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Survey
Work &
Reference Collections
Rocky
Seashore Survey
The Rocky
Shore Monitoring programme was running from Sherkin Island
Marine Station from 1975 until 2015, with 69 sites surveyed
annually on Sherkin Island and the islands of Roaringwater
Bay and in Dunmanus Bay. In 1995 the programme was extended
along the coastline from Bantry Bay to Cork Harbour, increasing
the number of sites to 144.
Sites
were accurately relocated from year to year using maps, photographs
and detailed site directions. A transect line was set out
from the top of the shore down to low water, with quadrats
(0.25m2) placed at vertical distances of 30cm. The mean tidal
range in this area is c.3m, so the 30cm vertical distance
measurement ensured that there were at least 10 stations at
most sites. In practice, this number was variable and dependent
on site conditions. For example, the transect at Cobh Slipway,
Cork Harbour was only 6 stations whilst that of Lord Bandon's
Tower in Dunmanus Bay was 22. Stations along the transect
were set with permanent markings, which ensured that the quadrats
were placed in exactly the same position each year. At each
station the abundance of every species encountered within
the quadrat was recorded and the data entered onto computer.
More than 230 species of flora and fauna were recorded over
the 144 sites.
There
were seven sites on Sherkin Island, which were visited monthly
from April through to October. At these sites two quadrats
were laid down side by side at each station along the transect
line, increasing the survey area.
2003 saw
the publication of "The Ecology
of the Rocky Shores of Sherkin Island - A Twenty-Year Perspective".
It is the first major analysis of rocky shore data from the
programme begun in 1975.
The book
gives well-illustrated background information on the common
species of the rocky shore together with how the rocky shore
food web functions. The main focus of the book are the seven
monthly shores on Sherkin Island. The book was written specifically
to include people and to appeal to a wider audience than the
academic community. For this we are indebted to the author,
Dr. Gillian Bishop, the Station’s first marine biologist in
1975 and now an environmental consultant in Aberdeen, Scotland.
See also:
Distribution Maps
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Phytoplankton
Survey
Phytoplankton
monitoring was the other major programme being carried out
at Sherkin Island Marine Station. Phytoplankton refers to
the microscopic plants found in the sea which form the basis
of the food chain on which most animals depend. From 1978
a team of marine biologists surveyed phytoplankton populations
in the area. Permanent stations were visited every 10 to 12
days from approximately April to November, in Roaringwater
Bay and South of Sherkin, into the open Atlantic up to 12
miles. Water samples were taken at different depths at each
station, down to a depth of 50m. The temperature and salinity
readings were also measured. The water samples were then preserved
and analysed to determine the population densities of each
species. In 1996 we set up a sample station off the Marine
Station landing stage and we did profile sampling every 4
days. Annually we looked at approximately 2,000 water samples
from the 12 sites. Preserved samples are stored in the Station's
archives since 1978.
The most
well known aspects of phytoplankton studies are those relating
to the "Red Tides" that have occurred. Red Tide
is the name given to the phenomenon in which a population
explosion or "bloom" takes place in a phytoplankton
population, usually resulting in the discoloration of the
water, which may be tinged with red (although other colours
can be produced, depending on the pigmentation of the microscopic
plants). The environmental and economic implications of certain
species of phytoplankton have stimulated extensive research
over the years. Some species contain toxins, which can become
concentrated in filter-feeding animals such as mussels. The
serious consequences arise when humans eat contaminated shellfish.
Many species are also responsible for fish kills around the
world. Species of special interest are Karenia mikimotoi
(Gyrodinium aureolum), Dinophysis acuminata
and D. acuta, as they have been responsible for
some of the outbreaks around south-west Ireland.
Ireland's
Marine Institute has its own monitoring and toxicity programmes.
Details of these programmes can be viewed at the www.marine.ie
See also:
Special
on-the-spot Reports on Red Tides
"The
Genus Alexandrium Halim (Dinoflagellata)"
"The
Problems of Toxic Dinoflagellate Blooms in Aquaculture"
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Zooplankton
Survey
Zooplankton
is the name given to the small animals that drift with water
currents in the sea. In 1979, a monitoring project began to
study zooplankton in a manner similar to that of the phytoplankton
monitoring project. A researcher was assigned to the project
each year, with the aim of studying annual population changes.
Sampling took place from the Station's 19' research inflatable
at the same time as the phytoplankton was sampled. The areas
covered were therefore the same as those covered by the phytoplankton
survey. A zooplankton net was used to collect samples as a
vertical haul, representing a column of water at each sampling
station. Once back at the laboratory, identification and assessment
of the species' composition took place using a binocular microscope,
the samples having been preserved in formalin. A single vertical
haul may contain forty or more species, amongst them some
of the more important groups such as Copepods and Chaetognaths.
