Harbour porpoises (Phocoena phocoena) in north-western France: aerial survey, opportunistic sightings and strandings monitoring

The harbour porpoise (Phocoena phocoena) is one of the common small cetaceans of European waters. This discreet and undemonstrative species is strongly represented throughout the cold waters of the northern hemisphere, and is the most abundant cetacean in the North Sea. In the last few years, some observations and studies indicate a shift of harbour porpoise distribution in European waters, from northern regions of the North Sea to the southern North Sea, English Channel and Celtic Sea. This shift may include a comeback around the coasts of France. Harbour porpoises inhabit shelf-waters and are often observed in shallow waters, conditions offered for instance by the coasts of Brittany in north-western France. We used opportunistic sightings, aerial survey and a ten-year strandings database to study the presence of harbour porpoises along the coasts of Brittany. Opportunistic sightings made by non-specialists did not confirm a strong presence of harbour porpoises along the Brittany coasts, most probably because of the undemonstrative behaviour of this cetacean. However, aerial survey and stranding analysis indicate that harbour porpoises have become natural inhabitants of the Brittany coasts once more: 68.6% of cetacean school sightings made during a 1578 km aerial survey of the Brittany coasts concerned harbour porpoises, with an encounter rate of 1.5 individuals per 100 km that peaked to 5.8 per 100 km to the top of the shallow waters of the south-western Western English Channel. The number of harbour porpoise strandings increased each year from 1997 to 2007, making a total of 135 along the coasts of Brittany. Other cetaceans did not show such an increase during the same period. Strandings of harbour porpoises were also characterized by an apparent increase as a proportion in relation to all the cetacean strandings during the months of September to January, by a marked impact of by-catch during winter, and by an almost total absence of stranded calves. The comeback of the harbour porpoise along Brittany coasts is clearly confirmed by our data, and a stable population seems to be established again along the coasts of Brittany. This tends to confirm the shift of the distribution of the species in certain European waters. Long term monitoring, diet and genetic studies are now planned for a better understanding of this shift, and for the effective implementation of a conservation plan.

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Harbour porpoise (Phocoena phocoena) presence, abundance and distribution over the Dogger Bank, North Sea, in winter

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315416000783 ◽

2016 ◽

Vol 97 (7) ◽

pp. 1455-1465 ◽

Cited By ~ 2

Author(s):

A.-C. Cucknell ◽

O. Boisseau ◽

R. Leaper ◽

R. McLanaghan ◽

A. Moscrop

Keyword(s):

North Sea ◽

Probability Of Detection ◽

Harbour Porpoise ◽

Encounter Rate ◽

Phocoena Phocoena ◽

Survey Area ◽

The West ◽

Dogger Bank ◽

The North ◽

The North Sea

An area in the central North Sea was surveyed in November 2011 in order to estimate the abundance and density of harbour porpoises (Phocoena phocoena). A total of 2833 km of pre-determined trackline were acoustically surveyed, of which 28% included visual effort. The poor sighting conditions during the survey limited visual effort and demonstrated the advantage of using acoustic techniques for studying harbour porpoise in winter months. Absolute abundance and density estimates were calculated from acoustic encounter rates using estimates of probability of detection and mean group size. The density of harbour porpoises in the west of the survey area was almost double that in the east, with UK waters to the south-west of the Dogger Bank having the highest density of the area surveyed. The overall acoustic encounter rate was higher than most other surveys in the North Sea. The mean density across the survey area of 0.63 (95% CI 0.27–1.52) individuals km−2and distribution of porpoises was similar to that documented in the summer suggesting that high abundance of harbour porpoises in the west of the North Sea is not confined to summer months. This information is particularly relevant given plans for the construction of a large offshore wind farm on the UK section of the Dogger Bank; the resulting impacts, including acoustic disturbance from pile driving, will potentially affect substantial numbers of harbour porpoises.

