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Lauren Clegg
Differences in Behaviour of Halichoerus grypus at Two Sites in Cornwall
Lauren Clegg
FdSc Marine Science, Cornwall College, Falmouth Marine School, Falmouth TR11 3QS
This study investigated the ethology of Halichoerus grypus at two similar tidal offshore haul outs,
with the main difference of exposure to disturbance. The study was to compare the behaviour of
Halichoerus grypus at each site, to conclude whether a higher exposure to disturbance will cause a
difference in behaviour. Land based surveys took place over a six week period, finally gathering 48
hours of observational data. More seals were recorded at Gwennap Head; therefore more varying
behaviours were recorded. Although the data did not deem sufficient enough statistically, the
Halichoerus grypus surveyed within the Fal, have not yet been recorded for behavioural interest.
Therefore this study is a baseline study to be continued by Falmouth Marine School students,
hopefully over many years to come. These studies can aid the spread of knowledge and continuous
protection of Grey seals around the Cornish coast.
Key words: ethology, Halichoerus grypus, haul out, disturbance, behaviour.
___________________________________________________________________________
INTRODUCTION
Halichoerus grypus are the most abundant of
carnivorous marine mammal sighted in the
South West of England. (Leeney et al. 2010)
The UK coastline is home to approximately
45% of the total worldwide population (Ibid)
with a small percentage of the population of
Great Britain living in numerous colonies
around the Cornish coasts. (Summers, 1974)
An estimation of 0.5% of the worldwide
Halichoerus grypus population can be found
around the Coast of Cornwall and the Isles of
Scilly. Pup census are undertaken to estimate
the annual population increase around the
Cornish coastline. (CSG, 2010) Common seals,
Phoca vitulina are rare around the South West
of England, but have been known to visit the
Cornish Coasts. (CSG, 2009)
Grey seals in the South West UK usually haul
out on rocky outcrops or sandy beaches in
groups, usually lying fairly close together.
(SMRU, 2010) Haul outs are used by seals as
areas to rest, moult, digest their recent meal,
mate and give birth. (Lewis, 2006)
Grey seals, Halichoerus grypus are a highly protected species, (Strong et al. 2005) having once been listed as threatened due to over exploitation; however, fortunately the Grey seals are no longer threatened. (IUCN Redlist, 2010) Halichoerus grypus are protected under the Protection of Seals act 1970 and the European Union’s Habitats Directive (Council of the European Communities, 1992) however there are still many threats towards Grey seals in this region. (Leeney et al. 2010) Areas around the Cornish coast that are Sites
of Special Scientific Interest (SSSIs) and Special
Areas of Conservation (SACs) where Grey
seals are found are usually designated due to
the presence of Halichoerus grypus. (Kiely et
al., 2000) Where Halichoerus grypus are listed
as a feature within an Site of Special Scientific
Lauren Clegg
Interest, protection of the creatures is held
through the Wildlife and Countryside Act.
Grey seals are also protected under Annex II
and Annex V of the EC Habitats Directive 1992
(NE, 2010) and Appendix III species under the
Bern convention (WiSe, 2008)
Human and seal interaction includes the
threat of net entanglement. Seals are
naturally very curious creatures and have
been seen to approach and play with drift
nets, which can cause them to become
entangled. (L.C. Personal observation)
Habitat loss, pollution (marine litter) and
culling by fishermen are additional threats to
Grey seals on the Cornish coast. (Leeney et al.
2010) Conflicts between the fishermen and
the seals due to decreasing fish stocks are
posing a continuous threat to the seals
around Cornwall and the rest of the UK. (Ibid)
Although Grey seals are protected, the
Conservation of Seals Act 1970 states that it is
still legal for a seal to be shot under license if
it is seen to be causing damage to fishing net
or tackle or taking of fish from within the net,
providing the seal is within the vicinity of net
at time of shooting. (Kiely et al., 2000)
The study of animal behaviour is known as
Ethology. Since the 1980s, practical ethology
has developed the ability to accommodate
what is known as the normal behaviour of a
species and be able to specify the abnormal
behaviours. (Gonyou, 1994) Abnormal
behavioural changes can be used to indicate
reduced welfare or stress of the animal, which
in turn indicates a factor of this abnormal
behaviour which can then be looked into and
potentially reduced. (Ibid)
Behaviour and sightings of seals at haul out
zones can be due to a variety of factors
including time of year, (Sayer, Pers comms.)
time of day, tidal cycles, weather and sea
state. (Leeney et al. 2010) Human disturbance
can also be a factor of behavioural changes of
Grey seals at haul out sites. (CSG, 2011)
This study documents the behavioural
comparison of Grey seals at two haul out sites
in Cornwall.