An extensive reference collection was assembled over the years
and this helped considerably with the identification of uncommon
species.
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Terrestrial
Flora Survey
The wild
plants of West Cork have received less study than they deserve.
Nevertheless there are many hints in the botanical literature
of great richness, notably in the intensive study by Polunin
(1949, 1950) of the islands of Roaringwater bay. Research
on plants by young botanists based at Sherkin Island Marine
Station confirmed this richness.
As a result
of the work carried out at the Marine Station, the islands
of Roaringwater Bay have been recognised as a botanical "hotspots"
for rare plants. Twelve of the species found in the islands
are included in the Irish Red Data Book. And a further two
(Fiddle Dock and Deptford Pink) ought to be included in any
future edition. The Deptford Pink was only discovered in Ireland
as recently as 1992 when Sherkin Island Marine Station botanists
found six plants on Horse Island. It is encouraging to see
that, in 1996, the number had grown to 35.
We found
a total of 627 different flowering plants, conifers and ferns
(including hybrids and subspecies), which is an astonishing
figure for an area of some 10 km2 in Ireland. Indeed, this
would be a high figure for a similar-sized area of Britain,
which has a larger flora than Ireland. The flora of Roaringwater
Bay is thus of immense importance both nationally and internationally.
The area is as rich as anywhere in North-Western Europe.
1996 saw
the publication of "The Wild Plants
of Sherkin, Cape Clear and adjacent Islands of West Cork",
a flora that was the culmination of many years research by
the Marine Station botanists. A supplement to the above flora
was also published in 2011. Rather than marking the end of
botanical studies at Sherkin, the publication of the Flora
only served to fire our enthusiasm for further work. The Sherkin
method of thorough and repeated surveying revealed some astonishing
finds in an area that was hitherto oddly neglected by the
majority of main stream botanists. In 1997 the Station began
a new survey on the islands of Bere, Dursey and Whiddy in
Bantry Bay. The Flora list, when the survey was completed,
surpasses that of the islands of Roaringwater Bay. There is
an herbarium of over 1,000 plants of the Bantry Bay islands
in the Marine Station herbarium.
John Akeroyd,
the noted botanist, oversaw the botanists at the Station,
making annual visits for over 20 years.
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Herbarium
(Flowering Plants and Ferns)
The Sherkin
Island Marine Station Herbarium contains over 2000 specimens
of flowering plants and ferns. Of the 627 species recorded
for the islands of Roaringwater Bay, 531 are represented in
the herbarium - including many of the Roaringwater Bay specialities
such as Lotus subbiflorus (Hairy Bird's-foot Trefoil), Rumex
pulcher (Fiddle Dock), Tuberaria guttata (Spotted Rockrose),
Viola lactea (Pale Dog-violet), Geranium purpureum (Little
Robin) and a magnificent specimen of Babington's Leek (Allium
ampeloprasm var. babingtonii). Of those species that remain
to be collected, five are considered extinct and a further
26 have not been recorded in the islands since the 1950s.
Lucy Wright,
who collected 445 specimens, initiated the plant collection
in 1981-1982. Over the years the collection increased in size
and, in many cases, there are now three specimens of each
species.
In addition
to the flowering plants and ferns, there are also collections
of bryophytes (276 specimens), fungi (109 specimens) and lichens
(100 specimens).
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Bird
Survey
Since
1975 birds were regularly studied at the Station, and detailed
breeding bird surveys of the islands in Roaringwater Bay were
carried out. The geographical position and range of habitats
provides good breeding sites for many types of bird. In addition
the area is important for migratory birds that need food and
shelter, especially when there are adverse weather conditions.
Sea-bird passage along the south coast of Sherkin Island was
monitored and collated with sea birds recorded at sea from
the Station's research boat.
See: Bird
Reports
"Ireland's
Bird Life"
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Otter
Survey
At Sherkin
island Marine Station a continuing research project was set
up to monitor otter, (Lutra lutra L.), activity on Sherkin
itself and on the other islands of Roaringwater Bay. These
included the following islands which were accessed by the
Marine Station's boat:
Ardillaun,
Badger Island, Bird Island, The Calf Islands, Carrigreagh,
The Carthy's, Castle Island, The Catalogues, Clear Island,
Coolim, Goat Island, Little Goat, Goose Island, Heir Island,
Horse Island, Illaunnagrogh, Illaunrahee, Jeremiah's Island,
Long Island, Mannin Island, Quarantine Island, Sandy Island,
Skeam East, Skeam West, Spanish Island, Two Women's Rock.
