Merlen, Godfrey

English

Aquatic Commons

NOTICIAS DE GALAPAGOS No.55
staff, communicate with field camps and send data over-
seas. Staff members at the station were able to consult
with colleagues around the world. The importance of and
dependence onE-mail atthe stationbecame obviouswhen
the modem failed and the station was without E-mail
contact f or over a month. It was quite a relief when a sPare
modem was brought to the station to prevent E-mail from
vanishing again. As with so many things, you don't ap-
preciate something until it is gone.
The E-mail system at the station continues to evolve.
A UNIX server, designed to handle mail more reliably,
has just been installed. A more extensive network is cur-
rentlybeinginstalled, providing Internet access to several
more computers at the station. Soon the staff will be
introduced to the "World Wide Web" (WVVW), an infor-
mation network offering access to libraries, scientific data
sets, and news on the latest developments in science from
around the world. Not only can this service be used from
CDRS to obtain information from around the world but
CDRSplans to eventuallybecome aWVWV site itself, con-
tributing information about the station, petsonnel,
research projects, and even select data sets. The next time
you venture on the "Information Super Highway", keep
your eyes open for a giant tortoise, moving slowly but
surely forward.
fim Pinson, Charles Darwin Research Station, Isla San-
ta Ctuz, Galápagos, Ecuador.
FUNDAMENTALS
By: Godfrey Merlen
The eruption on Fernandina Island that occurred to-
ward the end of January 1,995 was a spectacular event. For
the first time in many years, a large number of people
were able to witness a geological "hot spot" in action. The
copious quantities of lava that reached the ocean to the
west and the interconnecting rivers of fast-flowing mol-
ten rock left all who saw it with a powerful image of light
and energy. At night, the lurid red clouds painted against
the dark sky gave the impression of a penetrating ball of
light. Perhaps even Benjamin Morrell would have been
impressedby this awesome sight. Unfortunately, pitchis
not a chandler's item these days and itwas notpossible to
repeat his observations of 1825!
I visited the area on three seParate occasions (January
27-30,February 6-7 andMarch 18-19). Iwas authorizedto
land with André Mauchamp on the second trip and with
Mitsuaki Iwago and Kiyoshi Yokokawa from NHK (Jap-
anese National Television) on the third trip. I plotted
positions of the forming fissures, cones, and lava flows
using aportable GPS (Global Positioning System)instru-
ment because observational satellites are out of
commission and no aerial photographs of this event will
be forthcoming.
Onthenight of February 6,whilenear the source of the
eruption, I noticed that a strong flow had developed south
of the general pattern of lava channels to the west. This
new flowheadedwithunerring accuracytowardtheland-
ing at Cape Hammond. On the morning of the 7th, I crossed
a smoky lava field to Iguana Hill, part of an old cone
surrounded by new lava, and climbed to its top. The hill
is about 1 km from the "source". At the foot of the hill, the
flow diverged andhuge quantities of moltenrockrushed
westward in fast-flowing rivers. These rivers occasional-
lybecame dammed with enormous, semi-solid boulders
the size of houses. On breaking free, the magma surged
down steep lava falls with the fluidity of water. Vegeta-
tion vanished in spurts of flame and puffs of smoke.
The huge red flows were a striking contrast to the sil-
ver-grey palo santo trees on top of the hill, many of which
hadbeen felled every-which-wayby the initial release of
pressure from the eruption. Behind me, the center of the
growing source cone displayed a continuous fountain of
moltenmaterial,falling as scoriahundreds of meters away.
By day, the fountainwasblood red;bynight, a golden arc.
Upon descent, I found that the lava flow had cut off
my easy retreat across a large pahoehoe field. Its length
was about 4 km, leaving over L kmbetween its front and
the landing at Cabo Hammond. This front has not ad-
vanced, but that day I could see the white-hot interior
through cracks between boulders, indicating some move-
ment was still occurring. Several smaller flows have since
moved in the same direction between February 6 and
March 6, but no more than about 1.5 km from the cone'
Cape Hammond offers a refuge from the swells that
continuouslybatter the coastline from the south. It is the
only protected landingbetween Cape Dougias in the north
and Punta Mangle to the east, since wave action has pro-
duced vertical cliff faces on the west and south sides of the
island. The small bay at the landing is thus a unique
feature of this coast and is the result of previous lava flows
to the south; an accident of time and place. The bay, with
its two boulder beaches and a sandy beach behind a shal-
low protected pool, is a haven for endemic fur seals,
flightless cormotants, marine iguanas, and penguins. Even
lwly 1995 NOTICIAS DE GALAPAGOS
I
Photographs of the Fernandina eruption taken in March 1995by Susan Noftsker.
