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Posts Tagged ‘eggs’

Have sex and die – the octopus way!

When I visited Lembeh in September/October there were flamboyant cuttlefish around in numbers that I have never seen before. On more or less every dive, we saw one or more flamboyants. Blue ring octopus were not as common, but still there was hardly a day when we didn´t see them. This is very much in contrast to the situation now, at least considering adult octopus and cuttlefish. We have seen some, but while still here, they are not nearly close to the densities experienced in September/October. Where did they all go?

A surviving flamboyant cuttlefish, that probably was out of luck mating in September

A surviving flamboyant cuttlefish, that probably was out of luck mating in September

Actually, cephalopods, the group that octopus and cuttlefish belong to are quite short-lived. Not only that, they only reproduce once and then die! This pattern of reproduction, where an individual grows for almost all its life, mates and then die, are called semelparity.

Mating coconut octopus in lembeh

Mating coconut octopus – not something they will do a lot of times!

Other animals continue living after reproduction and produce other litters some time after. Such a strategy, with multiple reproductive events after the onset of maturity, is called iteroparity.

Giant frogfish, an iteroparous species mating several times during its life cycle

Giant frogfish, an iteroparous species mating several times during its life cycle

The answer is that all life histories, that is the allocation of energy over time, consist of trade offs. Food is seldom unlimited, and if it where, time or developmental rate would limit the options available for an animal. The first ting that needs to be realized is that reproduction, having offspring, is expensive. Experiments have time after time verified that reproducing individuals of a lot of different species die earlier than non-reproducing individuals. That is the first trade off, choosing between a long life or offspring. And having no offspring is a fundamental screw up in nature, as your genes get lost for the future, so choosing long life rather than reproduction is not an option for animals looking for success in life.

Hairy shrimp carrying eggs

Hairy shrimp carrying eggs

The second trade off is that costs are related to the effort that is put into reproduction. Everything else equal, the more offspring that is produced, the less survival or future growth rate an individual will experience.

Baby broadclub cuttlefish that never will meet its parents!

Baby broadclub cuttlefish that never will meet its parents!

The third important trade off is that an individual need to keep significant amounts of energy reserves in order to survive over long time in the future. Up to around 90% of the energy budget might have to be allocated to future survival if that is the goal. Thus, an individual can produce a vastly higher amount of offspring in one reproductive event if no energy is saved for future survival. Thus, if an individual irrespective of reproduction faces quite high mortality rates, it could obviously be advantageous to “go all in”, reproduce with all the effort you can, and save nothing for a very uncertain future. And that is exactly what cephalopods do, invest all they got in one single “big bang” litter instead of saving themselves for another day.

Young blue ring octopus

Young blue ring octopus

The cool effect of that here in Lembeh is that there now are quite a number of minute, fully colored flamboyants around. The young flamboyants are really cool, brightly colored and have a lot of attitude.

Newly hatched flamboyant cuttlefish

Newly hatched flamboyant cuttlefish

Blue Ring Fever Reaches a Climax

Blue Ring Octopus have been everywhere form months now, which is unusual to have them around for so long.  The guests have seen them mating, feeding, fighting and now we saw a beautiful specimen with eggs.  Blue Rings doing normal behaviour are a Top 10 Critter for Lembeh, where would you place one with eggs?!

'Pregnant' Blue Ring Octopus carrying Eggs

‘Pregnant’ Blue Ring Octopus carrying Eggs

Blue Ringed Octopus have a life cycle of 2 years, however, for this female her time is nearly up as once the eggs hatch she will die.  She will not have eaten for the entire pregnancy (which lasts around a week to 2 weeks). This beautiful girl has moved away from where we found her, hopefully to live out the rest of her days in peace without any photographers! Hopefully in a few months we will start to see her offspring out feeding.

This was a first for me and as such the video is probably not as clinical as it normally would be.  I also left the clip in of the Octopus leaving the bottle without being abused.. Although to be honest I am sure he would not have left the bottle if there were no divers around.

