By-the-wind
Sailors,
Velella
velella
and Violet Sea Snails,
Janthina
20
December 2014
A
huge wreck of jellyfish and pelagic jellyfish-like
animals occurred on the north coast of Cornwall with tens of thousands
of By-the-wind Sailors,
Velella
velella,
washed ashore on various shores, and a thousand plus Mauve
Stinger Jellyfish, Pelagia
noctiluca, at Sennen
Cove, Watergate
Bay
and Fistral Beach
(Newquay). The stranding
also included thousands
of Goose Barnacles,
Lepas
anatifera.
24-25
May 2009
There
were some By-the-Wind Sailors, Velella
velella,
washed up this weekend at Hell's
Mouth, Lleyn
Peninsula, Wales. They were probably more like 30 mm in diameter.
20
May 2009
Several
thousand By-the-Wind Sailors, Velella
velella,
were spotted amongst the Devonshire rock pools
at around 6:00 pm
on mid tide. All appeared dead with no signs of
movement in the body/tentacle
Location
- Between Stoke Point and Netton island SX 555E 459N
due south of Newton Ferrers.
Colours
- Blue/Black/Clear
Size
- two groups - from 4 to 6mm, and 10 up to 15mm
The
sail directions - North-West to South-East
Further reports have arrived from Cornish beaches including Par Beach near St. Austell, and Kynance Cove.
18 May 2009The specimens are very small, only a few millimetres in length. More Velella arrived on each tide.
4
January 2007
Both
species of Violet Sea Snail, three
Janthina
janthina and one Janthina
pallida were discovered on the beach at
Perranporth, Cornwall, (SW 75).
2
January 2007
At
Gwithian beach, Cornwall, (SW
54), 15 Violet
Sea Snails,
Janthina, were discovered
on the strandline.
30
December 2006
I
managed to find a Violet Sea Snail,
Janthina
janthina, amongst the By-the-Wind Sailors
at
last on South Milton beach, it has taken me nearly twenty years of looking
south Devon beaches to find this delightful gastropod
mollusc!
26
December 2006
I
fulfilled a life-long ambition to find a Violet
Sea Snail at Perranporth, south Cornwall,
where we discovered 14 Janthina janthina
and 7 Janthina pallida
between us. I was surprised to find Janthina
pallida as I was previously unaware that
they reached our shores.
20
December 2006
Three Violet Sea Snails, Janthina, were discovered on Marazion beach in south Cornwall.
17
December 2006
Twenty
Violet
Sea Snails,
Janthina, were discovered
along the beach at Woolacombe,
North Devon. Most were about 10 mm in size, and some were still alive with
their bubble rafts and "inked" when placed in a bucket. They were
washed in with tiny (max 12 mm) By-the-Wind Sailors, Velella
velella, Buoy Barnacles,
Dosima
fascicularis, and a small 15 cm Triggerfish,
Balistes
capriscus.
14
December 2006
At
Sennen,
Cornwall, two species of Violet Sea-snails,
Janthina
janthina and Janthina
pallida,
as well as two sea beans Entada
gigas and Caesalpina
bondoc were discovered on the strandline.
11
December 2006
By-the-wind
Sailors,
Velella velella, were found washed up on Blackpool beach, Lancashire.
7
December 2006
Two
seperate reports were received of hundreds of Velella velella from
Aberdovey in Wales. There are also the first reports of a few from the
Sussex coast.
Pleuston
17
November to 3 December 2006
Reports
of Velella velella have come in from the Isle of Skye (furthest
north) to Hengistbury
Head in Dorset (furthest east up the English Channel).
|
Velella
on on Eastern Green, between Penzance and Long
Rock, Cornwall
Photographs
by Paul Semmens
4 December
2006
Even
more Velella velella are coming in. On the shores of Cardigan
Bay, Wales, there are millions in the sea and they will become stranded
on the shore when the tide recedes.
29
November 2006
We
found numerous Velella velella on the beach at Hengistbury
Head (Grid ref: SZ 174906)
in Dorset. We had never seen them before (despite a lot of walking on beaches).
They were many different sizes (3-12 cm), most blue edged, occasionally
transparent.
Thousands of By-the-wind Sailors, Velella velella, were washed up on Welsh beaches, notably a narrow but continuous line of Velella velella washed up on the high tide mark at Borthwen, Rhoscolyn, Anglesey (southern end of Ynys Cybi - Holy Island), north Wales (Ian Wright); literally thousands stranded on a small bay at the Mumbles, Swansea (Jess Pitman); a swarm amounting to about two hundred were washed up on Porthllysgi beach off the coast of St. Davids in south west Wales (Eleri Davies) with hundreds, possibly thousands, stranded and dead on the pebbles on the nearby Newgale Beach (Helen Lee); thousands, if not millions, of By-the-wind Sailors washed up on a beach at Criccieth (on the southern coast of the Lleyn Peninsula), Gwynedd, north Wales (Eilir Daniels); and an armada, a thick layer of jellyfish about a metre thick on the strandline in both directions at Cefn Sidan Beach at Pembrey, south west Wales (Bella).