though the eruption is a totally natural event, there is
human concern f or this unique, remote spot behind which
the gaping earth is transforming the face of the land irre-
vocably and irreparably. The same forces that created the
Galápagos are now facing the life forms molded by natu-
ralselectiononthese islands. Nonetheless,inthese animals
I saw no fear of what might be, no collapse into panic or
immobility in the face of imminent disaster 
- 
reactions
which might well have been our own. The fur seal pups
leaped and played in their secure pool. The cormorants
dried their wings on the small pointbetween theboulder
beaches. They were even attempting to breed 
- 
one pair
now has two eggs in a well-made alga nest. \Mhile a smoke
pall drifted over the bay, marine iguanas were digging
nests in the dark sand beach behind the fur seal pool.
Even when the sea temperature in the bay rose to 32"C
and the surface turned green, the animals proceeded as if
nothing had happened. Life is naiVe; perhaps that is why
it has survived in spite of the physical dynamics of an
often volcanic planet.
On the other hand, thousands of fish died when copi-
ous amounts of lava plunged into the water, violently
changing the natural rhythm of the sea. Low-frequency,
echoing explosions could be heard through hydrophones,
miles offshore. The temperature near the coast rose to
boiling point. Violent upwellings of cold water, which
seemed to be the result of molten lava entering the sea,
were juxtaposed with this steaming cauldron. Stresses of
pressure, temperature, acoustics, and chemistry exceed-
ed the limits that fish could tolerate. The seabirds took
advantage of the mass piscine mortality. Eels, damself-
ish, scorpionfish, and serranids were eagerly devoured
by frigatebirds and pelicans. Some birds were scalded in
the process of diving for food. A number of marine igua-
nas, following their life course too close to the lava flows,
were doomed. Thecoastal algabedswere destroyed. Some
iguanas, in the path of the molten lava, reacted to the
increasing heat by raising their bodies in their ancient
way of cooling themselves. As the heat increased, they
tried moving to higher ground,whichinsome cases meant
walking directly onto flowinglava, where the extreme
temperatures overwhelmed them.
High up on the flank of the volcano, where the lava
pumped forth onto the surface of the island, land iguanas
also perished in the confusion. One land iguana had
moved onto a new lava slope which was still blisteringly
hot when I arrived. The dead animal stood immersed in
the lava, with its head strained upward, its tail tightly
coiled, and arms stretched to full extent 
- 
its extremities
had vanished. Cactus plants surrounding the cone were
blistered on the side facing the heat; many other species
of shrubs appeared dead. The palo santos stood with
golden brown leaves, crisped by the earthly furnace.
On my second visit to this highland region (March 18-
19), Iwas able to approach, throughthe smoke, to thebase
of the cone. There I found land iguanas crunching over
the deep scoriabed and saw, under theblack slopes of this
new slag heap, an iguana raise itself up while a mocking-
bird removed parasites from its red-gold legs. I saw the
land iguanas tucking in on the new, fresh leaves thatwere
pushing forth from the shrubs that I had previously
thought dead. Within a meter of the still hot lava, an
Opuntia cactus had put forth new pads and flowers.
Amidstthe tangle of brokenpalo santo trees tornfromthe
ground, the silver bark split from the brown-gold sap-
wood beneath, the new volcano in its awesome and
beautiful fury showered down scoria, which in a little
while will produce new soil. Life on this planet is naïve,
but has an opportunism built into it that is capable of
dealing with such bizarre situations.
If all that we see happening in this absolutely natural
event is acceptable, why should we be concerned for the
life at the Cape Hammond landing? In part, it is because
of what we have learned of the fragility and vulnerability
of Galápagos life. The physical forces that affect the solid
part of the planet are unpredictable. Their expression is
primitive and awesome and their effects are uncontrolla-
ble. The life on these oceanic islands is naïve and helpless
when faced with extremes. Perhaps the tortoise popula-
tion on Fernandina was annihilated by eruptions such as
NOTICIAS DE GALAPAGOS No.55
this one. The same week that I ventured on land at Cape
F{ammond, I also went ashore at Punta Mangle, a man-
grove haven on the southeast corner of Fernandina. Tied
to the island was a dinghy with eleven loose goats on it.
