fin whales (Balaenoptera physalus)

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located by one or more lookouts who were situated at high points along the coast ... the last three years, as photographic effort was very low in previous years.
Temporal
distribu0on
of
the
most
sighted
baleen
 AD31
 whales
in
Azores:
fin
whales
(Balaenoptera
 physalus)
and
sei
whales
(Balaenoptera
borealis).
 
Sardà,Clara1;
González,Laura1,2
&
van
der
Linde,Miranda1



(1)Futurismo
Azores
Whale
Watching,
Marina
Pêro
de
Teive,
9500‐771,
Ponta
Delgada,
São
Miguel,
Azores;
(2)Department
of
 Applied
Physics,
Vigo
University.


Corresponding
author:
[email protected]

Every
 year
 several
 species
 of
 baleen
 whales
 pass
 the
 Azores
 archipelago
along
their
migraFons2,3
 .SighFngs
are
more
frequent
in
 spring
Fme,
with
sei
whales
(Balaenoptera
borealis)
and
fin
whales
 (Balaenoptera
 physalus)
 having
 the
 highest
 sighFng
 rates
 of
 the
 baleen
whales.

 This
aims
of
this
study
were
to
analyse
the
temporal
distribuFon
of
 fin
 whales
 and
 sei
 whales
 and
 
 to
 photographically
 idenFfy
 fin
 whales
sighted
off
São
Miguel
island,
Azores.



• Around
 68%
 of
 fin
 whale
 encounters
 and
 55%
 of
 sei
 whale
 encounters
were
in
April
and
May
(Fig.
4,
Fig.
5),
although
we
have
 seen
them
throughout
the
rest
of
the
year
as
well,
but
with
much
 lower
rates.


Fig.
4.
Temporal
distribuFon
of
fin
whale
(Balaenoptera
physalus)
sighFngs
from
2006
to
2012.


Fig.
1.
Two
photos
on
the
le]
of
fin
whales
and
the
two
photos
on
the
rigth
of
sei
whales.


Data
 we
 analysed
 were
 collected
 between
 2006
 and
 2012
 off
 the
 south
coast
of
São
Miguel
during
commercial
whale
watching
tours
 with
 Futurismo
 Azores
 Whale
 Watching
 (Fig.
 2a).
 Cetaceans
 were
 located
 by
 one
 or
 more
 lookouts
 who
 were
 situated
 at
 high
 points
 along
 the
 coast,
 searching
 with
 powerful
 binoculars.
 Data
 were
 registered
in
situ
by
one
or
more
biologists
and
guides
aboard.

 Fin
 whales
 were
 photographically
 idenFfied
 (Fig.
 2b)
 based
 on
 the
 shape
 of
 their
 dorsal
 fin
 and
 other
 disFnguishing
 marks.
 All
 ID‐ photos
were
compiled
into
a
photographic
catalogue
of
individuals.


Fig.
5.
Temporal
distribuFon
of
sei
whale
(Balaenoptera
borealis)
sighFngs
from
2006
to
2012.


• 45
different
fin
whales
were
idenFfied,
mostly
from
encounters
in
 the
 last
 three
 years,
 as
 photographic
 effort
 was
 very
 low
 in
 previous
years.


 Fin
 and
 Sei
 whales
 are
 the
 most
 sighted


baleen
whale
species
in
this
study.


 The
 archipelago
 of
 the
 Azores
 is
 a
 poten0al


Fig.
2
a)
Futurismo
boat
watching
a
fin
whale.


b)
One
of
the
fin
whales
idenFfied
(Bp7).


• 
 Fin
whales
were
the
most
sighted
baleen
whales
in
this
study
 (Fig.
 3),
making
up
34,84%
all
baleen
whale
sigthings.
Sei
whales
were
the
 second
most
sighted,
making
up
34,57%
of
the
sighFngs
(Fig.
3).

 %
sigthings
of
baleen
whales
 1,32


Balaenoptera
edeni


3,98


Balaenoptera
acutorostrata


4,78


Megaptera
novaengliae


20,47


Balaenoptera
musculus
 Balaenoptera
borealis


34,57


Balaenoptera
physalus


34,84
 0


5


10


15


20


25


30


35


Fig.
3.
Percentage
of
sighFngs
of
baleen
whales
on
the
south
coast
of
São
Miguel,
Azores.


area
of
passage
of
migratory
routes
of
baleen
 whales,
especially
during
the
springFme.
The
 next
 step
 will
 be
 to
 determine
 how
 envi ro n menta l
 fa cto rs
 i nfl u en ce
 t h e
 occurrence
of
these
whales
in
the
Azores.

  45
fin
whales
have
been
iden0fied.
Although
 we
did
not
re‐sight
any
fin
whales
during
the
 study
 period
 photographic
 effort
 should
 be
 ongoing
 as
 
 can
 be
 an
 important
 source
 of
 informaFon
 on
 a
 larger
 Fme
 scale.
 In
 the
 future
 it
 may
 be
 possible
 to
 compare
 our
 photographic
catalogue
of
fin
whales
to
those
 from
 other
 nearby
 regions,
 in
 order
 to
 learn
 more
about
fin
whale
migraFon.


Acknowledgments
 We
want
to
acknowledge
the
company
“Futurismo
Azores
Whale
Watching”
and
the
team
involved
in
data
collecFon
for
this
project.
We
warmly
thank
all
the
 tourists
who
sent
us
pictures.


Bibliography
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whales
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relaFon
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