There were By-the-wind Sailors, Velella velella, at Constantine on the North Cornwall coast. They were mentioned to me by someone that had seen them and they were 'in the hundreds' and were already transparent.
We
(Devon Wildlife Trust)
had a report of thousands of By-the-wind Sailors, Velella velella,
on Saunton
Sands,
north Devon. These were probably the same as those washed in previously
except a number of Goose Barnacles
were also noted attached to flotsam and jetsam amongst them. All
of these beaches face west.
19
November 2006
A
large number, probably several hundred, of By-the-wind Sailors,
Velella
velella, were washed up on beach at Newborough,
on the southern cost of the Isle of Anglesey, north Wales.
Multipmap
Location
2
November 2006
After
a period of warm southerly and south-westerly winds, the weather changed.
Strong colder winds came from the north-east and an easterly direction.
By-the-wind
Sailors, Velella velella, entered St. Peter Port harbour on
Guernsey's east coast, driven in by the wind. Commercial fisherman
Clive
Brown called to tell me that about 25 Velella
velella were washed up on the shore near his dinghy in the harbour.
I went down to the Albert marina and I was able to collect four Velella
velella by reaching out from a pontoon. This
picture shows one of them mirrored by the water's surface:
Velella
Report
& Photograph by Richard
Lord (Guernsey)
Sea
Lord Photography
31
October 2006
Tens
of thousands of By-the-wind Sailors,
Velella
velella, were wrapped up in the Thongweedand
Zostera
Eelgrass
on Porth Hellick Beach, St. Mary's, Isles of Scilly.
|
I heard they had also come ashore on other beaches on the east of the island. They were still quite fresh, though dead.
25
October 2006
I
was approximately 5 to 6 miles west of the Casquettes, off Alderney, Channel
Islands, and I saw about ten Velella velella being blown
past our boat in a few minutes.
|
|
|
Photograph by Jonathan Smith |
Photograph by Jonathan Smith |
Some Reports:
24
September 2004
Thousands
of Velella
were washed up at Woolacombe, north Devon in unprecedented numbers, estimated
up to 200 a square metre!
At
Westwood Ho!, north Devon Velella
are two or three inches (50 - 75 mm) thick on the shore.
c.18
September 2004
Several
hundred By-the-wind Sailors arrived
on the beach on the Isle of Islay, west Scotland. The flesh rotted away
quite quickly.
16
September 2004
Velella
were
found on the shore between Newquay in Wales and Aberaeron with a
length of 60 mm +. There was one every three metres or so around the rocks
at Cei Bach thinning out in the sand areas. All were strikingly large compared
to those I have found before in south Wales and Cornwall before. All had
soft tissue and colour but were dead and disintegrating.
Velella
on Constantine Bay beach, north Cornwall
Photograph
by Amanda
Bertuchi
A huge mass stranding of By-the-wind Sailors, Velella velella, occurred all along the north Cornish coast from Sennen Cove (near land's End) up to Polzeath (near Padstow) and beyond. (As the gull flies this is a distance of 25+ miles and with all the coves and inlets the shoreline is over double this.) Coming in on the top of the tide, there were hundreds of millions* of them, all large, the largest I found was 85 mm, and all them were intact. Millions of Barnacles were washed up along the strandline.
(* Numbers not calculated. At Gwithian they formed a band 10 metres wide on the shore and stretching for over a mile. The above photograph understates the extent of the stranding.)
The
Buoy
Barnacles,
Lepas fascicularis,started
coming in on the same tide as the Velella.
I've seen with my own eyes on Porthcothan (SW
8572), Treyarnon and Constantine and Paul
Gainey saw them on Gwithian, all in north
Cornwall. I'd be very surprised if they weren't all the way up the coast
and I'd number them in millions, all big. The Goose
Barnacles,
Lepas,are occurring
in their usual quantity for this time of the year, if anything, less. To
give you an idea, on my beach, Pothcothan, 25 acres at low tide:
Velella
approximately one million, Buoy Barnacles:
2000+, Goose Barnacle
colonies: 7.
At
least one Portuguese Man o'War, Physalia physalis, was also
washed up and there were undoubtably more.
The
Buoy
Barnacles
were attached to floats that
they had secreted that had a texture like that expanding foam.
BMLSS
Strandlining
BMLSS
Barnacles
4 June
2003
We
have got loads of By-the-Wind Sailors,
Velella
velella, in the Fowey estuary, Cornwall, as far up as Wisemans
reach. They are coming in by the bucket load. Lots were stranded on Readymoney
beach and there were lots washing in the night. I haven't seen any Violet
Sea Snails, but am going out on the water
this morning so shall look out.
