Wildlife & Railway Art - Frédérique Lucas

Colour anomalies in the Short-beaked common dolphin (Delphinus delphis)

As some of you may know I’ve a bit of a weak spot for everything weird with cetaceans: hybrids, deformities, colour anomalies - I love it all. And Short-beaked common dolphins are a gold mine in that last department. I don’t think any other species displays quite so many different anomalies, and with such frequency, as this one. Some, like the melanistic form, are almost ‘normal’ and quite stereotypical in their presentation. Others, like the dolphins in row 4, are highly unique. So earlier this year I made this poster documenting all know anomalies - initially just for fun but I ended up quite liking it! I hope you’ll have fun perusing the oddities of Delphinus delphis too. 

Most of these are based on several animals with similar anomalies. However, since the animals in row 4 are all so unique, here’s specific credits to their spotters: 4A was an individual stranded in the UK; 4B, D and E are all photographed by Lisa Steiner of Whale Watch Azores; 4C by Capt. Dave’s Dolphin Safari, 4F by Marilia Olio, and 4G was published in this article here.

DOLPHINS OF A DIFFERENT COLOUR (bonus)  Here’s a little bonus piece to the odd dolphins watercolour series. It’s actually the first one painted, but since it’s kinda rough around the edges and doesn’t fit with the later chosen design I didn’t want to upload it with the others. It’s a really cute fella though so I didn’t want to hide him forever! This shy ghost too is available. Watercolour on hot-pressed paper, 14.8 x 21 cm like the others. Message me if you're interested :)

• the Haviside’s dolphin who lost his dorsal overlay • Cephalorhynchus heavisidii - Just like the short-beaked common dolphins, one Haviside from Namibia seems to have lost his dorsal overlay. As a result he still has his dark cape, but the grey base is missing from the rest of his body. Some dark patches remain around his eyes and on his chin, but other than that he is a very light off-white. However some grey lining still persists around the truly white belly markings, allowing them to stand out. Interestingly, unlike the ‘clean’ common dolphins, the remaining colouration is blotchy and spotty, especially around the edges. This is a feature that shows up more often on dolphins missing part of their colouration pattern.

DOLPHINS OF A DIFFERENT COLOUR Lately I’ve been painting odd dolphins. Abnormally coloured cetaceans have long fascinated me, and I though mirroring them with a normal conspecific was a pretty cool way to show some off. All of these are real and have been seen in the wild, their markings the result of a genetic anomaly. These guys are also for sale! Message me if you want to welcome an odd dolphin into your home :)  All are watercolour on hot-pressed paper, 14.8 x 21 cm.

• the short-beaked common dolphin who lost her dorsal overlay • Delphinus delphis - Short-beaked common dolphins are perhaps the species most frequently observed with anomalous colouration. All sorts of fun things can happen. Like many dolphins, their markings appear to consist of two overlapping systems: the yellow ‘cape’ and the grey ‘dorsal overlay’, where the two meet they form black. In some rare cases the dorsal overlay disappears, leaving only the yellow cape. It provides a fascinating insight into the make-up of their markings. Often these dolphins have little bits of overlay remaining at both end of their body, explaining the grey tail and dark facial markings. In some the normal-coloured parts are wider, leaving a yellow-and-white band in the centre of the body, while others have no black at all.

• the long-beaked common dolphin who only kept yellow • Delphinus capensis - Interestingly, long-beaked common dolphins are never seen with a missing dorsal overlay. Instead they show a different mutation with somewhat similar results - which in turn is never observed in short-beaked commoners. If we may apply birding terms, these animals seem to be leucisitc. Leucism completely inhibits the production of melanins, resulting in a white animal. The eyes remain a normal colour. The common dolphin’s yellow patch however is likely produced by a different pigment (e.g.  carotenoids as in birds), unaffected by leucism. As such, they retain the shape of their normal markings, but only the yellow is visible. Leucism need not be complete: sometimes regular-coloured patches remain, and leucistic long-beaked common dolphins often have these in the form of black spots on their back.

• the dusky dolphin who turned ebony • Lagenorhynchus obscurus - Dark dusky dolphins like these have been seen a few times around New Zealand. They show a form of melanism: an abnormal deposit of melanin in the skin, often - but not always - resulting in a darker animal. This can take on many forms, such as increasing the spread of dark markings (like a tiger with merged stripes, which is sometimes called ‘abundism’). However in these duskies the markings remain intact but so much melanin is produced all over the body that they become harder to make out. They also appear more brownish than their normally coloured counterparts, possibly indicating an increase in pheomelanin (brown pigment) production.