Gibraltar Ornithological and Natural History Society GONHS

Upper, Gibraltar

Gibraltar Ornithological and Natural History Society GONHS

Upper, Gibraltar
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Schurr M.R.,University of Notre Dame | Fuentes A.,University of Notre Dame | Luecke E.,Healthy Communities Institute | Cortes J.,Gibraltar Ornithological and Natural History Society GONHS | Shaw E.,Gibraltar Ornithological and Natural History Society GONHS
Primates | Year: 2012

Interactions with humans impact many aspects of behavior and ecology in nonhuman primates. Because of the complexities of the human-nonhuman primate interface, methods are needed to quantify the effects of anthropogenic interactions, including their intensity and differential impacts between nonhuman primate groups. Stable isotopes can be used to quickly and economically assess intergroup dietary variation, and provide a framework for the development of specific hypotheses about anthropogenic impact. This study uses stable carbon and nitrogen isotope analysis to examine intraspecific variation in diet between five groups of Barbary macaques, Macaca sylvanus, in the Upper Rock Nature Reserve, Gibraltar. Analysis of hair from 135 macaques showed significant differences in δ13C and δ15N values between a group with minimal tourist contact and groups that were main tourist attractions. Because we observed no overt physiological or substantial behavioral differences between the groups, feeding ecology is the most likely cause of any differences in stable isotope ratios. Haphazard provisioning by tourists and Gibraltarians is a likely source of dietary variation between groups. Stable isotope analysis and observational data facilitate a deeper understanding of the feeding ecology of the Barbary macaques relevant to the role of an anthropogenic ecology for the species. © 2011 Japan Monkey Centre and Springer.


Zduniak P.,Adam Mickiewicz University | Yosef R.,Ben - Gurion University of the Negev | Bensusan K.J.,University of Gibraltar | Perez C.E.,Gibraltar Ornithological and Natural History Society GONHS | Tryjanowski P.,University of Life Sciences in Poznań
ZooKeys | Year: 2015

The Mediterranean Sea is known as an ecological barrier for numerous migratory birds flying from European breeding grounds to African wintering sites. Birds generally avoid migration over open sea and fly over land. In the Mediterranean Basin, few land bridges or bottlenecks for migratory birds exist. The narrowest are at the western and eastern extremes: the Strait of Gibraltar and Israel. Comparative studies between these locations are extremely rare to date. Therefore, in order to elucidate the differences between the two flyways, we compared data collected simultaneously for two sister leaf warbler species, the Bonelli’s Warbler complex, Phylloscopus bonelli and Ph. orientalis, at ringing stations in the western Mediterranean Basin Gibraltar, and the eastern Eilat, Israel. Data on biometrics and passage dates of individuals trapped at Gibraltar and Eilat were used, and it was found that mean arrival date of Western Bonelli’s Warblers at Gibraltar was 15 days later than Eastern Bonelli’s Warblers at Eilat. Furthermore, Western Bonelli’s Warblers had shorter wings than Eastern Bonelli’s Warblers. On the other hand, birds in Eilat were in poorer body condition than individuals in Gibraltar. The comparison between geographically distant stop-over sites contributes to furthering our understanding of the development of migration strategies across ecological barriers in sibling species. Our study showed that populations that breed in southwestern Europe migrate through Gibraltar and winter in West Africa are able to accomplish migration in comparatively good body condition. This is in contrast to those that winter in East Africa, migrate through Israel and have to endure the combined challenge of crossing the Sahel, Sahara and Sinai deserts before reaching their breeding grounds across southeast Europe and southwest Asia. Hence, the discrepancies described between the western and the eastern flyway suggest that individuals in the west, in general, migrate shorter distances, have a physiologically less demanding crossing of the North African deserts and appear to stage before their crossing the Strait of Gibraltar, a privilege unavailable to the migrants of the eastern flyway. © 2015, Pensoft Publishers. All rights reserved.


Amezian M.,Abdelmalek Essaadi University | Cortes J.,Gibraltar Ornithological and Natural History Society GONHS | Thompson I.,Gibraltar Ornithological and Natural History Society GONHS | Bensusan K.,Gibraltar Ornithological and Natural History Society GONHS | And 4 more authors.
Ardea | Year: 2010

A complete moult north of the Sahara has never been reported conclusively in the Reed Warbler Acrocephalus scirpaceus complex. During a ringing program carried out in the Smir marshes (northern Morocco) 140 adults and 292 juvenile Reed Warblers were examined during four autumns in the period 2004-2008. Of these birds, 8.9% of juveniles were either in active moult (n = 17) or had completed moult (n = 9) and 48.6% of adults were either in active moult (n = 32) or completely moulted (n = 22). At least some of the moulting birds were of local origin (i.e. Smir breeding population), since 14 males and one female were captured in autumn and later recaptured in spring showing signs of breeding activity, or captured In spring and recaptured moulting in autumn. Also, one juvenile captured in May was recaptured in November while moulting. Capture history of some moulting birds indicate that they over-winter locally and others most likely winter somewhere else In Morocco (i.e. north of the Sahara). Therefore, we report the discovery of a (partly) sedentary population of an as yet undescribed taxon of Reed Warblers In Smir marshes, Morocco. The relationship of these to the Eurasian A. scirpaceus and African A. baeticatus Reed Warblers remains to be investigated.


