Lodewijk van Walraven
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lodewijkw.bsky.social
Lodewijk van Walraven
@lodewijkw.bsky.social
Marine ecologist at Rijkswaterstaat Hydro biological lab,
jellyfish expert, diver, photographer. Plankton enthusiast.
Sites: http://zooplankton.nl, http://plankton.photography
With all the parts in trans-neon colours DSSV Oithona looks especially stunning under blacklight! #LEGO #SHIPtember #MOC #UFO
September 26, 2024 at 7:01 AM
DSSV Oithona lurks in deep space waiting to ambush unexpecting vessels of Insectoids and other factions. It is equipped with a wide range of long range sensors to detect nearby prey.
#LEGO #SHIPtember #MOC #UFO
September 26, 2024 at 7:01 AM
For the #LEGO #SHIPtember build challenge (build a 100+ stud length spaceship in September) I built Deep Space Scavenging Vessel Oithona: a copepod-inspired spaceship in #UFO style! It uses about 2500 parts.
#MOC
September 26, 2024 at 7:01 AM
In addition to the copepod I also built a #LEGO crab larva (zoea)! #plankton #MOC
What plankton organism should I build next?
September 25, 2024 at 7:00 AM
Finally built the #LEGO #copepod I designed in Studio! Especially like the look of the Ninjago swords and scythes for mouthparts and legs. #plankton #MOC
September 24, 2024 at 7:00 AM
This female Japanese shore crab in the Wadden Sea was busy releasing her babies into the water! You can see the tiny zoea larvae being released into the plankton where they will live for several weeks and many will be eaten. The few survivors settle on the bottom again.
July 4, 2024 at 11:17 AM
We saw a wide range of fish species during our dive in the Wadden Sea off #Texel such as tompot blenny, whiting, rock gunnel, longspined bullhead, fivebeard rockling and even a seabass!
July 4, 2024 at 7:00 AM
The huge mussel spatfall in the Wadden Sea caused a feeding frenzy of sea stars and crabs! Likely within a few weeks most of the mussels will be eaten or washed away by the tides.
July 3, 2024 at 8:41 PM
Diving in the Wadden Sea is rarely possible because of the extremely turbid conditions, but last week we could finally dive again due to very calm conditions. We discovered that every available surface was covered by a thick layer of juvenile mussels "seed"!
July 3, 2024 at 8:36 PM
This week we @WURmarine are trialing the use of the Plankton Imager on RV Tridens during the ICES herring larvae survey in the English Channel. Continuous sampling of zooplankton composition at 1000s of images per min. First images look great! #Plankton #MarineLife.
December 19, 2023 at 9:42 AM
The Norway Lobster Nephrops norvegicus also has planktonic larvae which grow quite big before settling. They are instantly recognisable because of their huge spoiler-like telson! #Plankton #MarineLife
November 29, 2023 at 10:33 AM
When the barnacle larva transforms into its final stage, the cypris larva, it is ready to settle. It swims around sniffing for other barnacles and a nice rock to settle on. Once found it glues itself to the rock and is stuck forever!
#Plankton #MarineLife
November 28, 2023 at 7:00 AM
Barnacles have larvae in the plankton as well! The nauplius larva reveals their crustacean origin - it looks similar to the copepod nauplius larva but can be recognised by the two "horns" and the way it swims rowing its appendages.
#Plankton #MarineLife
November 27, 2023 at 7:00 AM
Phyllosoma larvae are quite rare in the plankton and I only found a few, like this one I found on a Mediterranean holiday. Here imaged using an old school (100+years) microscopic illumination technique called Rheinberg Illumination.
#Plankton #MarineLife
November 26, 2023 at 7:00 AM
Perhaps the weirdest and coolest crustacean larvae are the thin, flat and transparent Phyllosoma larvae of spiny lobsters, slipper lobsters and relatives. They can often be seen riding on- and eating jellyfish!
#plankton #MarineLife
November 25, 2023 at 7:00 AM
After moulting a few times as zoea larva the crabs enter their final larval stage; the megalopa which already looks like a tiny adult crab, which will settle on the seafloor. These crab larvae are voraceous predators of the plankton!
#plankton #MarineLife
November 24, 2023 at 7:00 AM
This is the cutest crab larva of all: the larva of the pea crab Pinnotheres pisum! It has only small spines and is already as round as the adults.
#plankton #MarineLife
November 23, 2023 at 7:00 AM
Here is another zoea larva of a brackish water crab ( Rhithropanopeus harrisii). This one has super long spines!
#plankton #MarineLife
November 22, 2023 at 5:12 PM
Perhaps this paper has the answer? www.researchgate.net/publication/...
November 21, 2023 at 3:47 PM
Crustaceans such as crabs, shrimp and even barnacles often have a larval stage in the plankton. These can have bizarre shapes! This is a zoea stage larva of a crab, which has long spines to decrease its chance of being eaten by predators. #plankton #MarineLife
November 21, 2023 at 8:00 AM
Many bottom dwelling organisms like crabs, worms, sea stars and barnacles have larval stages in the plankton. Carried by currents the larvae can be transported to other areas. Often the larval stage does not look like the adult at all! Can you guess which is which? #MarineLife
November 21, 2023 at 7:00 AM
I am a marine biologist studying zooplankton using innovative tools like in-situ imaging devices and genetics. In my spare time I like to spend hours at the microscope to capture images of the beautiful and bizzarre planktonic creatures. I'll try to share an image every day!
November 20, 2023 at 9:58 PM