Talking of marauding predators, I watched this cuttlefish cautiously from the safety of my crevice home. It grabbed a small fish with its long tentacles and I wondered who had been the unlucky victim. Before the cuttlefish jetted away, I saw a sea scorpion’s tail sticking out from its tentacles. That fish’s camouflage hadn’t deceived the superb vision of the cuttlefish this time, with fatal consequences! Sad to see I guess, but cuttlefish have to eat and better a sea scorpion than a tompot blenny, especially as sea scorpions can eat young tompot blennies too.
Since the baby tompot blennies have settled out of the plankton, three noticeable things have happened. First, they have taken on camouflage colours and now match up with their background quite well. Next, they have a bright blue ‘eye’ spot on the front of their dorsal fin which they can flick up; does it make them look bigger and scare away other fish? Lastly, their head tentacles are developing well and they look like ‘mini me’ tompots as they explore my reef.
They are only 20 – 45mm long at this time of the year (depending on whether they hatched from their eggs early or late in the summer) but they are just large enough to be spotted and photographed by Paul and Teresa. What always surprises them is how these youngsters are very bold and like to show off in front of the camera! Wouldn’t you expect little fish like these to be much more timid and hide in the small crevices away from marauding predators?
Take a look at my blog from last year 30th September 2015 http://www.bennytheblenny.com/blog/?m=201509 to see a video of two very small tompot blennies play fighting.
You’ve seen how my amazing my babies were swimming around in the plankton. The ones that managed to avoid being eaten and found enough plankton to eat have grown to around 2 cm long and have now settled back on the reef. The researchers are not sure how they find a good home reef. It may just be luck or something to do with them being able to recognise the smell of the area they hatched from. Some coral reef fish know which reef is home from the sound the waves make!
When my babies first settle they are quite colourless, but soon take on camouflage colours to help them match their surroundings. You can see that their head tentacles have started growing and their pectoral fins are just visible with some black pigment.
Thank you to the National Marine Aquarium Plymouth for their help in getting this photo. The NMA is an excellent place to see tompot blennies like Benny the Blenny and lots of other UK marine life.
This video shows tompot blenny larvae like my babies swimming around in the plankton. These ones are around 15mm long and Teresa thinks they look like baby birds because they are flapping their pectoral fins to keep themselves swimming up in the water. They power themselves forwards using their tails too. When my babies first hatched as larvae they had a yolk sac which helped them stay up but that has now all been used up so they flap instead. If you look closely at the video you will see, just under the babies’ bellies, that there are two blackish lines. These are their pelvic fins (equivalent to your legs) that have started to develop. My youngsters at this stage are not showing any signs of growing head tentacles, but these will develop by the time they settle on the seabed as little tompot blennies around 20 mm long in a few weeks time.
Thank you to the National Marine Aquarium Plymouth for their help in getting this video; it is an excellent place to see tompot blennies like Benny the Blenny and lots of other marine life in action.
For wonderful line drawings and descriptions of tompot blenny larvae, see this paper:
Fives, Julie. M. 1986 Blenniidae of the Northern Atlantic (revised) Fich. Ident. Plancton (172:6pp)
This blog has been written for children on the http://www.wildlifewatch.org.uk benny’s blog
Hey, this shows what my tompot blenny babies look like when they have left home, having hatched from those eggs that I’ve been guarding. Swimming among the plankton in the open sea, they are very sleek with gorgeous big eyes and are between 4 and 20 mm long.
When they first hatch they eat very small plant (phyto-) plankton and animal (zoo-) plankton, the youngsters grow quickly and are then able to eat larger plankton. Bigger fish larvae and jellyfish in the plankton are a real danger and my babies have to make smart evasive moves if they see they are about to be grabbed!
If you would like to find out more about plankton visit:
This photo was made possible by the National Marine Aquarium in Plymouth so many thanks to them. Paul, my underwater photographer, would never be able to spot and photograph one of my babies in the wild!
All my babes have now left my crevice home or ‘flown the nest’ as you like to say! I’m very proud of all my work because I was guarding eggs non-stop for nearly 4 months, keeping away all the ‘egg thieves’ (animals that might want to eat them) and caring for the eggs by wiping them over with my bulbous glands. Each batch of eggs takes about 2 months from being laid to hatching but, as we saw in my last blog, I had several batches! I’m keen to show you how wonderful they are closer up. This photo by Paul at the end of May showed that Belinda had just been laying the dark purple ones to the right of the picture. They were then the last to hatch in mid-July.
Now look at the eggs with obvious silver eyes at the front under Belinda’s eye, they were the most developed and were almost ready to hatch. In the middle, the gold coloured eggs were part way through their development and so had the different colouring. Can you see the amazing little cups they are laid in?
When the eggs hatch, the very small tompot blenny larvae swim up into the plankton and have to take their chances along with the young of many other sea creatures. Having batches that hatch at different times is a very good survival strategy for us tompot blennies. If one batch of our larvae get hit by bad weather or run into particularly voracious predators eating lots of plankton, there’s a good chance that the other batches will have an easier time.
I’m now looking forward to seeing as many as possible of my youngsters landing back on the reef after their tough time in the plankton!
When I’m guarding all the eggs in my crevice, I have plenty of time to watch them develop. Something I notice is how they change colour. You can see in blog 21/4 that when Brenda laid her eggs they were like perfect amethyst jewels, a lovely deep purple, stuck in a very neat honeycomb pattern on the floor of my crevice. As I cared for them, the viable eggs i.e. the ones that were healthy and that I’d successfully fertilised, developed from purple into beautiful golden globes.
Over the few weeks after that, they progressed so the baby fishes’ eyes could be seen shining silver. The eyes are large relative to the eggs, so part of the whole layer looks sparkly silver and it feels as though all the eyes are on me!! Because several different females have laid the eggs at different times (this is called partition laying), I am often looking after the three stages of eggs at the same time. Not at the moment though, it’s now the end of the season and I’m just waiting patiently for the last few sparkling silver-eyed eggs to hatch. Phew, I can then build up my strength again because being a ‘stay at home dad’ is very exhausting!!
This photo shows my friend Maisie being a Tompot girl. Thank you Maisie, I’m very proud to be starring in the July 2016 BBC Wildlife magazine. My underwater photographer Paul Naylor has written a fascinating article about me, my tompot blenny neighbours and the other colourful fish that live on my reef. The magazine’s the copy with the mugshot of the whiskery hippo on the front cover.
Although I have a good number of eggs to guard already, and I’m busy looking after them in my crevice home, females still visit me to lay more.
I usually have only one female visitor at a time (see blog 11/4/2016) but this time for some reason, I had three visitors all at once. The divers, Paul and Teresa were amazed; they’d never seen a male tompot blenny quite that popular before! Maybe it was because the special smells I waft out to attract females were particularly powerful or perhaps none of the other males on the reef have room for more eggs at the moment.
That’s me on the right; I’m slightly darker and redder than the visiting tompot blenny females – Beth, Bella and Brenda (yes, we can all be individually recognised see blog 24/3/2016). Luckily, they seemed to get on OK with each other, and I was certainly happy for all three to come in and lay their eggs. I was then very busy fertilising all those extra eggs. What a brilliant breeding season it’s turning out to be.
I’m keeping watch for predators and intruders. You can see from this video that I have unusual eyes and can look in different directions at the same time.
I’ve spotted something interesting. I’m off!