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Identification of the first harbour porpoise (Phocoena phocoena) calving ground in the North Sea

Journal of Sea Research ◽

10.1016/s1385-1101(98)00050-1 ◽

1999 ◽

Vol 41 (3) ◽

pp. 225-232 ◽

Cited By ~ 15

Author(s):

R.P Sonntag ◽

H Benke ◽

A.R Hiby ◽

R Lick ◽

D Adelung

Keyword(s):

North Sea ◽

Harbour Porpoise ◽

Phocoena Phocoena ◽

The North ◽

The North Sea

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Cutaneous papillomavirus infection in a harbour porpoise (Phocoena phocoena) from the North Sea

Veterinary Record ◽

10.1136/vr.144.21.592 ◽

1999 ◽

Vol 144 (21) ◽

pp. 592-593 ◽

Cited By ~ 13

Author(s):

M.-F. Van Bressem ◽

R. A. Kastelein ◽

P. Flamant ◽

G. Orth

Keyword(s):

North Sea ◽

Harbour Porpoise ◽

Phocoena Phocoena ◽

The North ◽

Papillomavirus Infection ◽

The North Sea

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Mercury contamination of the harbour porpoise Phocoena phocoena and other cetaceans from the North Sea and the kattegat

Water Air & Soil Pollution ◽

10.1007/bf00342277 ◽

1991 ◽

Vol 56 (1) ◽

pp. 283-293 ◽

Cited By ~ 37

Author(s):

C. R. Joiris ◽

L. Holsbeek ◽

JM. Bouquegneau ◽

M. Bossicart

Keyword(s):

North Sea ◽

Harbour Porpoise ◽

Mercury Contamination ◽

Phocoena Phocoena ◽

The North ◽

The North Sea

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Further Investigation upon the Water Movements in the English Channel. Drift-Bottle Experiments in the Summers of 1927, 1928 and 1929, with Critical Notes on Drift-Bottle Experiments in General.

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400051869 ◽

1930 ◽

Vol 17 (1) ◽

pp. 241-275 ◽

Cited By ~ 15

Author(s):

J. N. Carruthers

Keyword(s):

Wind Speed ◽

North Sea ◽

English Channel ◽

The North ◽

Different Types ◽

The North Sea ◽

The Common ◽

Relationship Of ◽

Great Simplicity ◽

Simple Surface

In July–August of three different years common surface-floating bottles were set adrift at International Station E2 (49° 27' N.—4° 42' W.). With them, various types of drag-fitted bottles were also put out. The journeys accomplished are discussed, and the striking differences as between year and year in the case of the common surface floaters, and as between the different types in the same year, are commented upon in the light of the prevailing winds. An inter-relationship of great simplicity is deduced between wind speed and the rate of travel of simple surface floating bottles up-Channel and across the North Sea from the results of experiments carried out in four different summers.

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Temperature, Salinity and Plankton in the Eastern North Atlantic and Coastal Waters of Britain, 1957.: I. The Characterisation and Distribution of Surface Waters

Journal of the Fisheries Research Board of Canada ◽

10.1139/f63-052 ◽

1963 ◽

Vol 20 (3) ◽

pp. 789-826 ◽

Cited By ~ 11

Author(s):

B. McK. Bary

Keyword(s):

North Sea ◽

North Atlantic ◽

Coastal Waters ◽

Water Bodies ◽

English Channel ◽

Oceanic Water ◽

Climatic Fluctuations ◽

The North ◽

The North Sea ◽

Eastern North Atlantic

Monthly temperature-salinity diagrams for 1957 have demonstrated that three surface oceanic "water bodies" were consistently present in the eastern North Atlantic; two are regarded as modified North Atlantic Central water which give rise to the third by mixing. As well in the oceanic areas, large and small, high or low salinity patches of water were common. Effects of seasonal climatic fluctuations differed in the several oceanic water bodies. In coastal waters, differences in properties and in seasonal and annual cycles of the properties distinguish the waters from the North Sea, English Channel and the western entrance to the Channel.The geographic distributions of the oceanic waters are consistent with "northern" and "southern" water bodies mixing to form a "transitional" water. Within this distribution there are short-term changes in boundaries and long-term (seasonal) changes in size of the water bodies.Water in the western approaches to the English Channel appeared to be influenced chiefly by the mixed, oceanic transitional water; oceanic influences in the North Sea appear to have been from northern and transitional waters.

