Seals in Orkney

1985 ◽  
Vol 87 (1-2) ◽  
pp. 95-104 ◽  
Author(s):  
Bernie McConnell
Keyword(s):  
North Sea ◽  
Total Population ◽  
Phoca Vitulina ◽  
Management Policy ◽  
Halichoerus Grypus ◽  
Grey Seal ◽  
Total Population Size ◽  
The North ◽  
The North Sea ◽  
Domestic Use

SynopsisGrey seals (Halichoerus grypus) and common seals (Phoca vitulina) both occur in Orcadian waters. In previous centuries they formed an important resource for both domestic use and export.Annual grey seal pup production has more than doubled since 1964. Productivity on individual islands is influenced by human activity. Total population size is estimated to have risen from around 10,000 in 1964 to around 20,000 in 1982 despite a management policy of culling originally intended to stop population growth. Grey seals tagged in Orkney have been recovered around most parts of the North Sea, Norway, the Faeroes and south to Ireland.Considerably less is known about the biology of common seals in Orkney. A boat survey in 1979 counted 2653 adults and 420 pups.

scholarly journals Identification and real-time PCR quantification of Phocine distemper virus from two colonies of Scottish grey seals in 2002

2005 ◽  
Vol 86 (9) ◽  
pp. 2563-2567 ◽  
Author(s):  
John A. Hammond ◽  
Patrick P. Pomeroy ◽  
Ailsa J. Hall ◽  
Valerie J. Smith
Keyword(s):  
North Sea ◽  
Active Role ◽  
Phoca Vitulina ◽  
Primary Site ◽  
Halichoerus Grypus ◽  
Grey Seal ◽  
Acute Effects ◽  
The North ◽  
Phocine Distemper Virus ◽  
The North Sea

The North Sea European harbour seal (Phoca vitulina) population has endured two phocine distemper virus (PDV) epidemics in 1988 and 2002. The grey seal (Halichoerus grypus) is a sympatric seal species that shows little or no mortality from PDV. Two Scottish grey seal breeding colonies were sampled for evidence of PDV infection approximately 2 months after the peak of the 2002 epidemic. In both colonies, a proportion of mothers (13/109) and pups (6/84) tested positive for PDV in their leukocytes. All infected animals were asymptomatic and completed the breeding season successfully. These results illustrate that grey seals come into contact with infectious seals and can become infected themselves without experiencing acute effects. In some seals the virus is able to replicate from the primary site of infection. This study provides evidence that grey seals may have an active role in the spread of PDV during an epidemic.

Albinistic common seals (Phoca vitulina) and melanistic grey seals (Halichoerus grypus) rehabilitated in the Netherlands

2010 ◽  
Vol 60 (3) ◽  
pp. 273-281 ◽  
Author(s):  
Nynke Osinga ◽  
Pieter 't Hart ◽  
Pieter van Voorst Vader
Keyword(s):  
The Netherlands ◽  
North Sea ◽  
Phoca Vitulina ◽  
Research Centre ◽  
Halichoerus Grypus ◽  
Normal Behaviour ◽  
Delta Area ◽  
The North ◽  
The North Sea ◽  
Photophobic Reaction

AbstractThe Seal Rehabilitation and Research Centre (SRRC) in Pieterburen, The Netherlands, rehabilitates seals from the waters of the Wadden Sea, North Sea and Southwest Delta area. Incidental observations of albinism and melanism in common and grey seals are known from countries surrounding the North Sea. However, observations on colour aberrations have not been systematically recorded. To obtain the frequency of occurrence of these colour aberrations, we analysed data of all seals admitted to our centre over the past 38 years. In the period 1971-2008, 3000 common seals (Phoca vitulina) were rehabilitated, as well as 1200 grey seals (Halichoerus grypus). A total of five albinistic common seals and four melanistic grey seals were identified. This results in an estimated incidence of albinism in common seals of approximately 1/600, and of melanism in grey seals of approximately 1/300. The seals displayed normal behaviour, although in the albinistic animals, a photophobic reaction was observed in daylight.

Cannibalism by a Male Grey Seal (Halichoerus grypus) in the North Sea

2016 ◽  
Vol 42 (2) ◽  
pp. 137-143 ◽  
Author(s):  
Amanda M. Bishop ◽  
Joseph Onoufriou ◽  
Simon Moss ◽  
Paddy P. Pomeroy ◽  
Sean D. Twiss
Keyword(s):  
North Sea ◽  
Halichoerus Grypus ◽  
Grey Seal ◽  
The North ◽  
The North Sea

scholarly journals A Short Investigation into the Habits, Abundance, and Species of Seals on the North Cornwall Coast

