Whitehead, Hal

English

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STUDYING SPERM WHALES ON THE GALAPAGOS GROUNDS 
by 
Hili Whitehead 
New/oundlond Institute for Cold Ocean Science, St John's, Newfoundland, Canada AlB 3)(7 
The presence of sperm whales(Physeter macrocepholus)around the Galapagos Islands was one oCthe most 
imponant factors in the: exploitation and degradation of the islands. During the nineteenth century large 
numbers of whalers from the U.S., Britain. France and other countries hunted the sperms of the 
Galapagos. During their visits on shore the whalers plundered tortoises and seals. There has been much 
research and writing about the destructive effects of the whaling industry but the whales themselves have 
been largely ignored in recent years. 
Between mid~February and late April 1985 we made a study of the spenn whales off the Galapagos from 
the 10 metre sloop, EJendil. With a crew of five (Tom Amborn, Amelia Brooks. Vassili Papastavrou, 
Linda Weilgart and Hal Whitehead) we located and followed groups of spenn whales using a directional 
hydrophone to listen (or their distinctive clicks. The principal objective of the study was to investigate the 
effectiveness of the waters around the Galapagos for studying the social behaviour ofspenn whales. We 
were particularly interested in the interactions between the apparently stable groupings of 2040 female 
spenn whales, with their young and the large mature males who spend much of the year in polar waters. 
migrating to the tropics for a few months to mate. We were hoping to gain infonnation on questions such 
as: for how long does a mature male associate with a group of mature females;and do mature males act in 
consort or competition with one another? These issues are particularly crucial to current attempts to 
model spenn whale populations (Anon. 1983). 
The research that we were undertaking was a consequence of the 1981·1984 World Wildlife Fund Indian 
Ocean Sperm Whale Study. which three ofus(V. Papastavrou, L. Weilgart.and H. Whitehead),aswellas 
our sloop E/endil. had taken part in. During the Indian Ocean Project we had developed methods of 
finding, tracking and studying spenn whales (summarized by Whitehead and Gordon, in press). When it 
ended we wondered if there might be a better research area where we could continue our investigations of 
spenn whale behaviour. Sri lanka, our major study area in the Indian Ocean, had many advantages, but it 
was very far from my home in Canada, extremely hot, swept by monsoons which made research almost 
impossible for half the year, and has recently become embroiled in political tunnoil. However, its most 
significant disadvantage was a lack of the large male spenn whales because during our months in the 
Indian Ocean we had seen only three large males, and these briefly. At that rate it would take many years 
to obtain any understanding of the crucial interactions between the large males and the groups offemales. 
We examined maps of where the 19th century Yankee whalers made their kills (e.g. Townsend 1935),aOO 
also charts of ocean weather conditions. The ocean area that the whalers called "The Galapagos 
Grounds" immediately stood out in tenns of the abundance of spenn whales, and the prevalent calm, 
relatively cool weather. The British had discovered the GaJapagos Groundsduring their late 18th century 
round·d'le·world explorations. Captain James Colnett aboard the ship Rattler made "A Voyage to the 
South Atlantic and around Cape Horn into the PaCific Ocean, for the purpose of extending the Spermaceti 
Whale Fisheries, and Other Objects of Commerce". He visited the Galapagos in 1793 and 1794, writing: 
"Everyone was chilrmed with the place" (Colnett 1798). They" saw spermaceti whilles in great numbers", 
and Captain Colnett recommended the Galapagos Grounds to British whalers. His advice was followed, 
particularly by the stubby American whaJeships sailing from New Bedford, Nantucket, and other New 
England ports. During the first part of the 19th century. the Galapagos fonned one of the Yankees' 
favourite grounds. At that time the whalers provided much ofthe western world'soil, and the whales were 
remorcelessly exploited. After 1850, presumably because the sperm whale populations had been depleted, 
the whalers found the Galapagos "dry cndsing" (Shuster 1983) and went there no more. 
The Galapagos seems to have mercifully escaped the attention of the ultra~fficient mechanized whalers of 
the 20th century, and there is little recent infonnation on the Galapagos Grounds. Some competent 
authorities warned us that we would be wasting our time off the islands, as there were a few whales and 
those far offshore. Others were more optimistic. The only way to find out was to sail there and see. 
We obtained the support of the Green Island FOUndation, the Connecticut Cetacean Society and a few 
private individuals. World WildJife Fund Netherlands allowed us to continue to use some of the 
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Noticias de Galapagos, vol. 42 1985
cqulpmenl from th~ Indian Oc~an Swdy.and so we saikd t1,."di/across Iht' AtlantiC Oc~an and through 
the I'anama Canal to reach the Galapagos in February 1985. Tht're. with excelle nt co-oper.ll ion from the 