METHODS AND MATERIALS
Study areas
Site one, Gwennap Head, lies on the most
south-westerly coastal tip of England in
Cornwall. Gwennap Head cliffs are exposed to
the deep sea south-westerly swell (Fleming,
1995) of the Atlantic Ocean. Gwennap Head is
one of the best seawatching sites in England
(Walker & Wilson, 2007) with a tidal haul out
zone used primarily by a local colony of Grey
Seals.
SeaWatch SW Annual Report 2009 states that
the numbers of Grey seal seen at the haul out
at Gwennap Head remain stable, with a
maximum of 20 Grey seals seen at one time
on more than one occasion using the haul out
site.
Human Activities occurring at Gwennap Head
that could disturb the seals include crab and
lobster potting, local fishing boats working in
the area, commercial tour boats, and
watersports including kayaking and
recreational yachting and people walking
along the cliff top. (L.C. Personal observation)
Any disturbance including human activity
plays a large part in the behavioural changes
of marine mammals, including the Grey seals.
Venables, 2008 states that the haul out at
Gwennap Head is a “regularly used low tide
haul-out, often disturbed by boats passing
between the haul out and the mainland. Once
disturbed the Grey seals Halichoerus grypus
often don't return that tide.”
The second site is located within the Fal
estuary. The Fal is the third natural deepest
harbour in the world, after Rio de Janeiro and
Sydney. The Carrick Roads is 4 miles up the
estuary from where Black Rock is located (PoT
Lauren Clegg
& FHC, 2001) within the middle of the
entrance of the Fal Estuary, on the South
coast of Cornwall. Black Rock is a dark cone
shaped beacon set on rocks, with two spheres
located on top of its conical structure. (L.C.
Personal Observation)
Black Rock is a haul out area for a much
smaller colony of Halichoerus grypus than at
Gwennap head; this haul out is visible at low
tides and submerged by water at high tide.
(Ibid)
Human Activities occurring around Black Rock,
Fal include watersports; scuba diving,
powerboating, kayaking, sailing etc.,
recreational and commercial fishing,
commercial tour boats (ORCA sea safaris) (L.C.
Personal observation)
Factors affecting Halichoerus grypus
behaviour
A variety of factors including time of year,
time of day, tidal cycles, weather and sea
state can cause a change in behaviour of
Halichoerus grypus. (Sayer, Pers comms, 2011;
Leeney et al. 2010) Human disturbance can
also be a factor of behavioural changes of
Grey seals at haul out sites. (CSG, 2011)
Human disturbance can occur from land and
also closer to the seals at sea, for example by
boat and watersports activities.
Disturbance can be minimised by land based
surveyors remaining quiet whilst surveying
and if a seal notices them, for them to stay
still and not pose any threat. (CSG, 2011) Boat
based surveying can be controlled with a
complete understanding of the marine
mammal code of conduct. (WiSe, 2010)
Data collection
Scientific research today, including
behavioural studies, tend to take place in
laboratories in a controlled environment.
However, to understand behaviour at its most
normal is in the natural environmental
surroundings, with most of behavioural
studies taking place in the wild. (Bramwell
Slater, 1999)
Through the method of practical ethology,
ethograms are used to record the variety of
behaviours that the seals may express
throughout survey times. An ethogram is
defined as a list of species behaviours and
actions that define them. (Smithsonian, 2010)
Over a six week period, from 11/03/11 to
27/04/11, observations for Grey seal
behaviour took place; twenty four
observations overall.
Black Rock haul out was observed from
Pendennis Point, Falmouth and the haul out
at Gwennap head was surveyed from the cliff
tops, beneath the coastguard station.
Twelve land based surveys took place at
Gwennap Head with nine land based surveys
at Pendennis Point; with three extra surveys
being boat based within the Fal.
At each survey, the tide times and height
(neap and spring), weather and sea state were
recorded; primarily to investigate whether the
sea state had any effect on the behaviour of
Halichoerus grypus. Tidal state was
determined using the Mylor Yacht Harbour
Tide Time Table 2011. The sea state was
recorded using the Beaufort scale as
guideline.
Observations were made during a two hour
period starting one hour before and
concluding one hour after the low tide time.