4
June 2003
I
was on Charmouth beach in Dorset doing a little fossil hunting and suddenly
found myself lying (best way to find tiny crinoids etc) in a wreck of tiny
jellyfish. They had a bizarre transparent float and were a vivid blue being
only around 25 to 30 mm long. These are By-the-Wind
Sailors,
Velella
velella.
26
May 2003
Hundreds
of By-the-Wind Sailors seen
approximately half a mile SE of Guernsey, Channel Islands in the afternoon.
24
May 2003
Polurrian
Beach, Mullion, Cornwall: I found hundreds of By-the-Wind
Sailors,
Velella velella, on the
falling tide on Saturday and by the smell/remains they have been coming
ashore for several days.
21
May 2003
Ray
Lawman has reported to Ruth
Williams that he there were about half a million
Velella
velella at "Soapy Cove" on the Lizard, Cornwall.
Thousands of tiny By-the-Wind
Sailors,
Velella velella, are coming
ashore on the Isles of Scilly . Porthlow on St. Mary's (Porthloo on maps)
was covered with them, most only about 10 mm in length with only the occasional
larger one, and the larger ones were very large at approx. 50 mm, with
none in-between. I don't think I have seen them either as big or as small
before.
20
May 2003
Hundreds
of
By-the-Wind Sailors,
Velella
velella, (a jellyfish-like animal) are washed up on Sennen
Cove, Cornwall.
Sennen
Cove Wildlife Page
By-the-Wind
Sailors,
Velella
velella, are being reported again in the sea and washed up on the
strandline on the north Cornish shores and Salcombe Harbour, south Devon.
By 1 February 2003 the westerlies have blown plenty of By-the-Wind Sailor, Velella velella, and the Mauve Stinger, Pelagia noctiluca, on to Sennen Cove, Cornwall, above the high tide mark.
28
January 2003
Thousands
of By-the-Wind Sailor,
Velella
velella, are discovered washed up, alive or very freshly dead, on Perranporth
Beach, Cornwall, together with the Violet
Snail, Janthina janthina, (two
shells) that preys on Velella. This gastropod
is rarely recorded in British seas even when there are large numbers of
Velella
stranded. It is always worth looking for this attractive and fragile shell.
Rory Goodall has also found large numbers of Velella on Porthmeor Beach, St Ives, Cornwall.
15
November 2002
After
the recent gales, further large numbers of freshly dead Velella
are washed up on the Dorset (Studland) coast with over 50 counted in a
stretch of strandline of 100 metres. The dead Velella were still
coloured blue which showed that that they have only recently died. They
disintegrate and turn white over night. There were live specimens at five
miles off the Dorset coast.
13
June 2002 found thousands of Velella
were washing in on Kilmory Bay, Sound of Jura, Argyll, Scotland. There
was a lot of foam along the tideline at the time and they were quite fresh.
This is a south-west facing bay inshore of Islay and Jura in the western
islands and the furthest north record for 2002.
9
June 2002
Large
numbers of dead Velella along strandline of sandy beach at Kilmore
Quay (SE Ireland). Estimated to be in excess of 300 Velella
per metre of strandline for about 50 metres (= 15000). They were
a bit dried out so must have been there for a few days.
15
November 2002
After
the recent gales, further large numbers of freshly dead Velella
are washed up on the Dorset (Studland) coast with over 50 counted in a
stretch of strandline of 100 metres. The dead
Velella were still
coloured blue which showed that that they only recently dead. They disintegrate
and turn white over night. There were live specimens at five miles off
the Dorset coast.
6
December 2001
Report
from Mr David Leggat.
Cadgwith
Cove, the Lizard, Cornwall. Large (hundreds probably) numbers of
the hydrozoans, By-the-wind Sailors Velella velella, between 2 and
7 cm in diameter washed up on this east facing shore.
October
1999
Tens
of thousands By-the-Wind Sailor, Velella
velella, were discovered by Paul
Gainey, washed
up on the between Gwithian and Mexico Beach beaches on the north coast
of Cornwall. They were also reported at Sennen Cove (near Land's End) by
Jayne Herbert. In December
1999, hundreds
were reported by Chris Stumbles on a Cornish shore.
Photograph by Richard Lord
9 October
1999
High
up on Saline Beach near the slipway I found a By-the-wind sailor, Velella
velella, in good condition. The pelagic colonial hydroid had
most of its tentacles and was a vivid blue colour. Richard
Lord (Guernsey).
Underside
of Velella
Photograph
by Richard Lord
January
1998
Jon
Makeham also discovered about 500 washed up Velella at Looe,
southern Cornwall. This is a lesser number than in previous years.
