A recent chat between long-time Lamu resident Louis Van Aardt and Wildlife Conservation Society marine mammal expert Tim Collins revealed a momentous marine occurrence.
On March 18, 2005, the Lamu fishing community and Van Aardt chanced upon a strange-looking stranded whale floating listlessly in the shallow waters opposite Kizingo Lodge on Lamu Island.
The distinctive rusty brown 30-foot long whale with what appeared to be two tusk-like teeth at the tip of its lower jaw was an unexpected sight for all present.
Fortunately for the disorientated animal, help was at hand as over 15 people manoeuvred the 2,300kg whale into deeper waters from where it swam off. The photographs that were taken were preserved for posterity.
These old photographs have created new excitement – it turns out that the bizarre-looking marine was a Cuvier’s beaked whale.
“The Kenya Marine Mammal Network (KMMN) is pleased to announce a 25th species of marine mammal identified in Kenya, Cuvier’s beaked whale,” stated KMMN’s Michael Mwang’ombe who has headed a group of whale and dolphin reporters in Kenya since 2010.
He added: “Beaked whales, a remarkable group of deep diving species, have been recorded in Kenya before; Longman’s beaked whales have been sighted in northern Kenya and a stranding of a dead Blainville’s beaked whale at the Sabaki River mouth, originally mistaken for a hippo, was reported in 2004.
“We were keenly waiting for a report of a Cuvier’s as they are the most widespread species of this remarkable family.”
Extremely important
Today, reports from fishermen and other marine users are treated as extremely important to establish the species of dolphins and whales in Kenya and their whereabouts
“We know very little about these whales in Kenya as they are found in deeper waters,” continued Mwang’ombe, “but this is a fantastic rescue story in itself with the Lamu community pulling together.”
He went on: “The message is that many fishermen and other ocean-goers have historical data to add to our (KMMN) catalogue of species. This is an opportunity for everyone to dig deep into the back of their cupboards for old photos, or raise that conversation you heard as a child of dolphins and whales in your area.
“There is a tendency to assume that we know everything and individual observations don’t matter, but with the KMMN the opposite is true. Every story or sighting counts.”
Although humpback whales were first scientifically recorded in a KWS aerial study in 1996 in Kenya’s coastal waters, fishermen had been observing them for 30 years, and started reporting to KMMN in earnest in 2010.
Whale-to-wildebeest migration
Today, Kenya is known for her whale-to-wildebeest migration spectacles between July and October, boosting the country’s tourist circuit.
In East African coastal waters generally, a total of 33 species of marine mammals have been recorded so far.
In 2006, Van Aardt saw another Cuvier’s beaked whale near Kinyka Island in the Lamu archipelago. Then in 2017 and 2021, KMMN received reports of two more sightings, but these could not be verified since there were no photos.
The Cuvier’s beaked whale is the most widely distributed of the beaked whales. Named for Georges Cuvier, a French zoologist, the species is found in deep temperate and tropical oceanic waters around the world.
The whales are deep-diving pelagic whales that inhabit offshore waters of all oceans. This species is the most cosmopolitan of all beaked whales and is classed as vulnerable (IUCN Red List) in some parts of the world. It is protected by several international and regional agreements.
They are considered the deepest-diving mammal on earth, and researchers in California have recorded at least one dive that went 9,816 feet (2,992 metres) deep and lasted 137 minutes. Subsequent work in New England extended the record for the longest dive by this species to 222 minutes (3 hours, 42 minutes).
In search of squid
The species dives to these great depths in search of squid, which they find using echolocation waves that are generated in the “melon”, the bump on top of its head.
Cuvier’s beaked whale is known to be extremely sensitive to underwater noise created by humans, and are particularly affected by some types of sonar. This makes noise the greatest threat to their existence.
Strandings have occurred in association with naval exercises where sonar may have been in use. In the Canary Islands, strandings of these whales stopped when naval exercises using sonar were banned. In the Mediterranean, strandings continue, with conservationists seeking a ban on sonar use.
Nevertheless, it faces the same threats like other marine mammals, including accidental drowning when caught in “ghost” nets and plastic pollution that is increasingly finding its way into our oceans and marine food webs.
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