Dull adnabod

Dynodydd

NRW_DS110099

Laith Metadata

English

Datganiad

1996: Case studies of breeding phenology and breeding success were carried out at four colonies in South Pembrokeshire. The count unit adopted was the apparently occupied nest (aon). A colony was defined as any aggregation of nests separated by at least 500 m from the next nearest aggregation. Breeding cormorants were counted by single counts timed to coincide with the main incubation or early chick-rearing stages (late May to early June)At colonies in which studies of breeding biology were being conducted repeat counts throughout the breeding period, also recording the position and status of all nests were taken. This technique allows early failures and late starters to be identified and is therefore the most accurate method. Brood size was monitored at 11 colonies in Wales: four in South Pembrokeshire close to the source of the oil spill , three in Cardigan Bay and four in North Wales. For comparison, data were also collected from three colonies in Devon and one in Caithness. All were visited on at least one occasion when the young were between four weeks old and fledging.

1997: Survey methodology follows that of Cormorant Breeding Colony Survey ( Sellers 1997). Brood size monitored at 8 colonies and three visits were made to St Margaret's Island and Green Scar to monitor breeding success.

Dyddiad cyfeirnod y set ddata (Cyhoeddiad)

1997-11-30

Rhychwant

Rhychwant

Hyd

Wales (WLS)

Hyd

England (ENG)

N

W

E

S

 

Dosbarthiad

Ansawdd

Allweddeiriau

System Cyfeirio Gofodol

Cynnwys

Cyfyngiadau