Breeding ecology of Turtle Doves (Streptopelia turtur) on intensively cultivated farmland

Hanane, S. (2016). Effects of location, orchard type, laying period and nest position on the reproductive performance of Turtle Doves (Streptopelia turtur) on intensively cultivated farmland. Avian Research 7: 4.  doi: 10.1186/s40657-016-0039-0 (Open Access)

Abstract

Background
Until recently little was known about factors affecting reproductive parameters of the Turtle Dove (Streptopelia turtur) on intensively cultivated farmland in the Mediterranean area. In this study, the reproductive parameters of this game species were evaluated in relation to location, orchard type, laying period and nest position in central Morocco.

Methods
A total of 317 nests were found and analyzed across five breeding seasons (2004–2008) in the Haouz and Tadla regions, over two major agro-ecosystems made up of olive and orange orchards. Nest position, laying period, clutch size and the number of chicks hatched and fledged per nest were determined on 120 study plots. I used Generalized Linear Models (GLMs) with a Poisson distribution and a log link function, including the logarithm of the number of eggs in each clutch as an offset to model the number of chicks hatched and fledged per nest.

Results
Clutch-size was not affected by location, orchard type, laying period or nest position. The number of chicks hatched per nest differed between orchard types; they were greater in olive orchards (1.33 ± 0.06) than in orange ones (1.03 ± 0.08), whereas the number of chicks fledged per nest consistently differed with laying period and orchard type, which were higher in the early laying period (1.22 ± 0.07) than in the late period (0.93 ± 0.08) and higher in olive orchards (1.22 ± 0.06) than in orange orchards (0.90 ± 0.06). Neither location nor nest position were related to variation in the fledging success of the Turtle Dove.

Conclusions
Olive orchards and the early laying period confer better nesting conditions than orange orchards and the late laying period. Although nest position could be different in each orchard type, it did not affect the breeding success of the Turtle Dove, suggesting that factors other than tree characteristics are influential. Further studies are needed to improve our understanding of the effects of anthropogenic disturbance, especially agricultural activities and hunting, on the productivity of Turtle Dove nests.

 

Turtle Doves: nest with two eggs, newly hatched chick, and adult at nest with its chicks

a) A nest of a Turtle Dove with two eggs on an olive tree. b) A nest of Turtle Dove with a newly hatched chick on an orange tree. c) A Turtle Dove at nest with its chicks on an orange tree (Saâd Hanane)

 

 

Nest-niche differentiation in two sympatric Streptopelia species from a North African agricultural area

Hanane, S. (2015). Nest-niche differentiation in two sympatric Streptopelia species from a North African agricultural area: the role of human presence. Ecological Research 30: 573–580. doi: 10.1007/s11284-015-1259-1

Abstract:

Studies of niche partitioning among Columbidae species have mainly addressed food habits and foraging activities, while partitioning in relation to nest-niche differentiation has been little studied. The recent expansion of Laughing dove Streptopelia senegalensis distribution throughout Morocco has raised concerns regarding its effects on native species, particularly Turtle doves S. turtur. The study, conducted in May 2008 and 2009, attempted to determine the factors that may play a role in nest-niche differentiation among the two sympatric dove species in the Tadla’s agricultural area (central Morocco). I used Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) to test the relevance of nest placement and human presence variables in the nest distribution of the two species. The results show substantial niche segregation in the olive nest-trees selected by Turtle and Laughing doves, with selection depending primarily on human presence and, to a lesser extent, the vertical distribution of nests. Observed nest-niche partitioning may diminish the potential for competition between these species and enhance opportunities for their coexistence. I further suggest guidelines for future studies that seek to understand the spatio-temporal dynamics of Laughing and Turtle dove coexistence in the region.