The time of day of each survey differ due to
varying ebbing tidal times.
The number of seals and their behaviours
were recorded using an ethogram,
throughout the two hour period, to enhance
the chance of seeing the seals behaviours
change, such as movement from sea to land
or vice versa, rather than surveying at set
intervals.
Lauren Clegg
Adler 10x42 binoculars were used for
observations, with all photographs of various
behaviours taken with a Canon 450D digital
SLR camera with 70-300mm zoom lens. Any
extra zoom or lighting adjustments required
was altered with Microsoft Office Picture
Manager.
RESULTS
Black Rock results were minimal, having only
observed four Halichoerus grypus over the
twelve, two hour surveys.
Black Rock haul out Grey seal visitors did not
act distressed by human disturbance; main
disturbance from boats, slowing down to look
at the seals. All seals at Black Rock were
surveyed as mostly lying with heads down, as
if sleeping, or scanning the area around them,
if disturbed, as if curious to what activity was
happening around them; perhaps ensuring
their safety.
One survey included sightings of a pod of up
to twenty Bottlenose dolphins, swimming
around Black Rock and into the bay; this did
not distract the one seal surveyed that day to
cause a change in behaviour.
Black Rock is situated in a much more
sheltered position than the haul out at
Gwennap Head.
Gwennap Head haul out provided a few more
sightings, with much more behavioural
activity within the water. From personal
observation, higher sea states resulted in no
sightings or sightings for a very short period of
time.
The concluded t value of 0.73 has caused a
rejection in the certainty of the two haul out
sites being comparable of Halichoerus grypus
behaviour.
Concluded factors affecting haul out
behaviour include disturbance; both human
and marine, sea state and tidal state.
DISCUSSION
This study is a vague baseline study for all
flourishing future studies on the behaviour of
Halichoerus grypus within the Fal estuary in
comparison with other haul out zones in
Cornwall.
The paired t-test was used to statistically
analyse any comparison of behaviours
between the two haul out zones, as the study
of behaviour has been measured with the
study occurring in a natural pair, due to study
of same species: Halichoerus grypus.
Due to minimal results gained from Black
Rock, a comparison between the behaviours
of the two haul outs could not be made.
However, the tidal effects, such as neap and
spring tides, had a slight effect on the
appearance of the Halichoerus grypus at the
Gwennap Head haul out.
The Halichoerus grypus did not show much
movement at Black Rock, most lying as if
sleeping or scanning when disturbed to see
what was happening around them.
Whilst studying wild animals, there is no
certainty that the animals will be where you
want them at the time you wish to survey
them. Primarily, the behaviour of wild
animals, such as Halichoerus grypus, may be
disturbed by the surveyor’s presence, which
may become eased over time. To prevent any
disturbance from the beginning, the land
based surveys are better, due to distance and
inability to get over to the haul out zones.
Also, land based surveying methods are low in
cost, it is easy to return to the same/similar
area of previous observation, however the
observer is restricted to the vicinity of which
you can only immediately see. (Evans &
Hammond, 2004) Marine mammals in general
are easier to locate on days of calm weather
and seas. (WDCS, 2010)
Boat based surveying methods can help with
Lauren Clegg
repeat observations; however, the observer
does not have any control as to where the
boat is travelling, which may not be the same
as previous observations. (Ibid)
The three boat based surveys that took place
in the Fal, allowed the observer to see if any
Halichoerus grypus were hauled out on the
side of Black Rock that is not visible from
Pendennis Point, due to the conical “nautical
marker” structure on the rocks.
Any boats causing any kind of disturbance
were noted to be far enough away as to
comply with the WiSe marine mammal code
of conduct.
“Peak ebb and flood tide times were defined as three hours after and before high water, respectively.” (Leeney, 2010) This would come in handy for future surveys. The two hour surveys collected some behavioural data, however, if observations were taken over a
longer period of time, those seals that were already hauled out can be seen at the point of when they hauled out, which could also define peak haul out times before the lowest tide of the day. More behaviours may also be recorded if watched over a longer period of time. The time of year of studying Halichoerus grypus certainly needs to be considered. Personal communication with Sue Sayer of Cornwall Seal Group, whom has been studying Halichoerus grypus for over ten years, commented that the time of year that this survey has taken place, would not provide sufficient data due to little sightings. However, continuous data collection for varying times during the year can decipher the time of year that Halichoerus grypus use the haul out within the Fal most. The total time of this survey was 48hours, for future observations, this number need to be increased considerably to gain the results required to be able to reject a null hypothesis. Further previous data could potentially be obtained from the Cornwall Seal Group for Halichoerus grypus haul out site at Gwennap head as this area has been studied previously and current data can be compared to previous data collections. Personal input into the idea of purchasing a web cam to be placed on Black Rock will ease the surveying for those continuing the study of Halichoerus grypus in the Fal. I cannot stress enough how much personal communication with Sue Sayer of Cornwall Seal Group will help in every way with this
project. This study did not obtain enough personal communication with Sue Sayer and has therefore suffered because of this.
