Jellyfish - Cnidaria

Gelatinous umbrella shaped bell with long tentacles flowing underneath around the mouth. The bell for moving, and the tentacles for catching prey. This what we know as the jellyfish. In reality, they should be called Jellies because their body is nothing of a fish.
They're found in every ocean, from the surface, to the sea floor, the most colourful lurk around coastal zones. Theses strange creatures have roamed the sea for at least 500 million years, being the oldest multi-organ animal alive.

A group of jellies is called a "Bloom", a "Smack" or "Swarm".
Jellies form in the same way as Anemones (almost like plants), but instead of staying clinging to the rocks, they have an extra phase of their development and are released into the open sea to swim around.

There are problems around the world in places where either global warming has killed the jellies' predators, or over fishing has had the same effect, causing the jellyfish populations to increase so greatly that it's dangerous to swim, and they're taking over the seas.
Smallest Jellie, Irukanji Jellyfish, is around one millimetre and the largest, Lion's mane jellyfish, is up to 2 metres in diameter.
Most have lethal stinger on their tentacles, but a few, like the moon jellyfish that's commonly found around New Zealand, won't sting if you were to pick it up.

They're strange little critters, but somehow extremely fascinating and gracious.

Crabs-Brachyura

These aren't the ones you find in spiral shells (hermits), the creepy ones with massive claws (porcelain), the crazy soldier like crustaceans (horseshoe), or the microscopic critters that live in pubic hair (or any course hair). These are the true crabs.

They have a thick external skeleton, two claws, live in the ocean, fresh water, and tropical land.

They can be a few millimetres wide (the Pea Crab), or up to 4 metres wide (the Japanese Spider crab).

Males have larger claws and a skinnier, pontier abdomen pouch on their belly, the female's is wider so she can fit her eggs in it whilst fertilising.

Crabs tend to mate belly-to-belly, and attract each other through hormones, dances, vibrations, or sounds.

They usually mate soon after the female has moulted her shell and is still soft. She can store the sperm for a long time before she choses to fertilise it.

When a female is carrying eggs, it's called "berried" because the eggs resemble little berries.

Throughout a crab's lifetime, it will moult many times. It's old shell starts to erode around it's body, while the new shell starts to form underneath. The crab will absorb large amounts of water to crack the old shell and spend hours if not days removing every part of it's body from the old shell. If it gets stuck, it has no chance of survival. 

After releasing the shell, it hides until the new shell it hard enough for protection.

They walk sideways because of the way their legs are laid out, but some can walk forwards and backwards, some can swim, like the paddle crab, who's back legs are flattened into little paddles to help.

Crabs make up 20% of all crustaceans caught by fisheries, and about 1 1/2 million tonnes are caught each year.

Pretty Sad.

In the weekend, a Sperm Whale was found washed up near the Taramakau River mouth, south of Greymouth and on Saturday a Cuvier's Beaked Whale was found at Cobden Beach, also near Greymouth.

The Sperm Whale was about 17 metres long, massive.

When animals that large have lived in water their whole life, and have a body made to work with the support of dense ocean, being out of the water doesn't support their large bodies and their bones and organs can't withstand the weight of their huge body mass. That's why most beached whales don't stand much chance of survival.

 You're probably interested in why they're called "Sperm" whales, it's not what you think. Their heads hold a huge quantity of a substance called spermaceti, which is what the early whalers found when they started hunting this species, and they somehow came to the conclusion that it was the same as human semen, hence the name. But they later realised that this liquid was extremely valuable for cosmetics, candles, waxes etc. Which then started a big craze towards whaling for Spermaceti.

They're the largest of the toothed whale group and have the largest brains on earth. 

Both the species of whales found tend to hunt for squid-like creatures around 1,000m deep and both are spotted around New Zealand quite often.

It seems to be a common event , finding beached Cuvier's Whales, but the loss of the Sperm Whale is pretty miserable, there aren't thaat many left and we need to take care of them!

(A wee video showing the gentle heart of Sperm Whales and the opposite of the Orca) Orca vs Sperm Whale