Since Duolingo decided to basically brick its app with the new 'energy' system that won't let you get through three lessons in a day, does anyone know any decent Duolingo alternatives?

Okinawa had its hottest September at 1.6C above the average. I filmed this mass coral bleaching last year, but didn't have the heart to share. Total annihilation of the first few meters of depth. This stuff happens before our eyes, and yet people who think it isn't real keep gaining power.

Yajaagama cave: Turning back at the clearing and heading out.

Yajaagama cave: Human bones. The cave is a historical burial ground with many broken urns. The remains are placed in several places, like the clearing at the end. Apparently the locals are fine with leaving them be.

The exit of Yajaagama. You're supposed to turn around at this clearing, although the cave actually continues just beyond it. You can see that this clearing was once part of the cave that has collapsed.

Parts of the cave look like it's melting. The dark specs here are inse.. cts.A species or subspecies of cave cricket (クメカマドウマ). These are one of the most common things in the cave, although I couldn't find much information on them.

Yajaagama cave: Close to the exit, there were this endemic subspecies of ground gecko, Goniurosaurus kuroiwae yamashinae. Beautiful stripes.

Yajaagama cave: Parts of the cave have glittering minerals. Sometimes they form beautiful little terraced pools.

Yajaagama cave: In many places it looked like there were veins of gold or some such mineral, but up close they turn out to be growths of lichen, covered in little droplets of water so they glitter.

Yajaagama cave: The ceilings were the domain of the oogeji (Thereuopoda clunifera), a type of centipede. They are about 10cm long I think. Never seen ones this huge, or so many. It's not one of the endemic species however.

Yagaajima cave: This is a species of land-dwelling isopod endemic to Kume, with distinct yellow spots. It has a Japanese common name but is a scientifically undescribed species (Ligia sp.). Here in the cave it is 800m away from the closest seashore, where isopods of this genus are usually found.

Yajaagama, a cave on Kume Island. Supposed to be 800m long and closed off at various points, some areas for bat conservation, some because they are unsafe. Filled with endemic wildlife, darkness, and human bones.

The footage quality is poor, but this is a rare Rhina ancylostoma, bowmouth guitarfish, seen in Oura Bay (Okinawa), where they are building a new US marine corps base. It's a type of ray. I've never seen one in the wild before!

Rain and rainbow

Sneaky stonefish.

I was looking at the many orange sponges in area thinking 'it would be cool if one of these was a frogfish'. And one of them was.

An Octopus cyanea - when you are at your most beautiful when you are barely visible at all

Excited to share our study on sailing siphonophores, AKA bluebottles or man-o'-war! 🌊 we received hundreds of samples from scientists around the world, part of a huge effort to sequence genomes and test for multiple species 🧬 out today in @currentbiology.bsky.social doi.org/10.1016/j.cu... 🦑🧪📌

Cathedral sunbeams

A marbled stingray foraging at dusk, having come up from the deep as soon as the sun started to set

A sea elephant (heteropod) flapping its lazy way through the night. Something about the motion of its fin is weird and hypnotic.

A polychaete worm jives with a solitary dance number in the darkness

Returning to land at sundown, sometime last year

Among a dreamlike seascape of copepods and jellies, a rare heteropod (sea elephant)! Despite looking like the ghost a of a vengeful banana, with beady eyes and a long proboscis, they are a type of pelagic snail. Fin on its belly is its 'foot'.

A hypnotic flatworm flowing through the night

Bobtail squid (Eumandya parva) in the darkness, looking like it's ready to start a tiny, tiny fight with someone

A cautious Amphioctopus, not quite sure what to make of our lights

This rock is restless

A rare (for my area) Amphioctopus encounter at night

Sunbeams in the only cathedral I attend

This bubble snail decides to bother a clam and is blown away

A post dive sunset

An Octopus cynea showing off a quick flash of camouflage

The sand grains are running away I think they are a type of tiny hermit crab, but going through the footage honestly I'm not sure.

Benthic ctenophores (comb jellies) neatly perched on the spikes of a sea cucumber

A slight misalignment among the order - a half transparent shrimp camouflaged against a hydroid

Views of the beautiful Fukui coast, from a trip two months ago. Snorkeling here one summer as a kid, it was the first place I ever saw a squid in the wild. Part 1/3

Who's the cooler roommate? Peeked into an octopus's den and found that it's sharing lodgings with a blue-striped pipefish (Doryrhamphus excisus) couple

Sea moths - very strange and adorable little fish

An encounter with an aka-ika (red squid), the largest of three members of the Sepioteuthis lessoniana species complex and the rarest to see close to shore. It kept coming back to this one rock for some reason. It's not for laying eggs (not the right substrate and no eggs there since this encounter)

A fortress of hidden monsters. This large, cavernous, coral-encrusted rock in the middle of a barren zone had something like 9 stonefish hidden about the place. A deceptive oasis for the many little fish that take shelter there.

A scorpionfish on the move... Sneakily. So no one sees

Adorable fuzzy frogfish, a tiny predatory muppet

Last week I had the opportunity to dive in Oura Bay (in Okinawa) for the first time. Acros from where they are burying the reef with a landfill to make way for a new US military base, there is a astounding reef of Heliopora. The photos don't do it justice - like a vast miniature megacity of spires.

This unusual nudibranch was drifting in the current (which is not rare per se for nudibranchs) and I managed to get it to land on my dive torch. It seems like it can unfurl itself dramatically to catch the ocean current, drifting away again

I've always liked the way porcelain crabs look, with the large claws for defense but separate fan-like 'arms' for catching tiny particles of food. They are not true crabs, but an example of carcinisation, a phenomenon where separate lineages of crustaceans evolved independently to look like crabs.

Little juvenile squids, like little sprites just under the surface

The forest of spikes that is the surface of a crown of thorns

After the three stingrays tire of playing, one spontaneously disappears into the sand and the others disperse.

I was starting to film one stingray, then a second stingray came out of frame and started annoying a third hidden stingray out of the sand. Then the three stingrays start messing around. Individually these are not rare but it's so delightful to a group of them playing (or courting)