ABSTRACT The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 Januar... more ABSTRACT The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 January, thanks to the collaboration of 37 participants. The area covered included the entire delta plain and the adjacent coastal sea (over 39,000 ha). Unlike the last two winters, all the rice fields of the northern hemidelta (9,831 ha) were flooded. A total of 96 waterbirds populations were counted, mainly waders (32 species), ducks and geese (20), herons (10), diurnal raptors (9), storks and related groups (6), grebes (4), divers (3), cranes and coots (3), gulls and terns (6), and cormorants (2). In 2013 the most common species of gulls have not been included (Black-headed Gull Larus ridibundus, Mediterranean Gull L. melanocephalus, Yellow-legged Gull L. michahellis and Lesser Black-baked Gull L. fuscus). The waterbird population in January added up to 287,121 birds, value significantly higher than the average of the last 10 years (increase of the +24.1%). The most numerous taxonomical groups have shown important increases (between +11.0 and +107.7%), whereas others (grebes, cormorants, herons, and sterns) have suffered decreases more o less important (between –1.9 and –51.4%). The most numerous species, each with more than 10.000 birds, were Mallard Anas platyrhynchos (73,340 ind.), Dunlin Calidris alpina (38,699 ind.), Eurasian Coot Fulica atra (30,200 ind.), Common Teal Anas crecca (29.769 ind.), Northern Shoveler Anas clypeata (26,869 ind.), Greater Flamingo Phoenicopterus roseus (12,320 ind.) and Northern Lapwing Vanellus vanellus (11.817 ind.). During the census some data about scarce and interesting aquatic birds were obtained, such as Greater White-fronted Goose Anser albifrons (2 ind.), Barnacle Goose Branta leucopsis (1 ind.), Marbled Duck Marmaronetta angustirostris (11 ind.), Ferruginous Duck Aythya nyroca (5 ind.), Common Goldeneye Bucephala clangula (1 ind.), Horned Grebe Podiceps auritus (3 ind.), Red-knobbed Coot Fulica cristata (3 ind.), Temminck's Stint Calidris temminckii (10 ind.), Jack Snipe Lymnocryptes minimus (1 ind.) and Marsh Sandpiper Tringa stagnatilis (1 ind.).
Many authors have examined the possible adaptive value of differences in wing shape between popul... more Many authors have examined the possible adaptive value of differences in wing shape between populations.13 Others have attempted to establish the nature of the relationships existing between wing shape or flight performance and a number of selective pressures, such as niche,46 ...
ABSTRACT The Turtle Dove is a common breeder in Catalonia. It occurs usually from April to Octobe... more ABSTRACT The Turtle Dove is a common breeder in Catalonia. It occurs usually from April to October in a wide variety of habitats, but there are some exceptional winter records near to Barcelona city (2.I.1996; 4.XII.2004). During the sampling period of this study, one juvenile was regularly recorded from November-2008 to February-2009 in the Ebro Delta. Its behaviour suggests that this individual was probably ill or injured and was unable to continue migration. It was finally killed by a hunter and it exhibited active moult.
Cens de la població reproductora de repicatalons ibero-oriental al delta de l'Ebre, 2011 Meto... more Cens de la població reproductora de repicatalons ibero-oriental al delta de l'Ebre, 2011 Metodologia de cens i resultats del cens de 2006
The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 January, thanks... more The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 January, thanks to the collaboration of 37 participants. The area covered included the entire delta plain and the adjacent coastal sea (over 39,000 ha). Unlike the last two winters, all the rice fields of the northern hemidelta (9,831 ha) were flooded. A total of 96 waterbirds populations were counted, mainly waders (32 species), ducks and geese (20), herons (10), diurnal raptors (9), storks and related groups (6), grebes (4), divers (3), cranes and coots (3), gulls and terns (6), and cormorants (2). In 2013 the most common species of gulls have not been included (Black-headed Gull Larus ridibundus, Mediterranean Gull L. melanocephalus, Yellow-legged Gull L. michahellis and Lesser Black-baked Gull L. fuscus). The waterbird population in January added up to 287,121 birds, value significantly higher than the average of the last 10 years (increase of the +24.1%). The most numerous taxonomical groups have ...
