Nudibranchs are the favourite of many divers – especially in Lembeh where we have so many of them! This week’s ‘Creature Feature’ is the photogenic Bullock’s Hypselodoris (Hypselodoris bullockii) since their population seems to have exploded this past week with many sightings at the dive sites directly across the channel from our Two Fish Divers Lembeh Resort. It hasn’t been hard to find them this week and it’s also been interesting to see so much mating behavior and we’ve even watched them laying eggs. Nudibranchs give birth to tightly packed ‘egg ribbons’ which look like a tightly, woven fabric containing thousands of eggs each. These frail floral displays are easy to spot and the egg ribbon of this nudibranch is always yellow and spun in a neat spiral pattern.
As with most nudibranchs, Hypselodoris bullockii is brightly coloured to warn potential predators that it is toxic. The body colour ranges from a pearly white to a deep purple and we see both types here, although most sightings this week have been of the lighter coloured specimens. This nudi species feed exclusively on sponges and it is thought that this is where the toxins that make it so distasteful to other predators come from. Hypselodoris bullockii can be distinguished from other Hypselodoris species by the thin white line running around its foot mantel. In other species this line can be much thicker and often shows a gradual fade between the border and body colours.
It’s been another great week of muck diving for us in Lembeh, especially as we introduced Resya to her first muck diving experiences (and found some very special critters for her!) Congratulations to Resya for completing your PADI Advanced Open Water Course with Instructor Dan and a bigger congratulations for seeing a blue ring octopus on your first ever night dive!
Would you like to join us for Nudibranch, critters, and macro photography in Lembeh? We have the weirdest critters in the world and we love to share them! For more information, fill in the form below and we will get right back to you.