ACKNOWLEDGEMENTS
The author would like to acknowledge the
acquaintance and funding from Falmouth
Marine School and Falmouth Harbour
Commissioners.
Sue Sayer, Cornwall Seal group has been a
huge aid with Halichoerus grypus expertise
through personal communication and
knowledge found on the Cornwall seal group
website for input of different seal behaviours
and building of personal ethograms for this
survey; behaviours were continuously added
to the ethograms over the surveying period.
Thank you to Luke Blakemore for all of his
support and motivation throughout the
survey.
REFERENCES
Altmann, J. 1974. Observational study of behavior: sampling methods. Behaviour, Vol 49, pg 227-267. Bonner, W.N. 1972. The Grey Seal and Common Seal in European Waters. Vol 10. pg461–507. Bonner, W.N. 1989. The Natural History of Seals. Christopher Helm Publishers Ltd. ISBN: 0-7470-0203-7. pg 196.
Lauren Clegg
Bowen, W.D. et al. 2002. Sustained exponential population growth of grey seals at Sable Island, Nova Scotia. ICES/CIEM International Publishing. Available through: http://icesjms.oxfordjournals.org/content/60/6/1265.full [04.12.10]
Bramwell Slater, P.J. 1999. Essentials of
Animal Behaviour. Cambridge University
Press, 1999. ISBN: 978-0521629966. Available
through:
http://books.google.co.uk/books?id=sEOePcIF
W0IC&lpg=PA1&ots=sfVnXz8okN&dq=animal
%20behaviour%20ethogram&lr&pg=PA1#v=o
nepage&q=animal%20behaviour%20ethogra
m&f=false [01.12.10]
CSG (Cornwall Seal Group) 2009. Grey Seals in Cornwall. [online] Available at: http://www.suesseals.eclipse.co.uk/Seal%20Flier%20landscape%20V10%202009.pdf [07.12.10] Evans, P.G.H & Hammond, P.S. 2004.
Monitoring Cetaceans in European Waters.
Mammal Rev, 2004. Vol 34, (1) pg 131-156
Fedak, M.A. et al. 1996. MAMVIS: A Marine Mammal Behaviour Visualization System. Volume 7, Issue 3. pg 141-147
Guillemin, J. 1980. Anthropological Realities:
Readings in the science of culture. Transaction
Publishers, 1980. ISBN: 978-0878557837.
Available through:
http://books.google.co.uk/books?id=ddQwYc
_2RGoC&lpg=PA444&ots=LD_F_9sEjg&lr&pg=
PA446#v=onepage&q&f=false [04.12.10]
Haug, T, M Hammill, D Olafsdottir 2007. The grey seals in the North Atlantic and the Baltic., The North Atlantic Marine Mammal Commission, Tromsø. NAMMCO Scientific Publications Vol. 6. Available through: http://www.marinemammalscience.org/index.php?option=com_content&view=article&id=476&Itemid=309 [05.12.10]
Higham, J.E.S. & Luck, M. 2008. Marine
Wildlife & Tourism Management: Insights
from the Natural and Social Sciences. CABI
Publishing, 2007. Available through:
http://books.google.co.uk/books?id=TsRZW0
dU-
6MC&lpg=PA182&ots=O1JFouXMaG&dq=grey
%20seal%20code%20of%20conduct&lr&pg=P
A182#v=onepage&q&f=false [01.12.10]
IUCN, 2010. Red List of Threatened Species.
[online] Available at:
http://www.iucnredlist.org/apps/redlist/detai
ls/9660/0 [05.12.10]
IUCN: The World Conservation Union, 1995.