Bensusan K.J.,Gibraltar Ornithological and Natural History Society GONHS | Nesbit R.,Society of Biology | Perez C.E.,Gibraltar Ornithological and Natural History Society GONHS | Tryjanowski P.,University of Life Sciences in Poznań | Zduniak P.,Adam Mickiewicz University
European Journal of Entomology | Year: 2014

In order to understand patterns of abundances of migratory Lepidoptera in southernmost Europe and contrast this with those of sedentary species, we studied butterflies surveyed along transects during three spring migration seasons at the Rock of Gibraltar. Overall, 2508 butterflies belonging to 19 species were recorded. Of these, the four most numerous species accounted for almost 88% of all individuals recorded. These were the migratory Clouded Yellow Colias croceus, Red Admiral Vanessa atalanta and Painted Lady Vanessa cardui, and the sedentary Common Blue Polyommatus icarus. There was a significant correlation between abundance of P. icarus and C. croceus. Furthermore, abundances of C. croceus and V. atalanta were correlated. The sometimes very high abundance of migratory butterflies at the study site could suggest that Gibraltar is a stopover site for butterflies migrating between Africa and Europe.


Amezian M.,Abdelmalek Essaadi University | Thompson I.,Gibraltar Ornithological and Natural History Society GONHS | Bensusan K.,Gibraltar Ornithological and Natural History Society GONHS | Cortes J.,Gibraltar Ornithological and Natural History Society GONHS | And 2 more authors.
Ostrich | Year: 2011

The Eurasian Penduline Tit Remiz pendulinus was until recently considered to be an accidental winter visitor to Morocco. Regular wintering was suspected in the north-west of the country but had been poorly documented. The ringing data collected in the Smir marshes (north-west Morocco) during the period 2004-2008 indicate that Eurasian Penduline Tits regularly winter in Morocco. During the study period, 50 birds were caught on 68 occasions. The intra-seasonal recapture data, i.e. autumn to the following spring, and winter observations showed that some individuals over-wintered locally at this site. The inter-annual recapture data indicate that wintering birds return regularly to the Smir marshes. © NISC (Pty) Ltd.


PubMed | Adam Mickiewicz University, Ben - Gurion University of the Negev, University of Gibraltar, University of Life Sciences in Poznań and Gibraltar Ornithological and Natural History Society GONHS
Type: | Journal: ZooKeys | Year: 2015

The Mediterranean Sea is known as an ecological barrier for numerous migratory birds flying from European breeding grounds to African wintering sites. Birds generally avoid migration over open sea and fly over land. In the Mediterranean Basin, few land bridges or bottlenecks for migratory birds exist. The narrowest are at the western and eastern extremes: the Strait of Gibraltar and Israel. Comparative studies between these locations are extremely rare to date. Therefore, in order to elucidate the differences between the two flyways, we compared data collected simultaneously for two sister leaf warbler species, the Bonellis Warbler complex, Phylloscopus bonelli and Phylloscopus orientalis, at ringing stations in the western Mediterranean Basin Gibraltar, and the eastern Eilat, Israel. Data on biometrics and passage dates of individuals trapped at Gibraltar and Eilat were used, and it was found that mean arrival date of Western Bonellis Warblers at Gibraltar was 15 days later than Eastern Bonellis Warblers at Eilat. Furthermore, Western Bonellis Warblers had shorter wings than Eastern Bonellis Warblers. On the other hand, birds in Eilat were in poorer body condition than individuals in Gibraltar. The comparison between geographically distant stop-over sites contributes to furthering our understanding of the development of migration strategies across ecological barriers in sibling species. Our study showed that populations that breed in southwestern Europe migrate through Gibraltar and winter in West Africa are able to accomplish migration in comparatively good body condition. This is in contrast to those that winter in East Africa, migrate through Israel and have to endure the combined challenge of crossing the Sahel, Sahara and Sinai deserts before reaching their breeding grounds across southeast Europe and southwest Asia. Hence, the discrepancies described between the western and the eastern flyway suggest that individuals in the west, in general, migrate shorter distances, have a physiologically less demanding crossing of the North African deserts and appear to stage before their crossing the Strait of Gibraltar, a privilege unavailable to the migrants of the eastern flyway.

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