I rubbed the head of one and she seemed to appreciate
it in her innocence. If given a chance, these goats, inno-
cent of impending doom, would at a moment's notice
step onto the molten lava flows in order to reach the
vegetation.
After the volcano has silenced itself, perhaps black
rats will arrive. Perhaps cats. In these days of change,
lEditor's Comment: In Noticiøs 54 the ørticle "Visitors
from the West" by Godfrey Merlen incorrectly remnrked on
the absence ofrecords of the red-shouldered (øIsoknown as the
r ed-spot or blue-Iined) wr asse (Stethojulis bandanen sis) from
the eastern P acific. This u)rasse, howeaer , høs been preuiously
recorded from Cocos Islqnd in the eastern Pøcific (Lopez, M.I.
ønd Bussing, W. A. 19 82. Rea. B iol. Tr op. 30 : 5 -26 ; B ussing,
W.A. L985. Reo. Biol. Trop. 33: 81-98). In øddition, recent
inoestigøtions at Clipperton Atoll reoeøl øn øbundant populø-
tion of this species. S. bandanensi s is also listed in " F ishes of
the sapphire-eyed cormorant and the myopic penguin are
in their last haven, for all other areas where they live are
irreversibly altered. Any loss of their populations seems to
jar at our well-being. ln their naïveté, they will vanish
forever, without regret. Only we fear the future, unable to
controlthe volcanoes of our ownminds, whichthreatenus
and confound our capability to defend a dying world.
Godfrey Merlery Charles Darwin Research Station" Isla
Santa Cruz, Galápagos, Ecuador.
the Tropicøl Eøstern Pncific" by Gerald R. AIIen ønd D. Ross
Robertson (Crawford House Press, Bøthurst, AustrøIia 1994) as
" widespreød in the tropical P acific Oceønfrom Austrølia to south-
ern | øpan, and eastward to islønds of the eøstern P acific, including
lsla del Coco, Clþperton Islønd and the Gølápagos, usuølly øs-
sociatedwith corølreefs" . Thusfar their occurrence in the tropical
eastern Pacific is limited to ffihore islands. We thønk Godfrey
Merlen, l erry W ellington and G ayle D aais-Merlen for pr ouid-
ing this correction.f
RE-IDENTIFICATION OF THREE DOLPHIN SKULLS IN THE MUSEUM OF THE
CHARLES DARWIN RESEARCH STATION
By: Daniel M. Palacios
While working for the Whale Conservation Institute
in Galápagos between February 1993 and March7994,I
undertook a study documenting the remains of cetaceans
thathavebeenfoundwashed ashore ontheislands. Some
preliminary results are presented here, including the re-
identification of three specimens from the reference
collection of the Charles Darwin Research Station.
Of the 22+ cetacean species that have been observed
in Galápagos waters (Day 1994), L3 are represented by
beached specimens collected since William Beebe's ex-
pedition in 1923 (P alacios I995a) (Table 1) . The remains
of a rough-toothed dolphin (Stenobredønensis) (Orr 7965),
and a ginkgo-toothed beaked whale (Mesoplodon gink-
godens) found on Genovesa tn 1970 by Tjitte de Vries
(Palacios 1995b) provide the only evidence that these two
species occur in Galápagos. S. bredanensis prelerswarm-
er waters than those normally found around Galápagos
and M. ginkgodens has never been seen alive anywhere.
At least 29 specimens are housed in 8 scientific collec-
tions and 19 more are housed in private collections (Pala-
cios1995a). The museum of the Charles Darwin Research
Station alone contains a reference collection of al]east22
specimens representing six species (Table 1).
I examined several of the specimens at the Charles
Darwin Research Station and found that three skulls (cat-
alogue numbers V-857, V-858 and V-859) collected by ].
Webb on 1 April 7975 horr. the northwest coast of San
Cristóbal and labeled as short-beaked common dolphins
(Delphinus delphis) did notmatchthose typical for that spe-
cies. Close examination of the ventral side of the rostrum
revealed the absence of the two deep lateral grooves run-
ning longitudinally on the left and right palatine processes
of the maxillaries (also known as the palatal carination)
which distinguish the genus Delphinus from all other gen-
era of delphinids (TomiItnt967; Evans 7994). In addition,
I counted only 35-41 teeth (or alveoli when teeth were
absent) in the upper and lower jaws of these specimens, as
opposed to 45-50 teeth (or alveoli) in the jaws of other D.


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