Boaties warned of skeleton shrimp invasion (NZ)

[Dead_Parrot]

Boaties are being warned to check their hulls for "weird, hitch-hiking" skeleton shrimp invading New Zealand waters.

The marine amphipod crustacean, caprella mutica, are poor swimmers, and are spreading rapidly around the country by attaching themselves to boat hulls or drifting algae to move around.

"They readily colonise artificial structures, at times occurring in huge densities on anchored buoys, fish cages, wharves and vessel hulls," National Institute of Water and Atmospheric Research (Niwa) biosecurity scientist Chris Woods said.

"We have observed densities up to 180,000 caprellids per square metre. Boat owners are saying to us, 'what are these waving things all over the hulls of our boats?' when they slip their craft and discover the hull alive with movement."

http://www.stuff.co.nz/environment/6377148/Boaties-warned-of-skeleton-shrimp-invasion



Fuck they're ugly. and 180k/m²? I'm never going in the water again...

[mike_c]

1. caprellids normally live among seaweed and hydrozoan colonies, like Obelia...

...here on the west coast of north america. We ALWAYS find them in Obelia colonies, which freaks the students out when they see them under the dissecting scope. They're listed as invasive, but I haven't found many reports of ecosystem harm, just range expansion due to human transport primarily. I wonder why New Zealanders are so freaked out? Caprellids certainly don't seem to do any harm here, although at those population densities, which I have never seen them even approach, I'm sure they'd exclude native amphipods and other crustatceans.

on edit-- they were first detected outside their native range here in Humboldt Bay in 1973, so they've been here 40 years and have caused no appreciable ecosystem damage that I know of.

[Dead_Parrot]

2. Maybe, because they look like a Giger nightmare on acid?

Generally, I love nature in all it's glorious diversity but these make me want the nuke the entire ocean. Twice, just be sure.

I'm not even sure which end is the front...

[mike_c]

3. dude, if this bothers you I could post pics that would send you screaming....

Caprellids are actually kind of cute.... Oh, and the pic above doesn't indicate scale well-- those are millimeters so they're actually VERY TINY, quite hard to see well without magnification.

Here's another fun crustacian that IS easy to see:

[Dead_Parrot]

4. Actually, they ARE kind of cute

Wouldn't want to find one in my salad, but at least I can tell what I'm looking at. Same goes for tardigrades...

Which reminds me - tardigrade plushies.

[NYC_SKP]

5. Wow! (nt)