The first
otter survey of Roaringwater Bay was conducted in 1981.
A new
addition to the project in the mid 1990s was an evaluation
of activity along the banks of the River Ilen Estuary, which
runs from the Mainland into the Bay, NE of Sherkin Island.
The survey
involved traversing the coastlines and mapping tracks and
signs to establish the distribution of areas utilised by otters.
Signs
representing otter activity are:
Spraint
sites - Spots where otters deposit their droppings.
Holt sites
- Otter dens. (These were described and given the status of
'active' or 'non-active' depending on the evidence in and
around the site).
Footprints,
paths or runs, and lie ups (temporary rest sites) were also
noted.
Sightings,
although infrequent, formed an important part of the survey
record.
See: Bulletin
No 12: Otter Survey of Roaringwater Bay, South West Cork,
Ireland, 1990.
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Diving
Survey
The waters
around Sherkin Island are ideal for those people interested
in underwater surveying. The first survey was undertaken in
1975 by Dr. Keith Hiscock et al and various surveys were undertaken
over the year. However due to costs and time, we discontinued
diving surveys in 2001.
See: "Ireland's
Marine Life"
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Sponge
Survey
Two projects
concerning sponges of Roaringwater Bay and adjacent areas
were carried out from 1981 to 1983. A monitoring project was
established to study the life cycle and changes of certain
sponge species. This project was run with the wonderful help
of Miss Shirley Stone - the noted world authority on sponges
- then at the Porifera Section (sponges) of the British Museum
(Natural History). A population survey of all species of sponges
in the area, together with a study of their biology, was also
run during 1982 and 1983. Methods used to survey the sponges
included shore exploration and scuba diving. There is a major
slide collection of sponge skeletons in the Marine Station
archives from the Roaringwater Bay area.
See: "European
Contributions to the Taxonomy of Sponges"
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Rockpool
Survey
Rockpools
are conspicuous components of the rocky shore and have been
reported to contain both a diverse flora and fauna population.
In 1995 Sherkin Island Marine Station began a rockpool survey.
In that
year 48 pools were surveyed on both Sherkin (42 pools) and
East Skeams (6 pools). In all cases the maximum length, width
and depth of the pools were measured. Elevation was recorded
(as the height below the barnacle line) to give a measure
of the position of the pool along the shoreline. Pools were
extensively searched for both flora and fauna species. In
many cases the pools were partially bailed to reach deepest
sections, however this measure was use sparingly to prevent
destructive sampling. A species list of both flora and fauna
was compiled where the former was noted via absence on presence
and the latter, when applicable, via numbers counted.
Since
the basis of the project was to set up a framework for a permanent
study, detailed site descriptions for all pools were prepared.
These included (per pool) a minimum of two photographs, a
map of the pool in its surrounding area and written instructions.
This will ensure that the correct pools can be relocated for
future studies.
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Macrofauna
Survey
Sandy
beaches are the most widely distributed type of intertidal
environments world-wide, but as they appear to be barren and
inhospitable they are the least studied of all intertidal
habitats. The aim of the research at the Sherkin Island Marine
Station was to study a number of diverse sandy beaches for
their macrofauna communities. In total twenty-eight sandy
beaches, from Cork Harbour to Roaringwater Bay, were quantitatively
sampled for their macrofauna populations between June and
mid September 1996 and 1997.
Macrofauna
are living organisms which inhabit beaches and which are retained
by a 0.5mm sieve. This study is an extension of a number of
surveys carried out by undergraduates from 1976-1978 on Sherkin
Island.
Within
Roaringwater Bay, County Cork, Ireland, sixteen beaches were
sampled. Including seven on Sherkin island, three on Heir
Island, two on Horse Island and one on East Calf Island. Beaches
were examined on the uninhabited Islands of East Skeams, Middle
Calf, Catalogues and Carrigreagh.
Along
the Cork Coastline eleven beaches were surveyed, extending
from Baltimore to Cork and including Tragumna, Rosscarbery
Strand, Ownahincha Strand, Summercove, Robert's Cove, Inch
Strand, Myrtleville Bay, Inchydoney, Long Strand and Howes
Strand.
The methodology
employed to sample the beaches involved setting up three line
transects, from high to low water. At 10cm vertical heights
along the transect, 4 replicate 0.01m2 cores to a depth of
15cm were taken. The core samples were sieved on the beach
and any organisms collected were taken back for identification,
with the aid of a microscope and appropriate keys. All new
macrofauna species were fixed and preserved, a full specimen
collection is held at Sherkin Island Marine Station.