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1.—The Competitors and the Result

Aeronautical journal (London England 1897) ◽

10.1017/s2398187300146730 ◽

1906 ◽

Vol 10 (40) ◽

pp. 50-51

Keyword(s):

Great Britain ◽

North Sea ◽

English Channel ◽

Long Distance ◽

The North ◽

The North Sea ◽

The Way

No fewer than seven nations tried to win the Gordon Bennett Cup in the race which started from the Tuileries Gardens, in Paris, on September 30th. But the wind was in an unfavourable direction for the accomplishment of a long distance record. To some, the English Channel barred the way, to some, the North Sea.The cup offered for the greatest distance covered has been accorded to the American aeronaut, Mr. Frank P. Lahm, who descended 15 miles north of Scarborough.It will be seen in another part of this Journal that in December next, Members of the Aëronautical Society of Great Britain will hear an account of the Gordon-Bennett race from Colonel J. E. Capper, who took part in the race, having accompanied Mr. Rolls in the “ Britannia.” In this account, therefore, it will suffice to merely tabulate the competitors and results.

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Thinlip grey mullet Liza ramada (Mugilidae) caught in a

Fauna norvegica ◽

10.5324/fn.v26i0.571 ◽

2008 ◽

Vol 26 ◽

Author(s):

Bror Jonsson ◽

Nina Jonsson

Keyword(s):

North Sea ◽

Total Mass ◽

First Year ◽

English Channel ◽

Grey Mullet ◽

Font Size ◽

Growth Season ◽

The North ◽

The North Sea ◽

First Year Of Life

Two individuals of thinlip grey mullet Liza ramada were collected in a southern Norwegian brook (58° 22’ N, 8° 37’ E) on 12th September 2007. The fish were 8.7 and 9.0 cm in total length, 6 and 7 g in total mass, and most probably in their first year of life. The nearest known spawning area of the species is south of the English Channel, meaning that they had probably moved at least 900 km across the North Sea during their first growth season. To our knowledge, this is the first published observation of the catadromous thinlip grey mullet from a Scandinavian freshwater course.

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The case for comparison

Rulers, Warriors, Traders, Clerics ◽

10.5871/bacad/9780197264119.003.0001 ◽

2007 ◽

Author(s):

Anne Haour

Keyword(s):

North Sea ◽

Western Europe ◽

North West ◽

The North ◽

The North Sea ◽

North Western

This chapter explains the coverage of this book, which is about the comparison of rulers, warriors, traders, and clerics on the central Sahel and the North Sea region. It argues that there was more similarity between north-western Europe and the central Sahel in the few centuries either side of AD 1001 than has hitherto been recognised, and maintains that the nature of the sources has obscured these formative times and left them in the shadow of organised structures. It discusses the interconnectedness of central Sahel and north-west Europe through contacts and shared pre-industrial nature.

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Investigations Upon the Water Movements in the English Channel. Summer, 1924

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400058410 ◽

1927 ◽

Vol 14 (3) ◽

pp. 685-721 ◽

Cited By ~ 9

Author(s):

J. N. Carruthers

Keyword(s):

North Sea ◽

English Channel ◽

Average Speed ◽

Southern North Sea ◽

The North ◽

Westerly Winds ◽

The North Sea

In July, 1924, 250 floating, and an equal number of bottom-trailing, bottles were put out at selected places in the western English Channel. Fifty of each type were put out at each of the two routine Stations E2 and E3, and the same number was “liberated” at each of three selected stretches along the steamship route from Southampton to St. Malo. Those surface bottles, which did not strand locally, travelled rapidly up Channel towards the North Sea and across it. Many bottles arrived in the Skager-Rack after performing their journey of some 700 miles at the rate of 6 miles a day and more. An adequate study of wind conditions, as recorded at several stations along the length of the Channel and at one station in the southern North Sea, revealed the fact that there was, for some 5½ months (counting from the time of liberation of the bottles), an almost uninterrupted predominance of south-westerly winds—as recorded at all stations considered. The whole area of the Channel was swept by south-westerly winds of average speed of some 9 miles a day for at least 5½ months subsequent to the time of putting out of the bottles. July, 1924, had (according to the Falmouth Observatory records) the largest proportion of westerly winds experienced for 54 years; 20 days of this month had winds with westerly components. The association of the unusually persistent westerly winds with the rapid travel of surface bottles towards and across the North Sea is interesting.

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