21 Apr 2018

21 Apr 18 - Atlantic Odyssey - Day Twenty Three: A Magical Encounter With Sperm Whales

The previous Post covered the Seabirds & Flying Fish seen on the first full day at sea on the crossing between St Helena & Ascension Island. However, the highlights of the day were to be the Cetaceans. It all kicked off before breakfast when we picked up some distant large Whales well in front of the Plancius on the starboard side. Due to the blows these large Whales could often be picked up from the bridge wing at two miles or more away. This then allowed us time to get people onto them, albeit it might be five to ten minutes before we finally drew level with them. In this time, they may have crossed the bows if moving at right angles to us or dived. We seemed to see a larger number of large Whales in the first hour of light than in any hour of the day & I wonder whether some were just in the same dozy & less active state that many humans are when they first wake up.
Sperm Whale: A typical sighting of one of the distant blows. Marijke said it looked like a Sperm Whale as they have an unusual head with their blowhole on the left side of the head & tend to make low, lop-sided blows
Sperm Whale: A harsher crop revealed a large-bodied Whale surfacing
This was our first Sperm Whales on the Odyssey. The Expedition staff were discussing with the Plancius's crew whether it would be possible to change course, but the Sperm Whales were clearly hungry & food was on their mind. It was also on our minds, but breakfast didn't start for another half hour.
Sperm Whale: Unfortunately, three minutes later when we were still quite distant, they decided to head deep for breakfast
Sperm Whale: When you see the tails of large Whales, it's a sign they are starting to dive
Sperm Whale
Sperm Whale: That's the show over for the next 30 minutes or more. When they dive they typically dive for 30-45 minutes & are believed to feed around 400 metres. However, they have been found to dive as deep as two kilometres & stay down for up to two hours. They would have been at least five or more nautical miles behind the Plancius by the time they resurfaced: at which point they wouldn't have been visible (not least, as we were heading off for breakfast)
Fortunately, this wasn't the only Sperm Whale party we saw during the day. A second party were found around 11:00 & this party were more showy. They were making shallow dives, but quickly returning to the surface. The Captain was happy to slow & manoeuvre to allow us to enjoy a superb Sperm Whale encounter which lasted near an hour from our initial sighting. It is believed there were eight Sperm Whales in the party & Marijke said that there were likely to be females and youngsters as the males tend to only join these parties for short periods.
Sperm Whale: As with the earlier sighting, it all kicked off with an initial set of distant low, lop-sided blows
Sperm Whale: However, this time the Sperm Whales were in no hurry to dive. The Plancius is such a quiet ship that she doesn't disturb Cetaceans on the surface when she slows, turns & carefully approaches surfaced Cetaceans
Sperm Whale: As the blow disperses, the small dorsal fin appeared
Sperm Whale: As the dorsal fin appears, the head had already disappered
Sperm Whale: Another sighting
Sperm Whale: A close up of the head from the last photo showing the off-centred blowhole
Sperm Whale: This is a different individual with a poorly pronounced dorsal fin & is presumably an immature
 Sperm Whale: This individual must have twisted as it dived as this looks like the tip of a tail flipper
Sperm Whale: Preparing for a shallow dive
Sperm Whale: Showing the brunt head & offset blowhole
Sperm Whale: As the back of the head appears, the front of the head has already disappeared
Sperm Whale: Finally, the dorsal fin appears
Sperm Whale: This appears to be a different immature as it has several pale blotches close to the dorsal fin which appear in the same places on different photos (so they do not appear to be splashes of water)
Sperm Whale: Another individual blowing as it surfaces
Sperm Whale: The same individual
Sperm Whale: A close up of the asymmetric blowhole
Sperm Whale: As the previous individual fully surfaced, it had a very distinctive pale dorsal fin
Sperm Whale: A close up of the distinctive pale dorsal fin
Sperm Whale: A younger individual surfaced next to the white finned individual
Sperm Whale: The dorsal fins of the two individuals
Sperm Whale: Both individuals resurfaced & blew together
Sperm Whale: Females can grow up to about 12 metres & the largest males have been recorded at 19 metres long
Sperm Whale: A final individual with small notches in the dorsal fin
It had been a brilliant hour & finally the Captain decided we needed to get moving again.

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