ABSTRACT The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 Januar... more ABSTRACT The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 January, thanks to the collaboration of 37 participants. The area covered included the entire delta plain and the adjacent coastal sea (over 39,000 ha). Unlike the last two winters, all the rice fields of the northern hemidelta (9,831 ha) were flooded. A total of 96 waterbirds populations were counted, mainly waders (32 species), ducks and geese (20), herons (10), diurnal raptors (9), storks and related groups (6), grebes (4), divers (3), cranes and coots (3), gulls and terns (6), and cormorants (2). In 2013 the most common species of gulls have not been included (Black-headed Gull Larus ridibundus, Mediterranean Gull L. melanocephalus, Yellow-legged Gull L. michahellis and Lesser Black-baked Gull L. fuscus). The waterbird population in January added up to 287,121 birds, value significantly higher than the average of the last 10 years (increase of the +24.1%). The most numerous taxonomical groups have shown important increases (between +11.0 and +107.7%), whereas others (grebes, cormorants, herons, and sterns) have suffered decreases more o less important (between –1.9 and –51.4%). The most numerous species, each with more than 10.000 birds, were Mallard Anas platyrhynchos (73,340 ind.), Dunlin Calidris alpina (38,699 ind.), Eurasian Coot Fulica atra (30,200 ind.), Common Teal Anas crecca (29.769 ind.), Northern Shoveler Anas clypeata (26,869 ind.), Greater Flamingo Phoenicopterus roseus (12,320 ind.) and Northern Lapwing Vanellus vanellus (11.817 ind.). During the census some data about scarce and interesting aquatic birds were obtained, such as Greater White-fronted Goose Anser albifrons (2 ind.), Barnacle Goose Branta leucopsis (1 ind.), Marbled Duck Marmaronetta angustirostris (11 ind.), Ferruginous Duck Aythya nyroca (5 ind.), Common Goldeneye Bucephala clangula (1 ind.), Horned Grebe Podiceps auritus (3 ind.), Red-knobbed Coot Fulica cristata (3 ind.), Temminck's Stint Calidris temminckii (10 ind.), Jack Snipe Lymnocryptes minimus (1 ind.) and Marsh Sandpiper Tringa stagnatilis (1 ind.).
Many authors have examined the possible adaptive value of differences in wing shape between popul... more Many authors have examined the possible adaptive value of differences in wing shape between populations.13 Others have attempted to establish the nature of the relationships existing between wing shape or flight performance and a number of selective pressures, such as niche,46 ...
ABSTRACT The Turtle Dove is a common breeder in Catalonia. It occurs usually from April to Octobe... more ABSTRACT The Turtle Dove is a common breeder in Catalonia. It occurs usually from April to October in a wide variety of habitats, but there are some exceptional winter records near to Barcelona city (2.I.1996; 4.XII.2004). During the sampling period of this study, one juvenile was regularly recorded from November-2008 to February-2009 in the Ebro Delta. Its behaviour suggests that this individual was probably ill or injured and was unable to continue migration. It was finally killed by a hunter and it exhibited active moult.
Cens de la població reproductora de repicatalons ibero-oriental al delta de l'Ebre, 2011 Meto... more Cens de la població reproductora de repicatalons ibero-oriental al delta de l'Ebre, 2011 Metodologia de cens i resultats del cens de 2006
The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 January, thanks... more The 2013 Mid-Winter Waterbirds Census was held in the Ebro Delta between 7 and 30 January, thanks to the collaboration of 37 participants. The area covered included the entire delta plain and the adjacent coastal sea (over 39,000 ha). Unlike the last two winters, all the rice fields of the northern hemidelta (9,831 ha) were flooded. A total of 96 waterbirds populations were counted, mainly waders (32 species), ducks and geese (20), herons (10), diurnal raptors (9), storks and related groups (6), grebes (4), divers (3), cranes and coots (3), gulls and terns (6), and cormorants (2). In 2013 the most common species of gulls have not been included (Black-headed Gull Larus ridibundus, Mediterranean Gull L. melanocephalus, Yellow-legged Gull L. michahellis and Lesser Black-baked Gull L. fuscus). The waterbird population in January added up to 287,121 birds, value significantly higher than the average of the last 10 years (increase of the +24.1%). The most numerous taxonomical groups have ...
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