Chanc:s ~rwi n Resea rch Station. INOCA R. and the Galapagos National Park Service:, we found 
condilions almost ideal for our resea rch. Th~ weather was vcrycalm and often pl<"asantlycool. Thefema le 
sperm whales w<:re in b rgc: groups that were: easy 10 track acow.tically. Most Importantly, the la rge maks 
"''ere of len in a tl~ndance. Captain Colnc:tt (1798) had advised: 
"The silUation I recommend to aU cmizers. is betwecn the South end o(Narborough Island (FernandinaJ 
and the Rock Redondo (Rc:donda).·· This region. where the: sub-surface Crom~ll CUrTenl . running eastwards • 
direc1ly beneath the Equato r, is foreN upwards by Ih~ islandsof lsabela and Ferna ndina. became the core 
ar~a (or our (ese.:lrch. The groups of sperms would sometimes stray a hundred kilo met res or so 10 the 
south or west, but it wa s between Fernandina and Redonda that they were most numerous. (See map on 
inside back cover). 
Sperm Whale breaching oil' the Galapagos. 22 Mareh 1985. 
Photo by: VassiJi Papastavrou 
During all the wc:c:ks that we have spent with sperm whales. the SUbjects of our ~arch have shown 
themselvcs to be: gentle a nimals. They are onen shy. but occasiona lly curious towards humans and their 
boau. Ho wevcr, with each other they display a vcry highlydevcloped sociality. Alth ough adjacent sperms 
are probably sepa rated by a few hundred metres when feeding at depth . off the: Galapagos they often 
appeared to be: co-ordinating by forming a rank scvcral kilometres long. with the whales swimming 
abreast of one another. These: ranks swept through the deep ocea n at a steady 2.5-3 knots (4.5-5.3 
kilometres per hour). for 24 hours or more. Individuals would come to the surfatt every (Orty minutes or 
so to breathe , but the whole phalanx bore on. 
" 
Noticias de Galapagos, vol. 42 1985
When foraging 400 metres beneath the surface, each individual made the characteristic regular (about 
once per second) click of the sperm whale, which is presumably a form of echolocation used for locating 
the large squid that they mainly eat. The jumble of clicks of a group of hunting sperms, which together 
sound rather like radio static, must foretell approaching death for many squid. BUlforus on board E1endil 
the clicks were an important key. We listened for them through a directional hydrophone. With this 
instrument we cou1d detect the bearing of a clicking sperm whale at about 8 kilometres and, by listening 
regularly and adjusting our course and speed depending on where and how loud we heard the clicks, were 
able to track groups of sperm whales for periods of days. 
Off the Galapagos, between 40 minute feeding bouts, the sperm whales remained at the surface breathing 
for about 8 minutes. During these periods the whales seemed irresistably drawn to one another; if there 
was another whale nearby, they would almost surely sidle up together for compani onship during their few 
minutes al the surface. The small calves, who did not dive deeply, were particularly active injoining adults. 
But once every day or two the whales ceased their feeding to congregate at the surface in sub-groups offive 
to forty animals for an hour or more. It was during these "social times" that the significance of their 
communal relationships was most apparent. Although from the deck of our boat the whales appeared like 
a raft of inanimate logs, when beneath the surface they were revealed as extraordinarily flexible, tactile and 
tender animals. Snorkelling behind Elendil, we saw them gracefu1ly turn to watch us with deep blinking 
eyes, gently stroke one another with their small flippers, or nuzzle a smooth bulbous brow against a vast 
wrinkled flank. 
We tracked the groups of sperm whales fortrurtydaysandnights. Much of what has been learnt about the 
social interactions of sperm whales will only befully apparentafteracomplete analysisofthe photographs 
(which we took to identify individuals by their natural markings), recordings of the whales' clicks and 
other data that we collected; but a few incidents revealed immediate insights. 
Very near the end of the study, the group that we were following had strayed over 180 kilometres west of 
Jsabela. It was morning and the whales, lined up in an east-west rank several kilometres long, wereclicking 
noisily and moving steadily to the south. But at 09.45 they suddenly became silent, and we spotted them 
clumped together in two large sub-groups a few thousand metres away. This was a dramatic change in 
behaviour, and quite unexpected as sperm whales usually shift gradually from the hunting/spread-
out/clicking phase of their behaviour to the social/congregated/silent phase. For an hourortwo Iessand 
less clicks are heard, and the sub-groups that the whales form at the surface become steadily larger. This 
sudden silence and the rapid formation of su))..groups was most unusual, but its reason was apparent when 
we saw the distinctive black and white shapes of orcas (O,cinus orca). 
The powerful 6-7 metre orcas, often called killer whales, probably the only serious non-human predator 
that sperm whales face, were circling the huddled sperms. For three hours we watched the attack. The 25 
