Palacios, Daniel M.

Aquatic Commons

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.
luly 7995 NOTICIAS DE GALAPAGOS
Table 1. List of cetaceans recorded from remains in Galápagos.
Asterix indicates specimens in the reference collection of the
museum of the Charles Darwin Research Station (CDRS).
delphis skulls I examined (for example, specimens V-591
and V-1182). The cranial measurements also show that
the skulls are smaller than the skulls of D . delphis tnGalâp a-
gos'
These diagnostic characteristics (Evans 1994; Perrin
and Hohn 1994) allowed me to re-identify specimens V-
857, V-858 and V-859 as pantropical spotted dolphins
(Stenella attenunta), not the more abundant short-beaked
common dolphins as originally labeled (Fig. 1). William
F. Perrin subsequently confirmed the re-identification of
these skulls.
ACKNOWLEDGMENTS
This study was possible thanks to the collaboration
and patience of many people who kindly allowed me to
inspect the specimens under their care or guided me to
sources of information. I would like to single out Linda
l. Cayot, David Day, Gus Angermeyer, Heidi M. Snell,
Tjitte de Vries, Gayle Davis-Merlen, Liz Pillaert and espe-
COMMON NAME
Rough-toothed dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Striped dolphin
Short-beaked common dolphin
False killer whale
Short-finned pilot whale
Ginkgo-toothed beaked whale
Cuvier's beaked whale
Sperm whale
Dwarf sperm whale
Rorqual sp.
SCIENTIFIC NAME
Steno bredønensis
Grampus griseus
Tursiops truncatus *
Stenella attenuata *
Stenella coeruleonlbn
Delphinus delphis *
Pseudorca crøssidens
Globicephaln
macrorhynchus *
Mesoplodon ginkgodens *
Ziphius caairostris "
P hy s et er m a cr o c eph alu s
Kogia simus
Balaenoptern sp.
Figure 1. Dorsal and ventral views of skulls of Stenella attenuata (Cat. No. V-858) on the left and Delphinus delphis (Cat. No. V-591)
on the right, from the reference collection of the Charles Darwin Research Station. In the ventral view, note the flat palate of S.
attenuata (bottom left) and the grooved palate of D. delphis (bottom right). Also note the medial fusion of the premaxillaries in the
dorsal view (top right), another character used in distinguishing Delphinus (Tomilin, 1967).
NOTICIAS DE GALAPAGOS No.55
cially the late Mao Ortuño, who inspired and encouraged
me to undertake this study. William F. Perrin confirmed
the re-identification of the S. øttenuata skulls. I also thank
the Galápagos National Park Service, the Charles Darwin
Research Station and the Ecuadorian Navy for providing
necessary permits and logistical support. TAME kindly
provided reduced airfare to the islands.
LITERATURE CITED
Day,D.7994. List of cetaceans seen in Galápagos. Noti-
cias de Galápagos 53:5-6.
Evans, W.8.1994. Common dolphin, white-bellied por-
p orse D elphinus d elphis Linnaeus, 77 58. In : S.H. and R.
Harrison, eds. Handbook of marine mammals, Vol. 5.
The first book of dolphins. Academic Ptess, London.
Pp.191-224
Orr, R.T. 1965. The rough-toothed dolphin in the Galápa-
gos Archipelago. Journal of Mammalogy 46(1):101.
Palacios, D.M.7995ø. Cetaceanremains and strandíngs in
the Galápagos Islands. Proceedings of the Northeast-
ern Regional Stranding Network Conference, 28-30
April1995. Riverhead, NY, USA (abstract).
Palacios, D.M.1995b. A specimen of Mesoplodon gink-
godens fromthe Galápagos Islands. Proceedings of the
XX International Meeting for the Study of Marine
Mammals, 18-21 April 1995. LaPaz, BCS, Mexico (ab-
stract).
Perrin, W.F., and Hohn, A.A.1994. Pantropical spotted
dolphin Stenella attenuata. In: S.H. and R. Flarrison,
eds. Handbook of marine mamtnals, Vol. 5. The first
book of dolphins. Academic Press, London. Pp. 99-
128
Tomilin, A.G.1967. Mammals of the U.S.S.R. and adja-
cent countries. Cetacea Vol. IX. Translated from
Russian by the Israel Program for Scientific Transla-
tions. Smithsonian Institution and National Science
Foundation. USA.
Daniel M. Palacios. Whale Conservation Institute, L91
Weston Road, Lincoln, MA 01773, USA.
POLLEN DIGESTION IN GALÁPECOS LAVA LIZARDS
By: K. Thalia East
(née K. Thalia Grant)
INTRODUCTION
Pollen grains contain a rich interior of nutuients, in-
cluding all the essential amino acids and vitamins for
growth and development (Faegri and van der PijI1971.,
Stanley and Linskens 7974). Howevet, the outer coat (ex-
ine) is highly resistant to penetrationby digestive enzymes
(Heslop-Harrison 1971) andthe degree to which animals
are able to use pollen as a nitrogen source is highly vari-
able. Digestion occurs when digestive enzymes degrade
the exine or penetrate the interior via the germination
pore (Gilbert1972, Stanley and Linskens1974, Simpson
and Neff 1983). The proportion of empty to full grains in
the faeces of animals is thus generally considered anindi-
cator of the extent of digestion (Brice et a1..7989).
Pollen digestion has primarily been investigated in
bees and other arthropods (e.g. Gilbert 1972, Srnith and
Mommsen 1984, Peng et al. 1986), but has also been found
in some bats (Howell1974,Law 1992), birds (Churchill
and Christiansen 1970,Paton 1981, Wooler et al. 1988,
Brice et aL.1989) and marsupials (Turner 1984, Richard-
son et al. 1986, Goldin gay 7990) (see Table L ). The western
pygmy possum (Cercørtetus nanus) and the honey pos-
suln(Tørsipesrostratus) are able to digestup to 100% of the
pollen they consume (Turner 1984, Richardson et aI.1986),
whereas the Queensland blossombat (Sy cony cteris austr a-
Iis) and another nectar-feeding marsupial, the
yellow-bellied glider (Pe taur us nustr ølls ) digest only about
50% (Goldingay 7990,Law 1992). \¡\trhile ability to digest
pollen has been investigated in several bird species, only
purple-cro*.ned lorikeets (Glossopsittø porphyrocephalø),
New Holland honeyeaters (Phylidonyris noaaehollandiae),
zebra finches (Poephilø guttata) and budgerigarc (Melop-
sittacus unduløtus) have been found to digest pollen and
with less than 50% efficiency (Paton 1981, Wooler et al.
1988). In contrast, the sharp billed cactus finch (Geospizø
scøndens) was recently found to digest pollen of Opuntiø
echios onDaphne Island, Galápagos with over 90% efh-
ciency (8.R. Grant 1994,pers. comm.).
The efficiency of pollen digestion has not been inves-
tigated in lizards. The benefit of including pollen in the
diet would primarily be its rich nitrogen content as well
as being a source of lipids and carbohydrates. Nonethe-
less consumption of pollen amongnectar-eating geckos is
generally dismissed as accidental and having little or no
nutritional importance (Elvers 7978,Thorpe and Craw-
ford7979 ,r{hitaker 1987 ,7987 ø) . Ontl':re other hand, Evans
and Evans (L 980) and Gardener (1984) suggest that pollen
may be an important component of the diet of Phelsuma
geckos in the Seychelle Islands since at least four species


Reidentification of three dolphin skulls in the museum of the

Charles Darwin Research Station

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Reidentification of three dolphin skulls in the museum of the Charles Darwin Research Station

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