Long finned pilot whales, Globicephala melas, are one of over 20 species of cetacean that can be found in Icelandic waters. There are around 35,000 individuals here. At Elding, we have seen them from both of our locations for whale watching tours, in Faxaflói and Eyjafjörður. In recent years this cetacean has been coming very close to Akureyri harbour. When they have arrived here the pod has encompassed calves. It is thought they are coming here as it could be safer with calmer seas in the fjord, no predators and reduced boat traffic. So, in this blog we thought it would be exciting to investigate this species in more detail and find out what makes them unique.
Long finned pilot whales with Akureyri in the background. Photograph taken by Babsi, 2021.
Starting off with some key details regarding long finned pilot whales. Individuals have dark coloured skin with long pectoral fins. They have bulbous melons; the melon is an organ made of fatty tissue that is used for communication and echolocation. As with other odontocetes (toothed whales) the males are the larger sex. The males reach up 7.6m in length in comparison to the females reaching 6m. This makes them the second biggest species of dolphin in the world, behind only the orca (killer whale). Males also weigh up to 4500kg with females only getting to 2500kg. Females do however live longer; their life expectancy is 60 years which is 15 years longer than males. Long finned pilot whales also tend to live offshore in deeper waters. They can drive for 10-15 minutes to around 600m deep to find their food, mostly squid.
A pilot whale spy-hopping, showing off the large melon. Photograph taken by Babsi, 2021.
Long finned pilot whales are very social and therefore live in large pods. Usually, there are up to 20 individuals in a pod but there can be up to a thousand. These pods are usually led by a matriarch and family based. Therefore, when pods come together, and they have hundreds of individuals it is the perfect opportunity to mate with individuals from other pods which would help keep the gene pool strong. With females having a longer life than males it may suggest they go through menopause. But unlike short finned pilot whales, these long finned ones do not. Despite this, older females, when not breeding, will still care for calves within the pod. This is an example of alloparental care. Overall, though, these individuals have incredibly strong bonds to each other. However, this can have consequences. Mass strandings are quite common as if one individual gets into trouble there is potential for this to happen to the rest of the pod. This closeness also makes them more susceptible to whaling. Pods can easily be herded together making them easier to hunt; in the Faroe Islands around 700 individuals have been killed each year since 2017.
Mass stranding of long finned pilot whales on Gamlaeyri Island, West Iceland. Photograph from https://oceanographicmagazine.com/news/pilot-whales-iceland/
Around Iceland in recent years there have been very cool sightings involving long finned pilot whales with orcas. These interactions between these species are usually happening in Vestmannaeyjar and Breiðafjörður. During these sightings it is very common to see the pilot whales chasing the orcas at high speeds. Currently, the main hypothesis for why this may be happening is that is could be an anti-predator behaviour called mobbing. The pilot whales will harass the orcas to stop them from any potential attacks. In Norway when the pilot whales hear orcas their pods will increase in size as they get closer to the orcas. To confuse matters further, there have also been sightings of orcas with long finned pilot whale calves. When these sightings have occurred the calves don’t seem to survive long as when the orcas were next seen the calves were missing.
Female orca with a pilot whale calf. Photograph taken by Marie-Thérèse Mrusczok from https://nyr.ruv.is/english/2023-02-27-killer-whale-adopts-or-steals-pilot-whale-calf
Due to the increase in sightings close to Akureyri in recent years at Elding we have started to investigate the pictures more closely through photo identification. From doing this we can identify if the individuals are coming back each year and try to learn more about the social networks within the pods we are seeing. So far individuals analysed in 2019 and 2021 have only been seen in one year. For example, some individuals have been in different months in 2021 but they were not seen in 2019 as well. Maybe different pods are having the same ideas of coming into the fjord.
By Rob Hyman
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