Whales, Wildlife & Wilderness                                                                                                                                                 Pam & Wayne Osborn

Sperm Whales - New Life

 

Wrinkled Baby Giants in a Wine Dark Sea

 

The breeze sharpened. A short chop slapped against the bulky grey-brown bodies. Sharp exhalations pushed against the wind but were soon dissipated by its gathering strength. Night was closing and the pod turned towards the distant shore. Not that rough water would be of any concern to these leviathans.  Sperm whales plough all seas from polar cap to polar cap. But tonight was special; the two cows were broad of beam and their wide bodies wallowed as they crested through the breaking seas. New life was in the offing.

 

In the wind shadow of the volcano Pico close to the jagged edge of the lava flow, the pod gathered.  Primal instincts had driven them to sheltered waters and within the protection of a marguerite (flower) formation, two calves were born.

 

They were not alone. Other eyes were watching.  Habits of a lifetime don't necessarily fade with retirement and the pod's movement inshore had captured the attention of the old whalers in the hamlet of Sao Caetano.  What was once a long Azorean tradition and livelihood stuttered to an end in 1987 when the last sperm whale was harpooned off this same southern coastline.

 

In the blood stained waters, each mother gently nuzzled her calf to the surface for its first breath.

 

A slight swell rolled into the harbour at Madalena as dawn broke the next morning. Our 8.5 metre rigid inflatable strained at the mooring lines as we heard the news of last night's births from Sao Caetano.  Our vigia (whale spotter) Anteiro lives in the village and his breathless rapid fire VHF transmission urged us to put to sea.

 

Perched high in his lookout on the volcano's slope, Vigia Anteiro had tracked the pod since sun up.  The whales had moved about 6 nautical miles offshore and had begun a slow trek eastwards.  It was from these spotting stations that vigia's efficiently guided the whaleboats to their quarry a generation earlier.

 

The seas had calmed and the caldera of the Pico volcano stood in sharp relief in the crisp early morning light as we sped towards the pod's location.

 

We had no anticipation of getting close and sat at some distance from the pod as we had no wish to disturb them.  The whales had other ideas and swam across to our boat.

 

Three male escorts - probably teenagers accompanied the two mothers and the two newborn calves.  These images show the pod passing by.

Learning to Dive

 

The calves swam with short jerky hobby horse motions. They were yet to attain the grace that comes with long practice. They thrust their blowholes well clear of the water to gulp precious air.  At this age they have limited dive capacity - a few minutes at best compared with the 45-60 minutes adults typically spend on deep foraging dives to depths of over 2000 metres.

 

In these three images a calf anxiously follows its mother down on a shallow dive.  When the mothers departed on long foraging dives, the three adolescent males acted as baby sitters.

 

The vertical lines or creases on the calf's side are a legacy of being folded up in its mother's womb.

Time to Suckle? - Not Just Yet

 

In these three images a thirsty calf tries to suckle as the mother begins to dive.  This impatience is understandable, but enthusiasm and inexperience has over-ridden common sense.

 

Sperm whale suckling has rarely been directly observed or filmed and there has been much conjecture as to the technique needed given their unique lower jaw structure.

 

An unconfirmed theory has evolved that calves may suckle through their blowholes.

 

This attempt is unsuccessful as the mother continues with the dive, however this calf is a quick learner and the next series of images reveal the secrets of how sperm whale calves suckle.

Sperm Whale Suckling Secrets Revealed

 

These two images reveal the secret of sperm whale suckling. Once she was down about ten metres, mum rolled on her back. The calf lay on its side against her belly and opened its jaw.  Two mammary slits are located on either side of the genital slit.

 

The calf was now rewarded with ropey strands of fat-rich milk. Suckling is also a great incentive for stretching breath hold capability as the calf can only feed when its blowhole is submerged.

Sperm Whale Milk

 

In the top image, a strand of milk can been seen behind the mother's flukes. The calf has stopped suckling and the pair are slowly moving on. The next image shows the ropey texture of the fat-rich milk which doesn't mix readily with the water.  Again this gives a clue to suckling behaviour as the expressed milk can be extracted directly from the water.

A sperm whale and calf on the surface

A male sperm whale and calf on the surface