Wolf Trap

One constant danger while you're fishing is the possibility of damaging or breaking your pole. So what happens to an angerlish if its pole is broken? Does it regenerate? Does anyone know? I'm curious because the wolf-trap anglerfish below looks to have such a complicated set of tackle protruding from its head.

We know why it's called an anglerfish. But why wolf-trap? It has to do with the shape and mechanics of the fish's jaw. The upper jaw is three times larger than the lower jaw, and it is able to open and close sideways. When in the ventral position, the upper jaw combines with the lower jaw and forms a compartment in which prey is held just prior to being swallowed. Think of a Venus flytrap. Or, think of it as a wolf trap.

Thanks for the anglerfish, Theodosia and Chris.

Photo source: Cracked.com

What do you know--another tragedy out of China.

This one comes in the form of an expected recently extinctified (made up word) giant freshwater fish known as the Chinese paddlefish (Psephurus gladius). It used to haunt the mighty waters of the Yangtze River. These monsters measured in at around 21 feet long, but haven't been spotted in over six years, despite a recent survey conducted to determine their numbers, which look to be approaching zero.

Photo source: BBC
If the Chinese paddlefish is indeed gone, like the Yangtze river dolphin before it, then the title of the world's largest freshwater fish will be bequeathed to another, like the Mekong giant catfish or the arapaima of the Amazon river.

But then, it's suspected that the paddlefish wasn't a true freshwater fish. Ready for new vocab word (for you non-ichthyologists)? Anadromous. That's when a fish lives most of its life in marine environments but then returns to freshwaters to spawn. It's thought that the Chinese paddlefish might have been (or is) anadromous.

But not all is necessarily lost. Though the survey was three years long and the research team employed a variety of tactics to try to locate even a single paddlefish, it's quite possible that individuals eluded the researchers. The Yantze River system is immense and complicated, and there are any number of places where paddlefish, especially smaller ones, could still be found. But without intervention, things don't look good.

I'm thinking that the dissemination of some good ol' misinformation might work here. Tell the fishermen on the Yangtze that hooking or netting a paddlefish will render them impotent for seven years, and we might find a resurgence in their numbers (I always suspect Traditional Chinese Medicine as being a contributor to an Asian animal's decline).

Thanks for the article, Ida.

The Worst Worm Ever

I don't even know where to begin with this worm. I guess I'll start with the tame stuff...

It's a large predatory species, Eunice aphroditois, that can get as large as three meters long, though most specimens measure in at around one meter. It's actually one of the largest worms on the planet. They haunt the rubble zones around coral reefs in the Indo Pacific, coming out at night in search of live fish.

Photo source: Practical Fishkeeping


















So, why my hesitance in posting on this worm? I'll start with its common name: the Bobbit worm. The females of the species eat the ... uh, the ... um. The man parts ... the man bits of the male worm and feed it to their offspring.

I have no idea why they do this. I have a hard time even wanting to know why. Is it for the nutritional value? Does it trigger hormonal changes in the male? Is it needed to complete the act which leads to the very offspring that eat the ... ugh. I can't even say it.



If ever there was an appropriate curse for adulterous men, it would be to die and come back as one of these creatures.

Thanks for the article, Lisa. I, for one, am reminded of how good it is to be a human being.

Of Shear Force and Shingles

What good is a sea urchin without spines? Well, I'll tell you.

Here you've got the Indo Pacific Shingle (or Helmet) Urchin (Colobocentrotus atratus). According to Echinoblog (great site, folks), they are found in rocky intertidal areas of the South and Central Pacific. What benefit does having a helmet-shaped body serve this sea urchin? Turns out that their native waters can flow at high rates, and their shape offsets the effects of shear force.





















But the true power of this little beast is seen only when you upend one. Take a look at those tube feet (especially in the last photo). They enable the shingle urchin to withstand water flows of a couple magnitudes greater than your spiny urchine. Those spines won't do you much good if you're swept away with the current, Mr. Spiny Urchin. Nope, best to keep a low profile, like Mr. Shingle Urchin.

Thanks for the uchin, Jelo.