A Picture Tells a Thousand Words
Photography has never been so accessible; the development of camera technology in our phones and the affordability of professional kit means more people than ever can take amazing photos. But did you know…for decades photos have been a fundamental resource in driving forward our understanding of whales and dolphins.
Individual whales and dolphins can be identified by unique markings on their bodies; dorsal fins and tail flukes can display identifying features such as nicks, notches, and distinctive patterns. Photo identification, or Photo-ID, is a tool used by researchers to identify individuals and, importantly, pin them to a specific place in time. Over time, each individual whale or dolphin is added to a catalogue and any subsequent re-sighting of the individual is recorded. This non-invasive research technique is crucial to deepening our understanding of species - both at individual and population level. So, what can we learn from a photograph?
POPULATION SIZE
It goes without saying, quantifying a population size is critical for conservation – knowing how many individuals make up a group, we can ascertain whether it’s a healthy size or not. Through Photo-ID, the numbers of bottlenose dolphins, killer whales, Risso’s dolphins and minke whales found off Scotland’s west coast have been quantified. The west coast of Scotland is home to a critically endangered community of killer whales called the West Coast Community. We have been monitoring this group since we established and in recent years only two of the males – John Coe and Aquarius – have been recorded.
The instantly recognisable dorsal of John Coe
SPECIES RANGE
How far do animals travel and where do they migrate to? In many cases we still don’t know the answers but through Photo-ID we are starting to unravel these mysteries. Humpback whales are usually identified by their tail flukes; however, one individual Barney is also recognisable from his dorsal fin – which has a distinct barnacle on it, hence the name! Barney has been spotted off both the east and west coast of Scotland – you can read more HERE. Through analysing photographs taken of humpback flukes, it’s thought in the eastern Atlantic a general migration is made between the Cape Verde Islands where the whales overwinter and calves are born, and feeding grounds in northern latitudes such as Scotland, Ireland, Iceland and Norway.
The patterns on a humpback’s fluke are as unique to individuals as as our fingerprints are to us
AGING INDIVIDUALS
Back in 2016, an amazing discovery was made…the killer whale who swam up the River Foyle in 1977 was none other than Comet – W05 in the West Coast Community. A fully mature bull in the late 70’s, this allowed us to age Comet at around 60 years old at the time! You can read the full story HERE. We had always speculated that members of the highly unique and critically vulnerable West Coast Community were older in age, this significant discovery allowed us to validate that suspicion.
Comet, photographed in 2007
SOCIAL INTERACTIONS
Many species of whale and dolphin are sociable creatures, with complex language structures, family bonds and differing cultures. Through Photo-ID we have learned that Scottish bottlenose dolphins are very sociable and there is overlap between different populations. Individuals from both the Hebridean and the Moray Firth groups have been found to visit and interact with each other, and bottlenose dolphins found off the Irish coast. Earlier this year, a bottlenose named Tyler (or Squiggle) was recorded off Appin. Tyler used to reside in the Moray Firth but took up residence in the Clyde a couple of years ago. In more recent months, Tyler has surfaced off the coast of Ireland! This is important as it means that populations aren’t existing in isolation, particularly vital for relatively small populations like the Hebridean community.
One of the ‘Hebridean’ bottlenose dolphins
SITE FIDELITY
Site fidelity is term used to describe an area where individuals return on a regular basis, you could say an area of importance. Through Photo-ID we know that some minke whales – such as Knobble and Kasey – return to the Sea of the Hebrides year-on-year to feed. Knobble was spotted in August this year, clocking up over 50 sightings, over the past 2 decades! The deep waters off the Isle of Lewis have also been identified as an important area for the Risso’s dolphin. Marine Protected Areas (MPAs) for both these species have now been allocated in those areas, with Photo-ID studies helping demonstrate the importance of these places for the animals.
Identifying species hotspots is vital to their protection
HWDT’s Minke Whale Catalogue has just been launched - documenting over 300 minke whales which have been recorded off Scotland’s west coast over the past two decades. This new digital catalogue is a key conservation resource which will have a significant impact on the understanding of minke whales in our seas and provide an excellent foundation for future research of the species.
One of the whales - Snowy - was found to be a European record breaker, notching up the longest sightings history of the species! Snowy has been returning to the Hebrides over a 27- year period. First recorded in 1994 and sighted 11 times since, the latest being in 2020.
This Minke Whale Catalogue is a vital research resource and is testament to the power of citizen science - the collection of data by members of the public. The data which underpins the research presented in this catalogue is collected by our Whale Track community and those who join us on board our research vessel, Silurian.
Anyone with a passion for protecting our marine wildlife can BECOME A CITIZEN SCIENTIST
If you live on the west coast of Scotland, work on Hebridean seas or are visiting the area, please consider joining our Whale Track community and record your encounters (extra points if you take photos!).
Anyone can take part in our research expeditions on board Silurian, all that’s required is a willingness to learn and get stuck in with all aspects of the experience. Explore the waters off the west coast of Scotland during our live-aboard expeditions, help protect our wonderful marine wildlife while having an unforgettable experience. 2024 expeditions are available to book now, but filling up fast!