Les facteurs déterminants le succès de reproduction de la Tourterelle des bois (Streptopelia turtur) dans un milieu agricole Nord-Africain

Kafi, F., Hanane, S., Bensouilah, T., Zeraoula, A., Brahmia, H. & Houhamdi, M. 2015. Les facteurs déterminants le succès de reproduction de la Tourterelle des bois (Streptopelia turtur) dans un milieu agricole Nord-Africain. Revue d’Ecologie (Terre et Vie) 70 (3): 271-279.
PDF in ResearchGate.net

Summary:

Determinants of nesting success in Turtle doves (Streptopelia turtur) in a North-African agricultural area. Determining the effects of environmental factors on nesting success of migrant and breeding game birds is paramount especially in man-made environments. Using Poisson regression, we investigated the influence on the number of chicks fledged per nest (N = 207) of nest placement, proximity of cereal crops and water sources, taking into account possible phenological and spatial differences between the five studied orchards. The best model, selected by Akaike criterion, shows positive linear effects of distance from the nest to the trunk, to closest cereal crops and a quadratic effect of nest height (with an optimum at 1.6m). In Guelma’s orange groves, nest placement and proximity to cereal crops have a direct impact on the productivity of Turtle doves. Further researches on other tree species (fruit and forest ones) are necessary to: (i) assess their importance for breeding Turtle doves and (ii) determine the effect of environmental variables on the maintenance of the species.

Résumé:

Connaître les effets des facteurs écologiques sur le succès de la reproduction de l’avifaune migratrice nicheuse est primordial particulièrement dans les milieux artificialisés. Nous avons étudié, au moyen de régressions de Poisson, l’influence de l’emplacement des nids sur les arbres, de la proximité aux cultures céréalière et aux points d’eau sur le nombre de jeunes à l’envol par nid (N=207), en tenant compte de possibles différences phénologiques et spatiales entre les cinq vergers étudiés. Le meilleur modèle, sélectionné sur la base du critère d’Akaike, montre des effets linéaires positifs de la distance du nid au tronc et aux plus proches cultures céréalières, et un effet quadratique de la hauteur du nid (avec un optimum à 1,6m). Dans les orangeraies de Guelma, le positionnement des nids et leur proximité aux cultures céréalières ont une incidence directe sur la productivité totale des Tourterelles des bois. La poursuite des recherches sur d’autres supports de nidification (arbres fruitiers et forestiers) s’avère nécessaire pour : (i) évaluer leur importance pour la reproduction de l’espèce et (ii) connaître l’effet des variables environnementales sur le maintien de l’espèce.

Tourterelle des bois (Streptopelia turtur), Algérie

Tourterelle des bois (Streptopelia turtur), Algérie (photo: Taamallah Chamsi)

Breeding biology of sympatric Laughing (Streptopelia senegalensis) and Turtle (Streptopelia turtur) Doves in NE Algeria

Brahmia, H., Zeraoula, A., Bensouilah, T., Bouslama, Z., & Houhamdi, M. 2015. Breeding biology of sympatric Laughing Streptopelia senegalensis and Turtle Streptopelia turtur Dove: a comparative study in northeast Algeria. Zoology and Ecology  25(3): 220–226.   doi: 10.1080/21658005.2015.1049470
PDF in ResearchGate.net

Abstract:

The Turtle Dove and Laughing Dove display distinct behavior and are morphologically and genetically different. However, microhabitat selection and reproductive success details of the two species are still poorly studied. The geographic distribution of the Laughing Dove in North Africa has clearly expanded nowadays. The breeding ecology and nest placement of this species have been studied previously, but little is currently known about its life history in Algeria. This study aimed to provide the basic information on the breeding biology of the Laughing Dove in Algeria. During two consecutive breeding seasons (2013–2014), the clutch size, brood size, chick survival, timing of breeding, densities of breeding pairs, nest placement, and the main causes of nest failure of the sympatric Laughing Dove and Turtle Dove were studied in an olive orchard in Guelma region, northeast Algeria. Clutch size, brood size, chick survival, the estimated productivity, and nest placement of the two species were similar but timing of breeding and population densities were significantly different. Finally, the largely coincident egg-laying period and the similar clutch size of the two species seem to be the main factors behind their similar survival rate and productivity in our study area.

Laughing Dove (Streptopelia senegalensis), Helwan, Egypt

Laughing Dove (Streptopelia senegalensis), Helwan, Egypt (Rachid H., flickr)