya nyroca en Algérie

Nous avons mené une enquête sur la distribution du Fuligule nyroca Aythya nyroca à travers l’Algérie en analysant l’influence des caractéristiques des sites de nidification sur le succès de la nidification au sein d’un site classé Ramsar: le Lac Tonga. L’espèce occupe différentes zones humides (lacs d’eau douce, marais d’eau saumâtre et lacs salés) à travers trois zones climatiques majeures (bande côtière subhumide, Hauts Plateaux semi-arides et Sahara). La grandeur de ponte moyenne est de 10,0 ± 2,96 œufs (N = 29 pontes) avec un taux d’éclosion de 74,7% pour les pontes réussies. Le taux de réussite a totalisé 44% des nids, avec une prédominance d’abandons des pontes causant l’échec de la reproduction (82%). La taille des œufs de la population étudiée est plus petite que celle des populations se reproduisant à des latitudes plus élevées. La grandeur de ponte est négativement associée à la taille des œufs et elle est positivement liée au niveau de l’eau: ceci suggère que les individus plus âgés, ayant plus d’expérience, ou ceux de meilleure qualité monopolisent les sites les plus sûrs. Les pontes réussies sont significativement associées à une végétation haute, suggérant que pour les nids construits sur des îlots flottants, une protection contre les prédateurs aériens et l’exposition au soleil, conditionne le succès de la nidification. Le parasitisme intra-spécifique a été positivement associé à une ponte tardive et à des dimensions réduites des œufs, suggérant un mécanisme dépendant de l’âge.

Ferruginous Duck (Aythya nyroca). Photo: Francis C. Franklin / CC-BY-SA, Wikipedia

Ferruginous Duck (Aythya nyroca). Photo: Francis C. Franklin / CC-BY-SA, Wikipedia

Nesting ecology of Ferruginous Duck (Aythya nyroca) in north-eastern Algeria

Fouzari, A., Samraoui, F., Alfarhan, A. H. & Samraoui, B. (2015). Nesting ecology of Ferruginous Duck Aythya nyroca in north-eastern Algeria. African Zoology 50: 299–305. doi: 10.1080/15627020.2015.1108165
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Abstract:

The status of waterbirds breeding in protected areas in North Africa needs constant monitoring because of a naturally fluctuating environment and permissive attitudes towards illegal activities likely to negatively affect population dynamics of threatened species. We present the results of a study conducted at a protected site, Lake Tonga, north-eastern Algeria, on a breeding population of Ferruginous Duck Aythya nyroca, a Near-Threatened duck subjected to considerable pressure from egg-pilfering and illegal hunting. Two distinct habitats within the lake were used by Ferruginous Duck: an Alder carr (Alnus glutinosa) and floating islets across the lake. The mean clutch size was 9.51±1.84 eggs (N = 51 clutches) with hatching rate of 80.7% for successful clutches. Breeding success was low (37%) with predation (33%) and clutch desertion (17%) accounting for the majority of failed nests. The probabilities of nest failure and nest desertion increased with a delayed onset of egg laying. Predation was not significantly associated with egg laying date and vegetation cover, but late breeders nesting in dense vegetation seemed to suffer less predation. Conspecific brood parasitism was positively associated with nest size, whereas interspecific brood parasitism was marginally associated with water depth. We discuss different hypotheses concerning nest desertion, and argue that illegal hunting and disturbance may best explain why birds desert their nests.

Ferruginous Duck (Aythya nyroca)

Ferruginous Duck Aythya nyroca (photo: Tony Smith, in flickr CC BY)

 

Results of the eighth winter waterbird census in Libya in January 2012

Etayeb, K. S., Berbash, A., Bashimam, W., Bouzainen, M., Galidana, A., Saied, M., Yahia, J. & Bourass, E. (2015). Results of the eighth winter waterbird census in Libya in January 2012. Biodiversity Journal 6(1): 253–262.
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Abstract:

After sporadic observations and reports on Libyan birds during the last century, a regular census of wintering birds at Libyan coastal wetlands started in January 2005. Results of each winter census till 2011 have been published. The survey of 2012 was carried out by the authors of the present paper. The general aim was to continue the census of wintering waterbirds in Libya, despite the difficulties that faced the team after the War of Liberation, and the fact that certain areas, very important for birds, have been declared military areas. A total of 29,314 individuals belonging to 69 waterbird species was counted. Comparatively, the number of sites covered in 2012 was less than that in previous years of the survey. The majority of individuals counted belong to seven gull species. This survey also observed a total of 56 individuals of Aythya nyroca Guldenstadt, 1770, a Near Threatened species, as well as, for the first time, a single individual of Canada Goose Branta canadensis (Linnaeus, 1758) in eastern Libya.

Eco-ethology of the wintering Ferruginous Duck (Aythya nyroca) in Garaet Hadj Tahar, Northeast of Algeria

Merzoug, S. E., Amor Abda, W., Belhamra, M., & Houhamdi, M. (2014). Eco-ethology of the wintering ferruginous duck Aythya nyroca (Anatidae) in Garaet Hadj Tahar (Guerbes-Sanhadja, Northeast of Algeria). Zoology and Ecology 24 (4): 297-304.   doi:10.1080/21658005.2014.953800

Abstract:

The ecology (phenology and diurnal eco-ethology) of the ferruginous duck Aythya nyroca was studied during three seasons of its wintering (2010/2011, 2011/2012, and 2012/2013) in Garaet Hadj Tahar (a Ramsar site since 2001 with an area of 120 ha, complex of Guerbes-Sanhadja, Skikda, Northeast of Algeria). The maximum number of ferruginous ducks recorded there in December 2012 was 605 individuals. This figure includes the total number of these birds in two populations living at the site: the first one is a nesting sedentary population consisting of about 20 pairs, and the second one, more numerous, frequents the center of this wetland only in wintering seasons. The study of the rhythm of diurnal activities showed that sleeping is the dominant activity of ferruginous ducks accounting for 42.5% of their time budget. It is followed by activities of swimming (20.6%), feeding (19.3%), cleaning (9.3%), and finally, flying (7.7%). Parading constitutes a very small proportion of the time-activity budget of ducks and was not observed until the end of the wintering season. Also, the current study has revealed the role of this wetland in diurnal recovery of ferruginous ducks.

Ferruginous Duck (Aythya nyroca)

Ferruginous Duck (Aythya nyroca). (Photo: Alessandro Musicorio, flickr CC-by-sa).

Biodiversity and phenology of the Rallidae and the Anatidae in Garaet Hadj Tahar (NE Algeria)

Bara, M., Merzoug S., Bouslama Z. & Houhamdi M. (2013). Biodiversity and phenology of the Rallidae and the Anatidae in Garaet Hadj Tahar (Norteast of Algeria). Annals of Biological Research 4 (6): 249-253. PDF

Abstract:

During this study which was carried out between November 2011 and October 2012 in Garaet Hadj Tahar (Northeast of Algeria), we counted the Anatidae and the Rallidae individuals, then we calculated the ecological indexes (Abundance, specific richness, diversity index and equitability index), in order to evaluate the biodiversity in this ecosystem. 14 species were noted which belong to six genera: Fulica, Gallinula, Porphyrio, Anas, Aythya and Oxyura, among them two species cited as threatened species (Ferruginous duck Aythya nyroca and White-headed duck Oxyura leucocephala). The high value of Shannon-Weaver and equitability indexes were recorded during the wintering period with a value of 2.219 and 0.6 respectively.

Garaet Hadj-Tahar (Skikda, Algeria)

Garaet Hadj-Tahar (Skikda, Algeria). From Metallaoui & Houhamdi (2010).

The geographical situation of Garaet Hadj-Tahar (Skikda, Algeria) taken from figure 1 in: Metallaoui, S., & Houhamdi, M. (2010). Biodiversité et écologie de l’avifaune aquatique hivernante dans Garaet Hadj-Tahar (Skikda, Nord-Est de l’Algérie). Hydroécologie Appliquée 17: 1-16.