Banggai Cardinalfish

Banggai Cardinalfish, juveniles in mouth

These days our Guide Aso is taking the Krueger familiy from the Netherlands diving. Today they decided, that they would like to see Banggai Cardinalfish. So we went with their boat to Police Pier 2 and planned the dive to have more time in the shallows just under the pearl farm jetty … there is a big Anemone with hundrets of Banggai Cardinalfishes. We spend a good 25 minutes just watching these beautiful fish gathering around their Anemone. There were even several ones with Eggs and also some with hatched babies intheir mouth. The Banggai Cardinalfish incubates the eggs in the mouth for 20 days and then keeps the hatched babies for another 10 days.

Velvet Ghost Pipefish Couple

A few week ago i posted about a white Ghost Pipefish, which i believed was a Halimeda Ghost Pipefish. I was already not sure at the time, but when revisiting the spot yesterday, i saw that i was wrong. It turned out, that it is a Velvet Ghost Pipefish – which is also a very rare fish. But even cooler is, that there are now two of them. The bigger one – the one that we have seen previously –was a male before. But when coming back this time it already turned into a female. Probably the arrival of the smaller male made it change sex. Ghost Pipefishes can change sex and turn into females. They can be recognizes by the pouch shaped pectoral fins in which they then keep their eggs. Unlike Seahorses and Pipefishes, where the male incubates the eggs, it is always the female Ghost Pipefish, that takes care of the unhatched eggs.

Things on sponges

Lembeh Strait is a Muckdiving paradise – and it has many interesting habitats to offer. Algae, Sand, Rubble, Coral, Rocks and Sponges. This week i took 3 nice photos with different animals all living on the same type of sponge – i just realized that, when going through my pictures of this week. There are many other cool critters living on those sponges, but i just thought i share these that have been taken within some days.

There is a Paaron Shrimp, that really blends in with the sponge and not only mimics its colour and shape, but also its surface pattern. Then there is a sponge mimicing Nudibranch, that is laying eggs and a carrier crab that is decorating its back with a piece of xenia coral (polyps are retracted in this picture).

Creature Feature: Flamboyant Cuttlefish

The Flamboyant Cuttlefish (Metasepia pfefferi) is a member of the cuttlefish family – but a very untypical one. Unlike other cuttlefish it is not shy at all but displays it’s poppy colour signals to communicate the potential danger of the poison in his flesh to potential predators. This makes it really easy to observe and photograph the flamboyant cuttlefish. Another difference from other cuttlefishes is the fact that the flamboyant cuttlefish does not swim but rather “walks” on the sandy bottom using its mantle flaps and arms.

The smaller male fertilizes the eggs of the bigger female, that then lays them under objects like coconutshells, broken bottles etc. The eggs are round and the little cuttlefish often can be already seen inside the eggs. The hatchlings immediately display the typical colour after hatching and start hunting. The Flamboyant Cuttlefish is an excellent hunter that – like all cuttlefish – catches their prey with its feeding tentacles.

Best place to see Flamboyant Cutllefish in Lembeh Strait: Flamboyant Cuttlefish can be found on all Muckdive Sites in Lembeh. Eggs can be also found troughout the season as they reproduce year round.

Phototipps: 100mm or 60mm are both ok as the Flamboyant Cuttlefish is not shy – for photographing hunting scenes the 60mm is better though.

Eggs Double Feature

We had a fantastic morning today again with two beautiful dives here in Lembeh Strait – with a lot of things to see. Like for example Clown Frogfish, Ghostpipefishes in two colours, Ribbon Eels, Painted Frogfish, cool Nudibranchs, Gobies and Porcelain Crabs in Soft Corals and many other things. But my personal highlight was the “Double Eggs” Sighting – a Peacock mantis Shrimp and a Jawfish both carrying eggs!

The peacock Mantis holds the egg mass with her swimming legs for the whole incubation period and also does not feed in that time. The Eggs are Bright red in the beginning and get darker when it gets towards hatching. The Jawfish keeps the eggs in its mouth and (obviously) also does not feed while incubation. We can’t wait to go back an watch the eggs develop … and of course we want to be there when the little jawfishes hatch 😉