Seals. Cambridge: IUCN Publications. ISBN 2-
8317-0049-3
Kiely, O. et al. (2000). Grey Seals: Status and Monitoring in the Irish and Celtic Seas. Maritime Ireland / Wales. Report No. 3. ISSN: 1393-9025. Pg 77 Leeney, R.H. et al. 2010. Abundance,
distribution and haul-out behaviour of grey
seals (Halichoerus grypus) in Cornwall and the
Isles of Scilly, UK. Vol 90(5). Pg 1033-1040
Lewis, K.M. 2006. Habitat Use, Haul-Out Behaviour & Site Fidelity of Grey Seals (Halichoerus grypus) along the Ceredigion Marine Heritage Coast, Wales. Pg 1-30 Lockley, R. M. 1966. A ‘Survival’ Book: Grey Seal, Common Seal: An account of the life histories of British seals. White Lion Publishers Ltd. pg 175. McConnell, B.J. et al. 1999. Movements and foraging areas of grey seals in the North Sea. Vol 36. Issue 4. Pg 573-590. Available through: http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2664.1999.00429.x/full [05.12.10] Moore, P.G. (2003). Seals and fisheries in the
Clyde Sea area: traditional knowledge informs
science. Fisheries Research, Vol 63. Pg 51-61
Natural England. 2009. Formal consultation starts on proposed European marine sites: EC Habitats Directive 1992. [online] Available at:
Lauren Clegg
http://www.naturalengland.org.uk/about_us/news/2009/271109.aspx [04.12.10] Port of Truro Authorities, 2001. The Fal Estuary. [online] Available at: http://www.portoftruro.co.uk/pdf/leaflets/falest.pdf 2001 [05.12.10] Prime, J.H. 1985. The Current Status of the Grey Seal Halichoerus grypus in Cornwall, England. Vol 33. pg 81-87
Riedman, M. 1990. The Pinnipeds: Seals, Sea Lions and Walruses. University of California Press, 1990. ISBN: 978-0520064973. Available through: http://books.google.co.uk/books?id=McNEUgU8Q58C&lpg=PR9&ots=hn4tDRuYhR&dq=pinnipeds&lr&pg=PP2#v=onepage&q&f=false [04.12.10] SCOS, 2007. Scientific Advice on Matters Related to the Management of Seal Populations. pg 1-93. Available through: http://www.smru.st-andrews.ac.uk/documents/SCOS_2007_FINAL_ADVICE_1.pdf [04.12.10] Smithsonian Institution, 2010. Vocabulary list. [online] Available at: http://nationalzoo.si.edu/Education/ClassroomScience/vocabularylist.cfm [06.12.10] SMRU: Sea Mammal Research Unit. 2010. Seal Diet. [online] Available at: http://www.smru.st-andrews.ac.uk/documents/SealDiet.pdf [05.12.10]
Steven G.A. 1932. A short investigation into the habits, abundance and species of seals on the North Cornwall Coast. Report to the Ministry of Agriculture and Fisheries, 30 December 1932. Available through: http://sabella.mba.ac.uk/823/01/A_short_investigation_into_the_habits,_abundance,_and_species_of_seals_on_the_North_Cornwall_coast.pdf [05.12.10] Summers, C.F. 1974. The Grey Seal (Halichoerus grypus) in Cornwall and the Isles of Scilly. Vol 6, No 4. pg 285-291 Thompson, P. & Rothery, D.P. 1986. Age and sex differences in the timing of moult in the common seal, Phoca vitdina.[05.12.10] Walker, D. and Wilson, A. 2007. Whales and
Dolphins of Great Britain: Where to go and
What to see. Loughborough: Cetacea
Publishing.
Wynn, R.B. et al. 2009 SeaWatch SW Annual Report 2009. pg 2-5
Lauren Clegg
APPENDICES
STATISTICS
Paired t-test
©Brilliant stats, Curriculum Press 2003
H0: there will be no difference in the behaviour between two haul out sites- CANNOT BE REJECTED
H1: there will be a difference in the behaviour between two haul out sites - REJECT
ETHOGRAM USED DURING SURVEY
BT Bottling Sleeping upright in the sea. Head will rise and sink at the surface.
LG Logging Sleeping in the sea horizontally.
SP Splashing Sudden diving action if disturbed.
IO Interaction with other seals Grooming, playing etc. with other seals.
FD Feeding Can be seen eating fish, crabs etc. usually at the surface of the water.
HL Hauling from sea to land A seal will haul from the water onto haul out zone.
EW Entering water from land A seal will enter the sea from the haul out zone.
LY Lying Sleeping motionless on land on their backs or sides.
GR Grooming Scratching themselves with their paws.
