Varied underwater environments in different parts of the archipelago offer stunning encounters with Galapagos wildlife in both, warm and cold waters. An entertaining account of encounters with Galapagos wildlife on their rather cold side.

Whale Sharks, A-bombs and the Hubble Space Telescope
Whale Sharks, A-bombs and the Hubble Space Telescope
Pregnant whale shark female at Darwin Island in the Galapagos. In 2014, members of the Galapagos Whale Shark Project reported sightings of 27 whale sharks, all females, all but one pregnant around Darwin Island in the Galapagos archipelago.
Photograph © 2011 Josef Litt
We know very little about the biggest bony fish in the oceans, the whale shark.
Whale sharks are the world’s most giant fish, growing up to twenty metres in length – more than a bowling lane and almost as long as a passenger train coach. We don’t know how fast they grow and what is their maximum age. The best estimates are that the big ones may be more than one hundred years old.
The Atomic Bomb Method
Scientists determine the age of sharks by counting growth rings in their vertebrae. This method seems to provide reliable results for younger animals. However, one needs an atomic bomb to make the reading more precise in case of the older sharks. The nuclear tests performed in the 1950s and 1960s increased the amount of radiocarbon in the atmosphere. The radioactive material entered the oceans and imprinted a timestamp in the whale sharks vertebrae. Today, this timestamp helps to establish the age of older individuals.
Photograph © 2011 Josef Litt
The Hubble Space Telescope Method
To paraphrase Douglas Adams in the Hitchhiker’s Guide to the Galaxy: ‘Whale sharks are big. Really big. You just won’t believe how vastly hugely mind-bogglingly big they are.’
From that slightly facetious perspective, it is no surprise that the scientists use the Hubble Space Telescope to identify individual whale sharks. The spots behind their gills form an ornament as unique as a fingerprint. Jason Holmberg, the co-founder of WildMe.org, adapted an algorithm used by NASA with the telescope to recognise and compare the patterns. Thanks to that anybody who photographed a whale shark anywhere in the world can upload their images to the Wildbook for Whale Sharks. Almost 8,000 people identified more than 10,000 whale sharks during close to 60,000 sightings. The data give scientists information about the distribution and movement of the gentle giants, hopefully leading to their adequate protection.
‘Whale sharks are big. Really big. You just won’t believe how vastly hugely mind-bogglingly big they are.’
million US$ a year
The Value of a Whale Shark
Since 2016, IUCN describes the whale sharks on its Red List as Endangered. The reason is the demand for shark fins in Asia and the nature of whale shark meat, often referred to as ‘tofu shark’. Infuriatingly, despite their size, they also end up as bycatch. Since early 2017, whale sharks enjoy protection as migratory species in more than 125 countries. A number originating from research in 2004 estimates their value to tourism at over USD 47.5 million a year – an amount that is indisputably higher today. Hopefully, governments will realise the species’ importance and enforce the protection they committed to.

Photograph © 2011 Josef Litt
The Whale Sharks’ Birthplace
Members of the Galapagos Whale Shark Project in 2014 reported sightings of 27 whale sharks, all females, all but one pregnant around Darwin Island in the Galapagos archipelago – this seems to be a typical situation confirmed by tourists’ observations. Jonathan R. Green, the leader of the Galapagos Whale Shark Project, explores a hypothesis that the deep sea surrounding Darwin Island serves as a breeding ground for whale sharks. However, nobody has ever seen a whale shark to give birth or breed.
I heard a fisherman speculate about the reason why the whale shark males avoid the Galápagos. Their little cousins, the silky sharks, frequent the islands waters in search of food. Remoras belong to their favourite staple. An attacked remora would hide among the whale sharks’ claspers to protect itself. The ferocious silky shark will hardly differentiate between a remora and a clasper. The poor male whale sharks are afraid that they may get hurt in such a sensitive place, so they avoid Galápagos at all cost. I wonder whether there is a scientific base to this speculation.
Photograph Simon Pierce https://www.simonjpierce.com.
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