Status of Breeding Common Scoter Melanitta nigra nigra in Britain and Ireland in 1996: The Effect of the Sea Empress Oil Spill

Following concerns regarding potential effects of the Sea Empress oil spill in Carmarthen Bay, February 1996, on the British and Irish populations of breeding Common Scoters Melanitta nigra nigra, their status and distribution were determined from a survey in May - June 1996. The survey was undertaken in five areas (Shetland, the Flow country, West and South Scotland, Islay and Ireland), using methods devised during the first complete British and Irish census of this species in 1995. Survey effort was concentrated on sites that held Common Scoters in 1995, and on sites with historical records. The survey visited 223 sites and located 376 birds. This was 79 fewer birds than the previous year, a 17% decline in numbers (16% in Ireland and 19% in Britain), a 19% decrease in occupied 10-km squares and a 31% decrease in occupied sites, compared to visits made at a similar time in 1995. It is possible that a decline of this magnitude may be within the range of natural population fluctuations or it could be due to the late arrival of birds after the late spring in 1996. However, over the last eight years, the number of Common Scoters in the Flow country has declined by 42% from an estimated 48 pairs in 1988 to only 28 in 1996. Given the Common Scoter's threatened status in the UK, that the dynamics of the population are unknown, and the potential decline, annual monitoring of both numbers and productivity is a high priority. Data used to assess the potential effects of the Sea Empress oil spill in Carmarthen Bay, February 1996, on the British and Irish populations of breeding Common Scoters Melanitta nigra nigra.

Identification

Identifier
NRW_DS110113
Alternative Title
  • Statws mor-hwyaid duon melanitta nigra nigra oedd yn nythu ym Mhrydain ac Iwerddon yn 1996: effaith gollyngiad olew'r Sea Empress
Metadata Language
English
Lineage

Sites on the Scottish mainland were surveyed from 12-18 May and Islay was surveyed on 7 June. In Ireland, Loughs Conn/Cullin, Corrib and Arrow were surveyed between 16-19 May, but surveys of Lough Ree were delayed until 22-25 May by poor weather. During each survey, all open water and the entire mainland and island shorelines were scanned for birds using binoculars or telescopes. Most observations were land based, but boat surveys were used on larger and complex sites. Clear, calm weather was selected for all field visits and observers recorded the number of birds present, classified into pairs (male and female in continuous close consort), single adult males, single immature males, unaged males, single females and unsexed birds. To minimise the risk of double counting birds, where possible, surveys were organised to cover adjacent sites simultaneously. In order to investigate whether there had been any decline in numbers between 1995 and 1996, the numbers of birds present per site were analysed using a generalised linear model with Poisson error distribution and log link function in the GLIM statistical package. Sites were selected for analysis if birds were present either during the 1996 survey, or during the comparable visit in 1995. Four explanatory variables were included in the model: sex, area, site, and year.
Dataset Reference Date (Publication)
1996-08-31
Owner
  Natural Resources Wales (NRW)
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
Originator
  Royal Society for the Protection of Birds (RSPB)
Sutherland House, Cowbridge Road East, Cardiff, CF11 9AB
http://www.rspb.org.uk/wales/
Originator
  Wildfowl And Wetlands Trust (WWT)
Wildfowl and Wetlands Trust (WWT), Slimbridge, Gloucestershire, GL2 7BT, England
http://www.wwt.org.uk/
Originator
  Scottish Natural Heritage (SNH)
Great Glen House, Leachkin Road, Inverness, IV3 8NW
http://www.snh.gov.uk/
 

Extent

Extent

Geographic Extent
Great Britain (GBN)
N
W
E
S
Map representing the geographic extent of the dataset


 

Vertical Extent

Medin Extent Keyword

water column skin; bathypelagic water column
 
 

Distribution

Format Type and Description
  • Documents ()

    Specification

    Report is held in Word and .pdf format

 

Quality

Data quality

Quality Scope
Dataset
Conformity
Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services
Explanation
Degree
false
Lineage

Sites on the Scottish mainland were surveyed from 12-18 May and Islay was surveyed on 7 June. In Ireland, Loughs Conn/Cullin, Corrib and Arrow were surveyed between 16-19 May, but surveys of Lough Ree were delayed until 22-25 May by poor weather. During each survey, all open water and the entire mainland and island shorelines were scanned for birds using binoculars or telescopes. Most observations were land based, but boat surveys were used on larger and complex sites. Clear, calm weather was selected for all field visits and observers recorded the number of birds present, classified into pairs (male and female in continuous close consort), single adult males, single immature males, unaged males, single females and unsexed birds. To minimise the risk of double counting birds, where possible, surveys were organised to cover adjacent sites simultaneously. In order to investigate whether there had been any decline in numbers between 1995 and 1996, the numbers of birds present per site were analysed using a generalised linear model with Poisson error distribution and log link function in the GLIM statistical package. Sites were selected for analysis if birds were present either during the 1996 survey, or during the comparable visit in 1995. Four explanatory variables were included in the model: sex, area, site, and year.
 

Keywords

Keywords

GEMET - INSPIRE themes, version 1.0
Type
Theme

Citation

Date (Publication)
2008-06-01
Code
geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme

Keywords

NRW Thesaurus
  • breeding
  • breeding birds
  • common scoter (black scoter)
  • melanitta nigra
  • Carmarthen Bay
  • distributions
  • survey methods (survey techniques) (survey) (surveying)
  • Shetland
  • Flow country
  • west Scotland
  • South Scotland
  • Islay
  • endangered species (threatened species)(protected species)
  • marine and freshwater inventory
Type
Theme

Citation

Date (Publication)
2023-12-31
Code
geonetwork.thesaurus.local.theme.converted_nrw-keywords

Keywords

SeaDataNet Parameter Discovery Vocabulary
  • Bird taxonomy-related abundance per unit area of surface
Type
Theme

Citation

Date (Revision)
2021-01-06
Code
geonetwork.thesaurus.external.theme.rdf+xml
 

Spatial Reference System

Code
British National Grid (EPSG::27700)
 

Content

Content Information

NRW Profile

Custom Elements

NRW Related Title

The status of breeding common scoter melanitta nigra nigra in Britain and Ireland in 1996 : the effect of the Sea Empress oil spill
NRW Related Title

All Wales common scoter survey : report on 2001/02 work programme
NRW Related Title

All Wales common scoter survey : report on 2002/03 work programme
NRW Related Title

All Wales common scoter survey : report on 2003/2004 work programme
NRW Related Title

Common scoter Melanitta nigra monitoring in Carmarthen Bay following the Sea Empress oil spill
NRW Related Title

Common scoter monitoring in Carmarthen Bay following the Sea Empress oil spill. April 1997 to March 1998
 

Constraints

Constraints

Limitations on Public Access and Use

Restriction type
Other restrictions
 

Access Constraints Directive

Limitations
no limitations
 

Access Constraints Text

Other constraints

There are no access restrictions to this data. NRW may release, publish or disseminate it freely.
 

Use Constraints

Use constraints type
Other restrictions
Other constraints

© CNC/NRW Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and NRW's copyright. It is the recipient's responsibility to ensure the data is fit for the intended purpose.
 
 
 

Metadata

Metadata

File Identifier
4f4c4942-4343-5764-6473-313130313133 XML
Metadata Language
English
Resource type
Dataset
Metadata Date
2024-05-31T09:41:08.808Z
Metadata Standard Name
NRW
Metadata Standard Version

1.0

pointOfContact
  Natural Resources Wales (NRW)
Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales
http://naturalresources.wales/?lang=en
 
 

Publishing Body

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