or so sperm whales stayed extremely closely packed, and tried to keep themselves facing directly towards 
the nearest orcas. They were clicking rapidly and with great intensity. The head of the sperm whale with its 
powerful jaw and sophisticated acoustic system, is probably the least vulnerable part of the whale. The 
orcas, perhaps realizing this, in sub-groups or 2-5 would dart around the flank of the massed sperms to 
attack them from behind. The sperm whales would turn, trying to keep facing the orcas. There was one 
tiny sperm whale calf. It was kept right in the centre of the concentration, presumably the safest place. In 
contrast the only large male sperm whale in the group usually hung behind. Was he protecting their 
vulnerable rear, or just tagging along? The two large male orcas also hung back, taking little part in the 
action. Most of the c1ose.quarters interactions between the two species took place under water, hidden 
from us. We did see some fresh open wounds on several sperm whales, but none were particularly deep. It 
seems unlikely thatany ofthe sperms were badly injured. The whole attack seemed to constitute a skirmish 
in which the orcas tested the sperms to see if there were any particularly vulnerable animal, which might 
then be assaulted in force. 
The end of the incident was most interesting. The sperms began to turn in tight circles, the whole mass of 
whales revolving every 2-3 minutes. Perhaps the orcas now realized the futility of their attack for they 
began to move off to the west. With the orcas.500 metres away the sperm whales made their move, They 
fell totally silent and started travelling fast eastwards, remaining in their com pact sub-group. For six hours 
they maintained 5.5 knolS (9.5 kilometres per hour),and we motored after them. With the exception of the 
Noticias de Galapagos, vol. 42 1985
large male, who fell behind for a while and lost synchrony. the whales remained co-ordinate<! and tight-
packed throughout Ihe emire flight, which was unparalleled in our experience with sperm whales. They 
were also uncharacteristically silenl,again with the exception of the big male, who briefly broke the silence 
with his very slow distinctive click. When night came. the whales were continuing eastwards, but with no 
clicks our direclional hydrophone was useless, and they were lost to us. 
The incident was very instructive in showing how the top natural predator in the ocean attacks what is 
probably its mosl formidable prey. but it also conlained some important hinls about the relalionship 
belween Ihe large male sperm whale and the group to which it was attached. The male made considerable 
effort to stay with the group, although he did not seem to be a fully-integrated member of it, or, in any 
sense, to be leading it. He also broke the silence 'of the other sperms, thereby perhaps revealing their 
presence to the orcas. 
On returning from Ihe Galapagos il was particularly interesting to read the accounts and log-books of the 
whalers who had preceded us. So many of their comments, about the calms, currents, headlands, sperm 
whale behaviour or other marine life, could have come from our own journals. The most significant 
variations concerne<! observations about the density of sperm whales. After a very preliminary 
examination of the sources, our observations seemed to lie intermediate between those of Captain Coinett 
and his conlemporaries around the year 1800, who found "great plenty of whales", and the frustraled 
skippers of the second half of the 191h century scanning the horizon without any sign of the sperm whale. 
We look forward to analysing the data that we have collected for more indications of the social syslem of 
the spenn whale and, above all, to returning to the sperm whales on the Galapagos Grounds in a year or 
two. But in the meantime we must also worry lest any ofthe sperms thai we grew to knowstraynorthwest 
to the "Coast of Japan Grounds". There, the Japanese whalers, abetted by the US Government, are 
defying the International Whaling Commission's ban on sperm whaling. 
REFERENCES 
Anon. (1983) Report of the sub-commiUee on sperm whales. Rpl. Int. Whal. Commn. 33: 74-90. 
Clarke, R.(1962) Whale observation and whale marking off Ihe coast of Chile in 1958 and from Ecuador 
towards and beyond the Galapagos 1sIands in 1959. Norsk Hvalfangst-Tid. 51(7): 265-287. 
ColneU, J. (1798) A voyage to the South Atlantic and round Cape Horn into the Pacific Ocean. 1968 ed. N. 
Israel, Amsterdam. 
Shusler, G.W. (1983) The Galapagos Islands: a preliminary study of the effects of sperm whaling on a 
specific whaling ground. Rpt. IWC (Spec. Issue 5): 81-2. 
Townsend, C.H. (1935) The distribution of certain whales as shown by the logbook records of American 
whaleships. Zoologica 19(1I): 3-50. 
Whitehead, H., and Gordon, J. In press. New techniques of obtaining data for assessing and modelling 
populations of spe:nn whales which do not depend on catches. Rpt. Int. Whol. Commn. Spec. Issue. 
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Noticias de Galapagos, vol. 42 1985


Studying sperm whales on the Galapagos grounds

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Studying sperm whales on the Galapagos grounds

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