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Insect
Survey
As part
of a number of surveys of the insects of Sherkin Island and
the other islands of Roaringwater Bay, insects from the following
insect groups were collected and identified:
Hymenoptera
(bees, ants and wasps)
Neuroptera
(lacewings, alderflies, snakeflies & antlions)
Dermaptera
(earwigs)
Orthoptera
(grasshoppers and crickets)
Coleoptera
(beetles) See: Beetles Survey
Heteroptera
(bugs)
All specimens
are in the Station's archives.
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Beetle
Survey
Coleoptera
(Beetles) surveys was undertaken for 1980, 1981, 1991, 1992
1993 and 1995 on some islands in Roaringwater Bay. Sherkin
Island was the main island surveyed. The list for all the
islands now stands at 537 species. The collection of the beetles
took place between May and September and involved sweep-netting,
hand collection and pit-falling. All specimens are stored
in the Marine Station archives.
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Butterflies
& Moths
Lepidoptera
work was carried out at Sherkin Island Marine Station in the
following years: 1977, 1978, 1981-1983, 1985, 1986, 1991,
1992, 1996-2001, 2004 and 2005. This work makes Sherkin Island
one of the most intensively studied places in Ireland for
Lepidoptera. In 1997 a small number of sites were chosen for
moth trapping (four besides the Marine Station). These sites
were sampled intensively in order to try and catch a large
proportion of the moths that fly in these areas. Butterfly
transects were established in 1997 and were continued in 1998,
1999, 2001, 2004 and 2005.
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Seaweed
Collection
There
is an extensive collection of over 2,500 seaweed specimens
in the Seaweed Herbarium.
Seal
Survey
A survey
of the Grey Seal population was carried out during 1985 to
monitor possible changes since a 1981 survey. There are several
sites around the bay in which seals may be observed hauled
out on the rocks.
Flatfish
Survey
Sherkin
Island contains a number of areas important to flatfish as
"nurseries". These are regions where the growth
and survival of juvenile fish are enhanced due to less risk
of predation, more amenable temperatures and a more readily
available food source. A number of surveys were conducted
by the station since 1980 and were concentrated on one such
nursery, Kinish Harbour.
This site
was fished regularly by beach seine between the months of
June and September.
The flatfish
populations were shown to change over time, with less fish
being caught within Kinish Harbour towards the end of the
summer.
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Reference
Collection
The Sherkin
Island Marine Station Reference Collection consists of:
Plant
& Fern Herbarium:
Roaringwater
Bay and the islands
Bantry
Bay - Bere Island, Dursey Island and Whiddy Island
Seaweed
Herbarium - including slide collection
Sponge
Skeleton Slide Collection
Specimens
of Marine Animals:
Over
3,500 preserved specimens of marine animals from mainly
the Roaringwater Bay area - Sherkin Island and the Islands.
Otter
Spraints.
Insect
Collection:
Includes:
Beetles, flies, dragonflies, moths and butterflies, aquatic
bugs.
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Photographic
Collection
Over 4,000
colour slides on the natural history of Roaringwater Bay.
Littoral
and sub-littoral in the main, taken by Paul Kay and Pete Atkinson,
former Sherkin Island Marine Station biologists. Both are
now international natural history photographers. See: "Ireland's
Marine Life"
Over 2,500
black and white photographs of ruins/buildings/sea shores
of Roaringwater Bay.
This major
collection was taken on the various islands of Roaringwater
Bay by Paul Kay and Ian Watts during 1981 and 1982.
Collection
of phytoplankton photographs of many of the species identified
in the area.
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Meteorological
Records
Sherkin
Island Marine Station has, since July 1972, kept daily rainfall
records and from August 1974 sunshine and temperature records.
The station is the lowest (latitude-wise) in Ireland. The
records are sent monthly to the Irish Meteorological Office
(Met Eireann) in Dublin. We are one of a select number of
stations whose records are used in the IMO monthly bulletin.
See: No
5: Rainfall of Sherkin Island 1973-1984
No
10: Sunshine Records of Sherkin Island 1974-1984
No
11: Air Temperatures of Sherkin Island 1975-1984
No
14: Air Temperatures of Sherkin Island 1985-1989
In 2000
Met Éireann embarked upon the TUCSON programme of Automatic
Weather Stations (AWS’s). TUCSON stands for The Unified
Climatological and Synoptic Observational Network. Given its
location and the amount of the south coast not covered, Sherkin
Island was chosen as an ideal location for an AWS. The station
was commissioned on the 28th of April 2004.
The station
measures:
Temperature:
Air, Grass, Soil – 5cm,10cm,20cm, Earth – 30cm,
50cm, 100cm
Rainfall:
0.1mm & 0.2mm gauges
Solar
radiation
Wind
speed & direction
Atmospheric
Pressure
Relative
Humidity
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Station 2021
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