There
are more records of stranded Velella in the BMLSS archives (before
1996 when computer records were collated for the web site entries). Notably,
mass strandings in 1992, reported by Amanda Young (Anglesey).
Rhizostoma
pulmo
News Report 1999
Norwegian
Marine ***
These web pages are recommended
for photographs of Jellyfish
dear
Richard
Velella
velella is a hydroid more common in subtropical to tropical off-shore waters.
Strandings are
thus
accidents. The sail is made of a chitinous substance and is homologous
to the periderm of
"ordinary"
hydroids. Velella is actually a polyp colony turned upside down and
the hydranths are
underneath
the float. They are differentiated into three main forms, functioning as
tentacle-like
food
capturing individuals at the rim, as a central polyp that digests the food,
and as gonozooids
that
produce tiny medusae.
The
colony releases numerous medusae, but mature ones have only rarely been
found in the plankton.
The
full life cycle of Velella is not known, as the earliest developmental
stages presumably take
place
in depths of below 1000 m. It is thus not known whether there is a planuLarva
in the cycle.
The
earliest stages (conaria, ratiaria) are already comparable to small colonies.
These stages
produce
oil droplets which render them floating and they thus ascend to the surface.
Mature
Velella's exist in two form, the left and right sailing forms. There are
several papers
examining
this dimorphism. It is thought that the prevailing winds can indeed sort
out the two
forms,
so that depending on the major wind direction you will find stranded animals
that are either
predominatly
left or right sailing forms.
For further information I suggest using one of the following publications:
Kirkpatrick,
P. A., & P. R. Pugh 1984. Siphonophores and velellids.
Synopses of the British Fauna (New Series) 29: 1-154.
Brinckmann-Voss,
A. 1970. Anthomedusae/Athecata (Hydrozoa,
Cnidaria) of the Mediterranean. Part I. Capitata.
Fauna e Flora Golfo di Napoli 39: 1-96, pls 1-11.
more
details are e. g. found in:
Bieri,
R. 1959. Dimorphism and size distribution in Velella and Physalia.
Nature, Lond 184: 1333-1334.
Bieri,
R. 1977. A morphometric study of Velella (Hydrozoa) from
different oceans. - Publs Seto mar. biol. Lab. 24: 59-62.
Francis,
L. 1991. Sailing downwind: aerodynamic performance
of the Velella sail. - Journal of Experimental Biology 158: 117-132.
Savilov,
A. I. 1961. The distribution of the ecological forms of the
by-the-wind sailor VelelLata Ch. and Eys., and the P
ortuguese man-of-war Physalia utriculus (La-Martinière) Esch.,
in the North Pacific. - Trudy Inst. Okeanol. 45: 223-239.
kind
regards,
Peter
_____________________________________________
Peter
Schuchert
Museum
d'Histoire Naturelle
1
Route Malagnou
CH-1208
Geneva
Switzerland
Taxonomy of Hydrozoa
my
hydrozoa site (new portraits added 22.10.2001)
http://www.geocities.com/peterschuchert/Hydrozoa.htm
_____________________________________________
> Has anybody got an information
source on the reproduction of
Velella please?
The complete life cycle of
Velella, which includes a tiny medusa, is not
entirely known. The mature
medusa has been found in nature only once or
twice and the earliest stages
of the life cycle, meaning fertilisation and
early development to the
so called conaria larva, are unknown. They likely
take place in deep waters,
despite the medusa having symbiontic algae.
For a good résumé
see:
Brinckmann-Voss A. 1970.Anthomedusae/Athecatae
(Hydrozoa, Cnidaria) of the
Mediterranean. Part I Capitata.
Fauna e Flora del Golfo di Napoli vol. 39,
pp. 1-96, 11 pls.
kind regards,
Peter Schuchbert
Peter.Schuchert@mhn.ville-ge.ch
<Peter.Schuchert@mhn.ville-ge.ch>
_______________________________________________
List-Info:
https://maillists.uci.edu/mailman/listinfo/cnidaria
I fished one out of Kimmeridge Bay, Dorset, in a cup last year (2003) - it then deposited hundreds of tiny medusae into the cup. I suppose they had no intention of sailing to England and would normally reproduce in mid ocean
It was reported by Prof Walter Garstang (1946), and there is an account in Sir Alister Hardy's classic book The Open Sea, Book I The World of Plankton; Chapter 7 pp 110 to 113.
I find it a bit confusing but I read it as that what we are seeing are the asexual stage, they release sexual medusae (what Peter saw) and the offspring of these (planulae larvae) are called Conaria. These sink into a deep water mass, which is likely to be moving in a different direction to the surface water where the medusae and asexual forms are. This will disperse them. When the float zooid develops they rise to the surface and then the individuals with a left twist are dispersed by the wind in one direction and those with a right twist on the different course.
regards, Doug Herdson
Cnidarian
Page (with jellyfish-like animals)
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