FN Fanning Stretching back flippers into a fan.
TK Tracking Surfacing behind a boat following it.
SK Snorkelling Blowing bubbles whilst swimming at the surface.
BN Banana-ing Seal tail and head held high, in a U or banana shape.
Behaviours Black Rock Gwennap Head
BT 0 2 -2
IO 2 0 2
HL 1 3 -2 s = ∑x2 - mean2
LY 8 3 5 √ n
GR 0 1 -1
SK 0 3 -3 ∑x2 145
BN 2 0 2 mean = -0.9
DV 0 6 -6
PR 0 7 -7 s = 145 - 0.81
SC 5 2 3 √ 10
s = 3.7
ttest = - 0.9 √ (10-1) = 0.729
3.7
Degrees of freedom = 10 - 1 = 9
Critical value = 1.833
t value is lower than the critical value so
null hypothesis can not be rejected
Lauren Clegg
DV Diving Diving underwater suddenly.
PR Periscoping Head held high whilst in water, looking around.
SC Scanning Looking around whilst hauled out on land
MAPS/GRAPHS
0
2
4
6
8
10
Black Rock Gwennap Head
Haul Out Sites
Total Number of Halichoerus grypus Observed
Number of Halichoerusgrypus observed
0
1
2
3
4
5
6
7
8
9
BT LG SP IO FD HL EW LY GR FN TK SK BN DV PR SC
Nu
mb
er
of
tim
es
acti
on
s ta
e p
lace
Behaviour
Behaviours of Halichoerus grypus observed at two haul out zones
Black Rock
Gwennap Head
Lauren Clegg
GWENNAP HEAD
4%
46%
14%
16%
3%
9%
3% 5%
Behaviours observed at Gwennap Head
SC LY SK BT DV PR HL GR
Gwennap Head haul out site
View point, Cliff tops of Gwennap
Head
Lauren Clegg
BLACK ROCK, FAL ESTUARY
0
0.5
1
1.5
2
2.5
3
3.5
09
/03
/20
11
11
/03
/20
11
13
/03
/20
11
15
/03
/20
11
17
/03
/20
11
19
/03
/20
11
21
/03
/20
11
23
/03
/20
11
25
/03
/20
11
27
/03
/20
11
29
/03
/20
11
31
/03
/20
11
02
/04
/20
11
04
/04
/20
11
06
/04
/20
11
08
/04
/20
11
10
/04
/20
11
12
/04
/20
11
14
/04
/20
11
16
/04
/20
11
18
/04
/20
11
20
/04
/20
11
22
/04
/20
11
24
/04
/20
11
26
/04
/20
11
Gwennap Head: Tidal height variation vs. Seal observations
tidal height /m
Number of Grey seals
View point, Pendennis Point,
Falmouth
Black Rock, Haul out site
Lauren Clegg
78%
4%
16%
0% 2%
Behaviours observed at Black Rock
LY SC IO HL BN
0
0.5
1
1.5
2
2.5
11
/03
/20
11
13
/03
/20
11
15
/03
/20
11
17
/03
/20
11
19
/03
/20
11
21
/03
/20
11
23
/03
/20
11
25
/03
/20
11
27
/03
/20
11
29
/03
/20
11
31
/03
/20
11
02
/04
/20
11
04
/04
/20
11
06
/04
/20
11
08
/04
/20
11
10
/04
/20
11
12
/04
/20
11
14
/04
/20
11
16
/04
/20
11
18
/04
/20
11
Black Rock: Tidal height variation vs. seal observations
Tidal height
Number of seals
Lauren Clegg
MARINE MAMMAL CODE OF CONDUCT
Marine mammal watching has become a huge tourism industry; in turn needing to create a code of
conduct, for the correct manner of behaviour whilst watching these creatures and with the tourism
increasing as does the knowledge and conservation of these wonderful marine mammals. (Garrod &
Fennel, 2004) All wild marine mammals are vulnerable to disturbance of any kind if not approached
correctly. There must be complete understanding of the code for it to work. (WiSe, 2010)
Code of Conduct as put forward by the Cornwall Wildlife Trust:
Keep your distance
Never drive a boat head on into a group of animals as to separate them
Please spend no longer than 15 minutes near these animals
Avoid groups with mother and young
Never be a cause of marine litter or marine contaminants – take your rubbish home
Never swim with a marine mammal, for both your safety and theirs
Maintain a steady direction, preventing any wake
Never attempt to feed a wild marine mammal