مسح لأعداء الأسماك في ثلاث مزارع سمكية منتخبة في محافظتي بابل والبصرة، العراق : II. الطيور المائية الضارة والمفترسة

الملخص EN

Enemies of cultivated fishes in fish farms were surveyed, as three fish farms were selected to perform this study, namely Al-Manahel (Al-Belad now) fish farm in Babylon province, Basrah University fish farm at Marine Science Center and Al-Motawah fish farm in Basrah province.

Samples and observations for the study were collected and taken on monthly basis for the period from January to October 2002, as all fish farms were drained at the end of this month.

The study concerned with determining and diagnosing natural fish enemies, their densities and the magnitude of their impact on cultivated fish species.

Water birds belonged to 19 species.

Field observations indicated that water birds counts were 2505, 516 and 141 individuals in Al-Manahel, Basrah University and Al-Motawah fish farms, respectively.

Number of bird species were 17, 13 and 6 in the same localities as above.

Several species of birds, namely herring gull (Larus argentatus), pied kingfisher (Ceryle rudis), white breasted kingfisher (Halcyon smyrnensis), purple heron (Ardea purpurea) and grey heron (A.

cinerea) appeared in all farms, whereas the black headed gull (L.

ridibundus), little egret (Egretta garzetta), great white heron (E.

alba), little bittern (Ixobrychus minutus), black cormorant (Phalacrocorax carbo sinensis) and coot (Fulica atra) were detected in Al-Manahel and Basrah University fish farms.

Common gull (L.

canus) appeared in both farms i.e.

Al-Manahel and Al-Motawah, whereas Al-Manahel was the only fish farm populated by five bird species, namely moorhen (Gallinula chloropus), slender billed gull (L.

genei), little gull (L .minutus), redshank (Tringa totanus) and common kingfisher (Alcedo atthis).

However, avocet (Ricurvirostra avosetta) and black winged stilt (Himantopus himantopus) were only recorded from Basrah University fish farm.