1934 ◽  
Vol 19 (2) ◽  
pp. 189-501 ◽  
Author(s):  
G. A. Steven
Keyword(s):  
Relative Abundance ◽  
Direct Evidence ◽  
Phoca Vitulina ◽  
Halichoerus Grypus ◽  
Grey Seal ◽  
The North ◽  
Single Night ◽  
Considerable Size

1. In the course of three trips to the herring grounds in the vicinity of St. Ives five seals were sighted. Seven others were also seen at various other times and places in the course of five days spent in that locality.2. During a single night at sea in Port Isaac Bay eight seals were sighted.3. It was obvious from the movements of certain of the seals observed on the fishing grounds that they were attracted to the herring nets.4. Direct evidence that the seals actually remove fish from the nets was not obtained.5. Damage done to drift nets by seals is negligible.6. Grey Seals (Halichœrus grypus) are present in considerable numbers, and are probably the commonest seals in Cornish waters.7. Brown Seals (Phoca vitulina) appear to be few—they may even be rare—around Cornwall.8. There is at least one seal colony of considerable size in certain caves near Boscastle. This appears to consist of Grey Seals. Probably other such colonies exist on the Cornish coast.9. Clupeoid remains have been found in two out of the three Grey Seal stomachs which have been examined.10. Further and more exact knowledge of the habits and relative abundance of Grey and Brown Seals around the Cornish coast is desirable.

Fatal Interspecies Mating Attempts of a Grey Seal (Halichoerus grypus) with Harbour Seals (Phoca vitulina) on the German North Sea Coast

2020 ◽  
Vol 174 ◽  
pp. 166
Author(s):  
K. Hülskötter ◽  
S. Rohner ◽  
S. Groß ◽  
J. Lakemeyer ◽  
M. Fähndrich ◽  
...  
Keyword(s):  
North Sea ◽  
Phoca Vitulina ◽  
Halichoerus Grypus ◽  
Grey Seal ◽  
Harbour Seals ◽  
Sea Coast ◽  
North Sea Coast

scholarly journals The status of grey seals in Britain

2013 ◽  
Vol 6 ◽  
pp. 69 ◽  
Author(s):  
C D Duck ◽  
D Thompson
Keyword(s):  
Total Population ◽  
Grey Seal ◽  
The North ◽  
Rate Of Increase ◽  
Seal Population ◽  
The Status ◽  
Outer Hebrides ◽  
Likelihood Model ◽  
The North Sea ◽  
The Uk

Grey seal pup production in Scotland was estimated through annual aerial surveys of the main grey seal breeding colonies. Between 3 and 7 counts of pups were obtained for each colony at intervals through the course of the breeding season. Pup production for individual colonies was estimated from the series of counts using a maximum likelihood model. At 3 colonies, 2 in England, annual pup production was estimated using ground counts. Between the early 1960s and the early 1990s, grey seal pup production progressively increased. At colonies in the Inner and Outer Hebrides, production appeared to stabilize during the 1990s and has remained so. Pup production at colonies in Orkney and in the North Sea has continued to increase but in recent years the rate of increase has declined. This may imply that the UK grey seal population is reaching some limit to its size. The observed changes in pup production imply that some density dependent factors are affecting the British grey seal population. Changes in either juvenile survival and/or female fecundity are the most likely options. Without knowing which of these, or what combination of these factors, is operating, estimating total population size is complicated.

scholarly journals Status of grey seals (Halichoerus grypus) in Norway

2007 ◽  
Vol 6 ◽  
pp. 23 ◽  
Author(s):  
Kjell Tormod Nilssen ◽  
Tore Haug
Keyword(s):  
Total Population ◽  
Halichoerus Grypus ◽  
Population Estimates ◽  
Grey Seal ◽  
Breeding Area ◽  
Breeding Sites ◽  
Norwegian Coast ◽  
The North ◽  
Minimum Estimate ◽  
Pup Mortality

During the period September-December in 2001-2003, ship based surveys of grey seal (Halichoerus grypus) pups, including tagging, counting and staging of pups, were conducted along the Norwegian coast. All known and other potential breeding areas were surveyed from Rogaland county in the south to Finnmark county in the north. Most of the breeding sites were surveyed only once, but some sites were surveyed 2-4 times. The investigations resulted in a total minimum estimate of 1,159 grey seal pups born in Norwegian waters. Nordland county was the most important breeding area where about 50% of the pups were born. Total population estimates were derived from the recorded number of pups born using a range of multipliers (4.0-4.7), based on observed annual growth rates of approximately 7-12% in other grey seal populations. This gave a total estimate of about 5,800-6,600 grey seals including pups in Norwegian waters. However, the total pup production was probably underestimated due to only one pup count in most of the breeding sites. Observed mean pup mortality was 1.1% during the breeding season along the Norwegian coast.

Sign in / Sign up

Export Citation Format

Share Document